CN112483077B - Method for identifying offshore ultra-low resistance oil layer by using gas logging data - Google Patents
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Abstract
The invention provides a method for identifying an offshore ultra-low resistance oil layer by using gas logging data, which comprises four steps of single well standardized correction, interwell normalized correction, hydrocarbon gas abundance curve oil layer threshold value determination, screening of a suspected ultra-low resistance oil layer and investigation of false marks, and the suspected ultra-low resistance oil layer is verified by means of old well hole repairing, sampling and the like, so that the problem that no take over reserve is generated in the middle and later stages of oil field development is effectively relieved; the method is that under the condition that the resistivity logging can not identify the ultra-low resistance oil layer, the gas logging data is systematically corrected, and the hydrocarbon gas abundance curve obtained by the method is used for more accurately and quantitatively identifying the ultra-low resistance oil layer.
Description
Technical Field
The invention belongs to oil and gas exploration and development, and particularly relates to a method for identifying an offshore ultra-low resistance oil layer by using gas logging data.
Background
Currently, the known low-resistance oil layer has near hundred million tons of geological reserves, accounting for one third of the geological reserves of the whole oil field group, and has great development value. However, the identification of extremely low-resistance oil reservoirs distributed in the stratum is a worldwide problem, and particularly offshore oil fields are limited by conditions, so that the identification difficulty is higher. As shown in FIG. 1, cao Feidian 11-2 is a ceramic group in an oilfield, and under the condition that formation fluid cannot be distinguished by resistivity logging, the oilfield is identified and confirmed by data such as nuclear magnetic logging, coring, MTD sampling, DST testing and the like in the exploration stage, and part of the ultralow-resistance oil layer is omitted due to technical limitations. The existing method for identifying the ultra-low-resistance oil layer has high cost and low success rate, is limited to the exploration and evaluation stage of the offshore oil field, and has no economic and effective technical means at the development stage of the offshore oil field. Accordingly, improvements are needed.
Disclosure of Invention
The invention aims to provide a method for identifying an offshore ultra-low resistance oil layer by using gas logging data, which aims to solve the technical problem that the accuracy of identifying formation fluid by resistivity in the ultra-low resistance oil layer is reduced.
In order to achieve the above purpose, the specific technical scheme of the method for identifying the offshore ultra-low resistance oil layer by using the gas logging data of the invention is as follows:
a method for identifying an offshore ultra-low resistivity reservoir using gas logging data, comprising the steps of:
firstly, single well standardization correction is carried out, wherein the single well standardization correction is based on a gas measurement total quantity curve in a gas logging curve, and the influences of formation pressure, drilling fluid pressure, drilling speed, dissolved gas-oil ratio and drill bit diameter change in the single well range on gas logging data are eliminated through formula calculation, so that a hydrocarbon gas abundance curve of the single well is obtained;
secondly, interwell normalization correction, namely selecting a large section of water layer section or mudstone section in the oil field range as a standard layer, unifying hydrocarbon gas abundance base values of all wells through multiple operation, eliminating systematic errors, and enabling hydrocarbon gas abundance curves of all wells to carry out fluid identification under unified standards;
thirdly, determining a threshold value of an oil layer of a hydrocarbon gas abundance curve;
and fourthly, screening suspected ultra-low resistance oil layers and checking false images, screening out a small amount of important suspected low resistance oil layers, verifying the oil content of the suspected ultra-low resistance oil layers by means of hole filling, sampling and the like, and completing the identification of the offshore ultra-low resistance oil layers.
The method for identifying the offshore ultra-low resistivity reservoir by using the gas logging data, wherein,
the formula adopted in the first step is as follows:
Ao＝TG/ΔP/ROP/GOR (1)
in the formula (1): ao is a hydrocarbon gas abundance curve, TG is a gas measurement total curve, Δp is a pressure difference curve between hydrostatic drilling pressure and formation pressure, ROP is a drilling rate curve, and GOR is a dissolved gas-oil ratio curve of each layer;
the normalization correction between wells in the second step is based on analysis of various influencing factors in the previous step, and systematic errors are caused between wells by partial drilling factors and logging factors in the drilling process, wherein the systematic errors comprise different sensitivity degrees of different logging recording instruments, different initial settings and different logging values recorded under the same condition; in order to eliminate the influence of the factors, on the basis of the hydrocarbon gas abundance curve obtained in the last step, a large-section water layer section in a depth range is selected as a standard layer, hydrocarbon gas abundance base values of all wells are unified through multiple operation, system errors such as drill bit diameter, slurry density, viscosity, instruments and the like are eliminated, system correction of the hydrocarbon gas abundance curve of each single well is completed, and fluid identification and residual oil saturation calculation are carried out on all wells under unified standards; for single gas and recycle gas factors which are difficult to correct, when a relative hydrocarbon gas abundance curve is applied, checking in a gas logging abnormal well section through the characteristic combination of the single gas and recycle gas factors in the area;
the third step of hydrocarbon gas abundance curve threshold value determination is to determine a hydrocarbon gas abundance curve threshold value of a known oil layer through data statistics and analysis, wherein the threshold value is the lowest value, and well sections with hydrocarbon gas abundance curve values higher than the threshold value are searched for in other positions in the oil field through the threshold value and serve as preliminary suspected targets;
and the fourth step of screening the suspected ultra-low resistance oil layer and checking the false image is to judge that the suspected target is the suspected ultra-low resistance oil layer or the false image according to the formation mode of the same layer of the oil field and the peripheral similar area, so that a small amount of important suspected low resistance oil layer is screened out, the oil content of the suspected ultra-low resistance oil layer is verified through hole filling and sampling, and the identification of the offshore ultra-low resistance oil layer is completed.
The method for identifying the offshore ultra-low resistance oil layer by using the gas logging data has the beneficial effects that: according to the method, in view of the fact that the accuracy of identifying formation fluid by resistivity in the ultra-low-resistance oil layer is greatly reduced, gas logging data is unaffected, on the basis of fully analyzing the sensitivity of various data in a local area to the oil layer, the gas logging data is selected as a main research target, and an economic and effective method for identifying the offshore ultra-low-resistance oil layer by using the gas logging data is formed by carrying out operations such as hydrocarbon gas component content and distribution in the oil layer, gas logging influence factors, a gas logging data correction method, a low-resistance oil layer discrimination standard based on the gas logging data and the like.
Drawings
FIG. 1 is a cross-sectional view of a well connection of a very low resistance reservoir of a conventional Cao Feidian 11-2 field banked ceramic group.
FIG. 2 is a schematic diagram of a normalized hydrocarbon gas abundance correction procedure of the present invention.
FIG. 3 is a cross-sectional view of an embodiment of the invention in a well connection with a very low resistance oil layer in a Cao Feidian-2 field collection of ceramics.
Detailed Description
For a better understanding of the objects, structures and functions of the present invention, the method of identifying an offshore ultra low resistivity reservoir using gas logging data is described in further detail below with reference to the accompanying drawings.
The influence factors of the gas logging curve mainly comprise four aspects of stratum factors, drilling factors, operation factors and logging factors. Because of these factors, gas logging data represents, in a strict sense, the concentration of hydrocarbon gas detected by the instrument when drilling fluid at the bottom of the well is circulated to the top of the well, and cannot represent the true concentration of hydrocarbon gas in the formation. In order to make the gas logging data have unified standard for judging fluid properties and quantitatively calculate the saturation of residual oil, the influence of the factors needs to be eliminated, and the gas logging curve is corrected into a hydrocarbon gas abundance curve capable of indicating the underground natural gas content.
In the process of calculating the hydrocarbon gas abundance curve, the above factors are analyzed first, and different correction methods are adopted for different factors of the generation mechanism and influence range. Some factors affect well sections with different depths in a single well, such as drilling speed, pressure difference and the like, and the factors need to be corrected in the single well; some factors cause interwell differences, such as mud density, bit diameter, which need to be normalized between wells; while some factors are affected by specific operations, only certain specific depths result in artifacts of gas measurement anomalies, which are difficult to correct, and these artifacts need to be examined in conjunction with geologic patterns (table 1).
TABLE 1 statistical table of air test data influencing factor classification and correction method
In the process of calculating the hydrocarbon gas abundance curve, the above factors are analyzed first, and different correction methods are adopted for different factors of the generation mechanism and influence range. Some factors affect well sections with different depths in a single well, such as drilling speed, pressure difference and the like, and the factors need to be corrected in the single well; some factors cause interwell differences, such as mud density, bit diameter, which need to be normalized between wells; some factors are affected by specific operations, and only certain specific depths cause gas detection abnormal artifacts, which are difficult to correct and need to be examined in combination with geological modes.
By comprehensively considering the factors, the embodiment of the invention corrects the gas measurement data and judges the potential ultra-low resistance oil layer by the following four steps:
the first step is single well standardized calibration. Based on the previous analysis of the various influencing factors, there were differences in some of the formation factors and drilling factors at different depths during the drilling process (table 1). If the pressure difference between the formation pressure and the static pressure of the drilling fluid is larger, the more formation hydrocarbon gas is diffused into the drilling fluid in unit time, the higher the gas measurement display value is, so that a certain deviation exists between the gas measurement display value and the actual formation hydrocarbon gas concentration; the larger the drilling speed is in the drilling process, the more stratum hydrocarbon gas is introduced into the drilling fluid in unit time due to rock breaking, the higher the gas measurement display value is, and the change of the drilling speed can have a great influence on the gas logging value. In order to eliminate the influence of the factors, the invention calculates the hydrocarbon gas abundance curve of a single well through the following formula on the basis of the gas measurement total logging curve, eliminates the influence of different depths of gas-oil ratio, pressure difference and drilling speed in the single well, eliminates the influence of the change of formation pressure, drilling fluid pressure, drilling speed, dissolved gas-oil ratio and drill bit diameter in the single well range on the gas measurement logging data, and obtains the hydrocarbon gas abundance curve of the single well;
Ao＝TG/ΔP/ROP/GOR (1)
in the formula (1): ao is a hydrocarbon gas abundance curve, TG is a gas measurement total curve, Δp is a pressure differential curve between hydrostatic drilling pressure and formation pressure,
ROP is the drilling rate curve, GOR is the dissolved gas oil ratio curve of each layer.
The second step is interwell normalization correction. According to the analysis of various influencing factors before, part of drilling factors and logging factors in the drilling process cause systematic errors among wells. If the sensitivity of different logging instruments is different and the initial setting is different, the logging values of the gas logging recorded under the same condition are different. In order to eliminate the influence of the factors, on the basis of the hydrocarbon gas abundance curve obtained in the last step, a large-section water layer section in the depth range of the librarian group is selected as a standard layer, the hydrocarbon gas abundance base value of each well is unified through multiple operation, the systematic errors of the diameter of a drill bit, the slurry density, the viscosity, an instrument and the like are eliminated, the systematic correction of each single-well hydrocarbon gas abundance curve is completed, and each well is subjected to fluid identification and residual oil saturation calculation under the unified standard. It should be noted that for single gas, recycle gas, etc. factors that are difficult to correct, when using the relative hydrocarbon gas abundance curve, the investigation should be performed in the gas logging anomaly well section by its characteristic combination with the reservoir pattern of the zone.
The third step is the determination of the hydrocarbon gas abundance curve threshold. And determining a threshold (lowest value) of the hydrocarbon gas abundance curve of the known oil layer through data statistics and analysis, and searching well sections with hydrocarbon gas abundance curve values higher than the threshold at other positions in the oil field through the threshold as preliminary suspected targets.
And the fourth step is screening of suspected ultra-low resistance oil layers and investigation of false images. And judging the suspected target as a suspected ultralow-resistance oil layer or an artifact according to the reservoir forming mode of the same layer of the oil field and the similar region around the oil field. For example, the top of a thick layer sandstone of a clay group in a Cao Feidian oilfield group is usually developed with an 'oil cap', and if a plurality of openings are adjacent to the top of the same sand body, the hydrocarbon gas abundance curves of the openings are all obviously higher than a threshold value, and the substantially consistent interface depth is reflected, so that the suspected ultra-low resistance oil layer can be preliminarily judged according to a reservoir forming mode; if the abundance of hydrocarbon gas in a certain sand body is abnormal, but the abundance of hydrocarbon gas is not consistent with the reservoir formation mode, and the adjacent well does not have the phenomenon, the abundance of hydrocarbon gas is considered to be false abnormality caused by specific operation processes such as single gas, post-effect gas and the like in the drilling process, so that a small amount of important suspected low-resistance oil layers can be screened out, and the oil content of the oil layers can be verified in modes such as hole returning and sampling.
Taking Cao Feidian-2 oil field liberal pottery group as an example, the oil field liberal pottery group is considered to develop only 1-1382 and 1-1400 sets of extremely low-resistance oil layers, the resistivity is 3.5Ω·m, the resistivity is equivalent to that of a water layer, and other layers are considered to be water layers, as shown in fig. 1. The method is applied to review old wells of the well ceramic group in the oil field, and the gas measurement total quantity curves of all wells in the oil field are sequentially subjected to single well standardized correction and interwell standardized correction according to the method to obtain standard hydrocarbon gas abundance curves of all wells. Through data analysis, under the condition that the hydrocarbon gas abundance base value of the large water layer of the oil field ceramic group is 2000ppm, the hydrocarbon gas abundance threshold value of the oil layer of the ultra-low resistance oil layers 1-1382 and 1-1400 sand bodies is 28000ppm, as shown in figure 2. Through well connection comparison, the hydrocarbon gas abundance value of the oil field multi-well at the top of the 1-1410 sand body below the known ultra-low resistance oil layer 1-1382 and 1-1400 sand body is higher than a threshold value, is a suspected construction bottom water reservoir, accords with the reservoir formation mode of the ceramic group ultra-low resistance oil layer in the oil field, and is a key verification target. And 12 months in 2018, performing hole repairing test on the clay body 1-1410 of the oil field librarian group through a Cao Feidian 11-2 oil field A28H well. The layer of hole complement produces pure oil and shows higher productivity, which confirms the accuracy and the practicability of the method and increases 300 square geological reserves for oil fields, as shown in figure 3.
The method is widely applied to the Bohai sea Cao Feidian oil field group and peripheral oil fields, a plurality of extremely low-resistance oil layers are proved at present, the geological reserve of the crude oil is proved to be more than 2000 ten thousand tons for the Bohai sea oil field, good development effect is obtained, and the problem that the reserve is not replaced in the middle and later stages of oil field development is effectively solved.
The content not described in this embodiment is the prior art, so that the description is not repeated.
The core technology of the method for identifying the offshore ultra-low resistance oil layer by using the gas logging data is a four-step method for correcting an original gas logging curve into a hydrocarbon gas abundance curve, and plays a core and key role in the technical scheme of the invention. The method is characterized in that under the condition that the resistivity logging curve cannot identify the ultra-low-resistance oil layer in the offshore oilfield development stage, the conventional data are innovatively applied, so that the resistivity curve is replaced to identify the stratum fluid, the defects of the technical means are overcome, and the identification of the ultra-low-resistance oil layer is provided with more accurate basis. The design principle of the method for identifying the offshore ultra-low resistance oil layer by using the gas logging data is that under the condition that an original gas logging curve is influenced by multiple factors, the accuracy is low, and formation fluid is difficult to quantitatively judge, a proper correction method and a proper correction flow are found by analyzing various influencing factors, so that the original gas logging curve is normalized and standardized, the hydrocarbon gas abundance curve obtained after correction can eliminate the influence of errors to the greatest extent, the condition of underground fluid is reflected more accurately, and the effect of identifying the ultra-low resistance oil layer by replacing resistivity is achieved. The method has the advantages that the conventional data are innovatively applied to make up the defects of the prior art means, the method is improved without increasing any data logging and operational cost, and the method plays a great help role in cost reduction and synergy in the offshore oilfield development stage.
It will be understood that the invention has been described in terms of several embodiments, and that various changes and equivalents may be made to these features and embodiments by those skilled in the art without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (2)
1. A method for identifying an offshore ultra-low resistivity reservoir using gas logging data, comprising the steps of:
firstly, single well standardization correction is carried out, wherein the single well standardization correction is based on a gas measurement total quantity curve in a gas logging curve, and the influences of formation pressure, drilling fluid pressure, drilling speed, dissolved gas-oil ratio and drill bit diameter change in the single well range on gas logging data are eliminated through formula calculation, so that a hydrocarbon gas abundance curve of the single well is obtained; the formula adopted in the first step is as follows: ao=tg/Δp/ROP/GOR, where Ao is the hydrocarbon gas abundance curve, TG is the gas measurement total curve, Δp is the pressure differential curve between hydrostatic drilling pressure and formation pressure, ROP is the rate of penetration curve, GOR is the dissolved gas oil ratio curve for each layer;
secondly, interwell normalization correction, namely selecting a large section of water layer section or mudstone section in the oil field range as a standard layer, unifying hydrocarbon gas abundance base values of all wells through multiple operation, eliminating systematic errors, and enabling hydrocarbon gas abundance curves of all wells to carry out fluid identification under unified standards;
thirdly, determining a threshold value of an oil layer of a hydrocarbon gas abundance curve;
and fourthly, screening suspected ultra-low resistance oil layers and checking false images, screening out a small amount of important suspected low resistance oil layers, verifying the oil content of the suspected low resistance oil layers by means of hole filling and sampling, and completing the identification of the offshore ultra-low resistance oil layers.
2. The method for identifying an offshore ultra low resistivity reservoir using gas logging data of claim 1,
the normalization correction between wells in the second step is based on analysis of various influencing factors in the previous step, and systematic errors are caused between wells by partial drilling factors and logging factors in the drilling process, wherein the systematic errors comprise different sensitivity degrees of different logging recording instruments, different initial settings and different logging values recorded under the same condition; in order to eliminate the influence of the factors, on the basis of the hydrocarbon gas abundance curve obtained in the last step, a large-section water layer section in a depth range is selected as a standard layer, hydrocarbon gas abundance base values of all wells are unified through multiple operation, the diameters of drill bits, slurry density, viscosity and instrument system errors are eliminated, the system correction of the hydrocarbon gas abundance curve of each single well is completed, and fluid identification and residual oil saturation calculation are carried out on all wells under the unified standard; for single gas and recycle gas factors which are difficult to correct, when a relative hydrocarbon gas abundance curve is applied, checking in a gas logging abnormal well section through the characteristic combination of the single gas and recycle gas factors in the area;
the third step of hydrocarbon gas abundance curve threshold value determination is to determine a hydrocarbon gas abundance curve threshold value of a known oil layer through data statistics and analysis, wherein the threshold value is the lowest value, and well sections with hydrocarbon gas abundance curve values higher than the threshold value are searched for in other positions in the oil field through the threshold value and serve as preliminary suspected targets;
and the fourth step of screening the suspected ultra-low resistance oil layer and checking the false image is to judge that the suspected target is the suspected ultra-low resistance oil layer or the false image according to the formation mode of the same layer of the oil field and the peripheral similar area, so that a small amount of important suspected low resistance oil layer is screened out, the oil content of the suspected ultra-low resistance oil layer is verified through hole filling and sampling, and the identification of the offshore ultra-low resistance oil layer is completed.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104329079A (en) * | 2014-09-09 | 2015-02-04 | 中国石油大学(北京) | Method and system for recognizing gas logging oil and gas reservoir |
| CN109653739A (en) * | 2018-12-12 | 2019-04-19 | 中法渤海地质服务有限公司 | It is a kind of for correcting the compound logging curve processing method of gas detection logging influence factor |
| CN109667576A (en) * | 2018-12-25 | 2019-04-23 | 西安石油大学 | A kind of high salinity origin cause of formation low-resistivity reservoir Logging Identification Method |
| CN110593855A (en) * | 2019-10-14 | 2019-12-20 | 中石化石油工程技术服务有限公司 | Well logging resistivity correction method and oil layer identification method |
| CN111008451A (en) * | 2019-10-14 | 2020-04-14 | 中国海洋石油集团有限公司 | Logging interpretation method for rapidly identifying hydrocarbon reservoir |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104329079A (en) * | 2014-09-09 | 2015-02-04 | 中国石油大学(北京) | Method and system for recognizing gas logging oil and gas reservoir |
| CN109653739A (en) * | 2018-12-12 | 2019-04-19 | 中法渤海地质服务有限公司 | It is a kind of for correcting the compound logging curve processing method of gas detection logging influence factor |
| CN109667576A (en) * | 2018-12-25 | 2019-04-23 | 西安石油大学 | A kind of high salinity origin cause of formation low-resistivity reservoir Logging Identification Method |
| CN110593855A (en) * | 2019-10-14 | 2019-12-20 | 中石化石油工程技术服务有限公司 | Well logging resistivity correction method and oil layer identification method |
| CN111008451A (en) * | 2019-10-14 | 2020-04-14 | 中国海洋石油集团有限公司 | Logging interpretation method for rapidly identifying hydrocarbon reservoir |
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