四川盆地南部构造页岩气储层压裂改造技术   总被引：6，自引：0，他引：6  

孙海成  汤达祯 《吉林大学学报(地球科学版)》2011,(Z1):34-39,68

在调研和学习国内外相关页岩气压裂改造技术的基础上,通过室内实验和研究,对四川盆地南部构造S2井页岩储层岩性特征、孔渗特征、天然裂缝发育特征进行了评价。针对S2井极低渗透率(0.000 18×10-3μm2)、天然裂缝和水平层理较发育,天然裂缝内充填有碳酸盐岩,同时吸附气含量较高、脆性程度高,压裂容易形成网络裂缝的特点,进行了压裂工作液体体系优选和压裂工艺优化,采取了大规模、大排量、大砂量、低砂比、减阻水压裂施工工艺,成功实现了页岩气储层大规模减阻水压裂施工;根据微地震显示,压裂改造体积达到了480×104 m3,具有明显的体积改造特征,获得较好的效果,日产10 000 m3。压后分析数据显示,在页岩气储层中,过长的关井时间有可能影响有限支撑剂铺置的裂缝整体导流能力,最终影响到产量。S2井压裂施工成功标志着国内在页岩气压裂施工工艺、压裂工作液体体系、裂缝监测等方面实现突破。  相似文献   

西页1井龙潭组海陆过渡相页岩含气性分析   总被引：2，自引：0，他引：2  

王中鹏  张金川  孙睿  刘昌为  杜晓瑞  卢亚亚 《地学前缘》2015,22(2):243-250

目前,国内外在海陆过渡相页岩含气性方面的相关研究较少。位于贵州省毕节地区黔西县境内的页岩气参数调查井西页1井揭示了黔西北地区上二叠统龙潭组海陆过渡相黑色碳质页岩发育特征及其含气性特点。通过有机地球化学实验,获取了西页1井的有机地化参数:TOC含量分布范围为0.4%~17.85%,平均值为4.25%;Ro分布范围为2.68%~3.48%,平均值为3.06%。钻、录、测井资料分析显示该井钻遇上二叠统龙潭组富有机质页岩层系厚度为148.85m,在钻进过程中,共有6层出现气显示。利用测井资料、现场解吸和等温吸附实验数据分析和计算,认为龙潭组海陆过渡相页岩含气页岩层段多,具有良好的吸附能力,得到总含气量为1.40~19.60m3/t。通过以上结果分析表明:西页1井所揭示的上二叠统海陆过渡相龙潭组含气页岩具有层段数量多、单层厚度小、有机质分段富集、热演化成熟度偏高等特点,且含气性较好,故该区海陆过渡相龙潭组地层具有较大的页岩气资源潜力。  相似文献   

页岩油资源定量评价中关键参数的选取与校正——以松辽盆地北部青山口组为例   总被引：1，自引：0，他引：1  

薛海涛  田善思  卢双舫  张文华  杜添添  穆国栋 《矿物岩石地球化学通报》2015,34(1)

页岩油资源评价过程中,常用热解参数(S1)反映含油性。由于实验关系,所测得的S1存在轻烃、重烃的损失,为更准确的对页岩油资源进行定量评价,本文通过有机质成烃动力学研究以及对样品抽提前后的热解参数进行对比,对S1进行轻、重烃补偿校正,获得泥页岩总含油率参数,根据泥页岩排烃门限确定其可动油含量参数(S1/TOC)。研究结果表明,松辽盆地北部青山口组泥页岩S1校正前后相差2~3倍,排烃门限对应的S1/TOC=75mg/g TOC,结合黏土矿物含量(表征可压裂性),优选出页岩油勘探开发有利区:青一段有利区主要集中在齐家古龙凹陷中北部及龙虎泡大安阶地中部,青二、三段集中在龙虎泡大安阶地中部与齐家古龙凹陷中南部。  相似文献   

Geochemical environment of Cenomanian - Turonian black shale deposition at Wunstorf (northern Germany)     

Almut Hetzel  Christian März  Christoph VogtHans-Jürgen Brumsack 《Cretaceous Research》2011,32(4):480-494

Major- and minor- element determinations were carried out on a high-resolution sample set obtained from a sediment drill core at Wunstorf (N. Germany). This study interval includes the black shale-bearing Hesseltal Formation associated with the Oceanic Anoxic Event 2 (OAE 2), also referred to as Cenomanian-Turonian Boundary Event (CTBE). Seven black shale packages, each containing several black shale layers, were defined by elevated TOC values, with black shale packages 1-4 deposited during OAE 2. Packages 5-7 extend above the level of the positive carbon-isotope excursion defining OAE 2, indicating that conditions favouring organic carbon burial must have prevailed longer in the Wunstorf Basin than elsewhere. Geochemical analyses revealed no significant differences between black shale packages deposited during and after OAE 2. Enrichment patterns of sulphur, iron and redox-sensitive and sulphide-forming trace metals point to suboxic to anoxic conditions existing at the sediment-water interface during black shale deposition, whereas sulphidic conditions prevailed deeper in the sediment. Variations in element/Al ratios follow cyclic patterns which are interpreted to represent climatically-induced changes in sediment supply. Reduced vertical mixing led to water-column stratification and caused black shale deposition.  相似文献   

Emerging coral diseases: a temperature‐driven process?          下载免费PDF全文

Aaron W. Miller  Laurie L. Richardson 《Marine Ecology》2015,36(3):278-291

In the last few decades there has been a surge in research focusing on coral disease. While climate change, specifically rising sea surface temperature, has been proposed as a major and growing driver of the emergence of marine diseases, to date a solid connection between disease epizootics and elevated sea surface temperature has not been established. However, a wealth of data now exists, compiled from many different perspectives, that may support such a connection. In this work we provide a comprehensive review targeting one coral disease, black band disease, that spans the infection process, pathobiology, and epizootiology, and links specific mechanisms of the disease process to increasing temperatures. This temperature‐driven pattern of infection can be expanded to include similar processes associated with other temperature‐related coral diseases. The conclusions presented here are based upon the results of many studies using a diverse suite of approaches that have been synthesized to argue that the emergence and continuing spread of black band disease is linked to warming sea surface temperatures. In summary, as global ocean temperatures increase seasonally and over decades, the environment shifts to become more favorable for the growth of potentially pathogenic microorganisms endemic to the immediate environment of the reef. The increase in the relative number of potential pathogens in the microbial community produces microenvironments conducive to the growth of other potential pathogens, leading to infection by a polymicrobial consortium. This consortium is easily perturbed by a (seasonal) temperature decrease, but remains associated with the coral host and can be reactivated with a subsequent seasonal increase in temperature, resulting in a cycle of temperature‐dependent disease emergence.  相似文献   

The origin,type and preservation of organic matter of the Barremian–Aptian organic-rich shales in the Muglad Basin,Southern Sudan,and their relation to paleoenvironmental and paleoclimate conditions     

《Marine and Petroleum Geology》2015

Barremian–Aptian organic-rich shales from Abu Gabra Formation in the Muglad Basin were analysed using geochemical and petrographic analyses. These analyses were used to define the origin, type of organic matters and the influencing factors of diagenesis, including organic matter input and preservation, and their relation to paleoenvironmental and paleoclimate conditions. The bulk geochemical characteristics indicated that the organic-rich shales were deposited in a lacustrine environment with seawater influence under suboxic conditions. Their pyrolysis hydrogen index (HI) data provide evidence for a major contribution by Type I/II kerogen with HI values of >400 mg HC/g TOC and a minor Type II/III contribution with HI values <400 mg HC/g TOC. This is confirmed by kerogen microscopy, whereby the kerogen is characterized by large amounts of structured algae (Botryococcus) and structureless (amorphous) with a minor terrigenous organic matter input. An enhanced biological productivity within the photic zone of the water columns is also detected. The increased biological productivity in the organic-rich shales may be related to enhanced semi-arid/humid to humid-warm climate conditions. Therefore, a high bio-productivity in combination with good organic matter preservation favoured by enhanced algae sizes are suggested as the OM enrichment mechanisms within the studied basin.  相似文献   

Oil migration driven by exhumation of the Canol Formation oil shale: A new conceptual model for the Norman Wells oil field,northwestern Canada     

《Marine and Petroleum Geology》2015

Thermal history, petroleum system, structural, and tectonic constraints are reviewed and integrated in order to derive a new conceptual model for the Norman Wells oil field, and a new play type for tectonically active foreland regions. The thermal history recorded by Devonian rocks suggests that source rocks experienced peak thermal conditions in the Triassic–Jurassic, during which time oil was likely generated. After initial oil generation and expulsion, the Canol Formation oil shale retained a certain fraction of hydrocarbons. The shallow reservoir (650–350 m) is a Devonian carbonate bank overlain by the Canol Formation and resides within a hanging wall block of the Norman Range thrust fault. Both reservoir and source rocks are naturally fractured and have produced high API non-biodegraded oil. Thrust faults in the region formed after the Paleocene, and a structural cross-section of the field shows that the source and reservoir rocks at Norman Wells have been exhumed by over 1 km since then.The key proposition of the exhumation model is that as Canol Formation rocks underwent thrust-driven exhumation, they crossed a ductile–brittle transition zone and dip-oriented fractures formed sympathetic to the thrust fault. The combination of pore overpressure and new dip-directed subvertical fractures liberated oil from the Canol Formation and allowed for up-dip oil migration. Reservoir rocks were similarly fractured and improved permeability enhanced charging and pooling of oil. GPS and seismicity data indicate that strain transfer across the northern Cordillera is a response to accretion of the Yakutat terrane along the northern Pacific margin of North America, which is also the probable driving force for foreland shortening and rock exhumation at Norman Wells.  相似文献   

Multiple controls on the paleoenvironment of the Early Cambrian marine black shales in the Sichuan Basin,SW China: Geochemical and organic carbon isotopic evidence     

《Marine and Petroleum Geology》2015

In order to understand the paleoenvironment of the Early Cambrian black shale deposition in the western part of the Yangtze Block, geochemical and organic carbon isotopic studies have been performed on two wells that have drilled through the Qiongzhusi Formation in the central and southeastern parts of Sichuan Basin. It shows that the lowest part of the Qiongzhusi Formation has high TOC abundance, while the middle and upper parts display relative low TOC content. Redox-sensitive element (Mo) and trace elemental redox indices (e.g., Ni/Co, V/Cr, U/Th and V/(V + Ni)) suggest that the high-TOC layers were deposited under anoxic conditions, whereas the low-TOC layers under relatively dysoxic/oxic conditions. The relationship of the enrichment factors of Mo and U further shows a transition from suboxic low-TOC layers to euxinic high-TOC layers. On the basis of the Mo-TOC relationship, the Qiongzhusi Formation black shales were deposited in a basin under moderately restricted conditions. Organic carbon isotopes display temporal variations in the Qiongzhusi Formation, with a positive excursion of δ¹³C_org values in the lower part and a continuous positive shift in the middle and upper parts. All these geochemical and isotopic criteria indicate a paleoenvironmental change from bottom anoxic to middle and upper dysoxic/oxic conditions for the Qiongzhusi Formation black shales. The correlation of organic carbon isotopic data for the Lower Cambrian black shales in different regions of the Yangtze Block shows consistent positive excursion of δ¹³C_org values in the lower part for each section. This excursion can be ascribed to the widespread Early Cambrian transgression in the Yangtze Block, under which black shales were deposited.  相似文献   

超压对川东南地区五峰组-龙马溪组页岩储层影响分析     

刘若冰 《沉积学报》2015,33(4):817-827

四川盆地东南部保存条件较好的五峰组-龙马溪组页岩普遍存在超压,且在其他地质条件相同的情况下,超压页岩储层相对于常压、低压储层具有更高的孔隙度.研究表明,富有机质页岩在适中的热演化过程中,由于烃类的大量生成,形成较多有机质孔隙,增加了页岩储层储集空间;另一方面,烃类大量生成造成的超压对页岩储层储集空间保存具有至关重要的作用.川东南五峰组-龙马溪组优质页岩储层孔隙以有机质孔、黏土矿物孔等塑性孔为主,且缺少刚性矿物颗粒支撑,易被上覆地层有效应力压实.但超压的存在对于页岩储层具有保护作用,抵消了上覆地层有效应力对页岩储层的机械压实,从而使已形成的页岩孔隙保存下来,使页岩储集空间得以保留.研究超压对页岩储层孔隙度影响机制以及超压页岩储层发育模式对于四川盆地五峰组-龙马溪组页岩气勘探、开发具有重要意义.  相似文献   

页岩孔隙度测量实验方法分析与评价   总被引：2，自引：1，他引：1  

杨巍  薛莲花  唐俊  吕成福  徐勇  杨爽  陈国俊 《沉积学报》2015,33(6):1258-1264

页岩气是目前国内外非常规油气领域研究的热点,有效的页岩孔隙度值是评价页岩储层物性的重要参数。由于页岩本身具有易碎的特点,导致钻取柱体样品难度大,很多学者采用碎样法计算孔隙度,但碎样法与柱体法的差别及测定结果的有效性并未见相关研究成果。本文对相同样品通过三种不同方法:氦气膨胀法测孔隙度(柱体),真、视密度法及低温氮气吸附实验法(样品粉碎至40~60目)分别计算孔隙度。结果发现三种方法测定的三组孔隙度数值不同,每种方法在样品制备上及实验方法的差别是影响实验结果的主要因素,为检验三组孔隙度值的有效性,采用数理统计中的单因素方差分析法进行分析,结果表明页岩柱体与粉碎至40~60目范围内的页岩样品测量的孔隙度值虽有差别,但在有效范围内,具有一致性。但是将页岩粉碎后,页岩中的有效孔隙变化程度较大,故用柱体测定的有效孔隙度法优于其他两种碎样方法。  相似文献