一种简单的大地电磁阻抗张量畸变分解方法   总被引：7，自引：0，他引：7       下载免费PDF全文

王立凤  晋光文  孙洁  白登海 《地震工程学报》2001,23(2):172-180

提出了一种简单的大地电磁阻抗张量畸变分解方法，引入3d/2d模型，使得全畸变的大地电磁阻抗张量被生意人经，通过对比Swift旋转和Bahr分解后的资料，用联系二的畸变矩阵表示浅层三维电性异常体对区域二维构造的局部畸变影响，通过研究畸变张量矩阵，并对其进行分解，可将局部三维电性不均匀体产生的畸变与区域构造分离开来，从而了解区域构造的维数特征和局部畸变类型及其对区域构造的影响，最后，应用3个测点的实际资料，对这种简单的畸变分解方法进行了检验，结果表明，该方法简单且应用方便，解释效果较好。  相似文献   

桂西古岩溶型金矿地质特征   总被引：6，自引：0，他引：6       下载免费PDF全文

罗允义 《中国地质》2003,30(2):179-185

桂西地区自寒武纪至三叠纪发生了多次古侵蚀作用，已大致查明有11次沉积间断时期形成了古岩溶面，其中两次大范围的构造隆升及一次在裂谷拉张期相对持续时间较长的古水下岩溶作用，造成古生界为主的碳酸盐岩系溶蚀尤其强烈，形成大面积的古岩溶面。这些古岩溶面对微细粒浸染型金矿的控制非常明显，部分金矿床虽未直接产于古岩溶面，但其控矿断裂带多与深部古岩溶隐伏带有关系，古岩溶面起到间接控矿作用；主要金矿化的岩性有细碎屑岩、硅质岩、基性及中酸性侵入及喷出岩等，均为硅铝质岩系，而矿化最终底板均为古岩溶面下的碳酸盐岩系。金矿形成机制为：古岩溶潜山构造在后期叠加构造蚀变时，由地层淋滤出的金在古岩溶面及其影响带发生再富集而成矿。  相似文献   

阜新盆地王营矿气藏成因分析   总被引：7，自引：0，他引：7  

孟庆山 《中国煤田地质》2003,15(6):24-26

通过对王营矿气藏的气体组分分析和同位素分析,论述了气藏的气体主要来源于煤层气,有机组分为58.68%～78.68%,δ13C1≤-30‰,少部分来自于煤系地层的无机成因气和深层的无机成因气或者叫幔源气,无机组分在21.32%～41.32%之间,δ13C2在-13.6‰～-4.1‰之间,R/RA为2.48～2.63。盆缘的深大断裂和盆地基底的断裂及第四纪辉绿岩的侵入可能是幔源气的运移通道。  相似文献   

Petrologic and geochemical characteristics of “barkinite” from the Dahe mine, Guizhou Province, China     

Yuzhuang Sun 《International Journal of Coal Geology》2003,56(3-4):269-276

Although “barkinite” has long been studied by many geologists, its geochemical characteristics and environment of deposition are still not known in detail. In order to study the petrography and geochemical characteristics of “barkinite”, coal samples from two Permian coal seams were taken from the Dahe mine, Guizhou Province. The samples were separated into maceral fractions, and then analyzed by microscopical, isotopic, Rock-Eval, and geochemical methods. The microscopical results indicate that “barkinite” occurs as four main types. According to their relationship to other maceral groups, “barkinite” is ostensibly formed under variably dry–wet or oxidizing–reducing conditions. The extract yield, isotope data and Rock-Eval values of “barkinite” are different from other macerals. Microscopical and geochemical results indicate that “barkinite” forms part of the liptinite group.  相似文献   

神府矿区活鸡兔矿井烧变岩水害防治工程研究     

贺卫中 《中国煤田地质》2002,14(2):43-44

活鸡免矿井是神木北部矿区首批建设的现代化煤矿之一，于2000年12月投产，生产原煤800万t/a。由于该矿井范围内煤层上部（垂距21-30m）赋存有10.97km^2烧变岩裂隙含水层，其静储量高达130万m^3，单孔涌水量可达2000m^3/d，对煤矿的安全开采构成了巨大威胁。同时，烧变岩裂隙水双是可供矿区开发利用的宝贵水资源，为消除水害隐患及合理利用地下水资源，采用了钻孔泄水方式将烧变岩裂隙水引入矿区供水系统，既保证了矿井的安全生产，又取得了巨大的经济效益与环境效益。  相似文献   

3222工作面突水灾害成因与治理技术     

王广军  阎昌银等 《中国煤田地质》2002,14(4):52-54

通过对第四系“四含”长观孔、“太灰”长观孔、“奥灰”长观孔的水位观测及突水水质的化验,认为皖北矿务局祁东煤矿-420水平3222工作面发生的(涌水量达1670m3/h)特大突水灾害的突水水源应来自第四系第四含水层,其突水通道可能是:①工作面上方隐伏存在古河床切割的深沟,②工作面中存在垂向导水裂隙带,使“四含”水下泻所致。通过采用强排、截流、拔架及堵源的治理方案,恢复了矿井生产。  相似文献   

Tectono-metamorphic evolution of the Okcheon Metamorphic Belt, South Korea: Tectonic implications in East Asia   总被引：9，自引：0，他引：9  

Chang Whan Oh  Sung Won Kim  In-Chang Ryu  Toshinori Okada  Hironobu Hyodo  Tetsumaru Itaya 《Island Arc》2004,13(2):387-402

Abstract The tectonic history of the Okcheon Metamorphic Belt (OMB) is a key to understanding the tectonic relationship between South Korea, China and Japan. The petrochemistry of 150 psammitic rocks in the OMB indicates that the depositional environment progressively deepened towards the northwest. These data, combined with the distribution pattern of oxide minerals and the abundance of carbonaceous material, support a half‐graben basin model for the OMB. Biotite and muscovite K–Ar dates from metasediments in the central OMB range from 102 to 277 Ma. K–Ar ages of 142–194 Ma are widespread throughout the area, whereas the older ages of 216–277 Ma are restricted to the metasediments of the middle part of the central OMB. The younger (Cretaceous) ages are only found in metasediments that are situated near the Cretaceous granite intrusions. The 216–277 Ma dates from weakly deformed areas represent cooling ages of M1 intermediate pressure/temperature (P/T) metamorphism. The relationship between age distribution and deformation pattern indicates that the Jurassic muscovite and biotite dates can be interpreted as complete resetting ages, caused by thermal and deformational activities associated with Jurassic granite plutonism. Well‐defined ⁴⁰Ar/³⁹Ar plateau ages of 155–169 Ma for micas from both metasediments and granitic rocks can be correlated with the main Jurassic K–Ar mica ages (149–194 Ma). U–Pb zircon dates for biotite granite from the southwest OMB are 167–169 Ma. On the basis of the predominantly Jurassic igneous and metamorphic ages and the uniformity of d₀₀₂ values for carbonaceous materials in the study area, it is suggested that the OMB has undergone amphibolite facies M2 metamorphism after M1 metamorphism. This low P/T M2 regional thermal metamorphism may have been caused by the regional intrusion of Jurassic granites. The OMB may have undergone tectono‐metamorphic evolution as follows: (i) the OMB was initiated as an intraplate rift in the Neoproterozoic during break‐up of Rodinia, and may represent the extension of Huanan aulacogen within the South China block; (ii) sedimentation continued from the Neoproterozoic to the Ordovician, perhaps with several unconformities; (iii) M1 intermediate P/T metamorphism occurred during the Late Paleozoic due to compression caused by collision between the North and South China blocks in an area peripheral to the collision zone; and (iv) during the Early to Middle Jurassic, north‐westward subduction of the Farallon‐Izanagi Plate under the Asian Plate resulted in widespread intrusion of granites, which triggered M2 low P/T regional thermal metamorphism in the OMB. This event also formed the dextral Honam shear zone at the boundary between the OMB and Precambrian Yeongnam massif.  相似文献   

桩基础非线性工作性状的室内模型试验分析   总被引：1，自引：0，他引：1  

张鹤年  汤劲松  何立明 《岩土工程技术》2005,19(2):87-92

通过对单桩、带承台单桩和不同桩距群桩的模型试验结果分析 ,并与群桩试验的数值计算结果对比 ,总结了群桩中桩体的荷载传递规律 ;描述了板底土体反力和板下土体附加应力分布特性 ;比较了不同桩距群桩的荷载分担状况。通过试验结果的分析 ,得出桩的遮拦作用提高了承台下土体极限承载力的结论 ,为理论研究提供了试验依据 ;同时对桩的非线性工作状况进行分析 ,得出大桩距群桩受荷时桩先进入非线性然后承台下土体再进入非线性的结论。试验结果即验证了复合桩基非线性理论的若干假定 ,又为进一步研究提供了试验依据。  相似文献   

Long-term changes in cladoceran assemblages in the Danube floodplain area (Slovak–Hungarian stretch)     

Marta Illyov  Danka Nmethov 《Limnologica》2005,35(4):274-282

In this paper, the distribution of Cladocera species in the different sampling sites: the main channel/old river bed, parapotamal type side arms and plesiopotamal side arms, is described. The structure of cladoceran assemblages in the by-passed Danube section and in the adjacent floodplain water bodies has changed since the Gabčíkovo hydropower plant was put into operation. Great changes have been observed in the previous parapotamal side arm situated between river km 1840 and 1820, artificially fed with water from the head-race canal. The dominance of tychoplanktonic (benthic and phytophilous) species has increased, while the typical euplanktonic species have disappeared. Three characteristic groups of cladoceran assemblages were recorded when a different type of habitat was taken into consideration. Euplanktonic cladocerans prevailed on all sampling sites before damming. In periods after damming, littoral species, and later also a euplanktonic forms, dominated on the main channel sampling sites. In parapotamal and plesiopotamal side arms with rich littoral macrovegetation during periods after damming, phytophilous cladoceran species were the ones with the highest occurrence. The samplings from the first time period were rather homogenous. The samplings from the second and third period were more similar when considering the sample site than regarding the time period. In total, 64 cladoceran species were recorded in the course of 13 years (from 1991 to 2004). The increase in number of Cladocera species from 1991 to 2004 was significant. Chydorus sphaericus was found to be the most widely distributed species in the study area. The finding of Disparalona hamata is the first faunistic record from the central part of the Danubian watersheds.  相似文献   

用芳香化合物分布判别储层产液性质   总被引：1，自引：1，他引：1  

岳兴举  王振平  菅云英  孔令芳  颜红霞 《地球化学》2005,34(2):180-186

储层产液性质判别是录井、测井的基本任务,也是难题之一.特别在涉及到含水油层和含油水层的判别时,更是缺少可靠而有效的方法.利用芳香化合物在油水两相中的分配原理和反相液相色谱对芳香化合物的分离检测技术,测试了67块已知产液性质的储层样品,在此基础上,建立起了两张判别储层产液性质的地球化学图,其对油层、含水油层、含油水层及水层的综合对判率都在83%以上.  相似文献