CN108474248A

CN108474248A - Method and system for definitely descending crack closure

Info

Publication number: CN108474248A
Application number: CN201680078520.1A
Authority: CN
Inventors: 查德·坎南; 路易斯·巴特尔; 特里·帕里什; 大卫·奥尔德里奇; 托德·罗珀; 史蒂夫·萨沃伊; 丹尼尔·R·米切尔
Original assignee: Carbo Ceramics Inc; Sandia Corp
Current assignee: Carbo Ceramics Inc; National Technology and Engineering Solutions of Sandia LLC
Priority date: 2015-11-16
Filing date: 2016-11-15
Publication date: 2018-08-31
Also published as: EA201891194A1; AR106700A1; WO2017087348A1

Abstract

Disclosed herein is the method and systems for definitely descending crack closure.Method may include powering to the casing of wellhole, described sleeve pipe is extended to from the surface of the earth in stratum, the stratum has the crack for being at least partially filled with conductive supporting agent, and the first electric field response is measured to provide the first field measure at the surface or in adjacent wellbore in first time interval.This method can also be included in the second time interval and measure the second electric field response at the surface or in the adjacent wellbore to provide the second field measure, and the increase that pressure is closed in the conductive supporting agent is determined by the difference between first field measure and second field measure.

Description

Method and system for definitely descending crack closure

Cross reference to related applications

This application claims the priority for enjoying in 14/942, No. 304 U.S. Patent applications that on November 16th, 2015 submits, It is incorporated into herein by quoting entirety, and the application is 14/572, No. 486 United States Patent (USP) Shens submitted on December 16th, 2014 Continuation in part application please, by quoting whole be incorporated into herein.The application still submitted within 23rd within 2 months in 2015 14/ The continuation in part application of No. 629,004 U.S. Patent applications, No. 14/593,447 United States Patent (USP) submitted on January 9th, 2015 The continuation in part application of application, No. 14/147,372 U.S. Patent application submitted on January 3rd, 2014, nowadays 8,931,553 The connecting application of number United States Patent (USP) and PCT/US2014/010228 international patent applications, each of these existing applications By quoting whole be incorporated into herein.No. 14/629,004 U.S. Patent application, No. 14/593,447 U.S. Patent application, 14/ No. 147,372 U.S. Patent applications and PCT/US2014/010228 international patent applications each require to enjoy in 2013 1 The equity for the U.S. Provisional Patent Application 61/749,093 that the moon is submitted on the 4th, the U.S. Provisional Application is by quoting whole be incorporated into Herein.

Technical field

The embodiment of the present invention is usually related to the hydraulic fracturing of geological stratification, is more particularly in gas reservoir, oil reservoir or underground heat The conductive supporting agent used in the hydraulic fracturing excitation of storage.The embodiment of the present invention relate to the use of conductive supporting agent method and System.

Background technology

In order to from formation downhole, particularly with compared with low-porosity and/or the excitation of smaller infiltrative rock stratum and more effective Ground produce hydrocarbon, usually used technology be hydrocarbon-containiproducts rock stratum induced fractures (also referred to as " fracturing operation ", " hydraulic fracturing " or referred to as " pressure break ").In typical fracturing operation, fluid is pumped into underground under high pressure, thus makes It obtains rock stratum to rupture around drilling, to build the high osmosis pipeline for promoting hydrocarbon inflow drilling.These fracturing operations It can be carried out in horizontal, deviateing, vertical drilling, and in the interval of no cased well or cased well across perforation It carries out.

Such as in the cased bore-bole of Vertical Well, high-pressure fluid leaves drilling via perforation and passes through casing and encirclement water Mud, and lead to rock breakdown, be usually relatively thin and roughly vertical sheet rupture in finding the gentle deeper rock stratum of oil. These created fractures generally laterally extend apparent distance and leave the rock stratum that wellhole enters surrounding, and vertically extend straight It is reached under the rock stratum being not easily broken and/or desired rupture interval to rupture.In general, if the fluid for being pumped into underground (has When referred to as mud) be not contained in the solid being stuck in when fluid pressure absent-mindedness in crack, then crack re-closes, and loses permeability The overwhelming majority of duct gain.These solids (being known as proppant) are usually made of sand grains or cement granules, are placed on induction To prevent it from re-closing completely in crack.In mud pumping to underground and after discharging fluid pressure, formation wall is supporting It is closed to generate " the support rupture " in the channel that high flow conductivity is usually provided in the earth formation in agent.The time of crack closure with Rock stratum is related and can not be directly measured at present.

Although induced fractures have been highly effective tools in producing hydrocarbon, by the process The amount of the excitation of offer, which is heavily dependent on, to be generated new crack or foundation or extends crannied ability and pass through branch It supports the appropriate selection of agent and places the ability for keeping open fissure.

Whether cannot obtain for detecting the closing time in crack to select and place to confirm proppant is suitable reliable Method.

Therefore, it is necessary to be used to detect crack when and where be closed to determine fracture closure times and crack closure journey The method of degree.

Description of the drawings

The present invention can be best understood by following description for illustrating the embodiment of the present invention and attached drawing.In attached drawing In：

Fig. 1 is the geometric layout figure in Vertical Well or deviation well, and there is shown with different electrical property and engineering properties Big stratum.

Fig. 2 is across the installation horizontal wellbore casing with the hydrocarbon-containiproducts region for being filled with proppant in crack The schematic diagram of column, wherein show the big stratum with different electrical properties and engineering properties.

Fig. 3 is the schematic sectional view of fracturing system, shows two embodiments that electric current is introduced to wellhole, that is, It powers to wellhole at surface or utilizes sinker bar via line powered near the perforation of wellhole.

Fig. 4 is the schematic plan view of fracturing system.

Fig. 5 is the schematic perspective view of fracturing system.

Fig. 6 A are the schematic diagrames of insulating sleeve of electric pipe fitting.

Fig. 6 B are the schematic diagrames of electrical isolation casing coupling.

Fig. 7 A are the schematic sectional views of proppant filling hydraulic fracturing before being closed.

Fig. 7 B are the schematic sectional views of proppant filling hydraulic fracturing after being closed.

Fig. 8 is the schematic diagram of the test system for detecting proppant resistance.

Fig. 9 is leading for the CARBOLITE 20/40 with the nickel coating and CARBOLITE with copper coating 20/40 The curve graph of electric rate (Siemens/rice) and pressure (pound/square inch, psi).

Figure 10 is the conductivity (Siemens/rice) and pressure for the CARBOLITE 20/40 with different-thickness nickel coating The curve graph of (psi) by force.

Figure 11 shows that a pair of of the straight line on the horizontal segment along hoistway simulates the voltage measured between electric-field sensor The profile of simulation.

Specific implementation mode

In the following description, several details are proposed.However, it is to be understood that the embodiment of the present invention is not having these specific It can also implement in the case of details.In other examples, well known structure and technology are not yet illustrated in detail in not obscure this The understanding of specification.

Described herein is the method for determining crack closure.Specifically, disclosed herein is pass through leading in fracture Electricity sintering, roughly circular and spheric granules proppant pack power supply determines the closing time in crack.There is disclosed herein Electromagnetic method, wherein include powering to the earth or at or near the crack at certain depth and measuring when a series of Between the surface of the interval measurement earth or the electromagnetic response of neighbouring wellhole/drilling.

Conduction is sintered, roughly circular and spheric granules (hereinafter referred to as " conductive supporting agent ") can pass through electromagnetism (EM) method detects.Conductive supporting agent may include one or more coatings of conductive material on its outer surface.Herein The middle term " roughly circular or spherical " used and correlation form be limited to refer to minimum diameter and maximum gauge average specific Rate is about 0.8 or bigger, or the average sphericity with about 0.8 or bigger compared with Krumbein and Sloss tables.

Electromagnetic method described herein may include in rupture well/drilling or well/drilling adjacent with rupture well/drilling The earth power supply.Electromagnetic method described herein can be in conjunction with Cased well bore (such as well 20 shown in Fig. 1) or without cased well Hole (not shown) is used together.As shown in Figure 1, in the form of with three-dimensional component, casing 22 extends in well 20 and well 20 Extend through geological stratification 24a-24i.

Referring now to Fig. 2, show that phantom, producing well 20 extend through one or more geological stratifications straight down It 24a-24i and is horizontally extended on layer 24i.Although well is conventionally vertical, electromagnetic method described herein is not It is limited to be used together with Vertical Well.Therefore, term "vertical" and "horizontal" are used for general sense when being related to the well of various orientations.

The preparation for hydraulic fracturing of producing well 20 includes drilling bore hole 26 to desired depth and later in some situations Under make hole 26 horizontally extend so that hole 26 have any desired degree vertical component and horizontal component.Casing 22 can cohere 28 in well 20 with from the geological stratification 24a-24i sealing holes 26 in Fig. 2.Casing 22 can have multi-openings 30 and/or sliding Sleeve (not shown).Perforation 30 is shown in the horizontal component of well 20 in fig. 2, but it will be appreciated by persons skilled in the art that penetrates Hole can be located at or along at any desired depth or horizontal distance in hole 26 but be usually located at the carbon containing of geological stratification 24 At the position in hydrogen compound region (can be in geological stratification 24a-24j in one or more).Those skilled in the art will also meaning It can not includes casing to know well 20, such as in the case of open hole well.Hydrocarbon-containiproducts region may include oil and/or gas And other fluids and the material with fluid class property.Hydrocarbon-containiproducts region in geological stratification 24a-24j will be by that will flow Body is pumped into casing 22 and passes through perforation 30 to generate crack 32 with enough rate and pressure, and fluid is made to include leading later Electric proppant, wherein the conductive supporting agent struts the crack 32 of generation when discharging the hydraulic pressure for generating crack.

Hydraulic fractures 32 shown in Figure 2 are orientated radially remote from metal casing 22.It is example in the directional nature Property.In fact, hydraulic pressure induce crack 32 can as be oriented radially, be laterally oriented in Fig. 2 either both of the above it Between medially orientation.Each orientation is exemplary and is not intended to limit or limit electricity described herein in any way Magnetism method.

During any suitable hydraulic fracturing operations, conductive supporting agent can introduce one or more subterranean fractures to carry For conductive supporting agent filling layer.During one or more exemplary hydraulic fracturing operations, conductive supporting agent and non-conductive support Any combinations of agent can be introduced into one or more cracks to provide conductive supporting agent filling layer.Conductive supporting agent filling layer Conductive supporting agent includes the non-uniform coating of conductive material and/or the substantially non-uniform coating of conductive material.

Some embodiments of electromagnetic method according to the present invention and as Fig. 3 is schematically shown, electric current is in wellhole 20 It is (such as well known to those skilled in the art and from Camesa Wire, Rochester by seven strands of wire insulation cables 34 Wire and Cable, Inc., WireLine Works, Novametal Group and Quality Wireline＆Cable Inc. those of commercially available cable extensively) it is transported down to supply terminals, which is usually located at 10 of the perforation 30 in casing 22 Rice or farther place (on or below).In other exemplary embodiments, wire insulation cable 34 may include 1 to 6 strand or 8 Stock or more multiply.The sinker bar 36 for being connected to electric wire 34 contacts or close adjacent with casing 22, therefore well Casing 22 becomes to generate the electric current line source of subsurface electromagnetic field.In other exemplary embodiments, in addition to sinker bar 26 Either alternatively electric wire 34 may be coupled to or be otherwise attach to centralizer and/or other suitable undergrounds Tool.These are interacted with the crack 32 comprising conductive supporting agent to generate the crack that can be used for detecting filling proppant 32 closure and the two-stage electromagnetic field of closing time.

Some embodiments of electromagnetic method according to the present invention and as Fig. 3 is schematically shown, power control box 40 is logical It crosses cable 42 and is connected to casing 22 to provide for the electric current return via 36 Injection Current of sinker bar.Other embodiment It is that power control box 40 is directly connected to the earth by cable 54.Other embodiment is returned using the electric current for being connected to the earth Telegram in reply cable 54 to the directly power supply of casing 22 at well head or any other suitable surface location by injecting a current into crack Well 20.In one embodiment, power control box 40 is connected wirelessly to by receiver/transmitter 43 on equipment truck 41 Receiver/transmitter 39.It will be appreciated by persons skilled in the art that can also use transfer current to supply terminals other are suitable Mode.

Current source be configurable to generate various types of input current waveforms (that is, pulse, continuous wave or repetitive pattern or Periodic waveform or pseudo-random binary pulse), the input current waveform generate with amplitude corresponding with input current waveform and The input electromagnetic field waveform of corresponding time response.Therefore, conductive casings can be powered and be used as the spatially extended of electric current Source.

The following electric current generated by the source can travel across the proppant of the created fractures 32 of geological stratification from casing 22. Electromagnetic field being generated by the electric current in casing 22 and being transferred to each position in earth volume can be supported agent injection and split Existing proppant changes after seam 32.By casing and it is transmitted to each position in earth three-D volumes using sensor sensing The electromagnetic field that generates of both proppants.

If Fig. 3 to 5 is schematically shown, multiple emf sensors 38 are placed on rectangle or other suitable arrays On earth surface and cover the region around crack well 20 and on the crack 32 being related to.In one embodiment, it passes Sensor 38 is connected wirelessly to receiver/transmitter 39 on equipment truck 41.Usually, the full-size of array (hole) should It is at least the 80% of crack area depth.Numerical simulation of optimum sensing station splitting for detection proppant filling can be used Seam 32.Sensor 38 will sense the x, y, z component response of electromagnetic field.These responses will be used by and be used to determine response The numerical simulation of the measurement data in source and/or the inverse closure and closing time for being compared to infer conductive supporting agent filling.Electricity The response of magnetic-field component will depend on：The orientation of crack well 20, the orientation in crack 32, the conductivity of layer 24a-24j, magnetic permeability and The volume of capacitivity, conductivity, magnetic permeability and the capacitivity in proppant filling crack 32 and proppant filling crack 32.And And the conductivity, magnetic permeability and capacitivity of existing geological stratification influence the sound of record between surface and target formation 24a-24j It answers.It can be by on-the-spot record in response to determining that proppant fills the details in crack 32, such as position and closure.

In a further embodiment, electromagnetic sensor can be located in adjacent well/drilling.

According to the conductivity of the earth around casing 22, the electric current when electric current returns to surface along the flowing of casing 22 It may or may not be uniform.Two embodiments shown according to fig. 3, electric current is along wellhole 20 (such as along path 50 or 52) Occur to reveal and returns to the electrical ground 54 established at well head.As entitled " Simulating Current Flow Through a Well Casing and an Induced Fracture ", submitted within 9th in August in 2011 13/206,041 (its entire disclosure is incorporated herein) description of number U.S. Patent application description, casing is in data analysis sum number Leakage transmission line is expressed as in value modeling.Numerical simulation has been shown that (conductivity is greater than about 0.05 Siemens for conductive the earth Every meter (S/m)), leakage of current enters rock stratum, however if conductivity is less than about 0.05S/m, electric current will be along casing 22 It is almost uniform.As shown in Figure 6 A and 6B, in order to make electric current localize in casing 22, electric insulating tube connector can be installed Or pipe collar.According to the embodiment shown in Fig. 6 A, the cooperation of connector can be coated by using the material 64 with high dielectric strength Insulating joint is installed on surface 60 and 62, the material 64 be, for example, it is with high dielectric strength and be it is tough and tensile and it is flexible with Joint surface is adapted for attachment to known to any type at the suitable position that is maintained between joint surface and can quotient The plastics or resin material of purchase.As described in No. 2,940,787 United States Patent (USP)s (its entire disclosure is incorporated by reference into this Text), this plastics or resin material include epoxy resin, phenolic resin, rubber constituent and alkyd nd various combinations thereof.Additionally Material include polyetherimide and Noryl.According to embodiment shown in Fig. 6 B, the cooperative end part 70 and 72 of connector The cooperative end part 70 and 72 of connector is engaged with insulating sleeve of electric pipe collar 74.Transmission line representation can handle various casing scenes, Such as only Vertical Well, inclined shaft, the vertically and horizontally section of casing and single or multiple insulating voids and for consolidating casing Cement.

Conductive supporting agent filling layer may include multiple conductive supporting agent particles, each in multiple conductive supporting agent particles Person can be with the substantially uniform coating of conductive material.The substantially uniform coating of conductive material can have any suitable Thickness.In one or more exemplary embodiments, the thickness that the substantially uniform coating of conductive material can have is about 5nm, about 10nm, about 25nm, about 50nm, about 100nm or about 200nm are to about 300nm, about 400nm, about 500nm, about 750nm, about 1,000, about 1,500nm, about 2,000nm or about 5,000nm or thicker.For example, the substantially uniform coating of conductive material Thickness can from about 10nm to about 300nm, from about 400nm to about 1,000nm, from about 200nm to about 600nm or from about 100nm To about 400nm.

In one or more exemplary embodiments, conductive supporting agent may include the irregular or non-homogeneous of conductive material Coating.The non-uniform coating of conductive material can cover or coat any desired part on the surface of proppant particles.At one Or in multiple exemplary embodiments, the coating of conductive material can cover the surface of conductive supporting agent particle at least about 10%, At least about 15%, at least about 20%, at least about 30%, at least about 40% or at least about 50%.In one or more exemplary realities Apply in example, the coating of conductive material can cover the surface of conductive supporting agent particle be less than 100%, less than 99%, be less than 95%, less than 90%, less than 85%, less than 80%, less than 75%, less than 65%, less than 50%, less than 40% or it is less than 35%.In one or more exemplary embodiments, the pact on the surface of conductive supporting agent particle can be covered by conductive material 25%, about 30%, about 35% or about 45% to about 55%, about 65%, about 75%, about 85%, about 90%, about 95% or about 99% or more.For example, the coating of conductive material can cover the surface of conductive supporting agent particle from about 10% to about 99%, From about 15% to about 95%, from about 20% to about 75%, from about 25% to about 65%, from about 30% to about 45%, from about 35% To about 75%, from about 45% to about 90% or from about 40% to about 95%.

The non-uniform coating of conductive material can have any suitable thickness.In one or more exemplary embodiments In, average thickness that the non-uniform coating of conductive material can have is from about 5nm, about 10nm, about 25nm, about 50nm, about 100nm or about 200nm to about 300nm, about 400nm, about 500nm, about 750nm, about 1,000, about 1,500nm, about 2,000nm or About 5,000nm is thicker.For example, the average thickness of the non-uniform coating of conductive material can from about 400nm to about 1, 000nm, from about 200nm to about 600nm or from about 100nm to about 400nm.The non-uniform coating of conductive material can also have Any suitable thickness change.In one or more exemplary embodiments, the thickness of the non-uniform coating of conductive material can be with From about 10nm to about 1,000nm, from about 50nm to about 500nm, from about 100nm to about 400nm or from about 400nm to about 1, 000nm。

Conductive supporting agent filling layer can have any suitable conductivity.In one or more exemplary embodiments, The conductivity that conductive supporting agent filling layer can have is at least about 1 every meter of Siemens (S/m), at least about 5S/m, at least about 15S/m, at least about 50S/m, at least about 100S/m, at least about 250S/m, at least about 500S/m, at least about 750S/m, at least about 1,000S/m, at least about 1,500S/m or at least about 2,000S/m.The conductivity of the group can also from about 10S/m, about 50S/m, About 100S/m, about 500S/m, about 1,000S/m or about 1,500S/m to about 2,000S/m, about 3,000S/m, about 4,000S/m, About 5,000S/m or about 6,000S/m.Conductive supporting agent filling layer can have any suitable resistivity.In one or more In exemplary embodiment, resistivity which can have be less than 100Ohm-cm, be less than 80Ohm-cm, be less than 50Ohm-cm, Less than 25Ohm-cm, be less than 15Ohm-cm, be less than 5Ohm-cm, be less than 2Ohm-cm, be less than 1Ohm-cm, be less than 0.5Ohm-cm, Or it is less than 0.1Ohm-cm.

Conductive supporting agent filling layer can also include any proper amount of non-conductive support agent.Non-conductive support agent can have There is any suitable resistivity.For example, the resistivity that non-conductive support agent can have is at least about 1 × 10⁵Ohm-cm, at least About 1 × 10⁸Ohm-cm, at least about 1 × 10¹⁰Ohm-cm, at least about 1 × 10¹¹Ohm-cm or at least about 1 × 10¹²Ohm-cm.It leads Electric proppant pack may include any proper amount of non-conductive support agent.In one or more exemplary embodiments, lead Electric proppant pack may include at least about 1% calculated by weight, at least about 5%, at least about 10%, at least about 20%, At least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90% or at least about 95% non-conductive support agent.In one or more exemplary embodiments, conductive supporting agent filling layer may include by weight Calculate at least about 1%, at least about 5%, at least about 10%, at least about 20%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90% or at least about 95% conductive supporting agent.Show in one or more A in example property embodiment, the conductive supporting agent concentration that conductive supporting agent filling layer can have is based on the total of proppant pack About 2% calculated by weight, about 4%, about 8%, about 12%, about 25%, about 35% or about 45% of weight to about 55%, about 65%, about 75%, about 85% or about 95%.In one or more exemplary embodiments, conductive supporting agent filling layer can be with With calculate by weight from about 1% to about 10%, from about 10% to about 25%, from about 25% to about 50%, from about 50% to About 75% or from about 75% to about 99% non-conductive support agent.Non-conductive support agent can divide in any suitable manner It is dispersed in entire conductive supporting agent filling layer.For example, non-conductive support agent can substantially evenly be dispersed in entire conductive supporting In agent filling layer.

Including the conductive supporting agent filling layer of non-conductive support agent can have any suitable resistivity.At one or more In a embodiment, led including calculating by weight at least about 20%, at least about 40%, at least about 50% or at least about 60% non- The resistivity that the conductive supporting agent filling layer of electric proppant can have is less than 1,000Ohm-cm, is less than 500Ohm-cm, small In 500Ohm-cm, be less than 200Ohm-cm, be less than 100Ohm-cm, be less than 80Ohm-cm, be less than 50Ohm-cm, be less than 25Ohm- Cm, less than 15Ohm-cm, less than 5Ohm-cm, less than 2Ohm-cm, less than 1Ohm-cm, less than 0.5Ohm-cm or be less than 0.1Ohm-cm.Including the conductive supporting agent filling layer of non-conductive support agent can have any suitable conductivity.At one or In multiple exemplary embodiments, including calculating by weight at least about 20%, at least about 40%, at least about 50% or at least about 60% The conductivity that the conductive supporting agent filling layer of non-conductive support agent can have is at least about 0.1S/m, at least about 0.5S/m, extremely Few about 1S/m, at least about 5S/m, at least about 15S/m, at least about 50S/m, at least about 100S/m, at least about 250S/m, at least about 500S/m, at least about 750S/m, at least about 1,000S/m, at least about 1,500S/m or at least about 2,000S/m.

According to an embodiment of the invention, conductive supporting agent filling layer can by conventional proppants (for example, ceramic proppant, Sand, plastic bead and bead) manufacture.This conventional proppant can (it includes but unlimited according to any suitable process In continuous spray atomization, spray-fluidized, spray drying or compression) manufacture.Suitable conventional proppants and the side manufactured for it (it is complete in No. 4,068,718, No. 4,427,068, No. 4,440,866, No. 5,188,175 and No. 7,036,591 United States Patent (USP)s for method Portion, which discloses, to be incorporated herein) in disclose.

The property (such as apparent specific gravity) of ceramic proppant by initial raw materials with manufacturing process difference.It uses herein Term " apparent specific gravity " be particle (including internal void) per unit volume weight (gram per cubic centimeter).Low-density branch Support agent is typically below 3.0g/cm³Apparent specific gravity and usually by kaolin and other aluminium oxide, oxide or silicate Ceramics manufacture.Medium density proppant usually has about 3.1 to arrive 3.4g/cm³Apparent specific gravity and usually manufactured by alumina.It is high Strength support agent is usually by the alumina manufacture with aluminium oxide and with 3.4g/cm³Above apparent specific gravity.

As described herein, the roughly circular and spherical particle or branch being sintered by salic raw material slurrying Support agent.In some embodiments, the alumina content that particle has is calculated by weight from about 40% to about 55%.Some other In embodiment, the alumina content that the roughly circular and spheric granules of sintering has is calculated by weight from about 41.5% to about 49%.

In some embodiments, the bulk density that proppant has is from about 1.35g/cm³To about 1.55g/cm³.Herein The term " bulk density " used refers to (being included in the volume of consideration) per unit volume in void space between particle Weight.In some other embodiments, the bulk density that proppant has is from about 1.40g/cm³To about 1.50g/cm³。

According to some exemplary embodiments, proppant has any suitable permeability and flow conductivity, according to ISO 13503-5 the step of " long-term flow conductivity " for measuring proppant and it is expressed as darcy unit (D).Proppant 7, The prolonged permeation rate that can have under 500psi be at least about 1D, at least about 2D, at least about 5D, at least about 10D, at least about 20D, At least about 40D, at least about 80D, at least about 120D or at least about 150D.Proppant can have long-term at 12,000psi Permeability is at least about 1D, at least about 2D, at least about 3D, at least about 4D, at least about 5D, at least about 10D, at least about 25D or extremely Few about 50D.The long-term flow conductivity that proppant can have at 7,500psi is at least about 100 millidarcies-foot (mD- Ft), at least about 200mD-ft, at least about 300mD-ft, at least about 500mD-ft, at least about 1,000mD-ft, at least about 1, 500mD-ft, at least about 2,000mD-ft or at least about 2,500mD-ft.For example, proppant can have at 12,000psi Long-term flow conductivity be at least about 50 millidarcies-foot (mD-ft), at least about 100mD-ft, at least about 200mD-ft, at least About 300mD-ft, at least about 500mD-ft, at least about 1,000mD-ft or at least about 1,500mD-ft.

In some embodiments, the crushing strength that proppant has at 10,000psi be from about 5% to about 8.5% with And the long-term flow conductivity at 10,000psi is from 2500mD-ft to about 3000mD-ft.In some other embodiments, branch It is from about 5% to about 7.5% to support crushing strength of the agent at 10,000psi.

Proppant can have any suitable apparent specific gravity.In one or more exemplary embodiments, proppant tool Some apparent specific gravities are less than 5, be less than 4.5, be less than 4.2, be less than 4, be less than 3.8, be less than 3.5 or are less than 3.2.In other implementations In example, apparent specific gravity that proppant has be from 2.50 to about 3.00, from 2.75 to about 3.25, from 2.8 to about 3.4, from 3.0 to About 3.5 or from 3.2 to about 3.8.In one or more exemplary embodiments, apparent specific gravity that proppant has is about 5 or more It is small, about 4.5 or smaller, about 4.2 or smaller, about 4 or smaller or about 3.8 or smaller.Terms used herein " apparent specific gravity " (ASG) refer to no unit number, be defined as volume numerically equal to per cubic centimeter and (including determine that the gap in volume is empty Between or open pore) weight grams.

In one or more exemplary embodiments, pottery can be manufactured in the way of building hole in proppant coarse grain Porcelain proppant.The method for manufacturing suitable porous ceramic support agent is described in 7,036, No. 591 United States Patent (USP)s, it is all public It opens and is incorporated herein.In this case, conductive material can be impregnated into the hole of proppant coarse grain so that It is a concentration of based on conductive supporting agent weight calculate by weight about 0.01%, about 0.05%, about 0.1%, about 0.5%, about 1%, About 2% or about 5% to about 6%, about 8%, about 10%, about 12%, about 15% or about 20%.Water-soluble coating (such as poly- breast Acid) it can be used for coating these particles to allow delay/time controlled released conductive particle.

Ceramic proppant can have any suitable porosity.What the inside that ceramic proppant may include interconnected Porosity is from about 1%, about 2%, about 4%, about 6%, about 8%, about 10%, about 12% or about 14% to about 18%, about 20%, about 22%, about 24%, about 26%, about 28%, about 30%, about 34%, about 38% or about 45% or bigger.Show at some In example property embodiment, the porosity that the inside of ceramic proppant is connected with each other is from about 5% to about 35%, from about 5% to about 15% or from about 15% to about 35%.According to some exemplary embodiments, ceramic proppant can have any suitable average Pore-size.For example, the average pore size that can have of ceramic proppant be in its full-size from about 2nm, about 10nm, About 15nm, about 55nm, about 110nm, about 520nm or about 1,100nm are to about 2,200nm, about 5,500nm, about 11,000nm, about 17,000nm or about 25,000nm or bigger.For example, the average pore size that ceramic proppant can have is its full-size In from about 3nm to about 30,000nm, from about 30nm to about 18,000nm, from about 200nm to about 9,000nm, from about 350nm to About 4,500nm or from about 850nm to about 1,800nm.

The roughly circular and spheric granules being properly sintered can also include inducing dropping method (herein referred as according to vibration " drippage casting ") manufacture proppant.In 8,865,631,8,883,693,9,175,210 United States Patent (USP)s and 14/502,483 With 14/802, the proppant that suitable drippage casting method is disclosed in 761 U.S. Patent applications and is especially manufactured, whole It is open to be incorporated herein.The proportion that the proppant manufactured by drippage casting method can have is at least about 2.5, extremely Few about 2.7, at least about 3, at least about 3.3 or at least about 3.5.The ratio that the proppant manufactured by drippage casting method can have Weight is about 5 or smaller, about 4.5 or smaller or about 4 or smaller.Drippage casts the surface roughness that proppant can also have Less than 5 μm, be less than 4 μm, be less than 3 μm, be less than 2.5 μm, be less than 2 μm, be less than 1.5 μm or be less than 1 μm.Show in one or more In example property embodiment, the average maximum pore size that has of drippage casting proppant be less than about 25 μm, less than about 20 μm, be less than About 18 μm, less than about 16 μm, less than about 14 μm or less than about 12 μm and/or the standard deviation of pore-size be less than about 6 μm, Less than about 4 μm, be less than about 3 μm, be less than about 2.5 μm, be less than about 2 μm, be less than about 1.5 μm or be less than about 1 μm.At one or more In a exemplary embodiment, drippage casting proppant has visible when proppant particles every square centimeter amplify 500 times Hole be less than 5,000, be less than 4,500, be less than 4,000, be less than 3,500, be less than 3,000, be less than 2,500 It is a or be less than 2,200.

The proppant manufactured by drippage casting method or conventional method can have any suitable ingredient.Proppant can be with It is or including any proper amount of silica and/or aluminium oxide.According to one or more embodiments, proppant includes being based on Proppant total weight is calculated by weight less than 80%, is less than 60%, is less than 40%, is less than 30%, is less than 20%, is less than 10% Or the silica less than 5%.According to one or more embodiments, proppant includes calculating by weight from about 0.1% to about 70% silica, from about 1% to about 60% silica, from about 2.5% to about 50% silica, from about 5% To about 40% silica, from about 10% to about 30% silica.According to one or more embodiments, proppant includes Based on proppant total weight calculate by weight at least about 30%, at least about 50%, at least about 60%, at least about 70%, at least About 80%, at least about 90% or at least about 95% aluminium oxide.According to one or more embodiments, proppant includes by weight Calculate from about 30% to about 99.9% aluminium oxide, from about 40% to about 99% aluminium oxide, the oxidation from about 50% to about 97% Aluminium, from about 60% to about 95% aluminium oxide or from about 70% to about 90% aluminium oxide.In one or more embodiments, by The proppant of process manufacture disclosed herein may include aluminium oxide, bauxite, kaolin or its any mixture.For example, branch Support agent can be wholly or substantially made of aluminium oxide, bauxite, kaolin or its any mixture.Term " kaolin " is in ability In domain it is widely known and may include with based on roasting calculate by weight at least about 40% alumina content and be based on The raw material for calculating by weight at least about 40% dioxide-containing silica of roasting.Term " bauxite " is widely known in the art And it can be or include the raw material with the alumina content for calculating by weight at least about 55% based on roasting.

Proppant can also have any suitable size.According to one or more exemplary embodiments, proppant can be with The size having is at least about 100 mesh, at least about 80 mesh, at least about 60 mesh, at least about 50 mesh or at least about 40 mesh.For example, branch The size that can have of support agent be from about 115 mesh to about 2 mesh, from about 100 mesh to about 3 mesh, from about 80 mesh to about 5 mesh, from about 80 Mesh to about 10 mesh, from about 60 mesh to about 12 mesh, from about 50 mesh to about 14 mesh, from about 40 mesh to about 16 mesh or from about 35 mesh to about 18 Mesh.In a particular embodiment, the size that proppant has is from about 20 U.S.'s mesh (U.S.Mesh) to about 40 U.S.'s mesh (U.S.Mesh)。

According to certain embodiments described herein, proppant manufactures in continuous process, and in other embodiments, support Agent manufactures in batch process.

Any suitable stage in these proppants in the manufacturing process of any one can add conductive material (such as Metal, conducting polymer or conductive particle) to lead to the conductive supporting agent for being suitable for using according to some embodiments of the present invention. Conductive material can also be added in any one of these proppants after the manufacture of proppant.In one or more examples In property embodiment, proppant can be porous propping agent so that conductive material can immerse or inject in the aperture of proppant with Conductive supporting agent is provided.Porous propping agent can also impregnate or be perfused any appropriate amount and (such as calculate by weight from about 1% to about 15%) conductive material.Water-soluble coating (such as polylactic acid) can be used for coating these particles to allow prolonging for conductive particle Late/time controlled released.

Conductive material can be or including any suitable conductive metal.For example, metal can be or including iron, silver, gold, Copper, aluminium, calcium, tungsten, zinc, nickel, lithium, platinum, palladium, rhodium, tin, carbon steel or any combination thereof or oxide.In one or more examples Property embodiment in, conductive material can be selected from aluminium, copper, nickel and phosphorus and one or more of its alloy or mixture.It leads Electric proppant, which can have, calculates by weight about 0.01%, about 0.05%, about 0.1%, about 0.5%, about 1%, about 2% or about The conductive metal concentration of 5% to about 6%, about 8%, about 10%, about 12% or about 14%.In one or more exemplary embodiments In, metal may include aluminium, copper and mickel and can be added to cause to calculate by weight from about 5% to about 10% metal and contain The proppant of amount.

Conductive metal can be or including any suitable conducting polymer.Suitable conducting polymer includes poly- (3,4- Ethyl dioxy thiophene) poly- (styrene) (PEDOT:PSS it), polyaniline (PANI) and polypyrrole (PPY) and can be added to Lead to the proppant with any Suitable conductive polymer content (such as calculating by weight from about 0.1% to about 10%).One In a or multiple exemplary embodiments, conductive supporting agent can have calculate by weight about 0.01%, about 0.05%, about 0.1%, The conducting polymer of about 0.5%, about 1%, about 2% or about 5% to about 6%, about 8%, about 10%, about 12% or about 14% is dense Degree.Suitable PEDOT:PSS, PANI and PYY conducting polymer are commercially available from Sigma-Aldrich.

Conductive material can be or including any suitable conductive particle.Suitable conductive particle include graphite, single layer or Double-walled Carbon Nanotube shows sufficiently conductive rate to allow to carry out in the present invention when being present in nano-scale particle magnitude range The other materials of detection.Suitable conductive particle can also include any suitable metal, for example, iron, silver, gold, copper, aluminium, calcium, Tungsten, zinc, nickel, lithium, platinum, tin, carbon steel or any combination thereof or oxide.This conductive particle can be added to cause to have by Weight calculate about 0.01%, about 0.05%, about 0.1%, about 0.5%, about 1%, about 2% or about 5% to about 6%, about 8%, The conductive supporting agent of about 10%, about 12% or about 14% conductive particle concentration.In one or more exemplary embodiments, lead The conductive nano-particles content that electric proppant can have is to calculate by weight from about 0.1% to about 10%.

Conductive particle can have any suitable size.In one or more exemplary embodiments, conductive particle tool The full-size of some sizes from about 1 nanometer (nm), about 5nm, about 10nm, about 50nm, about 100nm, about 500nm or about 1, 000nm to about 2,000nm, about 5,000nm, about 10,000nm, about 15,000nm or about 20,000nm.For example, conductive particle Full-size can from about 2nm to about 25,000nm, from about 25nm to about 15,000nm, from about 50nm to about 10,000nm, from About 150nm to about 7,500nm, from about 250nm to about 4,000nm or from about 750nm to about 1,500nm.The maximum of conductive particle Size can also from about 2nm to about 2,000nm, from about 20nm to about 500nm, from about 40nm to about 300nm, from about 50nm to about 250nm, from about 75nm to about 200nm or from about 100nm to about 150nm.

In one or more exemplary embodiments of the present invention, conductive particle is nanosized or nano particle. In one or more exemplary embodiments, the full-size of the size that conductive nano-particles can have is less than 500nm, small In 250nm, less than 150nm, less than 100nm, less than 95nm, less than 90nm, less than 85nm, less than 80nm, less than 75nm, be less than 70nm, be less than 65nm, be less than 60nm, be less than 55nm, be less than 50nm, be less than 45nm, be less than 40nm, be less than 35nm, be less than 30nm, Less than 25nm, be less than 20nm, be less than 15nm, be less than 10nm, be less than 5nm, be less than 2nm or be less than 1nm.

It, can be in any stage in the manufacturing method of conventional ceramic proppant in one or more exemplary embodiments Add conductive material.The manufacturing method of conventional ceramic proppant can be or including with No. 4,440,866 United States Patent (USP) (its whole It is open to be incorporated herein) described in construction it is similar with operation.It, can be in one or more exemplary embodiments Conductive material is added in any stage of the manufacturing method of drippage casting proppant.It is suitable to drip casting method and thus manufacture Proppant in No. 8,865,631 and No. 8,883,693 United States Patent (USP)s, the U.S. Patent application that publication No. is 2012/0227968 And it is disclosed in No. 14/502,483 U.S. Patent application (its entire disclosure is incorporated herein).

According to some embodiments of the present invention, conductive material is coated on proppant to provide conductive supporting agent.The coating Can by any paint-on technique well known in the art (for example, injection, sputtering, vacuum deposition, immersion coating, extrusion, calendering, Powder coating, plating, transfer coating, air knife coating, roller coating and brushing) it completes.In one or more exemplary embodiments, lead Electric material is coated in using electroless plating or painting method on proppant.

Conductive material can be combined in resin material.Ceramic proppant or natural sand, which can be coated with, includes conduction (metal cluster, sheet metal, metal ball, metal powder, nonmetallic, metal nanoparticle, quantum dot, carbon nanotube, Bark are quick for material This special fullerene and other suitable conductive materials) resin material to provide the proppant that contains and can be detected by calutron Conductive material.What the process for coating proppant and natural sand was well known to those skilled in the art.For example, It is described in No. 3,929,191 United States Patent (USP)s (its entire disclosure is incorporated herein) of Graham et al. suitable molten Agent coating procedure.Such as No. 3,492,147 United States Patent (USP)s in Young et al. (its entire disclosure is incorporated herein) Described in other suitable processes be related to having liquid, the particulate substrate of uncatalyzed resin component (it is characterized in that from water-soluble Liquid extracts the stability of catalyst or curing agent) coating.In addition, in 4,585, No. 064 United States Patent (USP) (its of Graham et al. Entire disclosure is incorporated herein) in describe for using phenol-formaldehyde novolaRs resin suitable hot melt Melt coating step.Other suitable methods familiar to the person skilled in the art for resin coating proppant and natural sand.

According to some embodiments of the present invention, conductive material is incorporated in resin material and ceramic proppant or natural sand Son is coated with the resin material containing conductive material.The process that proppant and natural sand are coated for resin is people in the art Member is known.For example, in 3,929, No. 191 United States Patent (USP)s (its entire disclosure is incorporated herein) of Graham et al. Describe suitable solvent coating procedure.For example, in 3,492, No. 147 United States Patent (USP)s of Young et al., (its entire disclosure passes through Reference be incorporated into herein) described in other suitable process be related to that there is liquid, the particulate substrate of uncatalyzed resin component The coating of (it is characterized in that from stability of extraction with aqueous solution catalyst or curing agent).In addition, the 4,585 of Graham et al., It is described in No. 064 United States Patent (USP) (its entire disclosure is incorporated herein) for utilizing phenol-formaldehyde novolaRs The suitable heat fusing coating step of resin.Its for being used for resin coating proppant and natural sand familiar to the person skilled in the art His suitable method.

According to several exemplary embodiments, proppant disclosed herein is coated with resin material to provide the branch of coated with resins Support agent particle.According to several exemplary embodiments, conductive material can mix with resin material and coated on proppant with The proppant particles of coated with resins are provided.According to several exemplary embodiments, the table of proppant particles of coated with resins each At least part in face region is covered by resin material.According to several exemplary embodiments, the proppant particles of coated with resins Surface region at least about 10%, at least about 25%, at least about 50%, at least about 75%, less than 90%, less than 95% or be less than 99% is coated by resin material.According to several exemplary embodiments, the pact of the surface region of the proppant particles of coated with resins 40% to about 90%, about 25% is covered to about 80% or about 10% to about 50% by resin material.According to several exemplary implementations Example, all surfaces region of the proppant particles of coated with resins is covered by resin material.For example, the proppant particles of coated with resins Resin material can be utilized to encapsulate.

According to several exemplary embodiments, any proper amount of resin material is present in the proppant particles of coated with resins On.According to several exemplary embodiments, the proppant particles of coated with resins include pressing for the proppant particles based on coated with resins Weight calculates at least about 0.1% resin, at least about 0.5% resin, at least about 1% resin, at least about 2% resin, at least about 4% Resin, at least about 6% resin, at least about 10% resin or at least about 20% resin.According to several exemplary embodiments, coating tree The proppant particles of fat include the proppant particles based on coated with resins calculate by weight about 0.01%, about 0.2%, about 0.8%, the resin of about 1.5%, about 2.5%, about 3.5% or about 5% to about 8%, about 15%, about 30%, about 50% or about 80%.

According to several exemplary embodiments, resin material includes any suitable resin.For example, resin material may include Phenolic resin, such as phenol-formaldehyde resin.According to several exemplary embodiments, phenol-formaldehyde resin has formaldehyde and phenol Molar ratio (F:P) from lower about 0.6:1, about 0.9:1 or about 1.2:1 to higher about 1.9:1, about 2.1:1, about 2.3:1 or About 2.8:1.For example, phenol-formaldehyde resin can be about 0.7 with the molar ratio of formaldehyde and phenol:1 to about 2.7:1, about 0.8: 1 to about 2.5:1, about 1:1 to about 2.4:1, about 1.1:1 to about 2.6:1 or about 1.3:1 to about 2:1.Phenol-formaldehyde resin may be used also It is about 0.8 with the molar ratio with formaldehyde and phenol:1 to about 0.9:1, about 0.9:1 to about 1:1, about 1:1 to about 1.1:1, about 1.1:1 to about 1.2:1, about 1.2:1 to about 1.3:1 or about 1.3:1 to about 1.4:1.

According to several exemplary embodiments, the molar ratio that phenol-formaldehyde resin has is less than 1:1, it is less than 0.9:1, it is less than 0.8:1, it is less than 0.7:1, it is less than 0.6:1 or be less than 0.5:1.For example, phenol-formaldehyde resin can be or including novolaks tree Fat.The known novolac resin of those skilled in the art, for example, see the 2 of Rankin, 675, No. 335 United States Patent (USP)s, Hanauye No. 4,179,429 United States Patent (USP)s, No. 5,218,038 United States Patent (USP)s of Johnson and Pullichola No. 8,399,597 U.S.s State's patent, entire disclosure are incorporated herein.The suitable examples of commercially available varnish gum include from Plenco^TMIt can It is the varnish gum of acquisition, retrievable from MomentiveResin and from the retrievable varnish gum of S.I. groups.

In one or more exemplary embodiments, conductive particle disclosed herein can inject the aperture of proppant particles In.For example, one or more conductive particles can inject in the porous structure of proppant particles, wherein after the conductive particle Applying coating, the coating allow conductive particle to be eluted from the aperture of proppant particles and lean against the outer surface of proppant particles At or near.Conductive particle can also be injected according to any suitable way disclosed in No. 14/629,004 U.S. Patent application Proppant particles are eluted from proppant particles.

Conductive particle can be in any suitable manner introduced into one or more subterranean fractures.For example, conductive particle It can be mixed with the mud of non-conductive support agent to provide conductive particle/non-conductive support agent composition at or near surface. Then, conductive particle/non-conductive support agent composition can introduce one or more ground during suitable hydraulic fracturing operations Conductive supporting agent is provided when at or near outer surface of the lower crack to lean against the proppant of proppant pack when conductive particle to fill Packing course, so that proppant pack is conductive.In one or more exemplary hydraulic fracturing operations, conductive particle and non-lead Any combinations of electric proppant can be introduced into one or more cracks to provide conductive supporting agent filling layer.

In one or more exemplary embodiments, handles and/or coat using one or more chemical substances or ligand Conductive particle is so that conductive particle has function of surface.These coatings can from containing different chain length material and/or organise It closes and is selected in the organic compound of object, each of which has the functional group on the end of its corresponding chain to change or customize manufacture Fluid in conductive particle dissolubility (dissolubility used herein further relates to suspension or mud).These coatings can also be from It material containing different chain length and/or is selected in the organic compound of organic compound, each of which has in its corresponding chain Functional group on end makes it has to be used to support proppant material in agent filling layer to change the function of surface of conductive particle Outer surface compatibility.These coatings can also be from the organic compound of material and/or organic compound containing different chain length It is selected in object, there is each of which the functional group on the end of its corresponding chain to make it with the function of surface for changing conductive particle The compatibility of resinous coat with the proppant for coated with resins.Many commercially available surfactants can be used for these Purpose.Multi-functional ligand is also used as coating, and one end of ligand molecular is joined to conductive particle and ligand molecular The other end influences the diffusivity of the conductive particle of entire proppant pack.It can be repaiied by traditional methodology of organic synthesis and principle Change multi-functional ligand to increased or decrease compatibility of the conductive particle to the outer surface of proppant in support unit.It can use The example of the type of functional group be carboxylate, amine, mercaptan, polysiloxanes, silane, alcohols and can be joined to conductive particle or Other types of proppant surface.At least part of conductive particle may remain in (one or more) of proppant pack At or near surface, this is because compared with (one or more) fracturing fluid and/or (one or more) manufacture fluid, it is conductive Particle has the compatibility of the bigger for the outer surface for being used to support resinous coat and/or proppant particles on agent particle.

Fig. 7 A show the created fractures 700 in open state 702 or pre-closed state, and it includes under the first load 704 Conductive supporting agent filling layer.In one or more exemplary embodiments, created fractures 700 can be from casing near normal Ground extends outwardly, wherein the casing in the casing, on the surface at or near casing and/or nearby well Current source in hole is electrically connected.In one or more exemplary embodiments, conductive supporting agent filling layer at the surface or One or more of neighbouring and/or one or more adjacent wellbores electric-field sensor and/or magnetic field sensor are electrically connected.One In a or multiple exemplary embodiments, crack 700 can be or fill crack 32 including proppant.For example, proppant filling is split Seam 32 may be at open state 702 and may include the conductive supporting agent filling layer under the first load 704.As herein It uses, term " open state " refers to crack before fracturing fluid leakage occurs when the release of the injection pressure of fracturing fluid And the situation of proppant pack wherein included.After abundance is revealed, crack will be closed so that crack is from open state 702 are converted to closed state.Fig. 7 B show the crack 700 in closed state 706 comprising the figure under the second load 708 The conductive supporting agent filling layer of 7A.As used in this article, term " closed state " refers to the injection due to discharging fracturing fluid Pressure and cause fracturing fluid reveal after, the situation of crack and proppant pack wherein included.

At least part of the electric current generated by source can advance and by crack from casing (such as casing 22) Proppant in 700.By in casing and travel to electromagnetic field that electric current in each position of earth volume generates can be by Existing conductive supporting agent filling layer changes after crack 700 is injected in conductive supporting agent.Such as it is sensed by well using sensor 38 Casing and the electric current traveled in proppant pack the two of each position in earth three-D volumes generate electromagnetic field.

It has been found that due to sealed fracture leads to the increase for being closed pressure or load on conductive supporting agent filling layer can be with Lead to the increase of the conductivity of conductive supporting agent filling layer.In one or more exemplary embodiments, conductive supporting agent filling Load in the group of layer increases the conductivity at least about 50%, at least about of 2 times, 5 times, the 10 times groups that can increase conductive supporting agent 75%, at least about 100%, at least about 150% or at least about 200%.In one or more exemplary embodiments, conductive supporting Load in the group of agent filling layer increase by the resistivity of 2 times, 5 times, the 10 times groups that can reduce conductive supporting agent filling layer 200 from About 1%, about 2% or about 5% to about 10%, about 15% or about 25%.

Furthermore, it has been found that the increase or change of the conductivity and/or resistivity of conductive supporting agent filling layer can be detected It surveys to determine crack closure and/or fracture closure times.In one or more exemplary embodiments, conductive supporting agent filling layer The change of conductivity and/or resistivity in one or more time intervals can be detected and be recorded to determine that crack is closed Conjunction and fracture closure times.It is further when being not observed in the conductivity and/or resistivity in conductive supporting agent filling layer When change, it may be determined that fracture closure times.For example, two or more, three or more, four or more, five or more Changing for conductivity in a proppant pack and/or resistivity is not detected in more or ten or more continuous time intervals Change then indicates crack closure.

The detection of the closure in crack and the determination of closing time will depend on a number of factors, including but not limited to, crack Net conductivity, crevice volume, around crack the earth and conductivity, magnetic permeability between crack and surface mount sensor And capacitivity.The net conductivity in crack refers to crack, proppant and fluid when crack, proppant and fluid are respectively positioned in the earth The combination of conductivity subtract the conductivity on big stratum in the absence of crack, proppant and fluid.In addition, proppant fills crack Total conductivity be that the conductivity generated by diaclase adds the conductivity of fluid plus the conductivity of new/modification proppant In addition the combination of electrokinesis of the mobile fluid Jing Guo porous bodies (such as proppant pack).It can be by making the height in crack Degree, length and width (that is, gap) multiplication determine the volume in the crack of the over-simplification with plane geometry form.It can use The wired difference electromagnetic calculation of three-dimensional (3D) of electromagnetism Maxwell equation is solved for numerical simulation.In order at the earth's surface It is able to detect that the electromagnetic response in the proppant filling crack at certain depth, (wherein, for Barnett shale original molds type Total crevice volume is close to 38m³), the net crack conductivity in a computing unit of wired difference (FD) grid is multiplied by crack Volume has to be larger than close to 100Sm².For Barnett shale original mold types, the depth in crack is 2000m.For numerical simulation These requirements can be converted to for the property in stratum rather than the application of the field of Barnett shale.

By electromagnetism Maxwell equation management by the propagation of electromagnetism (EM) wave field of three-dimensional (3D) geographical medium and/or Diffusion.

According to one embodiment of present invention, imaging method can be utilized (such as to be moved based on Maxwell equation and electromagnetism Move and/or holography inversion algorithm) analysis of Electromagnetic response measurement three-dimensional component with determine proppant pack position and Closing time around the crack of proppant pack.For determining proppant pack position and comprising proppant pack The inverting of the acquisition data of the closing time in crack is related to adjusting earth model parameter The net conductivity of proppant position and crack in seam) forward model for the response for assuming earth model is calculated with obtaining Preferably adaptation.Such as Bartel, L.C. is in SEG Technical Program Expanded Abstracts, 1994,361- Described in 364 Integral wave-migration method applied to electromagnetic data, Electromagnetism integrates wave moving method and utilizes Gauss theorem, wherein the data projection obtained on hole to subsurface is to form support The image of agent filling layer.In addition, such as Bartel, L.C. in SEG Technical Program Expanded Abstracts, The Application of EM Holographic Methods to Borehole Vertical of 1987,49-51 Described in Electric Source Data to Map a Fuel Oil Spill, electromagnetism holographic method is based on seismic holography Method and lean on constructive and destructive interference, wherein data and source waveform project in earth volume to form proppant pack The image of layer.Due to the longer wavelength responded for the low frequency electromagnetic of migration and holographic method, it is possible that needing to turn data It is changed to other shorter domains of wavelength.Such as Lee, A news of the K.H. et al. in the volume 54 the 9th of Geophysic (1989) Described in approach to modeling the electromagnetic response of conductive media , which is referred to as the domains q.In addition, such as Lee, K.H. et al. is in Lawrence Berkeley Lab, 1992 Tomographic Imaging of Electrical Conductivity Using Low-Frequency Electromagnetic Fields Described in, the wavelength shift when applying conversion.

In addition, combining the electromagnetism Maxwell of the constitutive relation with the isotropic medium for being suitable for being unrelated with the time The system that equation generates six coupling first order partial differential equations for being known as " EH " system.Title is derived from dependent variable wherein included, That is electric vector E and magnetic vector H.Coefficient in EH systems is three material characters, that is, conductivity, magnetic permeability and capacitivity.It is all These parameters can be with 3d space position change.The Inhomogeneous Terms of EH systems indicate each individual sources of electromagnetic wave and include passing Electrical conduction current source, magnetic induction source and displacement current source.Indicate the conduction electric current of the electric current flowing in electric wire, cable and wellbore Source is that an electromagnetic data obtains source most-often used in experiment.

In one or more exemplary embodiments, electric vector is directed to using explicit time-domain finite difference (TDFD) numerical method Three components of three components and magnetic vector H of measuring E solve EH systems using the function as position and time.It needs and can be with The three-dimensional grid expression (being known as " earth model ") of electromagnetic medium parameter is constructed by geophysical log and geological information can be obtained. Algorithm is also inputted for the size of current source, direction and waveform.Waveform can have pulse type shape (as in Gaussian pulse) Or can include the reciprocal square wave of both anode portion and cathode portion, but be not limited to both specific choices.Numerical value The execution of algorithm generates the electromagnetism of the time series form recorded on grid earth model or at the receiver position of interior distribution Response.These responses indicate three components or its time-derivative of E vector sum H-vectors.

When important modeling parameters change, the execution repeatedly of wired difference numerical algorithm makes it possible to quantitative estimation electromagnetism Size and the frequency composition (being measured in wellhole on or near at the earth's surface) of response.For example, the depth of current source can from compared with It is shallow to change into relatively deeply.Due to having charging wellbore, so current source can localize at certain point or can be space Extend transfer line.Source waveform can be broadband or narrowband in spectral composition.Finally, thus it is possible to vary electromagnetism earth model, to The screen effect of shallower conductive layer may be assessed.The purpose of this modeling activities is assessment record electromagnetic data in relevant parameter The sensibility of variable.Then the information obtains geometric figure for designing best field data, wherein the geometric figure has increased The strong possibility for certain depth proppant filling crack imaging.

Electroresponse and magnetic response can be scaled with input current size.In order to obtain the sound on background electromagnetic noise It answers, it may be necessary to the larger current of 10 to 100 order of amps.Cable will be true to the impedance of galvanic contact point and the earth contact resistance Surely expectation electric current required voltage is obtained.Wish that contact resistance is smaller and the contact resistance will not dominate required voltage.This Outside, it may be necessary to amount to many repetitions of measurement data to obtain measurable signal level on noise level.It is on the scene to answer With in modeling scene, temporal current source waveform can be used but be not limited to time domain waveform.Typical time domain waveform is by positive electricity The opening time of stream and shut-in time later and the opening time of negative current later are constituted.In other words ,+electric current, it After close ,-electric current is again switched off later.The repetition rate used by by reach the electric current opened before stable state how long when Between or field weaken as close to needing before zero to close how long supply current determines.In the illustrative methods, it will use Electric current open after the time field of rise, stable state numerical value and electric current close after the response that measures of decaying field analysis. The advantage that data are analyzed when supply current is zero (collapsing field) is to have eliminated main field contribution (from transmission conductor, that is, well Casing, response) and only measure the earth respond.In addition, the shut-in time section of time domain input signal allows analysis may be from The DC electric field of electrokinesis, including but not limited to, the streaming flow during rupture process and proppant.Measurement data will be passed through Inverting and/or the form of holographic reconstruction of earth part (crack) (it, which is generated, measures electroresponse or two level field) determine crack Property (orientation, length, volume, height and asymmetry).According to some embodiments, precracking investigation will be prepared be isolated due to Two level field caused by crack.It would be recognized by those skilled in the art that other for being used to analyze record electromagnetic data can also be used Technology, such as electric current source waveform and full waveform inversion using the electromagnetic data observed.

In one or more exemplary embodiments, using frequency domain wired difference (FDFD) numerical method to be directed to electric vector Three components of E and three components of magnetic vector H solve EH systems.For the earth model of current source, size, direction and waveform Algorithm can be inputted.Similar to TDFD numerical methods, waveform can have pulse type shape (such as in Gaussian pulse) or can To be to include the repetition square wave of both anode portion and cathode portion, but be not limited to both specific choices.Numerical algorithm Execute the electromagnetic response for generating the frequency series form recorded on grid earth model or at the receiver position of interior distribution.This A little responses indicate three components or its frequency dependence of E vector sum H-vectors.

In one or more exemplary embodiments, using polarization (IP) effect is induced to determine the position of proppant and contain The closing time in the crack of proppant.IP effects are present in time domain, wherein measure the effect after driving electric field stops. IP effects are also present in frequency domain, wherein the effect is illustrated in terms of complex impedance.For time domain measurement, when input current closes Function of the voltage attenuation received when closing as the time.Frequency in mutually decaying and receiving voltage of the frequency domain measurement from input current The effect of rate.

IP effects by extra electric field frequency a variety of causes and different dependences cause.Some theoretical cores are more Fluid flowing in the medium of hole.In porous media, thus the earth material typically somewhat micro-strip negative electrical charge is organized in pairs in attraction fluid The positively charged ion of electric layer (EDL).This makes the fluid in aperture space compare enrichment negative electrical charge, wherein the negative electrical charge Nowadays the electric current in porous media is guided.Ionic current is the difference of the concentration of cation and anion.Due to extra electric field, pressure Strong gradient and/or diffusion and the flowing for generating ion, wherein by the available aperture space of EDL limit transports.Additionally, there are can To cause other limitations (other materials in small pore throat, aperture space) of the charge accumulation for flowing.It is electronics conductor Metallic ore also influence the flowing of ion.When switching forces electric field, distribution of charges " desired " seeks lower energy state, That is, equilibrium condition.Being diffused in for charge is sought to play main function in acquisition balance.In other words, when submerging in aqueous solution Or when structure surface, from water to mutually being substantially change as this physical chemistry variable and electrolyte concentration of potential to other Interface, which is formed, interrupts.Due to the different chemical potentials between two-phase, so it occur frequently that separation of charge at interface zone.The boundary Face region and charging surface are known usually as EDL together.(it can extend in very dilute solution for the EDL or layer 100nm is remote and extends only several angstroms in dense solution) important work is played in electrochemistry, colloid science and surface chemistry With.

When conductive supporting agent have been placed in (one or more) crack and to casing for induced current when, electric field hangs down The component in crack is directly typically larger than parallel in the component in the direction in crack.The component for being parallel to crack of electric field will lead to crack Ionic conductivity in fluid, wherein ionic conductivity will be due to luring in ionic mobility present in EDL and conductive supporting agent Electricity lotus and it is hindered.In addition, there will be the electron stream flowings via the conductive supporting agent being in contact with each other.Perpendicular to crack Electric current by unobvious depend on electronics flow but be more dependent on proppant particles coat via metal electronics biography It leads.The electronics conduction of electric current will be depending on the volume of existing metal and will be dependent on the proppant that will be in contact with each other Grain.

If the time that supply current opens sufficient amount makes the movement of charge reach stable in existing application electric field State, then when the electric field of current-termination and application is zero, charge itself have to be redistributed to reach the charge of balance Distribution.This redistribution will not occur immediately, but be related to several attenuating mechanisms.Film IP effects can be imitated with electrode polarization It should occur together.At proppant surface or present on conductive coating can by with the relevant Rechargeability of surface impedance item And generate apparent IP responses.Surface impedance item will be with the characteristic of some Time-Dependents (or frequency).From conductive supporting agent The IP of particle is responded the total surface coated area depending on these proppant particles.For example, for having 700 micron diameters Proppant particles substrate on 1 micron of thick metal coating, the volume of metal coating is close to 15 × 10^-13m³And it each props up Support the surface area 1.54 × 10 of agent particle^-6m².For example, 75% packaging factor means per unit volume 4.14x 10⁹Proppant Particle, wherein every cubic metre of metal total volume is 0.0062m³And every cubic metre of total surface area is 6380m².The calculating indicates Coating IP effects caused by proppant particles by metal has the enhancing conductivity effects for being more than metal coating proppant particles Possibility.

Influence the induced response that other EM responses that IP is measured are the earth.The induced response in conducting medium by generating whirlpool The Faraday/Lentz laws of stream cause.Time change rate of the response based on magnetic field；If magnetic field increases, vortex exists It is generated in conductor (the earth) to build the magnetic field opposite with increased magnetic field, and if magnetic field reduces, is vortexed in the conductor It generates with the opposite magnetic field in the magnetic field for constructing with reducing.As a result, generating the response responded like IP, that is, in main magnetic field After opening (electric current unlatching), response spends the time to realize saturation and be rung after (electric current closing) is closed in main magnetic field Zero should be decayed at leisure.Greatly together, conductive fractures (fluid and proppant) will be generated except described above for conduction with surrounding IP response except induced response.Since electric field and magnetic field are coupled by Maxwell equation, so magnetic induction itself also exists Occur in electric field.Inductive effect and IP effects are additional.Due to its different frequency response, so the two responses can be in magnetic It is detached in.

In addition, including that induced response is responded without IP to the finite difference method FDEM of Maxwell equation.At one Or multiple exemplary embodiments this can, IP response can include by should be used as and put into practice relevant source item by IP phases In FDEM algorithms.If as IP effects are handled with relevant source item is put into practice, IP effects can be more than pure conduction response.

It, can be by by multiple or series of discrete electric current (a in one or more exemplary embodiments₁…a_N) introduce Crack determines the closure of the subterranean fracture of the agent containing conductive supporting.N may be greater than 1 any integer.For example, N can be 2, 3,4,5,6,7,8 or 9 or bigger.This series of electric current (a₁…a_N) it can correspond to a series of EM field measures (b₁…b_N) make Obtain b₁It is electric current a₁Measurement, b₂It is electric current a₂Measurement etc..It can iteratively compare and measure b_NTo b_N+1Determine that crack is closed The amount and/or degree of conjunction are to check the difference between two continuous measurements.It is continuous to measure b_NTo b_N+1Between there is no difference or It is substantially not present the closure that difference indicates crack.

It, can be by by multiple or series of discrete electric current (a in one or more exemplary embodiments₁…a_N) introduce Corresponding EM field measures (b in crack and acquisition at certain time intervals₁…b_N) determine the closure in crack.Time interval It can be or include the conductive supporting agent injection crack and by continuously measuring b containing mud_NAnd b_N+1Between there is no difference or do not have substantially The time interval of any selection between when the variant closure for indicating crack.From containing mud conductive supporting agent inject crack to It indicates continuous and measures b_NAnd b_N+1Between when not have difference or the time interval at substantially no difference moment can be the closure in crack Between.

Field data acquisition experiment is carried out to indicate with the transfer line in testing well casing current source.The electric field of calculating and the electricity of measurement Field is consistent well.The test indicates that the transmission electric line source implemented in 3D finite difference electromagnetic codes provides accurate result. Certainly, consistency depends on the accurate model of description magnetotelluric property.In the field data obtains experiment, common electricity is used Well logging indicates the feature of the electrical property of the earth around test wellhole and constructs earth model.

Including following example to indicate the illustrative examples of the present invention.Skilled artisans will appreciate that these examples Disclosed in technology be only it is illustrative and not restrictive.In fact, in view of the disclosure, those skilled in the art should lead Can in the case of not departing from the spirit and scope of the present invention, can be made in disclosed specific embodiment it is many variation and Still obtain same or analogous result.

Example 1

Relatively thin metal layer is coated on the ceramic proppant of Regular low density or intermediate density using RF magnetron sputterings, The ceramic proppant can be commercially available from the CARBO Ceramics companies of Texan Houston, and brand name is(CL)20/40、(HP or HYDROPROP) 40/80,20/40 and CARBOPROP 40/70.Three kinds of metal objects (that is, aluminium, copper and mickel) are for depositing.It uses 200W RF power, 5mTorr deposition pressures and 90sccm argon background flow rates are deposited in sputtering chamber.Sputtering chamber has There are the three articulated 2 inches of object retainers that can be used for coating complicated shape.The system also has to be sputtered downwards The rotation that is used in construction, water-cooled sample stage.Before coating proppant, by the way that metal sputtering on silicon and is surveyed Coating thickness (it is carried out by Zeiss Neon 40SEM Scanning Electrons microscope (SEM) cross-sectional analysis) is measured to determine for three The deposition rate of kind metal.

Proppant is loaded into a diameter of 12 inches of aluminium dish and the sputtering chamber with 1 inch of high side.It is close The proppant of 130g is run for coating every time.The proppant of the quantity substantially provides the single proppant stages in the substrate of disk. During deposition, use 6 inches of long filament " stirring " proppants, wherein the filament be suspended on disk and It is placed as contacting with the proppant in disk.Coat deposition time is by twice of silicon wafer coating thickness measurement so as to generally exist Then side coating proppant overturns it and coats the other side later.Summarize each in each type using three kinds of metals The coating of approximation 100nm and 500nm is deposited on the proppant of type.

After the coating process, visually and by light microscope proppant is checked.As a result indicate that there is approximation The proppant of the relatively shallow layer of 100nm usually has non-uniform coating, and has the proppant of the relatively thick coating of approximation 500nm Usually there is uniform coating.

The thickness that has that substrate support agent and different weight percentage are carried out using test device shown in Fig. 8 is 500nm's The electrical measurement of the mixture of this substrate support agent of aluminized coating.As shown in figure 8, test system 1000 includes being located at punching block 1006 In drilling 1004 (drilling 1004 with 1.0 inches of internal diameter) in insulating nitride boron mould 1002 (with 0.5 inch of internal diameter With 1.0 inches of outer diameter).With the rigid 1010 insertion insulation respectively of plunger of the upper steel plunger 1008 of 0.5 inch outer diameter and lower part The upper end 1012 and lower end 1014 of boron nitride mould 1002 so that room 1016 be formed in upper plunger 208 front end 1018, The front end 1020 of bottom plunger 1010 and the inner wall 1022 of boron nitride sleeve 1002.Top is removed from insulating nitride boron mould 1002 Plunger 1008 and proppant are loaded into room 1016 until proppant bed 1024 reaches the front end 1020 of bottom plunger 1010 On about 1 arrive 2cm height.Later, upper plunger 1008 is reinstalled in insulating nitride boron mould 1002 until upper plunger 1008 front end 1018 engages proppant 1024.Copper wire 1026 is connected to upper plunger 1008 and current source 1028 and voltage One pole of each of table 1030.Second copper wire is connected to bottom plunger 1010 and current source 1028 and voltmeter 1030 Another pole of each.Current source can be any suitable DC electric current source well known to those skilled in the art, for example, in DC 237 high-voltage power supply measuring units of Keithley (the 237 High Voltage Source of Keithley of current source mode Measurement Unit) and voltmeter can be any suitable voltmeter well known to those skilled in the art, for example, 175 True RMS multimeters of Fluke (175 True RMS Multimeter of Fluke), can be for certain samples DC millivolt patterns in and for being used in ohm table schema of high electrical resistance sample.

Make current source energization and determines the electricity of the test system 1000 with proppant bed 1024 in room 1016 later Resistance.Later, the resistance of proppant 1024 is measured using multimeter so that as the function of pressure, which uses upper plunger Pressure as electrode and is applied to proppant bed 1024 by both 1008 and bottom plunger 1010.Specifically, R=V/I, in room The numerical value measured when in 1016 with proppant bed 1024 subtract the system touched with plunger resistance and electricalresistivityρ= R*A/t, wherein A is the area occupied by proppant bed 1024 and t is between upper plunger 1008 and bottom plunger 1010 The thickness of proppant bed 1024.

As a result as follows：

Do not added the electrical measurement of the substrate support agent of any conductive material on sample at sample 100V DC, In, which is the wax-like proppant of 50% volume of the disk that boil down to nominal diameter is 1 inch and thickness is approximate 2mm. Using these numerical computations resistivity and using the measured resistivity for pure wax, following values is by drafting drill log (resistivity) and volume fraction proppant one of infer and are inferred as volume fraction：

CarboProp 40/70:2x 10¹²Ohm-cm

CarboProp 20/40:0.6x 10¹²Ohm-cm

CarboHydroProp:1.8x 10¹²Ohm-cm

CarboEconoProp:9x 10¹²Ohm-cm

It should be noted that the resistivity of the sample measured above is very high and is unsuitable for the detection in the present invention.

Example 2

It shows to carry out electrometric result using the test device shown in Fig. 8 in following table I and II.

Table I show for 500nm aluminized coatings CARBOLITE 20/40 and be not added with conductive material The data of CARBOLITE 20/40.For each sample shown in Table I, 3g specimen materials are placed in 0.5 inch of mould To provide 0.196 square inch of area.It is 5mA and is tested at room temperature for the electric current that each test applies.

Table I

Table II show for 500nm aluminized coatings HYDROPROP 40/80 and be not added with conductive material The data of HYDROPROP 40/80.For each sample shown in Table II, 3g specimen materials are placed on 0.5 inch of mould In to provide 0.196 square inch of area.It is 5mA and is tested at room temperature for the electric current that each test applies.

Table II

As can be from being observed Table I and II, regardless of coating or the relative quantity of uncoated proppant, proppant pack The resistivity of layer is tended to reduce with the increase for being closed pressure.In addition, with uncoated proppant relative quantity increase with And the relative quantity of coating proppant reduces, the resistivity of proppant pack greatly increases.Finally, 100% coated with aluminum is utilized Proppant realizes minimum specific resistance.Coating proppant and uncoated proppant cause without mixing less than 100% coated with aluminum The resistivity measurements of proppant.

Example 3

Also carry out the electrical measurement with the proppant of nickel coating and copper coating.

Result is shown in following table III and Fig. 9.Table III is shown for 20/40 Hes of CARBOLITE with nickel coating The data of CARBOLITE 20/40 with copper coating.Each sample, specimen material shown in Table III are placed on In 0.5 inch of mould.The voltage applied for each test is 0.005V.

Table III

Example 4

Also carry out the electrical measurement of the proppant of coating with different thickness.Result is shown in following table IV and Figure 10. Table IV is shown for the nickel coating with 0.27 micron, 0.50 micron, 0.96 micron, 2.47 microns and 3.91 micron thickness The data of CARBOLITE 20/40.A sample in Figure 10 aoxidized and thus for the exemplary purpose electric conductivity not Foot.Each sample shown in the Table IV, specimen material are placed in 0.5 inch of mould.Each test is applied Voltage be 0.01V.

Table IV

Example 5

The example is based on pre- in the measurement Flow Field Numerical for increasing to 5,000S/m from 1,000S/m for proppant conductivity The predictive example of phase variation.In this example, computer simulation uses the earth model of the observation comprising horizontal well.The simulation Two electric-field sensors of 80 meters (m) are injected and divided including 20 amperes of electric current.The simulation further includes utilizing nickel coating branch Support the simulation fracture area of the laboratory result of agent particle.

Figure 11 shows the pairs of electricity of the line on the horizontal section along the hoistway for extending to 2,500m from x=-2,500 The curve of the calculating voltage determined between field sensor.The horizontal section that distance x is parallel to hoistway extends.For the concrete model Operation, well head intersects at x=-1200 with x distances and object crack is at approximate x=-1000m.In terms of result of calculation Interval is 500m.After electric current injection, the peak value of induced response is observed at 0.04 second.

Figure 11 is shown, the response magnitude of more conductive supporting agent is less than big for the response of less conductive supporting agent It is small.The reason is that dual：(1) due to the electric conductivity of proppant, thus in proppant electromagnetic field size 5,000S/m is less than 1,000S/m of the proppant pack and difference is shown at surface, and (2) for the earphone electricity of 5,000S/m materials Magnetic induce field be more than for 1,000S/m materials this, and due to Lentz laws thus cause with conduction the earth in increase The opposite bigger of primary magnetic field field.These induced responses itself are shown as measuring the reduction of response.It is shown in following table V The analogue data used in Figure 11.

Table V

When as proppant in use, particle described herein can mode identical with common proppants handle.For example, Particle can with together with the other materials used in disruption treatments by sack or it is in bulk in the form of be transmitted to well site.It can use normal Equipment and technology are advised so that particle to be placed on as proppant in rock stratum.For example, particle is mixed with fracture fluid and is noted later Enter in the crack in rock stratum.

In the illustrative methods of shelly ground, hydraulic fluid is injected with being enough to open the rate in crack and pressure in rock stratum Rock stratum, and crack will be injected containing sintering, roughly circular and spheric granules fluid to be open situation by fracture support, In the fluid as described herein by slurrying and with one or more properties described herein.

Foregoing description and embodiment want without stint and illustrate the present invention.It should be appreciated that in the essence for not departing from the present invention Various modifications may be made in the case of god and range.

Claims

1. a kind of method for determining crack closure the described method comprises the following steps：

It powers to the casing of wellhole, described sleeve pipe is extended to from the surface of the earth in stratum, and the stratum has at least partly Crack filled with conductive supporting agent；

The first electric field response is measured to provide the first field measure at the surface or in adjacent wellbore in first time interval；

The second electric field response is measured at the surface or in the adjacent wellbore to provide second survey in the second time interval Magnitude；With

It is determined by the difference between first field measure and second field measure and is closed pressure in the conductive supporting agent Strong increase.

2. according to the method described in claim 1, wherein, it includes measure electromagnetic field response three to measure first electric field response Tie up (x, y and z) component.

3. according to the method described in claim 2, wherein, it includes measure electromagnetic field response three to measure second electric field response Tie up (x, y and z) component.

4. according to the method described in claim 3, further comprising the steps of：

Three or more time intervals measured at the surface or in the adjacent wellbore electromagnetic field response three-dimensional (x, Y and z) component are to provide three or more field measures；With

It is determined by the difference between each of three or more field measures and is closed pressure in the conductive supporting agent Increase.

5. according to the method described in claim 1, further comprising the steps of：

The conductive supporting agent is injected in the crack, and wherein, the conductive supporting agent includes conductive sintering, big Cause round and spheric granules；With

Before injecting the conductive supporting agent in the crack, by hydraulic fluid with described in being enough to open in the wellhole The rate and pressure in crack are injected in the wellhole.

6. according to the method described in claim 3, wherein, electromagnetic field response is measured in the surface or the adjacent wellbore The measurement of three-dimensional (x, y and z) component includes using to divide on the crack on said surface or nearby and at least partly The sensor array of cloth measures three-dimensional (x, y and z) component of electromagnetic field response.

7. according to the method described in claim 1, wherein, the increase of pressure is closed in the conductive supporting agent makes the conductive branch Support the conductivity increase at least about 50% of agent.

8. according to the method described in claim 4, further comprising the steps of：By basic between two continuous field measures of observation Indifference determines the closure in the crack.

9. according to the method described in claim 1, before obtaining first field measure, executes and solve for the electromagnetism The numerical simulation of the Maxwell equation of the electromagnetism of field, in the time response of the best input waveform of determination and application on the scene The record sensor array geometric figure used, wherein the numerical simulation is based on true by geophysical log and geological information Fixed earth model.

10. a kind of method for determining fracture closure times the described method comprises the following steps：

First electric current is introduced from the stratum that wellhole extends；

By three-dimensional (x, y for measuring the electromagnetic field response from first electric current at the surface of the earth or in adjacent wellbore And z) component obtains the first measured value；

Hydraulic fluid is injected with being enough to open the rate in the crack in the stratum and pressure in the stratum；

It will be injected in the crack containing conductive sintering, roughly circular and spheric granules fluid under the first pressure；

The second electric current is introduced ground at or near the sintering containing the conduction, roughly circular and spheric granules the crack Ball；

By the three-dimensional for measuring the electromagnetic field response from second electric current at the surface of the earth or in the adjacent wellbore (x, y and z) component obtains the second measured value；

Discharge first pressure；

Third electric current is introduced into the earth at or near the crack；

By the three-dimensional for measuring the electromagnetic field response from the third electric current at the surface of the earth or in the adjacent wellbore (x, y and z) component obtains third measured value；With

Determine the difference between first measured value and second measured value.

11. according to the method described in claim 10, wherein, when obtaining second measured value, the crack is in open shape State.

12. according to the method described in claim 10, further comprising the steps of：

Series of discrete electric current is injected into (a₁…a_N) at or near the crack introduce the earth, wherein N be greater than 3 it is any Integer, and a₁It is first electric current；With

By being measured in the surface of the earth or the adjacent wellbore (a is injected from the electric current₁…a_N) each electromagnetic field Three-dimensional (x, y and z) component of response is directed to (a₁…a_N) each discrete measured values (b₁…b_N), wherein b₁It is described First measured value.

13. according to the method for claim 12, further comprising the steps of：Iteratively compare measured value b_NAnd b_N+1To check two Difference between a continuous measurements, wherein by observing b_NAnd b_N+1Between substantially no difference determine closing for the crack It closes.

14. according to the method for claim 13, wherein b_N+1It is to work as to observe b_NAnd b_N+1Between substantially without difference when Final measured value, and, by calculating from the sintering that will contain the conduction, roughly circular and spheric granules fluid first It is injected under pressure in the crack to introducing electric current a_N+1Elapsed time determines fracture closure times.

15. according to the method described in claim 10, wherein, being calculated using from by the inverting of the Maxwell equation based on electromagnetism The three-dimensional component of the measured electromagnetic field response of imaging method analysis selected in method and the group of electromagnetism holographic method composition, with true Determine proppant pack position, wherein in the inversion algorithm, adjust the parameter of earth model to obtain a pair hypothesis earth mould The adaptation that multiple forward models of the response of type calculate, and wherein, in the electromagnetism holographic method, use constructive and destructive Interference projects electromagnetic field response and source waveform in earth volume to form the image of the proppant pack position.

16. according to the method described in claim 10, wherein, electromagnetic waveforms are selected from the group that Gauss, rectangular and time domain are constituted Using as input signal to generate three-dimensional electric field and magnetic responsiveness.

17. according to the method for claim 15, wherein before application on the scene, execute the electromagnetism solved for electromagnetic field Maxwell equation numerical simulation, used with the time response of the best input waveform of determination and in the field is applied Record sensor array geometric figure, wherein the numerical simulation is based on the ground determined by geophysical log and geological information Spherical model.

18. a kind of method for determining fracture closure times the described method comprises the following steps：

First electric current is introduced from the stratum that wellhole extends；

Discharge first pressure；

Series of discrete electric current is injected into (a₁…a_N) at or near the crack introduce the earth, wherein N be greater than 2 it is any Integer, and a₁It is first electric current；With

By being measured in the surface of the earth or the adjacent wellbore (a is injected from the electric current₁…a_N) each electromagnetism Three-dimensional (x, y and z) component of field response obtains (a₁…a_N) each discrete measured values (b₁…b_N)；With

19. according to the method for claim 18, further comprising the steps of：Iteratively compare measured value b_NAnd b_N+1To check two Difference between a continuous measurements, wherein by observing b_NAnd b_N+1Between substantially no difference determine closing for the crack It closes.

20. according to the method for claim 19, wherein b_N+1It is to work as to observe b_NAnd b_N+1Between substantially without difference when Final measured value, and, by calculating from the sintering that will contain the conduction, roughly circular and spheric granules fluid first It is injected under pressure in the crack to introducing electric current a_N+1Elapsed time determines fracture closure times.