Abstracts

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Abstract：In order to know the contributing factor and distribution of effective reservoirs，the type of diagenesis and diagenetic evolution were studied via core analysis，thin section analysis，and core conventional analysis.The result showed：the main rock type are arcose and lithic arkose，and the textural maturity and compositional maturity are moderate.Dissolution pores are the main pores，as well as a few primary pores and fractures.The buried depth of the reservoirs in E s2 and E s3 is very high，making the porosity and permeability low to moderate.The diagenetic stage of the reservoirs belongs to stage B of the early diagenesis，and stage A of the middle diagenesis.Diagenetic analysis indicates that secondary pores mainly exist vertically in a depth range of 2 400～2 800 m due to the process of the maturation of source rocks.This study will be helpful to guide the oil and gas exploration and development.

Raoyang sag；Wuqiang oilfield；the second member of Shahejie formation；the third member of Shahejie formation；diagensis

Abstract：For the effective searching and predicting development areas of"sweet spot"reservoir in the tight sandstone，using the cast thin section identification，scanning electron microscopy observation，combining the test data of physical properties with fluid inclusion homogenization temperature for comprehensive analysis，T3x4、T3x6is a typical density low permeability gas reservoir within Xujiahe formation in low-steep structure of Shunan area.Diagenetic evolution of the reservoir sand body can be divided into three evolution paths：diagenetic sequences mainly with the compaction and secondary quartz overgrowth，diagenetic sequences mainly with chlorite rim and predominantly early calcite cementation；furthermore analysis of the densification mechanism of sandbody.The results show that sedimentation is the congenital factor to physical property of sand reservoir.Compaction is the key factor for reservoir densification.Secondary quartz overgrowth could destroy the quality of reservoir.Lower dissolution degree is another key factor for reservoir densification；and the time of reservoir densification is before the hydrocarbons filling.The homogenization temperature of saline fluid inclusions distributed between 82.5～125.1℃，concentrated distribution between 100.0℃～120.0℃，thus the prediction of densification depth is between 1 725～2 864 m，secondary quartz overgrowth，thus the densification process oc-curred during Yanshan tectonic activity.When the buried depth continued to increase，the hydrocarbons began charging，thereby the continuing of water-rock reaction were suppressed.The results of this studying provide the reliable geological data for reservoir predicting of"sweet spot"in Xujiahe formation.

Key words：densification mechanism；densification time；diagenetic evolutionary path；Xujiahe formation；southern Sichuan basin

Abstract：The lower 2nd member sand beds I and II of Xujiahe formation in Yuanba area have good gas bearing potential according to recent exploration achievements.The reservoir characteristics are revealed in this paper through a serious of aggregate analysis including cores observation，rock and mineral composition analysis，mercury injection experiments，thin sections，cast thin sections.Among the four lithologys that have been revealed，Lithic sandstone and feldspathic lithic sandstone are deposited in delta front sub water distributary channel environment，while quartz sandstone and lithic quartz sandstone are deposited in shore-shallow lacustrine environment.The reservoirs have low porosity，low permeability and very complicated pore and throat structures，and the mercury injection experiments illustrate that the quartz sandstone has the better pore and throat structures than the other lithology.The reservoir pores are dominated by secondary solution pores，cracks are dominated by horizontal and low angle fractures.Reservoir characteristics are controlled by sedimentary and diagenesis.Different microfacies control the component and texture maturity，and consequently affect the development of primary and secondary pores.The compaction is the main reason for the destruction of primary porosity.Cementation were mainly formed in the middle late diagenesis stage and thus destructed the primary porosity，but some clay cementation have the effects of keeping the pore space，dissolution is the main factors of forming secondary pores，improving the porosity，and the development of high quality reservoirs.The research provides supports to the evaluation and exploit of the gas reservoir.

Key words：Yuanba area；Xujiahe formation；reservoir characteristics；control factous

Abstract：This paper studied the distribution features of shale，types of kerogen，abundance，maturity，reservoir characteristics and accumulation of shale-gas of the lower Cambrian organic-rich marine mud shale in the Xiuwu basin through field geological survey，core observation，test analysis and field gas content testing.The lower Cambrian black shale in the Xiuwu basin was characterized by great thickness，wide distribution，high organic carbon content and high maturity.In addition，the shale has high brittle mineral content(over 40%)and plenty of micro-porosity and micro-fractures，which shows a good prospects for of shale gas exploration.The amount of shale-gas resources in the lower Cambrian was calculated to be 2 922.98×108m3by isothermal adsorption simulating experiment and gas content measurement with the volumetric method.The great thickness(over 100 meters)，high organic content

(more than 6%)，moderate thermal evolution(vitrinite reflectance betweens 2%～3%)of Wangyinpu group shows that eastern of Xiushui-Wuning syncline is the most realistic and favorable target for shale gas exploration.Moreover，the moderate burial depth(range from 1 000 to 3 000 meters)，simple structure and fewer faults is conducive to the preservation of shale gas.

Key words：Xiuwu basin；lower Cambrian；shale gas；accumulation condition；favorable area of shale gas

Abstract：In this article，the architecture and sequence character of transient lobe developed in the Pleistocene will be construed by the three-dimensional seismic data set from the Niger delta deepwater area，based on which the sedimentary process and the control of morphology is analyzed.The developed model is also constructed to permits the predictive models for application to deeper reservoir systems，which confirmed effecting of topography and sediment supply to the development and evolution of transient lobe.The transient lobe scale and distribution restricted 1by the local low lands，which show obvious fast filling progress，whose reservoir distribution is better than the linear channel，and has good reservoir property.its development progress can be divided into five stage controlling by the local low lands，gravity flow density and sea level changing，which includes the original topography，initial filling，late filling，overflow，bypass and erosion.and in which there is different reservoir characteristics and distribution.

key words：Niger delta basin；deepwater fan；transient lobe；sedimentary characteristics；development model

Abstract：In order to further understand of sequence stratigraphy and depositional filling type for Shahezi formation in Lishu depression in Songliao basin，the sequence stratigraphy and sedimentary facies were identified by comprehensive utilization of well drilling and seismic data of Shahezi formation in Xidingjia area.The research results show that the Shahezi formation was divided into two third-order sequences SQ1 and SQ2 by the identification of SB1，SB2 and SB3 sequence boundaries；the third-order sequence was divided into lowstand system tract，transgressive system tract and highstand system tract.The lowstand system tract accumulation mode is mainly progradational，while the transgressive system tract is retrograding and highstand system tract is characterized by prograde and accretion.Sedimentary types are mainly fan delta，braided river delta and lake，among them fan delta and braided river delta are the most important facies types in the area.The fan delta developed on downthrown side of steep slope，obviously controlled by the strong subsidence；the braided river delta mainly developed in gentle slope belt characterized by long axis provenance，and sequence development，tectonic evolution and depositional filling response were synchronous.The theoretical foundation will be provided in order to looking for subtle reservoirs of deep depression in southeast Songliao basin and determine the favorable exploration direction.

Key words：sequence stratigraphy；sequence boundary；sedimentary facies；characteristics of filling response；Songliao basin；Xidingjia area；Shahezi formation

Abstract：In order to reconstruct the depositional setting and study the enrichment mechanism of organic matter of the lower Silurian black shale series，southeast of Chongqing，samples were systematically collected from Lujiao outcrop section.Many experimental tests such as Rock-Eval，X-ray diffraction，trace element，and BET and pore size analysis were conducted.Results show that the black shale series is in the B stage of middle diagenesis and palaeosalinity are 11.1‰～35.4‰with an average of 21.4‰，seawater belong to polyhaline as a whole.w(V)/w(Cr)values are 1.62～3.72，w(V)/w(V+Ni)values are around 0.80，and there is a good positive correlation between the enrichment of Cu，Ni，V and the content of total organic carbon(TOC).These evidences indicate that the depositional setting is a less strongly stratified anoxic water column that transferred from anoxic to dysoxic and then to suboxic environment with the decrease in depth.Upper welling improved palaeoproductivity，then it was weakened during the global palaeoclimate warmer in Silurian，thereupon reducing the palaeoproductivity. High palaeproductivity is the primary condition for the enrichment of organic matter，while high palaeosalinity and anoxic environment is an ideal environment to save organic matter.Moreover，the surface area and the total pore volume positively correlated well with the TOC，indicating that the depositional setting influenced the reservoir physical properties of rocks and consequently affected the occurrence space of shale gas.

Key words：depositional setting；enrichment of organic matter；black shale series；lower Silurian；Lujiao section；southeast of Chongqing

Abstract：Based on representative samples of north area in Hegang coal field that using low temperature nitrogen adsorption method to study the relationship between fractal dimension and pores system and gas adsorption capacity of tectonic coal in different deformation grade.Results show that low temperature nitrogen adsorption and desorption curve display different shape，because of the pores system of cataclastic coal and granulated coal were changed by tectonic.The fractal dimension could characterize pores composition and adsorption capacity of cataclastic coal and granulated coal when relative press between 0.5～1.0.The deformation grade and content of micropores and surface to volume ratio and pores face rugosity increasing，but pore diameter decreasing，with the increasing of fractal dimension.Therefore，the higher fractal dimension indicates that the coal has a higher gas adsorption capacity.The fractal dimension could characterize pores composition and adsorption capacity.

Key words：fractal dimension；pores composition；adsorption capacity；tectonic coal；Hegang coal field；low temperature nitrogen adsorption method

Abstract：According to the statistics of casting thin slice data and inclusion-homogenization temperature data of minerals，the study of reservoir beds characteristics and porosity evolution of the sandstones within the lower Jurassic coal-measure strata in the eastern Kuqa depression，Tarim basin，northwest China，show that the rock composition in this region is mostly lithic sandstone，the decreasing content of compacted pores of present reservoir beds could reach 25%～38%，and the carbonate cements were formed later than the quartz overgrowth edge.The development of favorable reservoir beds are comprehensively controlled by sedimentation，diagenesis and tectonism：The effect on physical property of reservoir bed is more from compaction than from cementation；coarser sandstone possesses stronger compaction resistance and is more vulnerable to dissolution；better developed fractures result in stronger dissolution ability of sandstone.Therefore，the relatively coarse sandstones that occur in braided channel facies and the strongly dissolved strata with well developed fractures are predicted to be the favorable reservoir beds in the study area.The research of favorable reservoir beds can provide some references for the gas forecast and development.

Key words：coal-measure bed；favorable reservoir bed；acidic aqueous medium；lower Jurassic；Kuqa depression

Abstract：Jin 99 block of Dujiatai reservoir，which is heavy oil reservoir in the mid-to-late stage of waterflood development，in Huanxiling oilfield could be regarded as braided-river delta front facie with complex structure and fault system as well as good reservoir properties in spite of the strong heterogeneity. On the base of core observation and combined with drilling，logging，well logging，rock analysis，oil testing and production dynamic test data，this paper makes clear the types of sedimentary microfacies and spatial distribution of the sand body and the relationship between sedimentary microfacies and oilbearing properties.The results indicate that this area is a complete trangressive system deposition inclu-ding 6 kinds of sedimentary microfacies，which are underwater distributary channel subject，underwater distributary channel side edge，channel mouth bar，subsea interdistributary bay，sand sheet and lacustrine mud.The types of sedimentary microfacies are considered to have significant control on the oilbearing of the reservoir.Compared with sand sheet and underwater distributary channel side edge who have inferior oil-bearing property，underwater distributary channel subject and channel mouth bar have better oil potential and contribute to the accumulation of oil and gas.The research results point out the future exploration direction to favorable reservoir sedimentary sand body and provide guidance for the subsequent waterflood development in the oilfield.

Key words：braided-river delta front；sedimentary microfacies；oil-bearing of reservoir；Dujiatai reservoir；Huanxiling oilfield

Abstract：In order to solve the problem of high HPHT fluid loss of synthetic-based drilling fluids，a lipophilic silicified amide derivatives as synthetic based drilling fluids filtrate reducer was prepared on the basis of Activated ester method.The chemical structure and thermal stability were characterized through a combined use of FT-IR and TG-DSC，et al.The performance on fluid loss control of silicified amide derivative FRA-1 was evaluated via HTHP filtration tests，and then compared with several commonly used filtrate reducers.The results show that FRA-1 exhibits a better stability.FRA-1 performances as a synthetic-based drilling fluid additives are much better than the additives for comparison in synthetic-based drilling fluids.It has less impact on the drilling fluid rheology，wherefore it can replace asphalt products.

Key words：filtrate reducer；synthetic-based drilling；high temperature resistance；silicone；humic acid amide

Abstract：Due to the concentration gradient，shale gas in multi-stage fractured reservoirs can simultaneously diffuse from matrix into natural fractures and artificial fractures.On the basis of triple-porosity model，a productivity model of multi-fractured horizontal wells in shale gas reservoir has been established with consideration of desorption，diffusion，seepage.Laplace transform is used to solve this model and obtain the solution in Laplace space.The dimensionless pressure and dimensionless pressure derivative type curves are plotted with Stehfest numerical inversion algorithm.Shale gas flow stages are divided into five regimes：Early linear flow，pseudo-steady state inter-porosity flow，the diffusion from matrix into natural fractures，the diffusion from matrix into artificial fractures and boundary-dominated flow.There are great distinctions of pressure response between pseudo-steady state diffusion and un-steady diffusion under different value of pore volume ratio.The diffusion parameter represents diffusive capacity，the larger the value of diffusion coefficient，the sooner gas diffusion occurs.Langmuir parameters reflect the adsorptive and storative ability，the larger the value of parameters，the stronger the ability of adsorption.The macro fracturing stages have certain impact on shape factor of matrix，the more the fracturing stages，the greater the inter-porosity coefficient，and the sooner the inter-porosity from micro-fractures into artificial fractures occurs.Finally，compared with the real production data，this model is reasonable.These results have great significance for recognizing the principle of production decline，predicting the shale gas production and optimizing the fracturing parameters.

Key words：shale gas；fractured horizontal well；productivity model；desorption；dual-diffusion；type curve

Abstract：Since previous plastic radius prediction model for horizontal wells have ignored the HTHP effect under thermal recovery conditions.A new model to calculate plastic radius near around the wellbore due to thermal recovery wells was proposed in this paper，based on different rock failure criterions. It was proved that with the increase of plastic yield function value at the surface of wellbore，the extent of the wellbore damage increased，and more serious sanding trend followed；Null point of plastic yield function was defined as the outer boundary of the plastic yielding zone，term plastic yielding radius，which is the measurement of sanding zone.Yielding radius increased with the temperature elevation.It has been seen from the analyses of numerical example that order of in situ stress，circumference angle，azimuth angle and injecting pressure are the main factors of plastic yielding radius.More specifically，whenσv＞σH，vertical plastic radius become larger than that of horizontal directions while it is just on the opposite whenσv＜σH.Plastic yielding radius become largest while the maximum horizontal in situ stress is paralleled to wellbore axis，while comes to its contrary while the maximum horizontal in situ stress and wellbore axis are orthogonal with each other.The research result may have some guiding significance on sanding prediction for thermal horizontal wells.

Key words：plastic yielding radius；sanding prediction；thermal recovery；horizontal well；crustal stress around wellbore；sanding radius

Abstract：In order to study the seismic performance of single-span double-layer steel frame，the slenderness ratio，axial compression ratio and the loading position for the parameters，18 groups of single-span double-layer steel frame system was designed.Based on a simplified mechanical model and constitutive relations of material，using ABAQUS software to establish the corresponding finite element model，static analysis of frame structure under monotonic horizontal load was carried out.Through the simulation analysis and test results of the single-span double-layer steel frame，both are in good agreement，the rationality the finite element model is established is verified in this paper.The nonlinear hysteretic analysis of 18 groups of single-span double-layer steel framework is performed，on the basis the author extracted and compared the load-displacement hysteretic curves，the envelope and skeleton curves.Based on the energy equivalent method，ductility factor of structure is calculated，and the plastic hinges of structure system appeared successively and distribution regularity was investigated.Design recommendations of steel frame in the long-span，heavy load and outer-jacketing adding-story engineering are given.The results show that the single-span double-layer steel frame structure has plump hysteretic curve，plastic performance，dissipation energy and ductility are good，and plastic hinge mechanism of strong column and weak beam is formed.These can provide technical support for new engineering and renovation of existing buildings.

Key words：outer-jacketing adding-story structure；steel frame；hysteretic behavior；plastic hinge；design suggestions

Abstract：A class of nonlinear parameters of three order boundary value problem，by using the fixed point index theorem and Green function estimation，we prove the existence of positive solutions of the problem.

Key words：third-order boundary value problem；existence；positive solutions

Diagenesis analysis of reservoirs in E s2 and E s3 in Wuqiang area of Raoyang sag

JIANG Chao1，DENG Aiju2，LI Fengqun2，ZHANG Xinjian3，LI Yun'e2
(1.Geosciences Research Institute，Shengli Oilfield Company，SINOPEC，Dongying，Shandong 257015，China；2.Oil Recovery Plant No.3，Huabei Oilfield，PetroChina，Hejian，Hebei 062450，China；3.Western New Prospect Research Institute，Shengli Oilfield Company，SINOPEC，Dongying，Shandong 257000，China)

Densification mechanism analysis of sandstone densification within Xujiahe formation in low-steep structure in southern Sichuan basin

GU Na1，2，TIAN Jingchun1，2，ZHANG Xiang1，2，LIANG Yuchen2，SU Bingrui2
(1.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation，Chengdu University of Technology，Chengdu，Sichuan 610059，China；2.School of Sedimentary Geology，Chengdu University of Technology，Chengdu，Sichuan 610059，China)

Reservoir characteristics and main controlling factors of high quality reservoir in the lower 2th member of Xujiahe formation in Yuanba area

JIA Shuang，LI Hongtao，XIAO Kaihua
(Petroleum Exploration and Production Research Institute，SINOPEC，Beijing 100083，China)

Shale gas accumulation conditions and favorable areas of the lower Cambrian in Xiuwu basin

PANG Fei1，BAO Shujing1，REN Shoumai1，LI Shangru2，TONG Chuanchuan1，ZENG Li2
(1.Oil and Gas Survey Center，China Geological Survey Bureau，Beijing 100029，China；2.Research Institute of Shale Gas Development and Survey in Jiangxi，Nanchang，Jiangxi 330002，China)

Characteristic and development model of transient lobe in Niger delta basin

HU Xiaolin，YU Shui，LIU Xinying
(CNOOC Research Institute，Beijing 100027，China)

Sequence stratigraphy and depositional filling response in the southeastern margin of Songliao basin：Taking the Lishu fault depression Shahezi stratum formation in the northwest as an example

WU Jiyue1，LU Haijiao2，LI Fuping3，ZHAO Hongge2，LI Wenhou2，SHAN Jingfu4
(1.School of Geosciences and Engineering College，Xi'an Petroleum University，Xi'an，Shanxi 710065，China；2.State Key Laboratory of Continental Dynamics，Department of Geology，Northwest University，Xi'an，Shanxi 710069，China；3.Research Center of Sulige Gas Field，Changqing Oilfield Company，PetroChina，Xi'an，Shanxi 710018，China；4.Key Laboratory of Exploration Technologies for Oil and Gas Resources，MOE，Yangtze University，Wuhan，Hubei 430100，China)

Depositional setting and enrichment mechanism of organic matter of the lower Silurian black shale series in the southeast of Chongqing：A case study from Lujiao outcrop section

SUN Mengdi1，2，YU Bingsong1，2，XIA Wei1，2，QI Qingshan1，2，YE Ruochen1，2
(1.School of Geosciences and Resources，China University of Geosciences，Beijing 100083，China；2. State Key Laboratory of Geological Processes and Mineral Resources，China University of Geosciences，Beijing 100083，China)

Fractal characteristics of tectonic coal from Hegang coal field

WANG Youzhi，WANG Shihui
(Exploration and Development Research Institute of Daqing Oilfield Company Ltd.，Daqing，Heilongjiang 163712，China)

Reservoir bed characteristics of tight sandstones within coal measure strata of the lower Jurassic in the eastern Kuqa depression，Tarim basin，China

QIN Hong1，DAI Qiwen2，3，YUAN Wenfang1，LIU Luofu2，3，CAO Shaofang1，SU Tianxi2，3，ZHANG Bo1，JIANG Zhenxue2，4
(1.Research Institute of Petroleum Exploration and Development，Tarim Oilfield Company，PetroChina，Korla，Xinjiang 841000，China；2.State Key Laboratory of Petroleum Resources and Prospecting，China University of Petroleum，Beijing 102249，China；3.Basin and Reservoir Research Center，China University of Petroleum，Beijing 102249，China；4.Research Institute of Unconventional Natural Gas，China University of Petroleum，Beijing 102249，China)

Relationship between sedimentary microfacies and oil-bearing characteristic of braided-river delta front：In the case of Dujiatai oil reservoir in Jin99 block of Huanxiling oilfield

ZHANG Ruixue1，YANG Shaochun1，ZHANG Ruixiang2，SONG Fan1
(1.School of Geosciences，China University of Petroleum，Qingdao，Shandong 266580，China；2. Shengli College，China University of Petroleum，Dongying，Shandong 257000，China)

Preparation and evaluation of a novel synthetic based drilling fluids filtrate reducer

HAN Zixuan1，2，JIANG Guancheng1，2，LI Qingyang1，2，YAO Rugang1，2
(1.MOE Key Laboratory of Petroleum Engineering，China University of Petroleum，Beijing 102249，China；2.State Key Laboratory of Petroleum Resources and Prospecting，Beijing 102249，China)

Productivity model for multi-stage fractured horizontal well for shale gas reservoirs taking diffusion into consideration

TIAN Leng1，XIAO Cong1，LIU Mingjin2，GU Daihong1
(1.Petroleum Engineering College，China University of Petroleum(Beijing)，Beijing 102249，China；2.School of Geosciences and Technology，Southwest University of Petroleum，Chengdu，Sichuan 610500，China)

Prediction method and its application of formation plastic damage radius for thermal recovery wells

LI Yanlong1，DONG Changyin1，LI Huaiwen2，SHAO Lifei2，CHEN Xin'an1
(1.School of Petroleum Engineering，China University of Petroleum，Qingdao，Shandong 266580，China；2.Petroleum Engineering Research Institute，Dagang Oilfield Branch，CNPC，Tianjin 300280，China)

Hysteretic behavior analysis and design of the single-span and double layer steel frame based on the outerjacketing storey-adding

JI Jing1，2，LI Bing1，3，DAI Jianguo2，ZHANG Wenfu1，3，LIU Yingchun1，3，XING Fei1，3
(1.Heilongjiang Key Laboratory of Disaster Prevention，Mitigation and Protection Engineering，Daqing，Heilongjiang 163318，China；2.Department of Civil and Structural Engineering，Hong Kong Polytechnic University，Harg Hom，Kowloon Hong Kong，China；3.College of Civil Engineering，Northeast Petroleum University，Daqing，Heilongjiang 163318，China)

Existence of positive solutions for a class of third-order three-point boundary value problem

KONG Lingbin，JIN Qiande
(Institute of Mathematical and Statistics，Northeast Petroleum University，Daqing，Heilongjiang 163318，China)