德国大陆科学钻探计划的测井成就   总被引：3，自引：2，他引：1  

王祝文  李舟波 《世界地质》1998,17(2):67-72

德国大陆科学钻探计划（ＫＴＢ）经过８年多的努力,钻探了先导孔（ＶＢ）和主孔（ＨＢ）两口举世瞩目的科学钻孔。地球物理测井技术在这个计划中起到了不忽视的作用,本文简要介绍了在德国大陆学科钻探计划（ＫＴＢ）实施过程中,地球物理测井所取得的主要成就。  相似文献   

盆山转换与造盆、造山过程分析   总被引：3，自引：0，他引：3  

许效松 《沉积与特提斯地质》1998,18(6):1-10

盆地系统和造山带系统是大陆岩石圈上的两个主要构造单元,其包括地质历史中曾存在的和消失的盆地、大洋、大陆边缘及陆地。因此,盆山转换研究、探索盆转山和山控盆的过程则成为大陆地质的前沿研究领域。沉积地质学通过盆山转换和转换过程的分析研究,并以大陆边缘为主,对盆地分析、露头层序地层学研究,在盆地沉积相的时空配置和演化、大陆边缘转为前陆盆地过程中,分析海－陆环境在时空上的四个转换过程和自演化序列。盆山转换的另一关键是层序等时格架的建立。层序的等时性应包括层序界面（单一的和复合的界面）、层序和时间损失量。  相似文献   

大陆弹性岩石层有效弹性厚度对岩石层形变和大地水准面的动力影响     

熊熊  许厚泽  徐建桥  傅容珊 《大地测量与地球动力学》1998,(4)

用岩石层—地幔力学、热学耦合模型,以俯冲带为例,研究大陆岩石层不同的有效弹性厚度对岩石层形变和大地水准面起伏的动力影响。数值结果显示大陆岩石层有效弹性厚度的作用象一低通滤波器,它抑制岩石层形变和大地水准面起伏的高频分量。随着有效弹性厚度的增加,岩石层的形变和大地水准面起伏不仅幅度减小,其形状变化也被平滑。模拟结果表明,在进行大陆岩石层动力学过程的研究中,只有充分考虑大陆弹性岩石层有效弹性厚度的动力影响,才能更客观地描述研究客体。  相似文献   

新疆大地构造演化基本特征   总被引：63，自引：12，他引：51  

成守德  王元龙 《新疆地质》1998,(2)

新疆大地构造发展演化经历了 :1.古陆核及原始古陆的形成与解体 ;2 .元古宙末期( 80 0～ 90 0 Ma)联合古陆的形成 ;3.震旦—奥陶纪联合古陆裂解、古亚洲洋形成 ;4 .志留—泥盆纪古亚洲洋俯冲、消减 ;5.泥盆—早二叠世古特提斯洋打开 ,西伯利亚、哈萨克斯坦—准噶尔、塔里木板块聚合 ,亚洲北大陆形成 ,陆内裂陷或有限小洋盆发生 ;6.晚二叠—三叠纪北特提斯拉张成洋 ,由冈瓦纳分离出来的冈底斯中间板块于三叠纪末沿中特提斯洋拼贴于羌塘 (华南 )板块之上 ,并沿北特提斯洋 (康西瓦 )与亚洲北大陆聚合 ;7.侏罗纪班公错—怒江板内洋盆打开 ,晚侏罗世闭合 ;8.白垩—第三纪印度板块向北俯冲 ,拼贴于欧亚大陆南缘。由于陆内俯冲 ,山脉迅速抬升并向盆地推覆 ,形成了新疆复杂的构造格局  相似文献   

全面迭缩式不提钻换钻头技术应用于中国大陆科学钻探的前期研究   总被引：1，自引：0，他引：1       下载免费PDF全文

薛军  何德成  马孝春 《探矿工程》1998,(2):1-3

介绍了全面迭缩式不提钻换钻头钻具的结构、工作原理和使用特点,分析了此种钻具应用于中国大陆科学钻探中的前景及需要解决的问题。  相似文献   

陆相红盆地构造—岩性—岩相填图法新进展   总被引：8，自引：0，他引：8  

廖瑞君  刘邦秀 《江西地质》1998,12(1):8-14

构造＿岩性＿岩相填图法,经大量陆相红盆地再填图实践,在调研内容和认识上有较多重要补充和提高。笔者把这些新成果补充进方法中,进一步完善了填图方法,现就这方面成果作一系统介绍。  相似文献   

华夏古陆晚前寒武纪的活动痕迹   总被引：2，自引：0，他引：2  

邓家瑞  张志平 《华北地质》1998,21(2):1

通过对前寒武纪建造、构造的综合分析研究认为：中元古代晚期浙西-赣东北地区是华夏古陆的活动陆缘;武陵运动是华南一次最重要的造山运动,华夏古陆与扬子地块沿赣东北断裂带发生碰撞,形成了统一的“华南古大陆”。  相似文献   

义敦型镁铁—超镁铁岩的主要特征及其与蛇绿岩的对比   总被引：1，自引：0，他引：1  

张旗  李达周 《岩石学报》1990,6(3):33-42

“义敦型”相当于文献中通称的阿尔卑斯型,但却不是蛇绿岩。蛇绿岩代表洋壳和地慢的岩石组合,而义敦型镁铁-超镁铁岩体则是由陆壳下的地幔及其部分熔融的产物组成的。因此,蛇绿岩与义敦型岩体的构造含意不同,后者的分布与古缝合带无关。在造山带中区分开蛇绿岩和非蛇绿岩是至关重要的。义敦型镁铁-超镁铁岩组合的认定在理论上和找矿实践上都是有意义的。  相似文献   

Lateral terrestrial water flow contribution to summer precipitation at continental scale – A comparison between Europe and West Africa with WRF-Hydro-tag ensembles     

Joël Arnault  Benjamin Fersch  Thomas Rummler  Zhenyu Zhang  Gandome Mayeul Quenum  Jianhui Wei  Maximilian Graf  Patrick Laux  Harald Kunstmann 《水文研究》2021,35(5):e14183

It is well accepted that summer precipitation can be altered by soil moisture condition. Coupled land surface – atmospheric models have been routinely used to quantify soil moisture – precipitation feedback processes. However, most of the land surface models (LSMs) assume a vertical soil water transport and neglect lateral terrestrial water flow at the surface and in the subsurface, which potentially reduces the realism of the simulated soil moisture – precipitation feedback. In this study, the contribution of lateral terrestrial water flow to summer precipitation is assessed in two different climatic regions, Europe and West Africa, for the period June–September 2008. A version of the coupled atmospheric-hydrological model WRF-Hydro with an option to tag and trace land surface evaporation in the modelled atmosphere, named WRF-Hydro-tag, is employed. An ensemble of 30 simulations with terrestrial routing and 30 simulations without terrestrial routing is generated with random realizations of turbulent energy with the stochastic kinetic energy backscatter scheme, for both Europe and West Africa. The ensemble size allows to extract random noise from continental-scale averaged modelled precipitation. It is found that lateral terrestrial water flow increases the relative contribution of land surface evaporation to precipitation by 3.6% in Europe and 5.6% in West Africa, which enhances a positive soil moisture – precipitation feedback and generates more uncertainty in modelled precipitation, as diagnosed by a slight increase in normalized ensemble spread. This study demonstrates the small but non-negligible contribution of lateral terrestrial water flow to precipitation at continental scale.  相似文献   

Benthic responses to organic matter variation in a subtropical coastal area off SE Brazil     

Cintia O. Quintana  Marcos Y. Yoshinaga  Paulo Y. G. Sumida 《Marine Ecology》2010,31(3):457-472

Organic matter quality, expressed as the proportion of chlorophyll a (Chl a) to degraded organic material (i.e. phaeopigments), is known to influence the structure of benthic associations and plays an important role in the functioning of the ecosystem. This study investigates the vertical distribution of microbial biomass, meiofauna and macrofauna with respect to organic matter variation in Ubatuba, Brazil, a southeastern, subtropical coastal area. On three occasions, samples were collected in exposed and sheltered stations, at high and low hydrodynamic conditions. We hypothesize that benthic assemblages will have high meio‐ and macrofaunal densities and high microbial biomass at the sediment surface at the sheltered site, and lower and vertically homogeneous microbial biomass and densities of meio‐ and macrofauna are expected at the exposed site. The accumulation of fresh organic matter at the sediment surface was observed at both stations over the three sampling dates, which contributed to the higher densities of meiofauna in the first layers of the sediment column. Macrofauna followed the same trend only at the exposed station, but changes in the number of species, biodiversity and feeding groups were registered for both stations. Microbial biomass increased at the sheltered station over the three sampling dates, whereas at the exposed station, microbial biomass was nearly constant. Physical exposure did not influence organic matter loading at the sites and therefore did not affect overall structure of benthic assemblages, which negates our original hypothesis. Most of the benthic system components reacted to organic matter quality and quantity, but relationships between different‐sized organisms (i.e. competition and/or predation) may explain the unchanged microbial profiles at the exposed site and homogeneous vertical distribution of macrofauna at the sheltered site. In conclusion, the high quality of organic matter was a crucial factor in sustaining and regulating the benthic system, but coupled results showed that interactions between micro‐, meio‐ and macrofauna can be highly complex.  相似文献