微生物和有机质在512层间氧化带砂岩型铀矿成矿中的作用   总被引：15，自引：3，他引：12  

赵瑞全  秦明宽 《铀矿地质》1998,14(6):338-343,379

微生物和有机质成矿作用的研究近年来在国外很活跃,而国同其在砂岩型铀矿形成中的作用研究 够深入,本文通过对微生物和有机质成矿作用的分析,探讨了共在５１２层间化带砂岩型铀矿成矿中的作用,以期对找矿有所帮助。  相似文献   

Understanding the spatial distribution and physical attributes of upland swamps in the Sydney Basin as a template for their conservation and management     

Kirstie A. Fryirs  Will Farebrother  Grant C. Hose 《The Australian geographer》2019,50(1):91-110

Temperate Highland Peat Swamps on Sandstone (THPSS) and Coastal Upland Swamps in the Sydney Basin (CUSSB) are listed as endangered ecological communities under Australia's national and state legislation. They are threatened by a range of human and climate impacts. Across the region there are 3208 individual, valley-bottom, elongate-shaped, upland swamps that drain first- or second-order drainage lines and small catchment areas (mean?=?0.25?km²). They occur at a median distance of 57?km from the coast in areas with an average annual rainfall of 1505?mm/year and average annual temperature of 15°C. Those closer to the coast occur on elevations as low as 160?m a.s.l., and those further from the coast, on plateau country, occur up to 1172?m a.s.l. (median 634?m a.s.l.). The valleys that contain these swamps terminate downstream at a valley constriction or bedrock step, behind which alluvial materials have accumulated, and peat has formed to produce relatively steep swamps (median slope 6.2 per cent). Understanding the spatial distribution and physical attributes of these systems, and having the accompanying maps as a resource, is critical for development of sound, well-informed conservation, rehabilitation and monitoring programs, and for analysing the ecosystem services they provide.  相似文献   

山东省砂岩热储地热资源开发利用模式探讨   总被引：1，自引：0，他引：1       下载免费PDF全文

秦耀军  张平平 《山东国土资源》2018,34(10)

通过对山东省砂岩热储地热资源、开发利用现状及存在问题的分析,结合社会、经济、环境效益及清洁能源应用需求,提出了地热供暖、梯级利用、多级取热、尾水回灌为适合山东省砂岩热储地热资源合理开发、高效利用及采灌均衡可持续开发利用模式。以此模式建立的山东省首个砂岩热储地热回灌示范工程——德州市水文家园,示范效果良好,促进了山东省鲁北地区地热供暖产业的持续健康发展,实现了社会、经济、生态环境的共赢。  相似文献   

Reviews of the Destruction and Preservation of Primary Porosity in the Sandstone Reservoirs     

《地球科学进展》2012,27(1)

埋藏条件下原生孔隙的破坏与保存机制是含油气盆地砂岩储层质量研究的一个核心领域,其在油气地质学研究中的意义不言而喻。与次生孔隙的形成与保存机制相比,影响原生孔隙破坏与保存的因素有着其特殊的复杂性和多样性。在总结国内外研究进展的基础上,试图深入理解不同成岩机制在砂岩储层原生孔隙破坏与保存中的意义和作用,包括破坏机制（如机械压实、胶结作用等）和保存机制（如地层超压、颗粒包膜、盐体侵位和烃类占位等）。目前难以实现砂岩储层质量钻前准确预测的一个困难在于无法明确原生孔隙演化的动力和过程,将来成岩作用、流体作用、沉积过程和盆地演化的更紧密结合可能是解决砂岩储层原生孔隙破坏与保存机制研究中最有希望的发展方向之一。  相似文献   

Preliminary results from U-Th dating of glacial-interglacial deposition cycles in a silica speleothem from Venezuela     

J. Lundberg  C. Brewer-Carias 《Quaternary Research》2010,74(1):113-365

Recent explorations in Cueva Charles Brewer, a large cave in a sandstone tepui, SE Venezuela, have revealed silica biospeleothems of unprecedented size and diversity. Study of one — a sub-spherical mass of opaline silica — reveals a complex, laminated internal structure consisting of three narrow dark bands alternating with two wider light bands. Uranium-thorium dating has produced 3 stratigraphically correct dates on the light bands from 298 ± 6 (MIS 9) to 390 ± 33 ka (MIS 11). U concentration is only 30-110 ppb. Initial ²³⁴U/²³⁸U ratios are high and increase over time from 1.8 to 5.3. Growth rate is very low, the fastest, at 0.37 ± 0.23 mm/ka, in MIS 9. Trace element and heavy metal content of the dark bands is distinctly higher than that of the light bands. It is hypothesized that the dark and light bands correlate with drier/glacial and wetter/interglacial periods, respectively, and that this sample probably began to grow in MIS 13. The cave is in a region that straddles a regionally important ecotone: the speleothem isotopic and trace element variations may preserve a useful paleoclimatic signal. This is the first published suite of U-Th dates from a single silica speleothem and the longest Quaternary record for this region.  相似文献   

新疆阿克库勒凸起西南缘托浦台泥盆系东河砂岩沉积特征          下载免费PDF全文

翟振飞  傅恒 《沉积与特提斯地质》2010,30(1):73-77

本文在综合分析阿克库勒凸起西南缘的托浦台泥盆系的三维地震资料和24口井的录井、测井、岩芯、薄片资料的基础上,将研究区泥盆系划分为包括一个海侵体系域和一个高位体系域的三级层序。海侵体系域主要发育远滨和近滨沉积,高位体系域主要发育近滨和前滨沉积。  相似文献   

Microstructural weathering of sedimentary rocks by freeze–thaw cycles: Experimental study of state and transfer parameters     

Alice Saad  Sylvine GuédonFrançois Martineau 《Comptes Rendus Geoscience》2010,342(3):197-203

The frost sensitivity of a rock is resulting from the combined action of processes linked to porous network characteristics (state parameters) and to the way water flows into this porous network (transfer parameters), our study was thus about the influence of these parameters on frost weathering of rocks. Sedimentary rocks often found on buildings (limestone and sandstone) and consequently submitted to temperature variations have been selected. State and transfer parameters have been measured for sample characterization and the follow-up of weathering during freeze–thaw cycles. The coupled influence of a state parameter (dynamic modulus of elasticity) and a transfer parameter (water permeability), i.e. between rock skeletal strength and voids connection, has thus been discussed.  相似文献   

伊犁盆地南缘某矿床构造与铀成矿关系   总被引：4，自引：0，他引：4  

蒋宏  张占峰  刘铭艳 《新疆地质》2011,29(3):327-331

某矿床是伊犁盆地南缘地浸砂岩型铀矿田重要组成部分,矿床地质构造及成矿模式有别于铀矿田内其它矿床.通过构造单元划分,矿床定位于盆地南缘构造活动区.新构造运动以来,频繁的多期次构造活动造就褶皱、断裂发育.盆缘适度抬升为层间氧化带发育提供势能的同时,主控矿断裂产出部位及性质决定了地下水补径排体系、层间氧化带发育空间和铀矿化的赋存部位.据区域地质构造活动事件和断层泥石英碎砾微观特征分析划分出控矿断裂的6个活动期次与利用矿石U-Pb同位素年龄划分出的4个成矿期次在时间上具对应关系,构造运动的间歇期是铀主成矿期,多期次构造活动导致铀成矿具多期和多阶段性.  相似文献   

鄂西渝东区建南气田及周缘志留系致密砂岩储层评价     

马登峰 《海相油气地质》2011,16(1):14-19

鄂西渝东区建南气田及周缘志留系为一套海相致密碎屑岩沉积.沉积厚度1 000～1 450m,为南方海相地层的重要油气勘探层系之一.据对该区志留系砂岩储层野外露头剖面和岩心的观察以及薄片分析,志留系砂岩主要岩石类型为富石英的长石石英砂岩和岩屑石英砂岩,粒度以极细粒为主,少部分为细粒,成分成熟度和结构成熟度较高.储层类型主要...  相似文献   

广西姑婆山地区矿产远景调查主要成果与进展     

唐专红  李玉坤  张能  魏巧仙  吴年冬  唐娟红  荣红  彭展 《华南地质与矿产》2011,27(4):352-357

在广西姑婆山地区完成的矿产远景调查项目,在地层、岩浆岩、区域构造、物化探、矿产等方面取得重要进展。对地层进行了多重地层划分与对比,建立了非正式地层单位——开山砂岩;新发现三门．鹰阳关晋宁一加里东期NE向韧性剪切带,建立了区域构造格架,阐明了构造形成演化历史。通过对调查区地、物、化、遥等调查研究,发现一批矿产异常,提交新...  相似文献