塔河油田碎屑岩油气运聚模拟及潜力区优选     

冯兴强  宋海明 《地质力学学报》2020,26(6):892-900

为了系统研究塔河油田碎屑岩油气运聚过程，针对研究区目的层的地质特征，文章采用流径和逾渗综合方法进行油气运聚模拟分析。该方法基于断裂-砂体输导格架来开展油气运聚模拟，首先通过断层的分级、分期研究，结合实际资料形成了断层开启性判别标准，进而建立断层输导格架模型；综合使用压实曲线和孔渗关系，利用相控建模技术建立砂体输导格架模型。在断裂-砂体输导格架基础上开展了油气运聚模拟，模拟结果与现有的油气藏吻合较好，表明流径与逾渗综合法是一种模拟研究区目的层油气运聚过程的有效方法。同时，利用模拟结果，明确了主要目的层的潜力区域，对研究区碎屑岩的勘探部署有重要意义和实际价值。   相似文献   

西南煤系地层山区采动型崩滑灾害研究关键问题     

李军  褚宏亮  李滨  贺凯  高杨 《中国岩溶》2020,39(4):453-466

文章在分析采矿型崩滑灾害发育特征的基础上，得出西南煤系地层山区地下采动型崩滑灾害常发生在层状碳酸盐岩与碎屑岩地层组成的褶皱翼部和核部的陡崖带上，与地形地貌、地层结构与地下采矿工程活动等因素关系密切，并指出薄矿层开采诱发大型山体崩滑灾害的具体过程:①采空后覆岩顶板塌落—覆岩顶板离层，采空区上覆岩层内部及层间自下而上应力传递；②地下水运移通道形成，并加快更大范围岩体结构破坏及扩展，加速了岩体结构面的松动与破坏；③上覆岩层不均匀沉降导致坡脚压裂，山体大型岩体结构面逐渐拉剪或压剪变形扩展，最终山体发生累积损伤与大规模崩滑灾害。此外，传统经验公式的计算方法对此类采矿型崩滑灾害已不适用，建议开展西南煤系地层山区地质结构与地下采动诱发崩滑灾害的相互作用关系、薄矿层采空区上部山体累积断裂损伤—岩体松动、裂隙扩展-岩溶管道流、裂隙流变化的链式响应机制、地下采动型崩滑灾害评价方法等关键科学问题的研究，以推动采矿型地质灾害防灾减灾工作的发展。   相似文献   

Novel Hybrid Integration Approach of Bagging-Based Fisher’s Linear Discriminant Function for Groundwater Potential Analysis     

Chen  Wei  Pradhan  Biswajeet  Li  Shaojun  Shahabi  Himan  Rizeei  Hossein Mojaddadi  Hou  Enke  Wang  Shengquan 《Natural Resources Research》2019,28(4):1239-1258

Natural Resources Research - Groundwater is a vital water source in the rural and urban areas of developing and developed nations. In this study, a novel hybrid integration approach of...  相似文献   

Geochemical characteristics and sedimentary environment of the Middle Devonian organic-rich shales in the Northwest of Guizhong Depression,Southwest China     

《China Geology》2020,3(4):567-574

In order to figure out the redox conditions and paleo-sedimentary environment of the Middle Devonian shales in the northwest of Guizhong Depression, the trace element analysis was conducted on the Middle Devonian cores (320.35–938.50 m) of the typical shale gas investigation well (GY-1) at a 1.50 m sampling interval through X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). According to the test result, the average values of V/(V+Ni), V/Cr and Ni/Co in Nabiao formation (Fm.) are larger than 0.67, 4.65 and 7.71 respectively, and Nabiao Fm. is rich in biological assemblages such as tabasheer, ammonite, etc. These evidences indicate the rising sea level rose relatively in the sedimentation period of Nabiao Fm. and a deepwater shelf environment, which was favorable for the preservation of organic matters. The V/(V+Ni), V/Cr and Ni/Co in Luofu Fm. and Tangting Fm. are 0.38–0.65, 0.73–4.10 and 3.70–6.72 respectively, indicating that the sea level dropped relatively in their sedimentation period, during which the water bodies became shallow, and the sedimentary environment was a weak oxidizing shallow water shelf environment. In addition, the variation of TOC has a high correlation with the enrichment degree of Ba element, indicating the favorable conditions for the enrichment and preservation of organic matters under an oxygen-deficient environment. Moreover, according to the identification of trace element indexes, the northwest of Guizhong Depression experienced the sedimentary cycle of relative rise to relative fall of sea level from bottom to top in the Middle Devonian sedimentation period. The relative sea level rose to the highest in the sedimentation period of Nabiao Fm., in which the organic-rich shales with stable thickness and high organic content were deposited. Hence, the Nabiao Fm. could be regarded as the favorable exploration target interval in this area.  相似文献   

帕米尔高原Rushan-Pshart古特提斯洋或中特提斯洋争论的岩石地球化学证据     

徐天德  王世锋  汤文坤  姚鑫 《地质科学》2020,(1):218-233

帕米尔高原上广泛分布的加里东期火山岩,印支期火山岩与燕山期火山岩被认为是块体依次向北俯冲拼贴到欧亚板块上的产物。特别是燕山期火山岩被认为是Rushan-Pshart中特提斯洋闭合的产物。但近年来地层古生物、火山岩证据不断表明Rushan-Pshart洋闭合时间在晚三叠一早侏罗世,由此限定Rushan-Pshart古特提斯洋性质,而帕米尔高原上广泛分布的燕山期火山岩是更南部的Shyok中特提斯洋闭合的产物。目前,中国境内Rushan-Pshart缝合带属性的研究工作展开较晚,研究程度较低。我们对塔什库尔干明铁盖沟一线燕山期火山岩带展开的工作发现零星分布的印支期花岗岩。印支期花岗岩错石U・Pb年龄显示岩体侵位时间在201 Ma左右。全岩主量元素特征表明岩石为I型高钾钙碱性闪长花岗岩;稀土元素在球粒陨石标准化图解中呈轻稀土元素相对富集,重稀土元素相对亏损的右倾海鸥型。明铁盖岩体的微量元素显示大离子亲石元素明显富集,而高场强元素明显亏损。稀土微量元素特征倾向花岗岩属性为岛弧型花岗岩,Sr-Nd-Hf同位素比值特征显示岩体形成于下地壳部分熔融环境。岩体的地化特征表明岩体形成的构造环境为板块汇聚的洋壳俯冲阶段,结合区域地质特征,我们将花岗岩体归为Rushan-Pshart古特提斯洋壳俯冲消减的产物。Rushan-Pshart缝合带传统上认为是中特提斯带,近年的研究进展认为其为古特提斯缝合带,本文的工作支持这种观点。Rushan-Pshart古特提斯缝合带的确立对帕米尔高原与青藏高原主体的块体对比提供了可信的对比方案,并对青藏高原新生代陆内变形方式的争论提供了可靠的证据。  相似文献   

滇西北剑川盆地新近系地层时代的新认识及构造意义     

王书兵  蒋复初  田国强  傅建利  李朝柱 《第四纪研究》2020,(1):28-39

地处板块接触地带的滇西北剑川地区是研究新构造运动的重要场所。剑川盆地保留有较为完整的新生代地层,在1:250000地质图上,新生界自下而上为古新统勐野井组、始新统宝相寺组、渐新统金丝厂组、中新统双河组和上新统剑川组;其中双河组为一套含可采煤层的砂泥岩夹泥灰岩沉积,剑川组为一套火山-沉积岩组。近期的研究揭示双河组和剑川组均属始新世,但发表的年龄相互包含,并没有清楚的把两者分开。本文采用Ar-Ar和锆石U-Pb方法测试了双河组和剑川组顶、底凝灰岩的年龄,辅以岩体、岩脉的年龄,重新厘定了两个组的顶、底年龄。剑川组顶部凝灰岩锆石SHRIMP U-Pb年龄为34 Ma±;底部凝灰岩黑云母Ar-Ar坪年龄为36 Ma±,与底部侵入岩脉的锆石SHRIMP U-Pb年龄一致;中上部侵入岩脉的黑云母Ar-Ar坪年龄在34~36 Ma之间。同时,老君山岩体、玉召块岩体和沙帽山岩体的锆石SHRIMP U-Pb年龄在34~35 Ma之间。剑川火山-沉积岩组的年龄集中在34~36 Ma之间,属始新世晚期。剑川双河煤矿矿部至三家村及五家村一带,双河组之下新发现一套凝灰岩,其黑云母Ar-Ar坪年龄和锆石SHRIMP U-Pb年龄均为37 Ma±,表明双河组的起始年代不超过37 Ma;双河组形成于36~37 Ma之间,也属始新世晚期。新的结果表明剑川盆地始新统地层应包括宝相寺组、金丝厂组、双河组和剑川组,缺失渐新统沉积。结合其他盆地的年龄数据,表明剑川乃至整个云南地区在渐新世期间为褶皱隆起期。  相似文献   

南京下蜀土的地球化学特征及其物源指示意义     

綦琳  乔彦松  王燕  彭莎莎  杨帅斌  白文彬 《第四纪研究》2020,(1):190-202

风尘堆积的物源研究对于揭示物源区的环境演化状况、重建古风场强度和古大气环流格局等都具有重要的意义。目前长江下游地区下蜀土的物质来源问题仍然存在争议。为了解决这一争议问题,本文以南京泰山新村下蜀土剖面为研究对象,开展了系统的地球化学研究。通过对南京下蜀土的常量元素、微量元素、Nd同位素进行测试,并与黄土高原同期黄土进行对比分析,探讨其对长江下游下蜀土的物源指示意义。南京下蜀土与北方黄土具有相似的常、微量元素UCC标准化曲线和稀土元素球粒陨石标准化曲线,但是它的Zr、Hf含量较高,Tl、Pb含量较低,且具有较高的SiO2/Al2O3、TiO2/Al2O3、Nb/Ta和GdN/YbN,较低的SiO2/TiO2、Zr/Hf、Y/Ho、Lu/Hf和εNd(0)值,说明南京下蜀土的物质来源明显有别于黄土高原黄土。南京下蜀土与长江中游下蜀土在地球化学特征方面有较多的相似性,指示其物质来源与中游下蜀土的物质来源相似,主要来源于长江中下游地区的松散沉积物。  相似文献   

花岗岩残积土动态冲击性能的SHPB试验研究     

刘新宇  张先伟  岳好真  孔令伟  徐超 《岩土力学》2020,41(6):2001-2008

为研究花岗岩残积土的动态冲击性能，开展了高速冲击下的分离式霍普金森压杆（SHPB）试验，与常规应变率下的试验结果比较，分析了高应变率对花岗岩残积土的应力?应变特性和强度的影响。结果表明：低、高应变率下的花岗岩残积土的?-?a（轴向应力?轴向应变）曲线均呈现出软化型。随着应变率 增加，?-?a曲线向?a增大的方向移动，破坏应变?af增加。但高应变率下?af增加的程度更加明显。花岗岩残积土的峰值强度普遍具有应变率依赖性，二者可用直线关系拟合，但低、高应变率下的拟合关系并不一致。提出了率敏性因子m定量评价依赖性强弱。研究发现，随着应变率的提高，强度的应变率依赖性减弱，低应变率下的m为26.694，而高应变率下仅为0.013。相关试验结果指出，高速冲击荷载对土体总体有害。工程中应该采取合理措施控制冲击荷载的危害。该研究有助于深化花岗岩残积土动态冲击性能的理解，为相关工程的施工与设计提供技术参考。  相似文献   

基于级配方程的粗粒料压实特性试验研究     

吴二鲁  朱俊高  郭万里  陆阳洋 《岩土力学》2020,41(1):214-220

级配显著影响着堆石料的压实特性，定量表述级配对堆石料压实特性的影响至关重要。基于连续级配土的级配方程，设计了16组不同级配的试验粗粒料，进行了表面振动压实试验和侧限压缩试验，定量研究了级配对粗粒料压实特性的影响。研究表明：由表面振动压实（动应力）试验和侧限压缩（静应力）试验得到的干密度与级配曲线面积之间均呈二次函数关系，且干密度中的最大值对应的级配曲线面积均在0.9附近；无论是表面振动压实试验还是侧限压缩试验，堆石料都存在干密度最优（最大）的级配。依据试验成果，给出了所试验堆石料的最优级配区间（级配上、下包络线）；同时，利用相似级配法论证了实际级配粗粒料的最优级配区间，并根据国内外多座土石坝粗粒料的设计级配验证了该最优级配区间的普遍适用性，为土石坝粗粒料的级配设计提供了理论依据。  相似文献   

Nature and Evolution of Pre-Neoproterozoic Continental Crust in South China: A Review and Tectonic Implications     

WANG Kai  DONG Shuwen  YAO Weihu  ZHAO Tianyu 《《地质学报》英文版》2020,94(6):1731-1756

South China as an amalgamation of the Yangtze and Cathaysia blocks is composed of Archean to Mesoproterozoic basement overlain by Neoproterozoic and younger cover. Both the constituent Yangtze and Cathaysia blocks contain well-preserved Neoproterozoic rocks that have been extensively studied in terms of the age and tectonic nature, but less is known about their earlier crustal history due to the incomplete rock record. Recent efforts in investigating the yet survived crustal nature based on isotopic and elemental signatures preserved in igneous and sedimentary rocks have steadily improved our knowledge about the pre-Neoproterozoic continental crustal evolution in South China. In this paper, we summarize the up-to-date pre-Neoproterozoic records, including petrological, geochronological, geochemical and geophysical data, across South China, and discuss its spatiotemporal patterns of the pre-Neoproterozoic crust and the relevant tectonic events. While the xenocrystic/inherited and detrital zircon records suggest widespread Archean (mainly ca. 2.5 Ga) crustal components within both the Yangtze and Cathaysia blocks, exposed Archean rocks are only limited to isolated crustal provinces in the Yangtze Block. These Archean rocks are dominated by TTGs (tonalite-trondhjemite-granodiorite) with varied ages (3.3–2.5 Ga) and zircon Hf isotopes, indicating a compositionally heterogeneous nature of the Archean Yangtze Block and, by inference, the development of multiple ancient terranes. The early Paleoproterozoic (2.4–2.2 Ga) tectonomagmatic events characterize the western Yangtze Block and are supportive of an east-west subdivision of the Yangtze basement, whereas the late Paleoproterozoic (2.1–1.7 Ga) orogeneses may have affected a larger area covering both the western and eastern parts of the Yangtze Block, and also the Cathaysia Block. The eastern Yangtze Block with generally northeastward-younging late Paleoproterozoic magmatism and metamorphism likely experienced a prolonged 2.05–1.75 Ga orogenic process welding the various Archean proto-continents, consistent with the documentation of a buried late Paleoproterozoic orogenic belt imaged by deep seismic profiling from its central part and of a slightly older ophiolitic mélange in the northern part. The Cathaysia Block was probably involved in a short-lived 1.9–1.8 Ga orogenic event. The two orogeneses overlapped in time and may have contributed to the cratonization of a possible unified South China, and are referred to be linked with the assembly of the Nuna Supercontinent. The subsequent late Paleoproterozoic to early Mesoproterozoic rift successions and intrusions (1.7–1.5 Ga) in the southwestern Yangtze Block, and the ca. 1.43 Ga rifting in Hainan Island of the Cathaysia Block could be responses to the Nuna break-up. Late Mesoproterozoic (1.2–1.0 Ga) magmatism of varied age and nature in different localities of the Yangtze Block is reflective of a complex tectonic process in the context of the assembly of the Rodinia Supercontinent. Similar-aged metamorphism (1.3–1.0 Ga) is recorded in Hainan Island, reflecting the Grenvillian continental collision during the Rodinia assembly, but further studies are necessary to better constrain the late Mesoproterozoic tectonic framework of South China.  相似文献