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991.
东昆仑祁漫塔格地区位于东昆仑F e-Pb-Zn-Cu-Co-A u-W-Sn-多金属-盐类成矿带中,随着地质勘查进程的不断深入,该区现已成为铁矿、钨锡矿、铜矿、铅锌矿等矿产的矿集区,其地质找矿潜力非常巨大。笔者从成矿地质条件、区域地球物理场、区域地球化学场等角度对鸭子泉—维宝地区的成矿规律进行了剖析,并结合白干湖钨锡矿、维宝铅锌矿等典型矿床的特征对区内的各主要成矿元素的成矿类型、成矿期次进行了较为系统的归纳,认为该区具有寻找岩浆热液型钨锡矿、层控型铅锌矿、矽卡岩型铁铜多金属矿等矿产的有利地质条件,并对以上各类型矿床的产出环境、成矿时代、沉积(变质)建造、岩浆建造、控矿构造等成矿地质条件进行了总结,建立了区域成矿模式。 相似文献
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994.
鄂尔多斯盆地东北部是煤炭、石油、天然气、砂岩型铀矿等有机矿产共存的代表性地区之一,煤系烃源岩作为原始物质,在多种能源矿产成藏(矿)过程中起着重要作用。从煤系层序地层格架及沉积体系分析入手,分析了鄂尔多斯盆地东北部侏罗纪煤系烃源岩的种类、岩性、聚积环境、发育程度、时空分布等。结果表明,煤系烃源岩随时间在纵向上的变化与盆地的演化阶段相一致,盆地相对稳定期,烃源岩发育程度最好,初始和退覆充填期次之;空间上总体分布为由北向南,自西向东,层数增多,厚度增大。该区广泛发育的煤系烃源岩为多种能源矿产形成奠定了物质基础,其时空分布对多种能源共存成藏格局具有初始控制作用。 相似文献
995.
淮南板集煤矿F512断层导水性分析及地面注浆加固 总被引:1,自引:0,他引:1
板集煤矿F512断层落差70m,存在着导通上覆新生界松散层水与下伏太原组岩溶水的威胁,同时,断层带的破碎岩体也将对巷道掘进和支护带来困难。该矿先后施工了3个水文地质钻孔进行抽水和压水试验,根据岩心鉴定成果和岩石RQD值,认为断层带的岩心较为破碎;依据抽水过程中的流量变化、水位降深值和水位恢复值等指标及压水试验中透水率分析,发现该断层的导水性较差,具有弱渗透性。参考相邻矿区的经验,决定对断层破碎岩体采用地面注浆方法进行加固。整个工种注入水泥浆1 600m3,破碎岩体得到了有效加固,巷道掘进顺利通过了F512断层。 相似文献
996.
刘庄煤矿东二采区121102工作面所开采的11-2煤层为非突出煤层,但在工作面回采期间,存在瓦斯突出的可能。为防止工作回风巷尤其是上隅角瓦斯超限,确保工作面的正常生产,同时兼顾瓦斯资源的抽采利用,施工了最大长度496m,钻孔直径133mm的瓦斯抽采孔。实际应用表明,该孔投入使用后,整个工作面回采过程中均未发生过瓦斯超限现象,说明利用大口径长距离钻孔取代巷道抽放瓦斯是完全可行的。本文介绍的高位钻场长钻孔的设计、施工和瓦斯抽采情况,可以为今后同类工作面中长钻孔的施工提供借鉴。 相似文献
997.
Since the late Quaternary Period, the rapid rising of the northeastern Qinghai-Tibetan Plateau has greatly changed the East
Asian climate and formed different regional monsoon climates. Various microstructures of the loess in northern China have
formed under a variety of climatic conditions. The scanning electron microscope (SEM) and energy spectrum analysis are used
in this paper to study the relationship between the indexes of loess microstructures and the forming climates, and the indexes
include the diameter of sand grains, Ca/Fe value and the characteristic shapes of the loess from SEM microstructures pictures.
In terms of their respective climatic circumstances, the major microstructures of regional loess may be classified into nine
categories according to their forms and particle sizes, such as loess formed in near-sand source, loess of granule sand dropping,
and loess formed in hot and rainy places, i.e. with the loess SEM pictures, climates of about 15 ka b.p. in different places may be evaluated. In conclusion, the clear and distinguishable loess microstructures and their indexes
in the Loess Plateau of China can also deduce the evolution of climate, such as warm or cold and wet or dry, and even sandstorm
activities when the loess is deposited. 相似文献
998.
Baohong Chen Kaiwen Zhou Kang Wang Jigang Wang Sumin Wang Xiuwu Sun Jinmin Chen Cai Lin Hui Lin 《海洋学报(英文版)》2022,41(1):1-2
This research investigated eight stations in Clarion-Clipperton Fracture Zone(CCFZ) in the eastern tropical Pacific in 2017 to study the spatial distribution characteristics of nutrients and chlorophyll a(Chl a) concentration,and compared nutrient concentrations and molar ratios with those of other investigations 20 years ago in the same area. The study found that dissolved inorganic nutrient(N, P and Si) concentrations were lowest in the upper layer, and increased from surface to some depths, t... 相似文献
999.
Shuo Chen Renhai Pu Huiqiong Li Hongjun Qu Tianyu Ji Siyu Su Yunwen Guan Hui Zhang 《海洋学报(英文版)》2022,41(9):86-106
The Dongfang1-1 gas field (DF1-1) in the Yinggehai Basin is currently the largest offshore self-developed gas field in China and is rich in oil and gas resources. The second member of the Pliocene Yinggehai Formation (YGHF) is the main gas-producing formation and is composed of various sedimentary types; however, a clear understanding of the sedimentary types and development patterns is lacking. Here, typical lithofacies, logging facies and seismic facies types and characteristics of the YGHF are identified based on high-precision 3D seismic data combined with drilling, logging, analysis and testing data. Based on 3D seismic interpretation and attribute analysis, the origin of high-amplitude reflections is clarified, and the main types and evolution characteristics of sedimentary facies are identified. Taking gas formation upper II (IIU) as an example, the plane distribution of the delta front and bottom current channel is determined; finally, a comprehensive sedimentary model of the YGHF second member is established. This second member is a shallowly buried “bright spot” gas reservoir with weak compaction. The velocity of sandstone is slightly lower than that of mudstone, and the reflection has medium amplitude when there is no gas. The velocity of sandstone decreases considerably after gas accumulation, resulting in an increase in the wave impedance difference and high-amplitude (bright spot) reflection between sandstone and mudstone; the range of high amplitudes is consistent with that of gas-bearing traps. The distribution of gas reservoirs is obviously controlled by dome-shaped diapir structural traps, and diapir faults are channels through which natural gas from underlying Miocene source rocks can enter traps. The study area is a delta front deposit developed on a shallow sea shelf. The lithologies of the reservoir are mainly composed of very fine sand and coarse silt, and a variety of sedimentary structural types reflect a shallow sea delta environment; upward thickening funnel type, strong toothed bell type and toothed funnel type logging facies are developed. In total, 4 stages of delta front sand bodies (corresponding to progradational reflection seismic facies) derived from the Red River and Blue River in Vietnam have developed in the second member of the YGHF; these sand bodies are dated to 1.5 Ma and correspond to four gas formations. During sedimentation, many bottom current channels (corresponding to channel fill seismic facies) formed, which interacted with the superposed progradational reflections. When the provenance supply was strong in the northwest, the area was dominated by a large set of delta front deposits. In the period of relative sea level rise, surface bottom currents parallel to the coastline were dominant, and undercutting erosion was obvious, forming multistage superimposed erosion troughs. Three large bottom current channels that developed in the late sedimentary period of gas formation IIU are the most typical. 相似文献
1000.
空心块体具有良好的阻水和促淤功能,近年来被广泛用于生态修复工程。本文结合水槽试验及Flow-3D数值模拟,分析了开敞型和半封闭型空心块体的阻水效应和泥沙淤积特性。结果表明:空心块体的开孔率对内部水流流速、紊动强度起主导作用,开孔率较小的半开敞型空心块体减速、制紊效果更强;开敞型和半封闭型空心块体近底层悬沙浓度分别增大56%和75%,两者均有利于促进泥沙在块体内部淤积,近底层水流紊动越强,泥沙淤积形态差异越大;空心块体所营造的低流速、泥沙微淤、内外连通的水沙环境是大型底栖生物的生境需求,半封闭型空心块体内部的低紊动水流结构更有利于大型底栖生物的栖息、繁衍。 相似文献