深部天然核反应堆——一种可能的山脉隆升动力源   总被引：3，自引：0，他引：3       下载免费PDF全文

匡耀求  张本仁等 《地质论评》2001,47(2):119-128

板块碰撞造山模式难以解释造山作用在时间上的“滞后”和在空间上的“差位”现象，大量研究表明山脉隆升的动力来自深部，因此，探索深部地质过程的物理和化学机制及其导致的能量再分配是认识山脉隆升动力学机制的关键，若干线索表明地幔中的核反应中可能在岩石圈动力学演化过程中起过不可忽视的作用，通过分析U，Th等元素的地球化学性质及其在深变质过程中的行为，认为伴随板块俯冲发生的陆壳物质向地幔的再循环有可能在办流圈顶部形成富含U，Th,K等放射性亲石元素和碳质（石墨）的地质体，通过理论上的论证和对Oklo天然核反应堆遗迹的反演表明这些地质体可能有一部分具备了形成石墨核反应堆的条件。这种反应堆在亚临界状态下的断续运行有可能为其上方岩石圈中的岩浆作用提供热源，进入超临界状态时将可能导致深部核爆炸，成为地震，火山爆发和岩石圈破裂的动力来源，据此建立的山脉隆升的动力学初步模式，可以解释造山带的形成，高原的隆升，深源地震及其前兆的成因和金刚石及其相关岩石地壳浅部置位的机制。  相似文献   

青藏高原的隆升：青藏高原的岩石圈结构和构造地貌   总被引：20，自引：1，他引：20       下载免费PDF全文

崔军文  李朋武等 《地质论评》2001,47(2):157-163

笔者回顾青藏高原隆升研究的历史，剖析各种隆升动力学模式，依据着青藏高原岩石圈组成的构的强烈不均一性和、三分性”，“对称性”构造地貌格局，提出了青藏高原隆升是印度地块和塔里木一可拉善地块双向不均一俯冲和青藏腹地深层热隆扩展联合作用的结果，俯冲是高原隆升的重要机制，而热隆扩展是高原隆升的直接原因。  相似文献   

藻类勃发—湖相油源岩形成的一种重要机制   总被引：38，自引：0，他引：38       下载免费PDF全文

刘传联  徐金鲤等 《地质论评》2001,47(2):207-210

浮游藻类是重要的湖相生油母质，本文以渤海湾盆地济阳坳陷早第三纪湖相生油岩为例，研究了其中藻类（主要是颗石藻和沟鞭藻＿化石的分布特征，并通过与现代水体中藻类生产和沉积作用的比较，探讨了生油湖泊中藻类生产和沉积方式及其对油源岩形成所起的控制作用，结果显示，藻类勃发现象在早第三纪生油湖泊中相当普遍，而且贯穿于各类油源岩的形成过程，这类快速事件性沉积是湖相油源岩形成的一种重要机制。  相似文献   

华北地块东段和龙超镁铁质科马提岩的发现及特征          下载免费PDF全文

刘劲鸿 《地质论评》2001,47(4):420-424

和龙岩体赋存于新太古代夹皮沟—金城洞花岗绿岩带中,与围岩发生同变形变质。岩体具有典型的科马提岩冷凝结构分层和鬣刺结构、冷凝多面体节理。上述特征是作者1990年发现确认的。该科马提岩的矿物学特征:玻璃质脱玻形成铁皂石等矿物;斜方辉石和橄榄石鬣刺呈中空骸晶状,大部被滑石、铁白云石、绿泥石、磁铁矿等取代,但仍保留完好的长柱状假像;堆积带中橄榄石呈微细粒、新鲜,仅发生网状蛇纹石化。岩石化学特征富MgO,CaO/Al_2O_3=1.04,用科马提岩分类图判别为超镁铁质科马提岩。  相似文献   

天然气的无机元素的土壤化探元素预测指标的探索   总被引：1，自引：0，他引：1  

赵琦  罗正春  刘永平 《四川地质学报》2001,21(4):229-232

通过德阳新场气田化探成果与气田上有机元素异常，物探异常和钻孔实际见气的对比，以及对成都地区，宜宾地区化探成果的综合研究，认为As,Sb,Hb,Ba,Mn五元素及Cu,Pb,Zn,Mo,Cd,Ni,V,P等是预测天然气的指标，用该指标对新场气田和成都地区实际勘察结果对照，证实预测指标是正确的，从而探索出一条利用化探无机元素异常寻找天然气的新路。  相似文献   

Petrogenesis of Cenozoic Potassic Volcanic Rocks in the Nangqen Basin   总被引：2，自引：0，他引：2  

SUN Hongjuan  DENG Wanming  ZHANG YuquanInstitute of Geology  Geophysics  Chinese Academy of Sciences  Beijing Guangzhou Institute of Geochemistry  Chinese Academy of Sciences  Guangzhou 《《地质学报》英文版》2001,75(1)

The Nangqen basin is one of the Tertiary pull-apart basins situated in the east of the Qiangtang block.Similar to the adjacent Dengqen basin and Baxoi basin, there occurred a series of potassic volcanic and sub-volcanic rocks, ranging from basic, intermediate to intermediate-acid in lithology.Based on the study of petrology, mineralogy and geochemistry, including REEs, trace elements, isotopic elements and chronology, the authors concluded that the Cenozoic potassic volcanic rocks in the Nangqen basin were formed in the post-collisional intraplate tectonic settings. The relations between the basic, intermediate and intermediate-acid rocks are neither differentiation nor evolution, but instead the geochemical variability is mainly attributable to the different partial melting degrees of the mantle sources formed at depths of 50-80 km.The sources of the potassic rocks are enriched metasomatic mantle that has experienced multiple mixing of components mainly derived from the crust. The recycling model can b  相似文献   

Early Carboniferous Radiolarian Fauna from Heiyingshan South of the Tianshan Mountains and Its Geotectonic Significance   总被引：5，自引：0，他引：5  

LIU YuInstitute of Geology  Chinese Academy of Geological Sciences  Baiwanzhuang Ro  Beijing 《《地质学报》英文版》2001,75(1):101-108

Abundant and well-preserved fossil radiolarians found from the Artencasher Formation, Heiyingshan of Baicheng County, Xinjiang Uygur Autonomous Region, are identified, including 15 species and 2 unnamed species in 9 genera. The fauna is dominated by the Family Entactiniidae of Spumellaria. According to the faunal characteristics, the radiolarians may be divided into five assemblages, namely, the Triaenosphaera sicarius, Entatinosphaera palimbola, Entactinia vulgaris, Belowea cf. variabilis and Archocyrtium sp assemblages. The fauna may be correlated with that from the Early Carboniferous of Frankenwald and Rein in Germany. Thus, ophiolite was formed in the Carboniferous, while the age of collision between the Ili plate and the Tarim plate is Early Carboniferous.  相似文献   

Early-Middle Permian Reef Frameworks and Reef-building Models in the Eastern Kunlun Mountains   总被引：3，自引：0，他引：3  

TIAN Shugang Institute of Geology  Chinese Academy of Geological Sciences  Beijing  FAN Jiasong Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing 《《地质学报》英文版》2001,75(2):115-125

Reef frameworks and building models of the Early-Middle Permian in the eastern Kunlun Mountains have been verified through studies of reef-building communities, palaeoecology and carbonate facies. The eastern Kunlun reefs are built mainly by 6 reef-building communities, which include 11 major categories of frame-building organisms and 6 categories of reef-associated organisms. Eight types of reef-frames have been distinguished and eleven kinds of rocks identified to belong to 6 reef facies. Three sorts of reefs classified by previous researchers, namely mudmounds, knoll reefs and walled reefs, are well developed in the study area. Such reef-facies association and reef distribution show that there are 4 models of reef growth and development, i.e. the tidal-bank knoll-reef model, the plateau-margin wall-reef model, the composite wall-reef model and the deep-water mudmound model. The reefs are mainly constructed by calcareous sponge and calcareous algae, which are similar to all Permian reefs in other area  相似文献   

Post-Collisional Ductile Extensional Tectonic Framework in the UHP and HP Metamorphic Belts in the Dabie-Sulu Region, China   总被引：11，自引：1，他引：11  

SUO Shutian  ZHONG Zengqiu  YOU Zhendong  ZHANG Zeming Faculty of Earth Sciences  China University of Geosciences  Wuhan Institute of Geology  Chinese Academy of Geological Science  Beijing 《《地质学报》英文版》2001,75(2):151-160

The present-day observable tectonic framework of the ultrahigh-pressure (UHP) and high-pressure (HP) metamorphic belts in the Dabie-Sulu region was dominantly formed by an extensional process, mostly between 200 and 170 Ma, following the Triassic collision between the Sino-Korean and Yangtze cratons. The framework that controls the present spatial distribution of UHP and HP metamorphic rocks in particular displays the typical features of a Cordilleran-type metamorphic core complex, in which at least four regional-scale, shallow-dipping detachment zones are recognized. Each of these detachment zones corresponds to a pressure gap of 0.5 to 2.0 GPa. The detachment zones separate the rocks exposed in the region into several petrotectonic units with different P-T conditions. The geometry and kinematics of both the detachment zones and the petrotectonic units show that the exhumation of UHP and HP metamorphic rocks in the Dabie-Sulu region was achieved, at least in part, by non-coaxial ductile flow in the mul  相似文献   

Application of the Sequence Stratigraphy in the Study of Cretaceous-Tertiary of the Tarim Basin, Xinjiang, China     

DING Xiaozhong  GUO Xianpu  PENG Yang  JI Yunlong  WANG Yineng Institute of Geology  Chinese Academy of Geological Sciences  Beijing    China University of Geosciences  Beijing    Northwestern Bureau of Petroleum Geology  SINOPEC  Urumqi   《Continental Dynamics》2001,(2)

1. IntroductionThe Tarim basin, one of the most developed and important areas of marine Cretaceous-Tertiary in China except for south Tibet, is very rich in oil and gas, such as Kekeya oilfield in southwestern Tarim and Kela2 gas field in northeastern Tarim. Because of the expansion, subduction of the oceanic crust of the Tethys and the collision between the India plate and the Eurasia plate during the Cretaceous-Tertiary, the Tethys transgressed into the Tarim basin from west to east fr…  相似文献