Lithologic Reservoirs

The sand bodies of Jishan delta of Shahejie Formation in Huimin Depression are consisted of feldspathic sandstone and lithic sandstone, mainly experienced compaction, cementation, dissolution and metasomatismin the burial diagenetic evolution, and the diagenetic evolution reached the middle diagenetic stage, which results in the mediumporosity and lowpermeability reservoir（current burial depth 1 700～3 500 m）. The dissolution played a significant role in improving reservoir properties in the burial diagenetic evolution. The intergranular pores and intragranular pores, caused by the feldspar dissolution in the depth of 2 400～2 600 m, are constructive for the reservoir properties in increasing the porosity and permeability（the porosity up to 25% and the permeability up to 50 mD）. Obviously, the zone where the dissolution and the secondary pores developed is very important for predicting favorable reservoir.

Improvements of seismic coherence measure and an integrated use of this attribute for studying fracture reservoirs in the Donets Basin, Ukraine

Yuriy Tyapkin， Iana Mendrii

2013, Vol.25(5): 8–12 Abstract ( 567 ) PDF (710 KB) ( 478 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.002

Seismic coherence is a popular attribute intended to image discontinuities caused by variations in structure, stratigraphy, lithology, porosity, and the presence of hydrocarbons. We improve the technology of computing and utilizing this attribute. After analyzing the relation of this attribute to the supposed mathematical model of seismic data, we present a newmethod for estimating coherence. It is based on a more realistic data model that permits arbitrary variations of both signal amplitudes and noise variances between the traces participating in coherence calculation. Moreover, a generalized approach to enhance the horizontal resolving power of any coherence measure is suggested. The newmethods are tested on synthetic data. Moreover, in combination with another seismic attribute, curvature, the new coherence measure is used for studying coalbed-methane-bearing fracture reservoirs in the Donets Basin ofUkraine.

Main controlling factors and models of oil and gas accumulation and distribution in uplift area outside source rock: An example from Fuyu oil layer in Xingbei area, Songliao Basin

FU Guang， XUE Pan， SUN Tongwen， ZHANG Li

2013, Vol.25(5): 13–17 Abstract ( 533 ) PDF (753 KB) ( 516 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.003

Based on the study of reservoir types and distribution law, this paper studied the main controlling factors and models of oil and gas accumulation and distribution of Fuyu oil layer in Xingbei area by comprehensive analysis of oil and gas distribution and accumulation conditions. The result shows that oil and gas of Fuyu oil layer mainly distribute in the north of central anticline zone and in southwest of Xingbei area. The oil and gas accumulation and distribution of Fuyu oil layer in the north of central anticline structure zone is controlled by following two factors:①lateral transporting of fault provides migration pathway for oil and gas accumulation;②the high position of anticline structure in the north is favorable for oil and gas to accumulate. The oil and gas accumulation and distribution of Fuyu oil layer in the southwest of Xingbei area is controlled by following two factors:①lateral transporting of sand bodies provides migration pathway for oil and gas accumulation;②antithetic fault controls oil and gas enrichment. There are two oil and gas accumulation models in Xingbei area: one is that oil and gasmigrate through faults and accumulate in high position of anticline structure,and mainly distribute in the north of central anticline structure zone; the other is that oil and gas migrate through sand bodies and are sealed by antithetic faults, and mainly distribute in the southwest ofXingbei area.

Cl- evolution mechanism of Yanchang stage of Late Triassic in Ordos Basin and its significance

QI Yalin，GUO Zhengquan，CHU Meijuan，CHENG Dangxing，ZHANG Zhongyi

2013, Vol.25(5): 18–23 Abstract ( 451 ) PDF (702 KB) ( 683 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.004

Cl- is the most important anion in the formation water chemical composition of the Upper Triassic Yanchang Formation in Ordos Basin, and it is the most important index to decide the formation water type, total salinity and salinity. Paleosalinity has important influence on oil and gas generation and preservation, the restoration of paleosalinity is important for the reconstruction of paleoenvironment and paleogeography and assessment of petroleum system. This paper analyzed the distribution characteristics of Cl- concentration and total salinity of the reservoir of Yanchang Formation, drew on the latest research achievements of modern lake environment, and studied the Cl- evolution mechanism from the aspects of basin evolution, sedimentary facies, paleoclimate and ancient seawater intermittent injection. The result shows that the intensity of water circulation is the dominant controlling factor for Cl- concentration and total salinity, sedimentary facies and different hydrogeological environment formed by lake basin evolution are important factors for controlling Cl- concentration and total salinity, and paleoclimate and ancient seawater intermittent injection may have certain control effect on Cl- concentration and total salinity. The formation water types and total salinity have important significance for the found, identification and evaluation of reservoir.

Research progress of reservoir microscopic pore structure

WANG Liqun，LI Chao，LI Qizheng，MA Kuiqian，LI Hongying，ZHU Xiaomin

2013, Vol.25(5): 24–30 Abstract ( 463 ) PDF (1112 KB) ( 359 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.005

To establish the fine stratigraphic framework and definite the sedimentary microfacies and depositional model of Lüda 10-1 Oilfield is necessary for field development. Oil group Ⅱ and Ⅲ of the under second member of Dongying Formation are corresponding to twomiddle-term declining hemicycle in Lüda 10-1 Oilfield, sediment source came fromnorthwest provenance, sediments followed twomain branches of watercourses towards the basin, and formed underwater distributary channel, mouth bar and sheet sands deposition within braided river delta front. Sand body thickness of oil group Ⅱ is great, sand body thickness of the small layer is generally greater than 10 m, the sand bodies distribute in the whole region, from northwest to southeast, and along the direction of sediment source, sand bodies extend up to 2 000 m. The sand body thickness of oil group Ⅲ is thinner, sand body thickness of the small layer is generally less than 8 m, and sand bodies extend about 1 000 malong the direction of sediment source.

Study on diagenesis of Chang 8 tight sandstone reservoir in Zhenjing area

XIONG Di， DING Xiaoqi， ZHU Zhiliang， LE Jinpeng

2013, Vol.25(5): 31–36 Abstract ( 474 ) PDF (1160 KB) ( 319 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.006

The sand ofChang 8 reservoir ofUpper Jurassic Yanchang Formation in Zhenjing area belongs to tight and low permeability reservoir. Based on the analysis of cast thin section, cathodeluminescence and scanning electronic microscope, this paper studied the characteristics and types of diagenesis ofChang 8 reservoir. The results showthat the sandstone reservoir in this area mainly experienced compaction, cementation and dissolution, the diagenetic evolution reached the middle diagenetic stage A, and reservoir physical properties were controlled by digenesis. Mechanical compaction and carbonate cementation are the major destructive diagenesis, the chlorite rimon the grain surface plays a constructive role in protecting primary intergranular pores, and the secondary pores created by dissolution of feldspar improve the reservoir properties.

Study on the reservoir properties of the interval of oil shale in Damintun Depression

MA Manxing

2013, Vol.25(5): 37–43 Abstract ( 581 ) PDF (1122 KB) ( 692 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.007

By using the data of thin section, X-ray diffraction, argon ion polishing scanning electron microscope, mercury injection test, specific surface area measurement, geochemical analysis and oil shale retorting, this paper analyzed the lithology characteristics, mineral components, physical properties and oil potential of the oil shale interval in Damintun Depression, and evaluated the reservoir properties. The results show that the interval of oil shale has the typical “sandwich” structure. The up and low layers are oil shale, with mudstone, sandstone, marlstone and basalt in the middle. The oil shale has pelitic texture, laminar structure and bedding fracture. The content of quartz and carbonate is generally high in oil shale, so it is easy to form oil shale reservoir space, such as structural fractures and dissolved pores. Oil shale and mudstone are relatively homogeneous and they are characterized by small pores and low permeability. The specific surface area, pore diameter and total pore volume of oil shale are all bigger than that of mudstone. The hydrocarbon show of the interval of oil shale is common, especially in sandstone and marlstone, and the gas logging abnormal of oil shale is obvious. Oil content of oil shale is in intermediate level by retorting. The potential hydrocarbon generation amount of oil shale is high, reaching the shale oil enrichment standard by Lu Shuangfang. The formation tests on three old wells are successful and S224 well has mined a lot of shale oil, which proves that the interval of oil shale can meet the shale oil storage requirements in Damintun Depression.

Relation between Jurassic paleogeomorphology and hydrocarbon accumulation in Zhenyuan Oilfield, Ordos Basin

MAO Feiyue， HOU Changbing， GOU Xingfu， WU Zemin

2013, Vol.25(5): 44–48 Abstract ( 530 ) PDF (840 KB) ( 522 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.008

Based on drilling and logging data, copying method was used to recover the paleogeomorphology of Jurassic in Zhenyuan Oilfield. By analyzing the relation between reservoir distribution and paleogeomorphology, this paper defined the controlling effect of paleogeomorphology on hydrocarbon accumulation, and established the hydrocarbon accumulation model of Jurassic in Zhenyuan Oilfield. The result shows that there mainly developed 5 types of paleogeomorphology units in Zhenyuan Oilfield, including valley, incised valley, highland, clinoform and mound. The Jurassic reservoir in Zhenyuan Oilfield is controlled by ancient landform, and mainly distributed in the erosion highland periphery of ancient landform and the front as well as the mouth of slopes. Ancient landform is favorable for reservoir formation: incised-valley controls the hydrocarbon migration channel, clinoform affects the types and distribution of reservoir sandstone, and differential compaction between highland controls the relatively high-points in structure. The models of Jurassic hydrocarbon accumulation are mainly slope-mouth, mound and ancient highland in Zhenyuan Oilfield.

Sequence stratigraphic framework and source-reservoir-caprock assemblage of Yanchang Formation in western Nanliang area, Ordos Basin

ZHAO Tianlin1， LUO Jinglan， DENG Yuan， LI Miao， BAI Xuejing， GUO Tao

2013, Vol.25(5): 49–58 Abstract ( 465 ) PDF (1677 KB) ( 471 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.009

In order to study sequence stratigraphic framework and source-reservoir-caprock assemblage of Upper Triassic Yanchang Formation in western Nanliang area, this paper studied the sequence boundary types, the characteristics of sequence stratigraphic framework, and the relationship between long-term base-level cycle and source-reservoir caprock assemblage by the theory and approach of high resolution sequence stratigraphy. The result shows that five third-order sequence boundaries are identified, the Yanchang Formation consist of four long-term and one super-long term base-level cycles. The source-reservoir-caprock assemblage has close relation to the long-term base-level cycle. The sand bodies of delta plain distributary channel and front underwater distributary channel developed in the early middle stage of the uprising periods and middle-late stage of subsiding periods are high quality reservoir, the turbidite sand bodies developed in the middle-late stage of the uprising periods and early-middle stage of subsiding periods are potential reservoir, and the lacustrine shale and carbon mudstone developed in the surrounding of transforming interface of uprising to subsiding of the long-term base-level cycle. The Yanchang Formation developed three types of source-reservoir-caprock assemblage, including upper-sourcing and lower-reservoir type and lower-sourcing and upper reservoir type and self-sourcing and self-reservoir type.

Oil sand reservoir characteristics and diagenesis in Houba area, northwestern Sichuan

YANG Xuefei， WANG Xingzhi， ZHANG Shaonan，ZHANG Bowen， HU Shunqing， LIN Gang

2013, Vol.25(5): 59–64 Abstract ( 528 ) PDF (1089 KB) ( 527 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.010

Oil sand of Middle Jurassic Shaximiao Formation in Houba area in the frontier Longmen Mountain is one of the most typically important unconventional resources. Based on crop and core observation, this paper discussed the reservoir characteristics of oil sand and its diagenesis in Houba area. The result shows that the reservoir sandstones are mainly medium-coarse grained sublitharenite and litharenite, the main pore types are residual intergranular pores and intergranular dissolved pores, and fractures are common. The sandstone reservoir has the characteristics of medium high porosity and medium permeability. Diagenesis includes compaction, cementation and dissolution, and dissolution and chlorite cementation are constructive for the preservation of pores. Dissolution generally developed within grain and boundary of unstable grain, and formed great number of secondary dissolved pores. Chlorite cementation can improve the rock compaction resistance. Compaction, carbonate cementation and quartz overgrowth cause damages to the reservoir pores.

Palaeogeomorphology reconstruction and sand body distribution of Chang 7 reservoir in Zhenbei area, Ordos Basin

CUI Longtao， FENG Dong， QIN Yanqun， PENG Yidong

2013, Vol.25(5): 65–69 Abstract ( 463 ) PDF (964 KB) ( 854 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.011

Chang7 member of Yanchang Formation in Zhenbei area is one of the maintargets ofoil and gas exploration. The type and distribution of sand body are controlled by palaeogeomorphology. The recontructed palaeogeomorphology based on precise isochronous stratigraphic framework can provide basis for analyzing the genesis type and distribution of the sand body. Based on core, logging and seismic data, this paper established fine stratigraphic framwork under the guidance of high resolution sequence stratigraphy, and divided Chang7 reservoir into one middle-term base-level cycle and five short-term base-level cycles. An optimized back stripping method was used to restore the deposited terrain, and the paleogeomorphology map of the study area was drawn by short-term base level unit. The result shows that there mainly developed slope break in Zhenbei area, Chang73 is the maximum transgression, and turbidite fans appear in the deep lake in the northeastern part of the study area. From Chang 73 to Chang 71 stage, the base level decreases, the mouth bar and the slope break zone gradually advance to the lake, the angle of the break zone begins to decrease,and fluxoturbidite forms consequently; from late Chang 71 stage,the base level begins to rise, the slope break and the sandbody gradually retreat to the shore. Base level cycle change leads to geomorphic change, the origin and distribution of the sand bodies changes regularly, and it has an important significance in searching for oil and gas.

Quantitative prediction of porosity of tight sandstone reservoir: A case study from Chang 8 oil reservoir set in Jiyuan area, Ordos Basin

LIU Chang， ZHANG Qin， PANG Guoyin， WANG Qi， LIAO Peng， MA Xiaofeng

2013, Vol.25(5): 70–75 Abstract ( 536 ) PDF (885 KB) ( 504 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.012

The Chang 8 oil reservoir set in Jiyuan area is typical tight sandstone reservoir with lowporosity and permeability. Due to the complex pore structure and strong reservoir heterogeneity, it is circumscribed to calculate the porosity by the traditional way. Combined with the geological characteristics ofChang 8 oil reservoir set in Jiyuan area, generalized regression neural network was applied to predict the porosity of tight sandstone reservoir. The result shows that the porosity predicted by the generalized regression neural network method is consistent with the porosity by well core analysis. Therefore, this method is of very good application value on porosity prediction of tight sandstone reservoir in the non-cored area.

Application of time-frequency analysis technology to the gas detection in Sulige area

ZHANG Menggang， HONG Zhong， DOU Yutan， CUI Xiaojie

2013, Vol.25(5): 76–80 Abstract ( 470 ) PDF (1093 KB) ( 605 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.013

When seismic waves get through gas reservoir, the energy of high frequency will be attenuated. So we can predict oil reservoir by energy of high frequency. Firstly, through the comparison of the four spectrum decomposition algorithm: short-time Fourier transform, wavelet transform, generalized S transform and matching pursuit decomposition, we proved that matching pursuit decomposition method has higher time-frequency resolution. Secondly, we verified that the energy of high frequency will be attenuated when seismic waves get through gas reservoir. Finally, the matching pursuit decomposition method was applied to spectrumdecomposition of 3D seismic prospect in Sulige area. Meanwhile, high frequency attenuation was used to predict the gas-bearing properties, and the result is in accordance with actual drilling data, which proves the practicability of this method.

Application of “two step inversion” technology to the prediction of tight sandstone gas reservoir: A case study from Su X block in Sulige Gas Field

LI Xinyu， ZENG Qingcai， BAO Shihai， HUANG Jiaqiang

2013, Vol.25(5): 81–85 Abstract ( 485 ) PDF (1144 KB) ( 523 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.014

The tight sandstone reservoir is developed in the eighth member of Shihezi Formation in Su Xblock of Sulige Gas Field. The reservoir has the characteristics of lowporosity, lowpermeability, lowabundance and strong heterogeneity. It has complex overlapping pattern of sand bodies, complex gas and water relationship and non-uniformair-water interface between gas and water-bearing sands. Howto apply seismic technology to predict favorable gas-bearing areas becomes one of the main problems in this block. Based on comprehensive analysis of reservoir geologic features and geophysical characteristics, this paper explored the “two step inversion” technology for predicting favorable gas-bearing areas. Firstly using frequency division inversion method to predict sand body enrichment area, and then using wave impedance inversion to predict gas-bearing properties of the sand, and finally combining the two methods to predict favorable gasbearing areas of the eighth member of Shihezi Formation in Su X block. The practical application indicates that this method reduces the multiple solutions and improves the accuracy of prediction, and can be used to predict favorable gas bearing area effectively.

Application of self-adaptive BP neural network to the prediction of shear wave velocity

WANG Xiaoguang

2013, Vol.25(5): 86–88 Abstract ( 476 ) PDF (747 KB) ( 532 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.015

Accurate shear wave velocity is the necessary information for prestack inversion and prestack attribute analysis, but it is always deficient in actual production. The prediction methods are numerous and complicated and the accuracy is difficult to ensure. By selecting the parameters such as relative natural gamma-ray value, acoustic slowness, density and resistivity, this paper used the method of self-adaptive BP neural network to establish the prediction model of shear wave velocity. The actual data in Liaohe Oilfield showthe high precision of the prediction value, and the results can meet production requirements.

Seismic identification and prediction method of volcanic lava and its application

PI Xiong， JIE Li

2013, Vol.25(5): 89–93 Abstract ( 436 ) PDF (1123 KB) ( 704 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.016

Volcanic lava is widely distributed in Yingcheng Formation of Yingtai fault depression in southern Songliao Basin. It is one of the most important hydrocarbon reservoirs of volcanic reservoirs. The reservoir is characterized by large thickness, excellent reservoir properties and high productivity, and has favorable prospect. Volcanic lava has complicated lithologies, variable seismic reflection characteristics and strong heterogeneity, so it is difficult to define the volcanic lava boundary and identify volcanic apparatus. Besides, deep reservoir burial, lowquality of seismic data, low-angle of gathers and superposed wave impedance enhance the difficulty of the reservoir prediction. This paper applied several techniques to identify the boundary and inner of volcanic lava of Yingcheng Formation, and defined its distribution. According to the log response and gas reservoir characteristics, we used pre-stack simultaneous inversion technology based on log reconstruction, which improves the inversion accuracy and reliability of prediction of volcanic lava reservoir. This method provides newthought and method for the identification and prediction of this kind of complicated reservoirs.

Study on P and S wave separation method in cross-well seismic and its application

FENG Yuping， DIAO Rui， XU Weixiu， YANG Jing， SONG Jianguo

2013, Vol.25(5): 94–99 Abstract ( 481 ) PDF (1346 KB) ( 592 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.017

Three-component seismic acquisition technology used in VSP and cross-well seismic can record wealthy seismic wave field. The P and S wave couple together, which becomes the difficulty and emphasis of data processing. Through analyzing borehole seismic acquisition system, combined with polarity relation of P and S wave in different components, we can associate polarity of P and S wave with apparent velocity and direction of seismic wave reaching the geophone array. According to this relation, we obtained the distribution relation of P and S wave in τ- p domain based on the linear Radon transform （LRT）. Considering the convergence of LRT, we designed a polarization filteringmethod using the high-resolution Radon transform, and then accomplished the separation of P and S wave. The processing of simulated data of theoretical model and practical cross-well model separated P and S wave field successfully, which is useful for independent imaging of P and Swave.

Forecasting method of development index based on liquid/oil ratio in extra-high water cut stage

GUAN Heng

2013, Vol.25(5): 100–103 Abstract ( 424 ) PDF (672 KB) ( 585 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.018

Aiming at the development characteristics in extra-high water cut stage, based on the research of several forecastingmethods of development index, according to the change characteristics of liquid/oil ratio in extra-high water cut stage, this paper established a forecasting model based on liquid-oil ratio, and deducted the relationship between liquid/oil ratio and water cut and the relationship between liquid/oil ratio and decline rate. The result shows that with the accumulated liquid production rising, the ascending velocity of water cut is slowdown, and when the growth rate of liquid production and liquid/oil ratio is equal, the oil production is stable. This forecasting model proves high prediction accuracy, and it is practical for oilfield development index in extra-high water cut stage.

Research on physical simulation and numerical simulation of horizontal well chemical flooding

YU Tianzhong

2013, Vol.25(5): 104–108 Abstract ( 505 ) PDF (970 KB) ( 520 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.019

Based on actual data from J16 block in Liaohe Oilfield, this paper established physical models of 30 cm× 30 cm×1.5 cmareal heterogeneity horizontal well and 30 cm×15 cm×10 cmvertical heterogeneity horizontal well. We carried out physical simulation and numerical simulation of horizontal well chemical flooding, and analyzed the oil displacement mechanism and production performance of horizontal well chemical flooding. It is concluded that the direction of horizontal well should be paralleled with the river channel trend, horizontal injection well should be deployed in the high permeability zone and horizontal production well should be deployed in the low permeability zone in plane, horizontal injection well should be deployed in lower location and horizontal production well should be deployed in higher location in vertical, and polymer and surfactant combination flooding is recommended.

A new method for water cut rising forecasting of vertical wells in bottom water reservoir

WANG Tao

2013, Vol.25(5): 109–112 Abstract ( 524 ) PDF (738 KB) ( 594 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.020

Bottom water coning is an important factor affecting reservoir development effect. Based on the theoretical investigation, numerical model of bottomwater reservoir is established. The accumulate oil production, water production and fluid production rate fromthe numerical simulation result were applied to calculate Yu Qitai water drive characteristic curve, and parameter b which can reflect water cut change in vertical wells was obtained. We used the response surface experimental design analysis method to study the effect of different factors on b value, and established the relation formula between the main influencing factor and b value. According toYu Qitai curve b chart, the regression curve and chart method for forecasting water cut change rule of vertical wells in bottom water reservoir was obtained. This chart method was used in H12 well in an oilfield, the results prove the veracity. So this method is effective for forecasting water cut change rule of vertical wells in bottom water reservoir.

Study on the potential tapping and adjusting of ultra-low permeability reservoir in Wei 42 block

DONG Fengling，ZHOU Huadong，LI Zhixuan，CHEN Yingying，BI Yushuai，WANG Lei

2013, Vol.25(5): 113–116 Abstract ( 446 ) PDF (987 KB) ( 442 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.021

The reservoir in Wei 42 block of PuchengOilfield was characterized by deep burial, poor physical properties, unclear sedimentary environment and sand body connectivity, strong heterogeneity, difficult water injection, imperfect well spacing and lowefficient development. Based on fine reservoir description and performance analysis of production, this paper studied the types and distribution of remaining oil. The remaining oil types were classified into interlayer interference type, structural high part type, imperfect injection-production type and lenticular sand body type. Aimed at the geological characteristics of reservoir and different types of remaining oil, manymeasures were carried out, such as enlargement adjustment, regrouping of layers, and adjustment of injection-production well spacing and well spacing density. The application result shows that well pattern optimization and well pattern thickening for different types of remaining oil distribution improved the development effect.

Preliminary study on the theory of water phase transitions controlling the formation of oil and gas

HU Baoqun， SUN Zhanxue， LI Mangen， BAI Lihong

2013, Vol.25(5): 117–122 Abstract ( 378 ) PDF (791 KB) ( 452 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.022

Both the organic genesis theory and inorganic genesis theory on the formation of oil and gas have their own evidences, but any one always has some phenomena not to be satisfactorily explained. In the study of the genesis of oil and gas, the theory of water phase transition controlling hydrothermal mineralization may give a better explanation, or at least provide some new ideas. According to the theory of water phase transitions controlling the formation of oil and gas, the generation and migration of oil and gas are always mixed with water together, even the hydrocarbon is as a special hydrothermal mineral. Under a closed system in the crust, according to the upper crust hydrothermal geothermal lines, the fluid mixed hydrocarbon with water is the liquid phase. But when pressure reduction caused by the fault or fold, the fluid system will take place the separation of water and hydrocarbon, and result in the formation of oil and gas reservoirs. Bases the theory, this paper analyzed the phenomena related with hydrothermal mineralization in the formation of oil and gas. With the laws of water phase transitions in the lithosphere, this paper also explained briefly the geneses oneness of the formation of oil and gas, hydrothermal metal ore-deposit, the low velocity-high conductivity layer, the earth degassing and the earthquakes.

Research progress of reservoir microscopic pore structure

HAO Lewei， WANG Qi， TANG Jun

2013, Vol.25(5): 123–128 Abstract ( 779 ) PDF (863 KB) ( 1076 )

doi: https://doi.org/10.3969/j.issn.1673-8926.2013.05.023

Reservoir microscopic pore structure directly affects the reservoir storage and permeability, so the research on reservoir microscopic pore structure characteristics can help to carry out reasonable classification evaluation of reservoir, and find out reservoir distribution law, improve the productivity and recovery ratio of oil and gas. Based on a large number of relevant literatures, this paper summarized and expounded the origin, test methods, theory research progress and comprehensive evaluation of reservoir microscopic pore structure, analyzed the main existing problems in the research of domestic reservoir microscopic pore structure, and pointed out that the research of the domestic micro structure is mainly based on traditional methods, having the problem of insufficient combination with domestic actual geological condition and lack of quantitative research.