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991.
北祁连中西段发育三套早古生代蛇绿岩及相应的基性、超基性岩,呈北、中、南三条带状分布。区内金的活化、迁移主要受控于超基性岩带和与其分布近于一致的两条韧性剪切带,金矿化主要发生在强蚀变超基性岩体内、岩体与围岩接触带、断裂破碎蚀变带内。根据包裹体测温及成分测定、稳定同位素特征资料及超基性岩中金丰度值等分析,金矿物质主要来自超基性岩,流体来源于深部,其成因属与超基性岩有关的韧性剪切带型金矿床。 相似文献
992.
Average slip rate,earthquake rupturing segmentation and recurrence behavior on the Litang fault zone,western Sichuan Province,China 总被引:3,自引:0,他引:3
XU Xiwei WEN Xueze YU Guihua ZHENG Rongzhang LUO Haiyuan & ZHENG Bin . Institute of Geology China Earthquake Administration Beijing China . Earthquake Administration of Sichuan Province Chengdu China 《中国科学D辑(英文版)》2005,48(8):1183-1196
The Litang fault zone (LFZ) is an important active fault within the northwestern Sichuan sub-block. To-gether with the Garzê-Yushu, Xianshuihe, and An-ninghe fault zones on its northern, eastern and south-eastern sides, the LFZ constitutes the lateral extrusion tectonic system in the southeastern part of the Qing-hai-Tibetan Plateau[1,2] (Fig. 1). According to instru-mental records, historical recordings and field investi- gation, an earthquake (Ms7.3) occurred on its middle to south se… 相似文献
993.
LIU Xuhua WANG Jinfeng LIU Mingliang & MENG Bin . Institute of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing China . Graduate School of the Chinese Academy of Sciences Beijing China . College of Arts Sciences of Beijing Union University Beijing China . School of Forestry Wildlife Sciences Auburn University Auburn Alabama AL USA 《中国科学D辑(英文版)》2005,48(12):2231-2240
Along with the increasing problems of rapid popu-lation increase, resources scarcity and environment deterioration, the interaction between human devel-opment and natural environment changes, especially the Land-Use/Land-Cover, LUCC issue is becoming a frontier and hot field[1], in which investigation on the mechanisms of land use change is one of the three core issues. Deficient natural resources, in particular the shortage of cropland resource in China, are the important constraints to Ch… 相似文献
994.
Energy distributions of the large-scale horizontal currents caused by wind in the baroclinic ocean 总被引:3,自引:0,他引:3
ZHOU Lei TIAN Jiwei & WANG Dongxiao . Physical Oceanography Laboratory Ocean University of China Qingdao China . Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangdong China 《中国科学D辑(英文版)》2005,48(12):2267-2275
Wind is the main energy source for the generation of the internal waves and the ocean mixing. Wunsch[1] estimated that about 1 TW (1 TW = 1012 W) energy was transported into the ocean from the winds by us-ing the altimeter data. Watanabe et al.[2] numerically calculated that the mixing processes obtained 0.7 TW energy from the global wind, which afforded most of the energy needed by the maintenance of the Merid-ional Overturning Circulation (MOC). During the past 50 years, in the Norther… 相似文献
995.
Advances in the Study on Nutrient Requirements of Grouper(Epinephelus sp. ):a Review 总被引:1,自引:0,他引:1
LUOZhi LIUYongjian MAIKangsen TIANLixia 《中国海洋大学学报(英文版)》2005,4(2):93-98
The paper reviews the recent advances in studying grouper nutrition requirement for the development of cost-effective and environmentally friendly artificial diets. It consists of seven parts: protein and amino acid, lipid and essential fatty acid, carbohydrate, vitamin, mineral, alternative protein source, broodstock and larval nutrition. The review provides some basic information for further investigation of nutrient requirements of groupers. 相似文献
996.
The effects of recombinant eel growth hormone (reGH).methyltestosterone (MT)and L-thyroxine (T4)on the growth of red sea bream. Pagrosomus major.were investigated.Administration of reGH to fry by immersion at 2 mg 1 for 2 hevery 5 dsys resulted in significant increase in both weight and length.but the condition factor (CF) diminished relative to that of similarly treated controls over the 37day treatment period.Immersion in 0.1 mg:1 T4 also resulted in significant increase in both weight and length and higher survival rate of test fry compared to the controls. Immersion in MT had less effect on growth and high-dose resulted in high mortality.In the second study.injection of 2 μg reGH(gwk)caused a significant increase in the specific growth rate (SGR) of test red sea bream fingerlings relative to that of the controls during the 4-week treatment period and maintained the increasing trend over the post-treatment period (weeks 4-6).Injection of MT at a dosage of 1μg (gwk) resulted in a significant in-creas 相似文献
997.
Geospatial-temporal analysis of land-use changes in the Yellow River Delta during the last 40 years 总被引:5,自引:0,他引:5
Qinghua?YeEmail author Gaohuan?Liu Guoliang?Tian Shenliang?Chen Chong?Huang Shupeng?Chen Qingshen?Liu Jun?Chang Yanan?Shi 《中国科学D辑(英文版)》2004,47(11):1008-1024
Research on land use/land cover changes (LUCC)has been the core project of the Global EnvironmentalChanges since the 1990s[1—6]. Scientists at home andabroad have been laying emphasis on integrationstudies on land-use change by “space and process”features[7—10] as researches on LUCC are in a greatdeal. It is of paramount important for us to studyLUCC at various spatial-temporal scales and build aquantitative assessment of land-use conversion by in-tegrated spatial-temporal features. … 相似文献
998.
999.
东河砂岩是塔里木盆地主要的勘探目的层和产油层之一。经过多年艰苦勘探和多学科综合研究,现已认识到东河砂岩为晚泥盆世晚期至早石炭世早期海平面上升背景下沉积的一套海侵底砂(砾)岩,在盆地范围内是一个明显的穿时沉积体。东河砂岩以滨浅海相陆源碎屑沉积占优势,局部发育海陆过渡相陆源碎屑沉积。根据盆地内100多口井资料的岩石学特征、沉积特征以及其它指相标志的综合分析,在东河砂岩中识别出滨岸、河口湾、辫状河三角洲以及冲积扇等不同的沉积相类型,其中高能碎屑滨岸相最重要,分布最广。东河砂岩沉积早期和中期,盆地主要为高能碎屑滨岸相和碎屑陆棚相沉积,末期海侵达到最大,盆地内为碳酸盐台地沉积,而轮南及盆地北部一带受物源区的影响,出现混积滨岸和碎屑滨岸沉积。东河砂岩明显具有填平补齐的沉积特征,其砂体厚度在缓坡处减薄、陡坡处增厚、遇孤岛减薄或尖灭,这些沉积特征为形成东河砂岩非构造圈闭奠定了良好的地质基础。满加尔、轮南、塔中、玛扎塔格以及草湖地区都有可能找到该类油气藏(田),展示了东河砂岩非构造圈闭的良好勘探前景。 相似文献
1000.