Upper Paleozoic Marine Shale Characteristics and Exploration Prospects in the Northwestern Guizhong Depression,South China   总被引：1，自引：0，他引：1  

Zhenhong Zhu  Genshun Yao  Zhanghua Lou  Aimin Jin  Rong Zhu  Chong Jin  Chao Chen 《中国海洋大学学报(英文版)》2018,17(4):773-790

Multiple sets of organic-rich shales developed in the Upper Paleozoic of the northwestern Guizhong Depression in South China. However, the exploration of these shales is presently at a relatively immature stage. The Upper Paleozoic shales in the northwestern Guizhong Depression, including the Middle Devonian Luofu shale, the Nabiao shale, and the Lower Carboniferous Yanguan shale, were investigated in this study. Mineral composition analysis, organic matter analysis(including total organic carbon(TOC) content, maceral of kerogen and the vitrinite reflection(Ro)), pore characteristic analysis(including porosity and permeability, pore type identification by SEM, and pore size distribution by nitrogen sorption), methane isothermal sorption test were conducted, and the distribution and thickness of the shales were determined, Then the characteristics of the two target shales were illustrated and compared. The results show that the Upper Paleozoic shales have favorable organic matter conditions(mainly moderate to high TOC content, type Ⅰ and Ⅱ_1 kerogen and high to over maturity), good fracability potential(brittleness index(BI) 40%), multiple pore types, stable distribution and effective thickness, and good methane sorption capacity. Therefore, the Upper Paleozoic shales in the northern Guizhong Depression have good shale gas potential and exploration prospects. Moreover, the average TOC content, average BI, thickness of the organic-rich shale(TOC 2.0 wt%) and the shale gas resources of the Middle Devonian shales are better than those of the Lower Carboniferous shale. The Middle Devonian shales have better shale gas potential and exploration prospects than the Lower Carboniferous shales.  相似文献   

鄂尔多斯伊克昭盟晚古生代沉积环境与岩相古地理   总被引：14，自引：5，他引：9       下载免费PDF全文

王张华  张国栋 《古地理学报》1999,1(3):28-39

依据露头、岩心、测井及地震等资料并运用层序地层学分析及基准面旋回分析等手段,对本区地层进行了小层划分与对比,首次将地层划分到岩性段。在此基础上,将研究区置于构造及其控制的海侵[CD*1/2]海退旋回背景下,运用比较沉积学理论,总结出本区晚古生代发育有潮坪、扇三角洲、浅水三角洲、冲积扇、辫状河和曲流河6种沉积体系及一系列亚微相;提出9种构成储集砂体的重要成因类型,并阐述了其形成条件、发育特征和识别标志。对不同时期岩相古地理研究表明,本区处于伊克昭盟隆起南坡,在北高南低及西陡东缓的古地形控制下,北或北北东向水系继承性发育,西部以形成扇三角洲（太原组）和冲积扇（山西组-上石盒子组）沉积为主,而东部则以形成浅水三角洲（太原组）、辫状河（下石盒子组）、曲流河（山西组、上石盒子组）沉积为主。  相似文献   

基于区域优势理论的中国水资源利用现状分析     

刘德地  陈晓宏  李梅  楼章华 《地球科学进展》2009,24(11)

为了揭示不同区域水资源利用变化之间的空间关系,借鉴经济学中的区域优势理论,对中国水资源2001-2006年间水资源利用的区域优势及其演化机制进行了分析.研究结果表明:①山东、河南、四川、海南和河北五省农业用水优势处于前5位,并呈增加趋势,使得这些省份的农业用水优势得到加强;非农业用水优势明显增加的为北京、山东、山西、内蒙古、浙江,其增幅均在0.2以上,而非农业用水优势下降趋势最为明显的是天津和辽宁,其下降幅度均在0.4以上.②中国水资源利用的区域优势在其演化过程中主要存在经济、社会、自然等3种驱动因素,它们在全国范围内主导着水资源利用区域优势的演化,同时也主导水资源利用结构的演进.  相似文献   

塔河油田奥陶系碳酸盐岩缝洞储层油气成藏动力学与油田水体类型   总被引：1，自引：0，他引：1  

楼章华  朱蓉  云露  尚长健 《海相油气地质》2009,14(3):60-64

塔河油田是大型的碳酸盐岩不整合—古岩溶缝洞型奥陶系油气藏。由塔河油田主体往南,油气驱替程度逐渐降低,缝洞系统中含水量逐渐增加。油水界面分布总体上由潜山顶部向周围斜坡波动中降低。塔河油田的区域构造背景、储层缝洞系统以及成藏动力学过程导致了流体分布的非均质性。根据储层孔隙结构特征、油气驱替过程、开发过程中产出水的化学—动力学响应,塔河奥陶系缝洞油藏的水体类型可以区分出三种:洞穴底部油气驱替残留水、洞穴周缘小缝洞系统驱替残留水、储层下部层间水。不同水体类型的出水时间、水体能量、含水率、水化学性质等会呈现出不同的变化规律。  相似文献   

Climate implications of major geochemical elements in the Holocene sediments of the North and East China monsoonal regions     

Qianli Sun  Zhanghua Wang  Jing Chen  Wu Feng 《Frontiers of Earth Science》2009,3(3):291-296

Two Holocene sediment cores were retrieved respectively from the enclosed Lake Daihai in the monsoon/arid transition zone of North China and the Taihu Lake coast in the monsoonal area of the Yangtze delta, Eastern China. Distribution of major geochemical elements and their ratios were employed to reveal the characteristics of Holocene climate and associated environmental implications in the two regions. It is suggested that the temporal distribution of major elements serve as a useful indicator to denote the variations of monsoon effective precipitation for the enclosed lake area. High values of resistant elements such as Al₂O₃, SiO₂, TiO₂, (FeO + Fe₂O₃), MnO in the lake sediments correspond to the depressed chemical weathering and weakened mon-soon effective precipitation, while the highs of mobile and easy soluble elements such as MgO, CaO, Na₂O reflect the enhanced chemical weathering and increased monsoon effective precipitation in the lake basin. In comparison, the behaviors of the major elements in sediments of the Taihu Lake coast were largely controlled by the changes both in sea transgression in the different Holocene time periods and the monsoon precipitation. The relatively highs of Al₂O₃, TiO₂, (FeO + Fe₂O₃), in marine-influenced sediments suggest relatively strong coastal hydrodynamics and chemical weathering, and vice versa. Meanwhile, the lows of SiO₂, Na₂O and CaO in the non-marine-influenced sediments also denote relatively strong hydrodynamics and chemical weathering due to enhanced monsoon precipitation, and vice versa. Sedimentary environment should be taken into account when achieving a full understanding of their climate implications.  相似文献   

Changes in summer monsoon precipitation over Hunan Province during 1952–2007: response to the west Pacific sea surface temperature and global warming     

Jingjing Tang  Hao Xu  Zhanghua Wang 《Frontiers of Earth Science》2009,3(4):411-418

Using a historical database (1952–2007) of sea surface temperature (SST) from a subtropical high-controlled area (110°E–140°E, 15°N–35°N) of the west Pacific Ocean and the precipitation over Hunan Province of southeast China, we analyzed time series variations of precipitation in relation to the East Asian summer monsoon and a global warming setting. The results show that there has been a significant increase in SST of the subtropical high-controlled area in the recent 50 years. Although the increase in annual summer monsoon precipitation during the same period has been subtle over Hunan province, seasonal rainfall distribution has obviously changed, represented by a reduction in May, but a significant increase through June to August, especially in July. We suggest that the mechanism of seasonal redistribution of monsoon precipitation is primarily due to the increasing SST that delays the intrusion of the west Pacific Subtropical High, therefore leading to a postponing of migration of the East Asian summer monsoon rainfall belt inland and northward.  相似文献   

Lithological and palynological evidence of late Quaternary depositional environments in the subaqueous Yangtze delta, China   总被引：2，自引：0，他引：2  

Zhanghua Wang  Hao Xu  Qing Zhan  Yoshiki Saito  Zhongfa He  Jianlei Xie  Xiao Li  Yonghong Dong 《Quaternary Research》2010,73(3):550-562

AMS ¹⁴C ages of post-glacial core sediments from the subaqueous Yangtze delta, along with sedimentary structures and distributions of grain size, pollen spores, and dinoflagellate cysts, show an estuarine depositional system from 13 to 8.4 cal ka BP and a deltaic system from 5.9 cal ka BP to the present. The estuarine system consists of intertidal to subtidal flat, estuarine, and estuarine-front facies, characterized by sand–mud couplets and a high sedimentation rate. The deltaic system includes nearshore shelf and prodelta mud featured by lower sedimentation rate, markedly fewer coastal wetland herbaceous pollens, and more dinoflagellate cysts. We explain the extremely high sedimentation rate during 9.2–8.4 cal ka BP at the study site as a result of rapid sea-level rise, high sediment load due to the unstable monsoonal climate, and subaqueous decrease of elevation from inner to outer estuary. A depositional hiatus occurred during 8.2–5.9 cal ka BP, the transition from estuarine to deltaic system, caused possibly by a shortage of sediment supply resulting from delta initiation in paleo-incised Yangtze valley and strong tidal or storm-related reworking in offshore areas. The subsequent development of deltaic system at the study site indicates accelerated progradation of Yangtze delta post-5.9 cal ka BP.  相似文献   

长江三角洲南部平原晚新生代特征孢粉分布及其对沉积地貌演变的意义          下载免费PDF全文

周园军  王张华  李晓  谢建磊  何中发  赵宝成 《古地理学报》2011,13(3):287-297

在对长江三角洲南部平原5个钻遇基岩的晚新生代钻孔的地层、岩性、粒度分析的基础上,根据各岩心剖面中湿生、水生植物花粉和外来植物桫椤孢子化石的分布特征,阐述该区新近纪晚期以来沉积地貌环境演变过程,从而为长江演化的研究提供新的思路.结果显示,新近纪沉积物为粗细混杂的洪积扇相,缺乏湿生、水生植物花粉,反映了此时研究区古地势东西...  相似文献   

Compositional variations of olivine from the Jinchuan Ni–Cu sulfide deposit,western China: implications for ore genesis     

Chusi?LiEmail author  Zhanghua?Xu  Sybrand?A.?de?Waal  Edward?M.?Ripley  Wolfgang?D.?Maier 《Mineralium Deposita》2004,39(2):159-172

The Jinchuan Ni–Cu sulfide deposit is hosted by an elongated, olivine-rich ultramafic body that is divided by subvertical strike-slip faults into three segments (central, eastern, and western). The central segment is characterized by concentric enrichments of cumulus olivine crystals and interstitial sulfides (pyrrhotite–pentlandite–chalcopyrite intergrowth), whereas the eastern and western segments are characterized by an increase of sulfides toward the lower contacts. In all segments sulfides are concentrated at the expense of intercumulus silicates. Olivine re-crystallization is found to be associated with actinolite alteration in some samples. The compositional variations of primary olivine from the sulfide-poor samples can be explained by a small degree of olivine crystallization (<5%) from a basaltic magma followed by local re-equilibration of the olivine with up to 30% trapped silicate liquid. In the sulfide-bearing samples the compositions of primary olivine record the results of olivine-sulfide Fe–Ni exchange that occurred after the trapped silicate liquid crystallized. Our olivine data indicate that Ni in the original sulfide liquids increased inward in the central segment and laterally away from the lower contact in the eastern segment. Variations in the compositions of sulfide liquids are thought to result from fractional segregation of immiscible sulfide liquid from a basaltic magma in a staging chamber instead of in situ differentiation. High concentrations of olivine crystals (mostly >50 modal%) and sulfide (averaging ~5 wt%) in the rocks are consistent with the interpretation that the Jinchuan deposit was formed by olivine- and sulfide-laden magma successively ascending through a conduit to a higher, now-eroded, level. Sulfide enrichment toward the center in the central segment and toward the lower contact in the eastern and western segments may have, in part, resulted from flow differentiation and gravitational settling during magma ascent, respectively.Editorial handling: P. Lightfoot  相似文献   

Sediment rating parameters and their implications: Yangtze River, China   总被引：4，自引：0，他引：4  

Guifang Yang  Zhongyuan Chen  Fengling Yu  Zhanghua Wang  Yiwen Zhao  Zhangqiao Wang 《Geomorphology》2007,85(3-4):166

This study examines the characteristics of sediment rating parameters recorded at various gauging stations in the Yangtze Basin in relation to their controls. Our findings indicate that the parameters are associated with river channel morphology of the selected reaches. High b-values (> 1.600) and low log(a) values (< − 4.000) occur in the upper course of the steep rock-confined river, characterizing high unit stream power flows. Low b-values (< 0.900) and high log(a) values (> − 1.000) occur in the middle and lower Yangtze River associated with meandering reaches over low gradients, and can be taken to imply aggradation in these reaches with low stream power. Higher b-values (0.900–1.600) and lower log(a)-values (− 4.000 to − 1.000) characterize the reaches between Yichang and Xinchang, immediately below the Three Gorges. These values indicate channel erosion and bed instability that result from changes in channel gradient from the upstream steep valley to downstream low slope flood plain settings. Differences in channel morphology accompany these changes. Confined, V-shaped valleys occur upstream and are replaced downstream by broad U-shaped channels. The middle and lower Yangtze shows an apparent increase in channel instability over the past 40 years. This inference is based on sediment rating parameters from various gauging stations that record increasing b-values against decreasing log(a)-values over that time. Analysis of the sediment load data also reveals a strong correlation between changes in sediment rating curve parameters and reduction of annual sediment budget (4.70 × 10⁸ t to 3.50 × 10⁸ t/year, from the 1950s to 1990s), largely due to the damming of the Yangtze and sediment load depletion through siltation in the Dongting Lake. Short-term deviations from the general trends in the sediment rating parameters are related to hydroclimatic events. Extreme low b-values and high log(a)-values signify the major flood years, while the reverse indicates drought events. When compared with rivers from other climate settings, it is evident that the wide range of values of the Yangtze rating parameters reflects the huge discharge driven by the monsoon precipitation regime of eastern China.  相似文献