Application of NMR on Quantificational Characterization of Tight Glutenite Reservoirs Pore Size     

GUO Siqi  LU Shuangfang  XIAO Dianshi  ZHANG Luchuan  GU Meiwei 《《地质学报》英文版》2015,89(Z1):390-392

<正>Quantificational characterization of the microscopic pore structure is the key to evaluating tight reservoirs.Since tight reservoirs mainly develop nano-pores which are difficult to fully characterize pore throats’distribution by single conventional experimental method,there’s an urgent need to establish a characterization method by jointing several conventional experimental methods.The tight gas of Shahezi Formation in Xujiaweizi Fault  相似文献   

Present Situation of Core Mercury Injection Technology of Unconventional Oil and Gas Reservoir     

GU Meiwei  LU Shuangfang  XIAO Dianshi  GUO Siqi  ZHANG Luchuan 《《地质学报》英文版》2015,89(Z1):388-389

<正>Unconventional oil and gas step into a new area of global oil and gas exploration due to the success of the development of shale gas of America.Unconventional tight reservoir has huge differents with conventional reservoirs,including cell aggregation,migration patterns,source configuration storage,reservoir characteristics,flow mechanism and so on,which is  相似文献   

Compositions and Pressure–Temperature Conditions of Metamorphic Fluids Overprinting the Talate VMS Pb–Zn Deposit, Southern Altay, China     

ZHANG Hui  XU Jiuhu  CHENG Xihui  GUO Xuji  LIN Longhu  YANG Rui  BIAN Chunjing 《《地质学报》英文版》2015,89(3):794-810

The Talate Pb-Zn deposit,located in the east of the NW-SE extending Devonian Kelan volcanic-sedimentary basin of the southern Altaides,occurs in the metamorphic rock series of the upper second lithological section of the lower Devonian lower Kangbutiebao Formation(D_1k_1~2).The Pb-Zn orebodies are stratiform and overprinted by late sulfide—quartz veins.Two distinct mineralization periods were identified:a submarine volcanic sedimentary exhalation period and a metamorphic hydrothermal mineralization period.The metamorphic overprinting period can be further divided into two stages:an early stage characterized by bedding-parallel lentoid quartz veins developed in the chlorite schist and leptite of the ore-bearing horizon,and a late stage represented by pyritechalcopyrite-quartz veins crosscutting chlorite schist and leptite or the massive Pb-Zn ores.Fluid inclusions in the early metamorphic quartz veins are mainly CO_2-H_2O-NaCI and carbonic(CO_2±CH_4±N_2) inclusions with minor aqueous inclusions.The CO_2-H_2O-NaCl inclusions have homogenization temperatures of 294-368℃,T_(m,CO2) of-62.6 to-60.5℃,T_(h,CO2) of 7.7 to 29.6℃(homogenized into liquid),and salinities of 5.5-7.4 wt%NaCl eqv.The carbonic inclusions have T_(m,CO2)of-60.1 to-58.5℃,and T_(h,Co2) of-4.2 to 20.6℃.Fluid inclusions in late sulfide quartz veins are also dominated by CO_2-H_2O-NaCl and CO_2±CH_4 inclusions.The CO_2-H_2O-NaCl inclusions have T_(b,tot) of142 to 360℃,T_(m,CO2)of-66.0 to-56.6℃,T_(h,CO2) of-6.0 to 29.4℃(homogenized into liquid) and salinities of 2.4-16.5 wt%NaCl eqv.The carbonic inclusions have T_(m,Co2)of-61.5 to-57.3℃,and T_(h,CO2) of-27.0to 28.7℃.The aqueous inclusions(L-V) have T_(m,ice) of-9.8 to-1.3℃ and T_(h,tot) of 205 to 412℃.The P-T trapping conditions of CO_2-rich fluid inclusions(100-370 MPa,250-368℃) are comparable with the late- to post-regional metamorphism conditions.The CO_2-rich fluids,possibly derived from regional metamorphism,were involved in the reworking and metal enrichment of the primary ores.Based on these results,the Talate Pb-Zn deposit is classified as a VMS deposit modified by metamorphic fluids.The massive Pb-Zn ores with banded and breccia structures were developed in the early period of submarine volcanic sedimentary exhalation associated with an extensional subduction-related back-arc basin,and the quartz veins bearing polymetallic sulfides were formed in the late period of metamorphic hydrothermal superimposition related to the Permian-Triassic continental collision.  相似文献   

Exhumation History of the Xining Basin Since the Mesozoic and Its Tectonic Significance     

WANG Yannan  ZHANG Jin  QI Wenhu  GUO Shan 《《地质学报》英文版》2015,89(1):145-162

The Xining Basin is located in the northeastern Qinghai–Tibetan Plateau, and its continuous Cenozoic strata record the entire uplift and outgrowth history of the Tibetan Plateau during the Cenozoic. The newly obtained apatite fission track data presented here shows that the Xining Basin and two marginal mountain ranges have experienced multiphase rapid cooling since the Jurassic, as follows. In the Middle–Late Jurassic, the rapid exhumation of the former Xining Basin resulted from collision between the Qiangtang Block and the Tarim Block. During the Early–Late Cretaceous, the former Xining Basin underwent a tectonic event due to marginal compression, causing the angular unconformity between the Upper and Lower Cretaceous. In the Late Cretaceous to the Early Cenozoic, collision between the Qiangtang Block and the Lhasa Block may have resulted in the rapid exhumation of the Xining Basin and the Lajishan to the south. In the Early Cenozoic(ca. 50–30 Ma), collision between the Indian and Eurasia plates affected the region that corresponds to the present northeastern Qinghai–Tibetan Plateau. During this period, the central Qilian Block rotated clockwise by approximately 24° to form a wedge-shaped basin(i.e., the Xining Basin) opening to the west. During ca. 17–8 Ma, the entire northeastern Qinghai–Tibetan Plateau underwent dramatic deformation, and the Lajishan uplifted rapidly owing to the northward compression of the Guide Basin from the south. A marked change in subsidence occurred in the Xining Basin during this period, when the basin was tectonically inverted.  相似文献   

Geochemical Characteristics of Volcanic Rocks from ODP Site 794, Yamato Basin: Implications for Deep Mantle Processes of the Japan Sea   总被引：1，自引：0，他引：1  

CHEN Shuangshuang  LIU Jiaqi  GUO Zhengfu  CHEN Shengsheng  SUN Chunqing 《《地质学报》英文版》2015,89(4):1189-1212

Deep mantle processes and the dynamic mechanism of magmatism in the Japan Sea Basin are important processes that have not been studied in detail. In this paper, systematic evaluation of basalt samples from the ocean drilling program Site 794 in the Japan Sea was performed, which included petrography, whole-rock major- and trace-element analysis, Sr-Nd-Pb isotopic composition, and electron microprobe analysis of plagioclase and clinopyroxene. These basalts belong to the tholeiitic series with porphyritic texture and massive Ca-rich plagioclase, clinopyroxene, and minor olivine phenocrysts. The basalts are characterized as flat rare earth elements and high-field-strength elements with remarkably low ratios of(La/Yb)N(0.75–2.51), significant positive anomalies of Ba, Sr, and Rb and no Eu anomaly(δEu = 0.99–1.36). The samples showed relatively high 87Sr/86Sr(0.70425–0.70522), 207Pb/204Pb(15.511–15.610), and 208Pb/204Pb(38.064–38.557) values and a low 143Nd/144 Nd ratio(0.51271–0.51295). The basalts from Site 794 can be divided into upper, middle, and lower volcanic rocks(UVR, MVR, and LVR) on the basis of their stratigraphic level. The MVR was geochemically derived from the depleted mantle, whereas the UVR and LVR originated from a nondepleted and relatively enriched mantle source with contributions from subducted Pacific plate fluid and sediments. Use of geothermobarometers indicates that the crystallization pressure for the UVR and LVR(6.25–11.19 kbar) was significantly higher than that of the MVR(3.48–5.84 kbar). The UVR and LVR may have been derived from the low-degree(5%–10%) partial melting of spinel lherzolite, while the MVR originated from a shallower mantle source with a high degree(10%–20%) of partial melting. In addition, the geochemical characteristics of the samples are consistent with a younger age(13–17 Ma) and the depleted composition of the MVR and an older age(17–23 Ma) and slightly enriched composition of the UVR and LVR. Therefore, temporal changes in the mantle source from old and enriched to young and depleted and subsequently to old and nondepleted may have been associated with progressive lithospheric extension and thinning, as well as at least two episodes of diverse asthenospheric upwelling and pull-apart tectonic motion in the Yamato Basin.  相似文献   

Composition and Textual Characterization of Platinum-group Mineral (PGM) in Chromites from Zedang Ophiolite in Tibet, China     

GUO Guolin  YANG Jingsui  PAUL T. Robinson  XIONG Fahui  XU Xiangzhen  LIU Xiaodong  LIJinyang  LIU Zhao 《《地质学报》英文版》2015,89(Z2):16-17

<正>1 Introduction Platinum-group elements(PGE)are mainly concentrated in some specific minerals known as PGMs,which commonly occur in podiform chromites of ophiolites.In-situ PGM assemblages in chromites can provide valuable information on the physico-chemical nature of the parental melt(s)from which chromitite  相似文献   

煤系沉积岩应力–应变与应变–渗透率特征     

季小凯  郭建斌  邢同菊  谭希鹏 《煤田地质与勘探》2015,(3)

通过对济宁三号煤矿岩样进行现场采取和室内试验分析,探究对开采有威胁的3煤层顶板砂岩和红层的渗透率特征。试验结果表明,中粗砂岩的渗透率最大,泥岩样的渗透率相对较小;应力对岩石的渗透率有很大的影响,主要体现在节理的法向闭合和剪胀效应,其中应力剪胀能显著地改变岩石节理的渗透性;岩石应变渗透率曲线,表现出渗透率峰值"滞后"的特点;在岩石处于弹塑性阶段时候,渗透率的变化剧烈且具有不可预测性,然而岩石渗透率与体积应变有很好的一致性。通过对实验结果的归纳总结,本文将岩石在全应力应变过程中渗透率变化划分成5个阶段:微裂隙压密闭合阶段、微裂隙随机扩展阶段、裂隙扩展贯通阶段、裂隙错动充分发育阶段和裂隙二次闭合阶段。  相似文献   

河池市罗城县地下水环境质量评价及分析     

郭诗琪  班美玲 《地下水》2015,(1):75-78

为查清罗城县地下水情况,根据罗城县地下水监测数据和水质特点,选取高锰酸盐指数、硝酸盐氮、总硬度、氨氮、铁和锰作为评价因子,以GB/T14848-93《地下水质量标准》为评价标准,同时运用内梅罗指数法和模糊综合评价法对罗城县9个地下水监测点位(饮用水水源保护区、工业园区和矿山开采区)进行地下水环境质量评价。以模糊综合评价结果进行分析,饮用水水源保护区内地下水质良好,均达到Ⅱ类水质标准;工业园区有1个点位地下水水质超标,超标因子为总硬度;矿山开采区地下水质情况较差,有2个点位监测因子铁、锰超标,为Ⅴ类水。最后,针对罗城县地下水现状及存在的问题,提出合理的对策建议。  相似文献   

黄河上游某灌区地下水防污性能评价及预测     

郭康  冯加远 《地下水》2015,(3)

以黄河上游某灌区的地下水为研究对象,分别建立灌区潜水的DASLTCU模型和承压水DLCA模型对灌区地下水进行防污性能评价。选取潜水埋深(D)、含水层厚度(A)、地表土层厚度(S)、地表坡度(L)、地表岩性(T)、含水层渗透系数(C)、灌区现状图(U)作为灌区潜水的综合防污性能评价因子;选取承压水埋深(D)、隔水层岩性(L)、隔水层连续性(C)、隔水层厚度(A)作为灌区承压水的防污性能评价因子;应用ARCGIS和MODELFLOW对灌区地下水的综合防污性能进行评价和预测。得出现有灌溉规模下,潜水综合防污性差及较差地区占总面积24%,中等及以上地区占76%,灌区综合防污性总体较好。绘制出灌区潜水的现状防污性能分区图及30年后潜水的综合防污性能预测分区图。  相似文献   

巴丹吉林沙漠湖泊与高大沙山形成的若干问题探讨          下载免费PDF全文

丁宏伟  郭瑞  田刚  康亮  尹政 《甘肃地质》2015,24(2):9-17

依据前人研究成果和最新调查测试资料,深入探讨了巴丹吉林沙漠湖泊水的补给来源、补给模式及高大沙山的形成机理。认为沙漠湖泊水和地下水的补给来源不是当地降水和周边雅布赖山—北大山的降水形成的地表洪水,而是南部青藏高原(包括祁连山)现代大气降水、冰雪融水、高原湖水的远源补给。补给模式为:高原富含CO2气体和Ca CO3的入渗水,通过深大导水断裂通道形成的区域地下水流循环系统,源源不断地自南向北运移到沙漠地带。地下水在通过沙漠湖泊区弧形"叠瓦状"垂向导水构造断裂向上越流过程中被广泛分布的岩浆岩加热,沿断层溢出地表形成湖泊群,同时导致水中CO2的释放和Ca CO3的沉积,形成钙华、钙质根管和钙质胶结层。高大沙山的形成机理是:深层地下热水向上越流补给了沙漠覆盖区,在承压水头以下形成鼓丘状的沙漠地下水,承压水头以上,水蒸气继续向上运移并被凝结在沙粒表面,未被吸附凝结的热水蒸气继续向上运移并被吸附在新沉积的沙粒表面,形成湿砂层并接受更新的沙粒沉积。如此反复循环,则沙丘高度不断增加,逐步形成高大的固定沙山。  相似文献