Deep shale reservoirs in the southern Sichuan Basin have undergone strong tectonic reworking, producing pore structure heterogeneity that affects reservoir quality and hydrocarbon preservation. In this study, shales with different deformation intensities are analyzed using field emission scanning electron microscopy (FE-SEM), low-pressure nitrogen gas adsorption (LP-N2GA) and fractal analysis to investigate tectonic control on pore–fracture evolution and fractal characteristics. Weakly deformed shales are dominated by intraparticle pores and regular organic matter (OM) pores, whereas strongly deformed shales develop abundant interparticle pores and microfractures along brittle mineral boundaries with irregular, preferentially oriented OM pores. The large-pore fractal dimension (D2) consistently exceeds the small-pore fractal dimension (D1) in both wells, indicating greater adsorption-related structural complexity of larger pores. Strongly deformed shales exhibit a higher mean box-counting fractal dimension (Db), indicating greater geometric complexity of OM pores. Supervised machine-learning image analysis reveals pore-size differentiation associated with deformation intensity. Intense tectonic compression may cause some 80–350 nm pores to contract, whereas localized pressure release and shear-induced dilation may promote pore expansion and fracture propagation, producing pronounced multiscale heterogeneity. Overall, stable overpressure preserves the primary pore system in weakly deformed zones, whereas compressive deformation and localized pressure release drive the coupled evolution of pore structure and fractal characteristics, with potential implications for shale gas storage and preservation.

Hydraulic fracture growth is significantly influenced by the minimum horizontal principal stress gradient and the fracturing fluid pressure gradient. However, these gradients are often neglected in scaled physical modeling experiments due to difficulties in reproducing them. This study uses centrifugal hypergravity to simulate both gradients and investigate their effects on fracture propagation. Artificial mortar specimens (/200 mm x 400 mm) are fractured under 1g (normal gravity), 50g, and 100g. Results show that compared to 1g, fractures under 50g and 100g exhibit increasingly uneven propagation, with higher gvalues leading to greater asymmetry. To interpret this, a theoretical analysis based on fracture mechanics is conducted. When the fluid pressure gradient exceeds the stress gradient, a positive net gradient is generated, increasing net pressure at the lower fracture tip. This raises the stress intensity factor at the lower tip, promoting downward growth. As g increases, the disparity becomes more significant, resulting in greater fracture deviation. In conclusion, this study, for the first time, has verified and explained that the net gradient can change the propagation of hydraulic fractures, providing important guidance for wellbore placement under stress gradients.

Despite the shale revolution triggering global shale oil and gas exploration, our understanding of the sedimentary environments of deep-water organic-matter-rich shale remains unclear. The sedimentary environment and facies of some siliceous shales at the bottom of the Longmaxi Formation in the Weiyuan area of the Sichuan Basin, China, were therefore analyzed. Nano-resolution petrological characterization and genesis analysis of the siliceous shales studied were conducted using nano-resolution petrologic image datasets. We identified these siliceous shales as microbial mats formed by deep-water traction current sedimentation. The microbial mats’ formation and burial diagenesis processes were divided into seven stages. The silt-grade bioclastic carpet deposits initially, colonizing mud-grade siliceous microbes and forming the siliceous microbial mat. Subsequently, carbohydrate-rich microbes thrive in sediment voids, forming the carbohydrate-rich microbial mat. Additionally, SOM undergoes four stages of burial diagenesis process, progressing from kerogens to pre-oil bitumen generation and ultimately transforming into porous pyrobitumen and nonporous pyrobitumen. This study will improve the understanding of deep-water traction current sedimentation and has implications for guiding shale gas exploration and development.

Three nano-resolution petrological microtextures were discovered in the siliceous shale at the bottom of the Longmaxi Formation in the Zigong area, Sichuan Basin. Based on observations of the occurrences of the minerals, organic matter, and organic matter pores in the different microtextures and analysis of their relationships by means of nano-resolution petrological image datasets obtained using the Modular Automated Processing System (MAPS 3.18), the formation mechanism of the siliceous shale was studied. The results show that the strong modification of clay-rich sediments by a deep-water traction current was the basis for the formation of the siliceous shale. The clay-rich sediments were converted into flocculent sediments rich in oxygen and nutrients via agitation and transport by the deep-water traction current, providing space and a material basis for microbes to flourish. Under the continuous activity of the deep-water traction current, the clay-rich sediments were transformed into microbial mats, in which in situ terrigenous detrital quartz and feldspar, endogenous detrital calcite, authigenic dolomite, and dolomite ringed by ferrodolomite were scattered. During the burial stage, the microbial mats were lithified into the siliceous shale composed of three petrological microtextures. Microtexture I was mainly transformed by microbes. Microtexture II was formed via lithification of the residual clay-rich sediments. Microtexture III was composed of migratory organic matter filling hydrocarbon-generating pressurized fractures. Due to the universality of deep-water traction flow and the diversity of microbes in deep-water sediments, we firmly believe that more and more deep-water microbialites will be discovered worldwide through systematic characterization of nano-resolution petrology with the booming development of the shale gas industry.

For the development of shale gas, the accurate prediction of estimated ultimate recovery (EUR) has invariably been a hot and arduous issue that has attracted abundant attention from researchers. However, the intricate relationship between EUR and economic benefits of shale gas wells is frequently disregarded. Therefore, based on the basic geological and engineering parameters, this study carried out a joint multi-task modeling of investment cost and EUR evaluation, and creatively constituted a techno-economic integration evaluation framework for shale gas wells with internal rate of return (IRR) as the economic benefit evaluation target. Furthermore, the interaction graphs of investment cost and EUR on IRR are delineated to intuitively exemplify the relationship between EUR and economic benefits (IRR). The validity of the model is verified by the field data from 231 wells. The results show that the techno-economic integration evaluation framework of Blendstacking, which integrates multi-task joint modeling and integrated learning, can reliably evaluate investment costs and EUR. Concurrently, based on the evaluation results, the accurate prediction of IRR is realized. The mean prediction errors of investment cost and EUR are inferior to 50 ×104USD and 1400 ×104m3, respectively, and the mean error of IRR is regulated within 2.0%. This work can quickly and effectively predict the economic benefits of gas wells under complex geological and engineering factors, which facilitates expeditiously developing decision making. The research method can be extended to the economic benefit evaluation of other instance well datasets.

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Natural gas from shale gas reservoirs has been an important contributor for reserve growth, deliverability construction, and profits growth in natural gas industry in the world. Hydraulic fracturing is commonly required in the shale gas commercial development, and thus understanding the present-day in situ stress field is greatly significant for the hydraulic fracturing and efficient development in shale gas reservoirs. However, there are no systematic investigations on the present-day in situ stress field in the Haiba Block from the Sichuan Basin, South China. In this study, the present-day in situ stress orientations and magnitudes in shale reservoir of Haiba Block are investigated based on the well interpretations from borehole image log and geomechanical modeling. Then, the effects of stresses on hydraulic fracturing, horizontal wells, and natural fracture reactivation were discussed. The results indicate that the horizontal maximum principal stress (SHmax) orientation is mainly in the NE-SW-trending, NW-SE-trending, and WNW-ESE-trending in the Haiba Block. The magnitudes of horizontal maximum and minimum principal stresses are 13.5 MPa~85.5 MPa and 2.8 MPa~31.6 MPa, respectively. In the Haiba Block, the differential stress is generally low in the northern part, which indicates that complex hydraulic fracture networks may be produced. While the natural fractures are generally stable under the present-day in situ stress field. When the increase of pore pressure gradient is about 30 KPa/m, nearly all natural fractures in the Longmaxi Formation may be reactivated. The results can provide the insights into a better understanding of the present-day in situ stress distribution so as to optimize perforation orientation, hydraulic fracturing design, and enhance gas production in shale gas reservoirs.

Accurate prediction of shale gas well production and estimated ultimate recovery (EUR) is always a difficult and hot spot in shale gas development. In particular, the production and EUR prediction of shale gas wells in new production blocks are faced with the lack of field gas well data and the difficulty of model development. In view of the above problems, this study proposes a new deep transfer learning strategy, which uses transfer component analysis (TCA) and deep neural network (DNN) to achieve shale gas well production and EUR prediction across formations/blocks. The feature extractor based on TCA can narrow the input feature distribution of the source and the target domains. The neural network model can be used to establish a domain -adaptive transfer learning model without the prediction performance degradation caused by distribution offset. Validity and accuracy of the model were analyzed using gas well data from Weiyuan and Luzhou blocks in Sichuan Basin, China. The results appear that the reasonable application of TCA can greatly improve the prediction performance of shale gas well transfer learning model. For data sets of the same size, compared with the transfer learning model developed by classical machine learning algorithms, the proposed neural network-based transfer learning model can significantly improve the accuracy of production prediction across formations/ blocks. In addition, the proposed model can also be extended to other types of oil and gas production prediction tasks cross formations/blocks.

黑色页岩甜点类型、识别标准及分布规律直接影响勘探层位优选及钻井靶点设计.为此,以四川盆地南部(以下简称川南地区)上奥陶统五峰组—下志留统龙马溪组海相黑色页岩为例,结合岩石学、层序地层学等理论,综合分析了相对海平面变化、裂缝类型与页岩储层品质之间的关系.研究结果表明:①川南地区五峰组—龙马溪组黑色页岩可划分出沉积型和裂缝型 2 类甜点,其中,沉积型甜点细分为早期海进型、快速海进型、晚期海进型和近滨海进型 4 类,裂缝型甜点分为网状微裂缝型和网状宏观裂缝型2 类.②早期海进型和近滨海进型以半远洋沉积为主,粉砂和黏土混杂堆积,TOC较低;快速海进型以远洋沉积为主,微晶石英发育,TOC高,有机孔发育;晚期海进型以等深流沉积为主,TOC偏低,无机孔相对发育.③裂缝型甜点储层宏观裂缝和微裂缝发育,但基质孔隙度和渗透率不一定高.④早期海进型甜点分布于笔石带WF2—WF3,快速海进型甜点分布于笔石带LM1,晚期海进型甜点分布于笔石带LM2—LM4 及LM5,近滨海进型甜点分布于笔石带LM1—LM4,网状微裂缝型甜点主要分布于笔石带LM1,网状宏观裂缝型甜点的分布受断层规模和构造转换带变形程度控制.⑤笔石带LM6—LM8 黏土矿物含量高、成岩收缩缝发育的位置可形成网状微裂缝型甜点;构造转换带与调节带具有弱变形与弱改造特征,网状宏观裂缝发育,可形成网状宏观裂缝型甜点.结论认为,川南地区快速海进型和近滨海进型甜点勘探已取得重大突破,早期海进型和晚期海进型是下一步勘探的重要目标;以沉积学及裂缝特征为判识依据的甜点类型划分为页岩气深化勘探和效益开发提供了理论支撑.

High graphitization is responsible for low-resistivity shale development with poor reservoir quality. This paper provides an explanation of organic matter graphitization and determines the impact of high graphite content on low-resistivity shale reservoir quality at the Wufeng-Longmaxi Formation in the Southern Sichuan Basin. Fine veins are frequently developed at shale samples with Ro > 3.5%, graphitized organic matter > 25%, and resistivity < 5 Ω•m, which are dominated by three mineral assemblages: brunsvigite, barite-hyalophane-barium feldspar-potassium feldspar-anhydrite, and calcite-ankerite. These filling minerals are characterized by an Eu positive anomaly and high Ba, Fe, and Mn contents, suggesting that low-resistivity shale was modified by magmatic-related low-temperature hydrothermal fluid. Temperature measurements of brine inclusions and a semi-empirical geothermometer of chlorite show that low-temperature hydrothermal fluid experienced the chlorite stage (150–180 °C), the low-sulfidation stage (120–150 °C), and the low-temperature calcitization stage. Paleozoic fault systems and late Permian hydrothermal activities associated with the Emeishan mantle plume control the graphitization of low-resistivity shale. The water formation and seawater infiltrated into the deep crust along the Paleozoic basement faults under gravity, developing alkaline hot brine through mantle plume heating and then causing a water-rock reaction with basement rocks. They migrated upward along deep and large Paleozoic faults through convective thermal circulation in the Tiangongtang area, the Shuanglong-Luochang area, and the Xuyong area. Cation exchange and redox reactions occurred during the interaction between high-temperature hydrothermal fluid and cool wall rocks. The migration of alkaline hot brine via the Wufeng-Longmaxi shale introduced a subsequent water-rock reaction, resulting in the development of hydrothermal mineral assemblages that intricately filled fractures. It increased formation temperature and enhanced thermal maturity and graphitization of organic matter at the Wufeng-Longmaxi low-resistivity shale, resulting in a wide distribution of low-resistivity shale at the Changning Block.

"甜点"是页岩气储层中相对高产的层位和区域,地质甜点、工程甜点和综合甜点的合理预测及评价,是页岩气规模效益开发的基础之一.针对页岩气储层甜点多参数综合定量评价,引入层次分析法,综合地质与工程要素,基于高分辨率三维地质模型,形成了地质工程一体化页岩气甜点评价的新方法,进行页岩气储层甜点区域的预测.首先,综合前人研究成果,建立了一种页岩气地质甜点、工程甜点和综合甜点评价的指标体系;随后,设计了基于层次分析法的页岩气储层地质工程一体化甜点评价方法的技术路线;最后,采用昭通页岩气田海坝区块X井区实例数据,基于该区域高分辨率三维地质模型,根据形成的甜点评价方法,进行了研究区地质甜点、工程甜点和综合甜点的预测和评价.结果表明,该方法可以综合地质和工程的多种评价指标,实现了昭通页岩气田海坝区块X井区地质甜点、工程甜点和综合甜点的评价,评价的甜点区域主要分布在奥陶系五峰组,志留系龙马溪组一段1亚段1小层、2小层和3小层(L111,L112,L113),4小层(L114)相对较少.基于层次分析法的页岩气储层地质工程一体化甜点评价,可以将定性分析和定量分析相结合,为页岩气甜点的圈定提供了一种新思路,提高了甜点评价结果的合理性和准确性.

Deep shale gas (burial depth > 3500 m) in the Longmaxi Formation of southern Sichuan Province will be the primary target for exploration and development in China for a relatively long period. However, the lack of a physical basis for the “sweet-spots” seismic and well-logging prediction is caused by uncertainty in the rock physical properties of deep shale gas in the research area. Acoustic and hardness measurements were performed on shale samples from a deep layer of the Longmaxi Formation in southern Sichuan. Microtextural characteristics of the shale samples were also analyzed by conventional optical microscopy and scanning electron microscopy. Based on these measurements, the rock physical properties of the shale samples and control factors are discussed. It is shown that the deep shale samples have similar properties to the shallow shale in mineral composition, microtexture, and pore type. However, the organic pore in deep shale samples is relatively undeveloped, while the dissolved pores are more developed. For high-quality shale samples (total organic content > 2%), crystal quartz of biological origin forms the framework of rock samples, resulting in effective dynamic and static properties, reflecting the elastic behavior of rigid quartz aggregates. For organic-lean samples (total organic content < 2%), orientated detrital clay particles take the role of load-bearing grains. Therefore, these shale samples’ overall rock physical properties are mainly controlled by the elastic properties of “soft” clay. The load-bearing grain variation from organic-rich shale samples to organic-lean samples results in an overturned “V”-type change in terms of velocity versus content. Organic-rich shale samples also show an apparent low Poisson’s ratio. Organic-rich shale has a slight velocity–porosity trend, while organic-lean shale shows a significant velocity–porosity trend. In addition, due to the difference in rock microtexture between organic-rich and organic-lean shale, these two kinds of reservoir rocks can be discriminated in cross plots of P-wave impedance versus Poisson’s ratio and Young’s modulus versus Poisson’s ratio. Change in hardness also reflects the control of microtexture, and shale samples with biological-origin quartz as load-bearing grains show higher hardness and brittleness. However, the variation in quartz content has less of an impact on hardness and brittleness in shale samples with clay as the load-bearing grain. Our results provide an experimental basis for the geophysical identification and prediction of deep shale gas layers.

根据钻井、测井、岩心描述、岩石薄片鉴定和岩心实验分析资料,结合现代海洋的沉积特征,研究了四川盆地南部泸州地区奥陶系五峰组—志留系龙马溪组富有机质页岩中的矿物含量分布、岩相特征和沉积类型,划分了深水陆棚的沉积微相和微地貌,分析了深水陆棚沉积微相-微地貌对储层的影响.研究结果表明:①研究区五峰组—龙马溪组富有机质页岩的陆源碎屑来自北侧川中水下高地,其岩相主要包括硅质页岩、含黏土硅质页岩和混合页岩3种类型.②目的层的沉积类型以半远洋沉积和浊流沉积为主.③深水陆棚沉积微相可细分为钙质陆棚、钙-硅质陆棚、钙-硅-泥混合陆棚、硅-泥质陆棚、硅质陆棚和富泥扇6种类型,在研究区以发育硅质陆棚、硅-泥质陆棚和钙-硅-泥混合陆棚为主;沉积微地貌可细分为陆棚高地、陆棚斜坡、陆棚沟、陆棚丘和陆棚平原5种类型,在研究区以发育陆棚平原和陆棚斜坡为主.④深水陆棚沉积微相通过控制储集能力而控制富有机质页岩的储层质量,钙-硅-泥混合陆棚和硅质陆棚具有最好的储层品质;沉积微地貌通过控制富有机质页岩的厚度从而影响页岩储层质量,其中以陆棚平原中储层厚度最大.⑤在深水陆棚环境,随着沉积水体加深,沉积微地貌的演化由陆棚高地经陆棚斜坡(陆棚沟、陆棚丘)过渡到陆棚平原(陆棚丘),沉积微相的演化由钙-硅质陆棚经钙-硅-泥混合陆棚过渡到硅-泥质陆棚(富泥扇),并最终演化为硅质陆棚.深水陆棚沉积微相模式可为深层富有机质页岩的储层评价与预测提供科学支撑.⑥深水陆棚富有机质页岩沉积在陆棚边缘,其沉积水深可超过200m.

海相页岩古地理编图和深水陆棚亚相微相细分一直是细粒沉积学研究的热点和难点.以川南泸州地区五峰组—龙一41小层为编图单元,通过页岩编图关键单因素的选取和典型钻井矿物组分测井数据的统计分析,编制了关键单因素图件.在此基础上,通过深水陆棚亚相各微相划分标准的确定及多因素图件综合分析,编制了海相页岩定量古地理图.结果表明:1)海相页岩定量古地理编图的关键单因素是地层厚度(m)、碳酸盐矿物含量(％)、石英含量(％)和黏土矿物含量(％).其中,地层厚度(m)反映了该地层单元在区域上的分布范围、厚度变化及沉积时期的大地构造背景;碳酸盐矿物含量(％)及分布能够反映古水深,水深越浅,碳酸盐矿物含量(％)越高;石英含量(％)及分布主要受古水深控制,水深越大,石英含量越高;黏土矿物含量(％)和分布可以反映古物源方向,黏土矿物含量越高,受陆源碎屑影响越大.2)依据海相页岩的碳酸盐矿物含量(％)、石英含量(％)和黏土矿物含量(％),深水陆棚亚相可划分出深水斜坡、深水洼地、重力流沉积和深水平原4种沉积微相.其中,深水斜坡碳酸盐含量最高(15％～20％),深水洼地石英含量最高(>55％),重力流沉积黏土矿物含量最高(>40％),深水平原各矿物含量介于其他微相之间.3)五峰组—龙一41小层发育时期,川南泸州地区发育深水斜坡、重力流沉积、深水洼地和深水平原4种沉积微相,整体呈"3高1洼1复合体"的分布格局,其中,深水斜坡分布于研究区西北部和东北部,重力流沉积发育于研究区东南部,深水洼地发育于研究区中部,其他地区发育深水平原.沉积微相分布是该时期古地形及古构造活动的产物.

上扬子地区四川盆地南部威远—泸州地区上奥陶统凯迪阶五峰组和志留系底部兰多维列统龙马溪组黑色笔石页岩沉积于滞留缺氧海底且富含有机质,是页岩气的主产层位,介于五峰组和龙马溪组之间的奥陶系顶部赫南特阶观音桥组通常是含腕足类以及三叶虫的灰岩沉积,其化石组成是冈瓦纳冰川事件最盛期在低纬度陆表海区的产物,岩石学微相特征研究能进一步诠释当时海底沉积环境.本文根据威远地区的W2、W4H10井,泸州地区的L2井、L4井、L5井、L6井、L7井、L8井、L9井观音桥组微相鉴定识别生物多样性,除常见的Hirnantia腕足动物群、三叶虫Dalmanitina等壳相化石外,还出现海百合、腹足类Homotoma、双壳类、海绵动物碎片和虫管遗迹化石Chondrites(丛藻迹),其化石组成记录了该层位的生物多样性.观音桥组沉积时该区海底富氧环境有利于底栖动物生存,远岸区海底水动力弱,化石粒度偏细且部分化石破碎程度高,未见大量复体珊瑚和钙藻等典型暖水区化石,反映出远岸相观音桥组海底水温可能偏低.

通过对威远地区14口评价井或导眼井五峰组—龙马溪组地层开展系统的笔石生物地层、岩相地层、测井响应、地球化学、元素地球化学等特征分析,证实了威远地区五峰组—龙马溪组古隆起的发育,指出古隆起发育控制页岩的厚度及岩相展布,明确优质页岩展布受古隆起发育控制,并提出水平井井位优化部署建议.主要结论如下:1)从生物地层、岩性地层、电性特征、地层厚度等方面证实在Z4-Z1—WY1—W5—WX井一带存在(水下)古隆起;2)不同时期地层分布及岩相主要受古隆起发育控制,隆起区及周边地层厚度薄,黏土矿物或碳酸盐矿物含量高,坳陷区沉积厚度大,硅质矿物含量高;3)威远地区五峰组页岩沉积期物源多来自其西部或北部,鲁丹阶早期以生物成因石英为主,物源较少,鲁丹阶晚期物源可能来自川南的黔中古陆,不同的物源方向意味着沉积体系的变化;4)鲁丹阶早期(LM1～LM3)地层储层品质最优,产量高,其储层参数平面展布受隆起发育控制,拗陷区域储层品质最好.建议以鲁丹阶早期地层为目标靶体实施水平井,优先部署该层段厚度较大区域水平井,尽量避开隆起发育区.

通过氩离子抛光结合扫描电镜技术对四川盆地五峰组-龙马溪组放射虫硅质页岩有机质类型与有机孔的配置关系进行研究.结果表明:3种类型的过成熟有机质与有机孔的配置关系清晰地记录沉积有机黏粒复合体的成岩演化历程;岩化阶段,沉积有机黏粒复合体转化为干酪根黏粒复合体;低熟阶段,干酪根黏粒复合体转化为油前沥青黏粒复合体和迁移油前沥青;成熟阶段,油前沥青降解生成石油,相应地油前沥青黏粒复合体转化为固体沥青黏粒复合体,迁移油前沥青转化为固体沥青;高—过成熟阶段,有机质裂解产生湿气和干气,固体沥青黏粒复合体转化为焦沥青黏粒复合体,固体沥青化迁移油前沥青转化为焦沥青,石油也转化为焦沥青;焦沥青黏粒复合体和焦沥青化迁移油前沥青发育有机孔,即Ⅰ类和Ⅱ类有机质;焦沥青化石油缺乏有机孔,即Ⅲ类有机质;建议推广利用放射虫硅质页岩的岩石学特征研究页岩储层有机质类型和有机孔配置关系,并将有机黏粒复合体作为沉积有机质的重要赋存形式来判识原地有机质与迁移有机质.

Both complete and uncompleted radiolarian siliceous shells were developed at Wufeng-Longmaxi radiolarian siliceous shale laminae in Sichuan Basin. Micro- and ultra-micropetrological observation suggests that they were successively filled by calcite, pyrite and organic–silicon complex, where pyrite and organic–silicon complex filled dissolved pores associated with calcite during sedimentation. Calcite was derived from calcium carbonate produced by microbial activities at the seawater surface. The environment of radiolarian siliceous shell cavities, which was suitable for sulfate reducing bacterial growth or dissolved hydrogen sulfide reducing Fe3+, contributed positively to pyrite development. Organic–silicon complex development was related to microorganism metabolism that was an important silica source. Honeycomb-like organic pores were developed in cavities with complete shells, but were not developed in cavities with uncompleted shells. This is because the latter could not withstand overburden pressure compared with the former. The only approach to figure out organic pore carriers and understand sequences and development processes of minerals and organic matter is to select weakly compacted radiolarian siliceous shale laminae to carry out micro- and ultra-micropetrological observation and geochemical testing via various technologies.

The characteristics, formation mechanisms, and influences on physical properties of carbonate minerals in shale reservoirs of Wufeng-Longmaxi formations in Sichuan Basin are systematically investigated by utilizing electron probe microscope with spectrometer and energy spectrometer, combined with physical properties and whole rock X-diffraction and organic carbon data. The research yielded the findings that follow: First, the main carbonate minerals are calcite, dolomite, and ferriferous dolomite. Calcite is a single mineral that fills the siliceous shell cavity of radiolarians and exists between mineral particles. Ferriferous dolomite always rings dolomite, which is a single mineral that is present among mineral particles and aggregates. Second, calcite is produced by microorganisms that secrete calcium carbonate in the surface of seawater. The siliceous skeleton cavity of radiolarian and seawater both precipitate calcite, which partially dissolves while settling in seawater before depositing on the seabed and being preserved by burial. Thirdly, the dolomite is a diagenetic mineral formed on the water–sediment interface with physiological activities of sulfate bacteria, and the ferriferous dolomite is produced by methanogenic metabolism during the initial burial of muddy sediments. Fourthly, organic carbon, pyrite, quartz, and clay minerals are closely related to reservoir physical properties, while carbonate has no effect on porosity and permeability as a whole. Future research on shale reservoir diagenesis should make use of the in-situ detection and element area scanning, in particular with the spectrogram from electron probe microscope technology, which provides typical petrological evidences for the study of characteristics, formation mechanism, and influence on physical properties of carbonate minerals in shale reservoirs.

泥页岩约占沉积岩三分之二,不仅记录着丰富的地质信息,同时也是化石燃料、金属与非金属等矿产的重要物质来源,但目前它们的沉积过程与形成机理研究仍处于探索阶段.沉积物理模拟实验是模拟沉积物沉积过程、揭示其形成机理的有效手段之一.冲积扇、三角洲、重力流等粗粒沉积物一直是沉积物理模拟的重要研究对象,但随着非常规油气大规模勘探开发,泥页岩等细粒沉积逐渐成为研究热点,相关沉积物理模拟也取得了一些重要进展,主要包括泥页岩沉积机理、砂质纹层沉积机理、透镜状纹层沉积机理和细粒碳酸盐岩沉积机理等四个方面,这些新进展正在改变着传统认识.在此基础上,展望了泥页岩沉积物理模拟发展趋势,未来将大力推动非常规油气沉积学创新发展,并对全球气候变化、岩相古地理、地质资源开发、水利工程建设、生态环境保护和自然灾害防治等领域产生重要影响.