Summary of the invention
The purpose of this invention is to provide a kind ofly with equipotential layer chromatographic imaging system and method between drilling well, cost is low, be easy to and existing oil field equipment compatibility, can utilize electrical method to solve the difficult problem that the well formation of oil field in exploration, development process distributes.
To achieve these goals, the present invention proposes following technical scheme:
1, a kind of with equipotential layer chromatographic imaging system between drilling well, the well formation that is used for the oil field is described test, comprising:
The signal transmitter unit, further comprise signal emission electrode, current-return electrode and sender unit, the three constitutes a complete circuit loop, wherein said signal emission electrode is positioned at by well logging, described signal emission electrode is connected with the transmitting terminal of described sender unit, described current-return electrode is connected with the return terminal of described sender unit, forms path;
Signal gathering unit further comprises interconnective signal receiving device and many group measuring points, and every group of described measuring point comprises M
n, COM
n, N
nThree terminals, wherein COM
nBe common port, n 〉=1, n is a natural number; Described some groups of measuring points are arranged in ground around described by well logging, are used to receive the N of many group measuring points
n-COM
n, M
n-COM
nBetween potential difference signal;
Signal processing unit, the described potential difference signal that transmission comes to signal gathering unit is handled;
Wherein said signal emission electrode adopts and creeps in described by the drilling rod in the well logging, along with creeping into of described drilling rod, described signal gathering unit obtains the described potential difference signal on different drilling depths stratum, and be transferred to described signal processing unit and handle, thereby obtain current potential tomographic map between described well of being logged well.
2, in the such scheme, the discharge position of described drilling rod is a drill bit, and described potential difference signal is corresponding to the stratum of the described drill bit place degree of depth.
3, in the such scheme, described current-return electrode and described by the design well depth of the distance between the well logging more than or equal to the described A that logged well.
4, in the such scheme, the supply lines of described drilling rod is connected on described preventer of being logged well or is connected on the metal manifold that is connected with described well head of being logged well; Described current-return electrode is one of following situation:
1. water injection well or producing well, wherein said water injection well or producing well are built-in with the sleeve pipe of good conductor material, its degree of depth near or surpass the described degree of depth of being logged well, the supply lines of described current-return electrode is connected on the wellhead assembly of described water injection well or producing well;
2. artificial electrode, described artificial electrode depth is more than or equal to the degree of depth of location shallow water face.
5, in the such scheme, described many group measuring points all have distribution in all directions of being logged well, and wherein encrypt on certain direction and arrange measuring point.
6, in the such scheme, described measuring point has 24 groups, and promptly n=24 is that the center of circle is evenly arranged ringwise with described well head of being logged well, in dividing, in, Wai Sanquan, wherein inner ring is 24 M
nTerminal, centre are interconnective 24 COM
nTerminal, outer ring are 24 N
nTerminal is used to test N
n-COM
n, M
n-COM
nBetween voltage.
7, in the such scheme, described signal processing unit comprises computer, described computer also is connected with described signal receiving device with described sender unit, the described sender unit of described computer control transmits to the stratum, and receives described potential difference signal on ground by described signal receiving device.
8, in the such scheme, the controllable signal transmitter of the energy loading pseudo random code of described sender unit employing Dagang Oilfield development, described signal receiving device adopts the controllable signal receiver of the energy loading pseudo random code of Dagang Oilfield development.
9, a kind of with current potential chromatography imaging method between drilling well, adopt and above-mentioned the well formation in oil field is described test with equipotential layer chromatographic imaging system between drilling well, wherein adopt creep in described by the drilling rod in the well logging as described signal emission electrode, along with creeping into of described drilling rod, described signal gathering unit obtains the described potential difference signal on different drilling depths stratum, and be transferred to described signal processing unit and handle, thereby obtain current potential tomographic map between described well of being logged well.
10, in the such scheme, the discharge position of described drilling rod is a drill bit, and described potential difference signal is corresponding to the stratum of the described drill bit place degree of depth.
11, in the such scheme, described current-return electrode and described by the design well depth of the distance between the well logging more than or equal to the described A that logged well.
12, in the such scheme, the supply lines of described drilling rod is connected on described preventer of being logged well or is connected on the metal manifold that is connected with described well head of being logged well; Described current-return electrode is one of following situation:
1. water injection well or producing well, wherein said water injection well or producing well are built-in with the sleeve pipe of good conductor material, its degree of depth near or surpass the described degree of depth of being logged well, the supply lines of described current-return electrode is connected on the wellhead assembly of described water injection well or producing well;
2. artificial electrode, described artificial electrode depth is more than or equal to the degree of depth of location shallow water face.
13, in the such scheme, described many group measuring points all have distribution in all directions of being logged well, and wherein encrypt on certain direction and arrange measuring point.
14, in the such scheme, described measuring point has 24 groups, and promptly n=24 is that the center of circle is evenly arranged ringwise with described well head of being logged well, in dividing, in, Wai Sanquan, wherein inner ring is 24 M
nTerminal, centre are interconnective 24 COM
nTerminal, outer ring are 24 N
nTerminal is used to test N
n-COM
n, M
n-COM
nBetween voltage.
15, in the such scheme, described signal processing unit comprises computer, described computer also is connected with described signal receiving device with described sender unit, the described sender unit of described computer control transmits to the stratum, and receives described potential difference signal on ground by described signal receiving device.
16, in the such scheme, the controllable signal transmitter of the energy loading pseudo random code of described sender unit employing Dagang Oilfield development, described signal receiving device adopts the controllable signal receiver of the energy loading pseudo random code of Dagang Oilfield development.
The chromatography imaging technique has between well of the present invention does not increase equipment cost, do not influence production, be easy to advantages such as realization.Through overtesting, the present invention successfully solves wellfracturing well fracture orientation, water injection well waterline direction of propulsion, the evaluation of profile control well profile control effect, steam and drives the technical barrier that well vapour drives direction and involves aspects such as scope, have remarkable advantages for the non-homogeneity of judging the oilfield development process midplane, will have important directive significance and wide application prospect oil field development work from now on.
The specific embodiment
The present invention is described in detail below in conjunction with accompanying drawing.But what those skilled in the art should know is to the invention is not restricted to the listed specific embodiment, as long as spirit according to the invention all should be included in protection scope of the present invention.
In problems such as fixed electrode condition lower leaf ability are low, the present invention carries out electrical survey between well to drilling rod as a current electrode in drilling process at electrical prospecting of the prior art, thereby solves the problem of vertical resolution.Promptly in drilling process, in well, constantly deepen, utilize drilling rod to power to the stratum, around wellhole, will form an artificial electric field that changes with drilling depth as a current electrode with drilling rod.Adopt the variation of detection system continuous monitoring its current potential in a distance around drilling well this moment, can reach the purpose of explaining resistivity profile between well.Therefore, in drilling process, the resistivity distribution situation on the stratum of any degree of depth that the present invention can reach drilling rod detects in real time, thereby solved description work to reservoir development stability, connectedness and non-homogeneity, related data (as: well-log information, oil field development dynamic data etc.) in conjunction with other can form sxemiquantitative and even quantitative explanation.Drilling rod of the present invention can comprise the drilling assembly of using in the drilling well in a broad sense, and as kelly bar, drill collar, drill bit etc., they all are metal materials, are good conductor.The discharge position of drilling rod can be arranged on the optional position of the drilling rod of below ground, is first-selected position with drilling rod drill bit bottom especially.
Fig. 1 is that the present invention is with equipotential layer chromatographic imaging system schematic diagram between drilling well.A is for to be logged well among Fig. 1, and electrode B is a current-return electrode, electrode B be used for and the A well between form current loop.Drilling rod 100 creeps into L in by well logging A
1, L
2, L
3..., L
nBe that its degree of depth is respectively h with drilling rod 100 residing Different Strata of drill bit when constantly being crept among the A by well logging
1, h
2, h
3..., h
nAlong with degree of depth h
nDifference, formation resistivity difference, M
1, COM
1, N
1Be one group of measuring point, be used to detect M
1With COM
1And N
1With COM
1Between the current potential difference, COM wherein
1It is common port; System of the present invention comprises the such measuring point of n group, M as shown in Figure 1
2, COM
2, N
2... M
n, COM
n, N
n,, wherein n is a natural number.
As shown in Figure 1, being logged well is provided with sender unit 200 between A and the current-return electrode B, and sender unit 200 is to the stratum of a certain degree of depth L
nA signal of telecommunication is provided, this signal is the signal of telecommunication with certain feature, such as being the pseudorandomcode signal, it also can be electric current with certain frequency, drilling rod 100 itself be exactly current electrode be the signal emission electrode, drilling rod 100 is generally all made by good conductors such as metals, and the signal of telecommunication is supplied with stratum L by drilling rod 100
n, and along with drilling rod 100 is constantly deepened in drilling process, to the stratum L of any degree of depth
nAnalyze.
Sender unit 200, drilling rod 100 and current-return electrode B have formed a current loop, and respectively organize ground signal test point M
n, COM
n, N
nThen be used for receiving on the ground the signal of telecommunication of diverse location for the A well, so just can realize a certain stratum L in the A well
nTest.Along with creeping into of drilling rod 100, degree of depth h
nIncrease, just can obtain the stratum L of any degree of depth
nSignal.
By collecting the ground signal data and handling, just can obtain different depth stratum signal of telecommunication characteristic, obtain current potential tomographic map between well in conjunction with other related datas, just can reach the purpose of describing the well formation characteristic distributions.For example: when adopting resistivity well logging, think resistivity high be oil reservoir, what resistivity was low is water layer; When adopting the self-potential method well logging, think current potential high be oil reservoir, what current potential was low is water layer.
More than be explanation of the principles of the present invention, be described further by specific embodiment below in conjunction with accompanying drawing.
Of the present inventionly comprise with lower unit with equipotential layer chromatographic imaging system between drilling well:
One, signal transmitter unit
Signal transmitter unit of the present invention comprises signal emission electrode, current-return electrode B and sender unit 200, and sender unit 200 is installed between signal emission electrode and the current-return electrode B, and the three constitutes a complete circuit loop.
Please also refer to Fig. 1 and Fig. 2.Fig. 2 is the connection diagram of being logged well of a specific embodiment of the present invention and current-return electrode, and wherein the A well is logged well, and B is a current-return electrode, and distance is D between A, the B, and the design well depth of the A that logged well is H.Require distance D between A, the B more than or equal to 1/2H, be preferably greater than or near H.Purpose is to form uniform electric field between A, B, convenient analysis to electric field.
The present invention utilizes drilling rod 100 as the signal emission electrode, and it is described that its operating principle sees preamble for details.
Requirement for electrode B is: can be the form of water injection well, producing well or artificial electrode, and preferred water injection well, producing well.If artificial electrode then requires the degree of depth of its degree of depth more than or equal to this area's shallow water face.Only be that example describes with the producing well below the present invention, " B well " in the literary composition promptly refers to electrode B.If the words of water injection well, producing well, the sleeve pipe that needs good conductor materials such as built-in metal, the effect of sleeve pipe is to use as an electrode, and should make as far as possible the B well the degree of depth near or surpass the degree of depth of A well, so that between A, B well, form uniform electric field, convenient analysis as far as possible to electric field.
Drilling rod 100 emissions that sender unit 200 is responsible in the A well have the signal of telecommunication of certain feature, as have loaded the signal of telecommunication of pseudorandomcode; In a preferred embodiment of the invention, sender unit 200 has adopted the controllable signal transmitter (applying for a patent separately) that DDPI-EMT that Dagang Oilfield develops voluntarily can loading pseudo random code.The controllable signal transmitter technical indicator of DDPI-EMT energy loading pseudo random code is as follows:
1,1 grade every ampere of maximum output current: 20A;
2, precision of steady current: ± 0.5%FS (load variations 10%);
3, crystal frequency stability: 0.01%;
4, output voltage: 50V, 100V, 150V, 200V, 250V, 300V, 350V, 400V, 450V, 500V, 550V, 600V;
0.1,0.3,1.0,3.0Hz 6, frequency:;
7, time domain pulsewidth: 1,2,4,8,16,32 seconds and direct current ± to;
8, this system can accept outer Synchronization Control (pseudo noise code);
9, anti-seismic performance is carried out by national field apparatus standard;
10, various safeguard measures are complete, and protective effect is arranged when undercurrent, overcurrent, overtemperature, overvoltage.
In actual applications, the connection of each parts of signal transmitter unit of the present invention need be carried out according to following steps:
(1) at first, drilling rod in the A well 100 is connected supply lines, drilling rod 100 itself is exactly a current electrode, in a specific embodiment, supply lines can be connected on preventer or be connected on the metal manifold that is connected with well head, whether be 0, be interconnected to guarantee stratum, supply lines and drilling rod 100 if needing with the megger test resistance then.
(2) secondly, electrode B and supply lines are coupled together: supply lines is connected on the wellhead assembly of B well, for example can be connected on the oil pipe or sleeve valve of production tree of B well.Whether after connecting, needing with megger test test resistance is 0, to be interconnected between assurance stratum, supply lines and the B casing.
(3) supply lines that will be connected with A, B well respectively with sender unit 200 be connected, wherein A is connected with the transmitting terminal of sender unit 200, B is connected with the return terminal of sender unit 200, forms path.
Two, signal gathering unit
Signal gathering unit comprises signal receiving device (not shown) and some groups of measuring points, and both interconnect, and signal receiving device is responsible for receiving the ground signal that some groups of measuring point transmission come.In a preferred embodiment of the invention, in order to guarantee required precision, the controllable signal receiver (applying for a patent separately) of the DDPI-EMR energy loading pseudo random code that signal receiving device employing Dagang Oilfield is developed voluntarily.
Some groups of measuring points are M shown in Figure 1
1, COM
1, N
1, M
2, COM
2, N
2... M
n, COM
n, N
n, these some groups of measuring points are arranged in ground around described by well logging A, are used to receive the signal of telecommunication of Different Ground position for the A well, so just can realize a certain stratum L in the A well
nData acquisition.
Fig. 3 is the ground measuring point theoretical deposition mode schematic diagram of one embodiment of the invention; In Fig. 3, the ground measuring point is that the center of circle circularizes and is radial even layout with the A well idealizedly, and can carry out the ground measuring point according to the density of required precision and be circular layout.And in real work, of the present inventionly can carry out irregular layout (as shown in Figure 4) according to lineament with equipotential layer chromatographic imaging system between drilling well, Fig. 4 is the schematic diagram that the actual at the scene measuring point of one embodiment of the invention is arranged, be the origin of coordinates by well logging A wherein, transverse axis is represented A, B well line direction, and the longitudinal axis is represented and A, direction that B well line is vertical, parasang is a rice, " ● " represents point position, and every group of measuring point includes three " ● ", is respectively M
1, COM
1, N
1, M
2, COM
2, N
2... until M
n, COM
n, N
nCommon port COM wherein
1, COM
2... with COM
nBetween be interconnected, for example can interconnect by cable.Each distribution of organizing measuring point should as far as possible guarantee to be logged well all directions of A all have distribution, can suitably encrypt the layout measuring point on certain emphasis direction, for example two groups of measuring point M among Fig. 4
2, COM
2, N
2, with M
3, COM
3, N
3All be arranged in same direction substantially.
Get back among the embodiment of Fig. 3, the expression of A point is logged well, B point expression electric current returns well, interconnect by electricity cable between A well and the B well, sender unit 200 has been installed between A, B, sender unit 200 is responsible for having the signal of telecommunication of certain feature to the emission of A well, as has loaded the signal of telecommunication of pseudorandomcode; Around the A well 24 groups of measuring points that have been circular layout, in dividing, in, Wai Sanquan, be that the center of circle evenly distributes ringwise with A, wherein inner ring is that 24 M terminals, middle solid line are that COM terminal, outer ring are 24 N terminals, be called interior, in, external terminal, be used to test N
n-COM
n, M
n-COM
nBetween voltage.The N of these 24 groups of measuring point transmission
n-COM
n, M
n-COM
nBetween potential difference signal be transferred to signal receiving device, such as DDPI-EMR can loading pseudo random code controllable signal receiver.
Certainly measuring point also can adopt other arrangements to arrange such as multi-turn in other embodiments, and the quantity of measuring point group also can be other natural numbers.
Three, signal processing unit (not shown)
The effect of signal processing unit is the N of 24 groups of measuring points that transmission comes to signal gathering unit
n-COM
n, M
n-COM
nBetween potential difference signal and related data handle, signal processing unit generally adopts computer, but also can adopt signal handling equipments such as single-chip microcomputer among other embodiment.
Many groups potential difference signal that signal gathering unit generates is delivered to computer and is handled, at last again further combined with other related datas, formation just can reach reservoir development stability, connectedness and non-homogeneity purpose of description the current potential tomographic map on a certain stratum.Because these contents belong to this area routine techniques, repeat no more.
In the preferred embodiment of the present invention, the controllable signal transmitter of the DDPI-EMT energy loading pseudo random code that sender unit 200 employing Dagang Oilfields are developed voluntarily, the controllable signal receiver of the DDPI-EMR energy loading pseudo random code that signal receiving device employing Dagang Oilfield is developed voluntarily, the controllable signal receiver of DDPI-EMR energy loading pseudo random code all links to each other with computer with the controllable signal transmitter of the DDPI-EMT energy loading pseudo random code of sender unit 200, and this computer can be shared with signal processing unit, be that computer control signal emitter 200 transmits to the stratum, and receive corresponding signal on ground, and simultaneously signal is processed and displayed by the controllable signal receiver that DDPI-EMR can loading pseudo random code.
In actual applications, of the present inventionly having obtained initial success with equipotential layer chromatographic imaging system and method between drilling well, is the test curve and the preliminary comparison diagram of log of one embodiment of the invention as Fig. 5.Transverse axis is represented the size of various signal amplitudes, and the longitudinal axis is represented by the degree of depth h of well logging A
n, wherein the test curve on Fig. 5 left side is meant a certain group of measuring point M of the present invention
n, COM
n, N
nThe acquisition curve of potential difference signal; And four logs on the right are meant the various curves that obtain with the conventionally test method, RA25 wherein, and RA4 is the resistivity measurement curve; SP is a spontaneous potential curve; AC is the sonic test curve.
Can obviously find out to the preliminary comparison diagram of log from the test curve of Fig. 5: test curve of the present invention is similar to the conventionally test tracing pattern, can both measure stratigraphic categories equally with routine techniques, realize extension by borehole wall measuring technology test technology between well.
It should be noted that the foregoing description is example and unrestricted the present invention, those skilled in the art can design a lot of alternate embodiments and not break away from the scope of appended claims.