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91.
川西北微细浸染型金矿集中区构造对金成矿的控制   总被引:2,自引:0,他引:2  
王全伟  梁斌 《矿物岩石》2004,24(4):49-52
川西北微细浸染型金矿集中区,金成矿带及金矿床明显受构造的控制。从区域成矿地质背景及控矿因素来看,大地构造环境制约着“矿源层”及赋矿地层的形成,区域断裂构造控制着金成矿带及金矿床的空间分布。川西北地区金矿矿田构造规律的研究表明,金矿化局部富集主要发生在断裂产状变化部位、两组断裂的交汇部位以及碎裂岩与构造透镜的接合部位。  相似文献   
92.
在综合分析太平煤矿井水文地质条件、出水点岩性特征的基础上,通过钻孔探放、水样化验资料的对比分析,认为该矿+700水平胶带暗斜井的间接充水水源可能来自摩梭河;基于涌水点位置与出水量,以及瞬变电磁法确定的巷道前方富水区域情况,确定了采用浅层注浆法封堵的治水方案。  相似文献   
93.
Based on abundant aftershock sequence data of the Wenchuan MS8.0 earthquake on May 12, 2008, we studied the spatio-temporal variation process and segmentation rupture characteristic.Dense aftershocks distribute along Longmenshan central fault zone of NE direction and form a narrow strip with the length of 325 km and the depth between several and 40 km.The depth profile(section of NW direction) vertical to the strike of aftershock zone(NE direction) shows anisomer-ous wedgy distribution characteristic of aft...  相似文献   
94.
The seismicity of Longmenshan fault zone and its vicinities before the 12 May 2008 Wenchuan MS8.0 earthquake is studied.Based on the digital seismic waveform data observed from regional seismic networks and mobile stations, the focal mechanism solutions are determined.Our analysis results show that the seismicities of Longmenshan fault zone before the 12 May 2008 Wenchuan earthquake were in stable state.No obvious phenomena of seismic activity intensifying appeared.According to focal mechanism solutions of ...  相似文献   
95.
Miocene marl is the most widespread Tertiary stratigraphic record in the northern Tibet Plateau, termed the Wudaoliang Group in the Hoh Xil region and the correlative Suonahu Formation in the Qiangtang region. The uniform marl overlies red beds of the Eocene-Oligocene Fenghuoshan Group. The Wudaoliang Group is generally 100-400 m thick, but the thickest strata are 700-1300 m, located in the Haidinghu (Maiding Lake) and Tuotuohe (Tuotuo River) regions respectively. Based on observations from eight measured sections and outcrops, the thin-bedded marl, which varies in colour from grey-white to light brown-grey, is explained as a large-scale or serial lacustrine deposit stretching throughout northern Tibet.The Wudaoliang Group commonly crops out on geographic lowland at an average elevation of 4600 m above sea level within the mountain chains, showing concordant summit levels, e.g. the Fenghuoshan and Bairizhajia Mountains. These mountains with a flat ridge are considered to be remains of the palaeo-planati  相似文献   
96.
The paper describes an early and primitive sauropod dinosaur, Gongxianosaurus shibeiensis (gen. et sp. nov.), from the Dongyuemiao Member of the Lower Jurassic Ziliujing Formation in Shibei Township, Gongxian County, Sichuan Province, China, which is one of the 5 dinosaur fossils discovered in Gongxian in 1997. Except the skull which is incomplete, the fossils are well preserved. It has some features of both sauropods and prosauropods. It is an intermediate type in the evolution of dinosaurs from prosauropods to sauropods and provides materials for the study of the origin and evolution of the sauropod dinosaur fauna. The discovery of this new sauropod furnishes a way for the stratigraphic correlation between the Early Jurassic Ziliujing Formation in the Sichuan basin and the Lower Jurassic Lufeng Formation in the Central Yunnan basin.  相似文献   
97.
Tetrahedrite-Group Minerals in the Jinjitai Gold Deposit,Western Sichuan   总被引:1,自引:0,他引:1  
There are quite a few tetrahedrite-group minerals in the Jinjitai gold deposit, western Sichuan, which occur in an interstratified fractured zone of Middle Devonian carbonate rock series. The gold ore consists of pyrite, chalcopyrite, tetrahedrite-group minerals, galena, sphalerite and gold-silver series minerals, with an element association of Au-Cu-Ag-Pb-As-Sb-Bi. Electron microprobe analyses of the tetrahedrite-group minerals gave the following results: copper 40.04 to 42.27% (average 40.04%), iron 1.24 to 7.78% (average 4.13%), zinc 0.39 to 7.06% (average 3.58%), arsenic 5.41 to 17.40% (average 8.84%), antimony 2.70 to 20.46% (average 15.87%), and silver 0.02 to 0.73% (average 0.28%). The mineral varieties include zinc-antimony-tetrahedrite, iron-antimony-tetrahedrite, iron-tennatite and zincotennatite. These data show that there is a complete isomorphous series between Sb and As. From above downwards tetrahedrite varies from zinc- and antimony-rich to iron- and arsenic-rich compositions. Their occu  相似文献   
98.
早泥盆世-中泥盆世早期的右江盆地处于被动陆缘裂陷盆地阶段.本文通过对这一时期右江盆地的沉积层序、构造演化、古气候以及全球海平面等因素的综合分析,建立了右江被动陆缘裂陷盆地的层序充填动力学模型.该模型充分体现了构造控盆、盆控相,不同相带的时空配置形成层序的不同样式的基本思想,强调了构造沉降和全球海平面升降共同作用下的相对海平面变化所引起的可容纳空间的变化与沉积物供应比值的关系对层序样式的决定作用.通过代表台缘相的横县六景剖面的验证,该模型清楚地反映了全球海平面变化对超层序的主要控制作用,区域构造沉降的叠加效应使相对海平面曲线的R拐点要早于全球海平面曲线的R拐点,而F拐点要晚于全球海平面曲线的F拐点.古气候因素体现在层序充填物(气候敏感沉积物的种类、生物种属的差别)的差异性上.本文所建立层序充填动力学模型的思路和方法对于其他地区、其他类型盆地类似的研究具有借鉴意义,由此建立的被动陆缘裂陷盆地的层序充填动力学模型对于了解右江盆地的构造动力学与特提斯构造域的关系、促进盆地动力学理论的发展和该区的资源勘探具有重要的理论意义.  相似文献   
99.
川南古叙矿区某矿在基建过程中多次揭露大型导水陷落柱或溶洞,导致突水事故。该矿煤系地层底板为茅口组灰岩,岩溶发育,富水性强,为煤层的直接充水含水层。依据地表水和地下水的水质特征,结合连通试验,分析了矿区地表水和地下水的补给关系,并讨论了地下水水质的成因及其对茅口组灰岩岩溶发育的影响。结果表明,地表水水质为含可溶性固体少的HCO3-Ca型水,呈中性—弱碱性;地下水水质以含可溶性固体少的SO4·HCO3-Ca型水为主,呈酸性—中性,次为含可溶性固体少的SO4-Ca型水。地表水与地下水相互补给,呈酸性的地下水水质源于硫铁矿层的溶解和氧化,对茅口组灰岩岩溶发育有强烈的促进作用。此结果对防治矿井水害具有一定的指导意义。  相似文献   
100.
Lying at the junction of the Dabashan,Longmenshan and Qinling mountains,the Micangshan Orogenic Belt coupled with a basin is a duplex structure and back-thrust triangular belt with little horizontal displacement,small thrust faults and continuous sedimentary cover.On the basis of 3D seismic data,and through sedimentary and structural research,the Micangshan foreland can be divided into five subbelts,which from north to south are:basement thrust,frontal thrust,foreland depression-back-thrust triangle,fore...  相似文献   
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