Comment on 'Chemical remagnetization of the Upper Carboniferous–Lower Triassic Pyeongan Supergroup in the Jeongseon area, Korea: fluid migration through the Ogcheon Fold Belt' by Y.H. Park, S.-J. Doh and D. Suk     

Youngdo Park  Jin-Han Ree 《Geophysical Journal International》2006,164(3):481-483

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一次造成乌鲁木齐市电网瑶线铁塔倒塌事故的气象原因分析     

窦新英  宾建华蒋军 《沙漠与绿洲气象(新疆气象)》2005,28(5):32-34

为了解2004年11月24日乌鲁木齐市两座电网瑶线铁塔倒塌事故的气象原因，通过实地调查，并对高低空环流形势场、加密气象站信息等进行了分析。结果表明，乌鲁木齐地区不同地理位置风速差异很大，红雁池和头屯河区瞬间极大风速分别比市区大12．8m／s和18．4m／s。纠正了过去认为东南大风的强中心只出现在红雁池附近的说法，为今后制作大风分区预报提供了参考，也可为城区高层建筑及相关设计规范的修正提供借鉴。  相似文献   

中朝板块元古宙板内地震带与盆地格局   总被引：34，自引：3，他引：34  

乔秀夫 《地学前缘》2002,9(3):141-149

地史中发生的强地震事件在地层中留下固定的记录 (图 1～ 3) ,这些记录在区域上呈带状分布 ,代表地史中的地震带。中朝板块元古宙目前可识别出两个板内地震带 (图 5 )。中元古代板内地震带 (170 0～ 12 0 0Ma)西起太行山北段 ,经燕山山脉、辽宁西部、穿越辽河平原至辽宁北部的泛河流域分布 ,即燕山—泛河地震带 ,现今呈NEE向延伸。新元古代震旦纪地震带沿吉林南部、辽东半岛、山东中部及苏皖北部现今呈NNE走向分布 ,即古郯庐地震带 (6 5 0～ 6 0 0Ma)。上述两个板内地震带是元古宙不同时期超大陆裂解的响应。中元古代与新元古代两个不同方向的地震断裂带分别控制着两个时期的盆地边界。燕山泛河地震断裂带构成中元古代海盆南界 (指现在的位置 ) ,形成向北开放的海域。古郯庐地震断裂带将中朝板块裂解为华北块体与胶辽朝块体。古郯庐地震断裂带构成震旦纪海域的边界 ,震旦纪海盆通过朝鲜半岛与当时的外海相连接 ,华北块体则为陆源剥蚀区。文内四幅古地理图 (图 6～ 9)是以地震灾变思想为指导 ,以新的地层研究、对比为基础编制的 ,侧重反映了盆地的格局及其变化。根据地震、同沉积断裂新的思路 ,可提供地质学家重新认识与解释某些沉积矿床的成因 ,它们的成矿元素均来自地球深部而非地表风化作用。文中编制  相似文献   

Sulfur Content and Isotopic Ratio of Cambro-Ordovician Carbonate Rocks from South Korea: A Possible Source for Mesozoic Magmatic-hydrothermal Ore Sulfur     

Shunso ISHIHARA  Myung–Shik JIN  Yoshimichi KAJIWARA 《Resource Geology》2002,52(1):41-48

Abstract: Carbonate rocks of Cambrian (18 samples) and lower-middle Ordovician (11 samples) ages from South Korea were analyzed for sulfur contents of structurally substituted sulfate (SSS) and sulfides and their δ³⁴S values. The δ³⁴S values of SSS ranging from +25.9 to +45.2 permil, are averaged as +33.6 and +33.5 permil for the Cambrian and Ordovician rocks, respectively, which indicate high δ³⁴S values of the Cambro-Ordovician seawater. The SSS contents in the carbonate rocks are low being 2.9 to 17.3 ppm S (averaged as 7.0 ppm S). Sulfide sulfur, on the contrary, is much abundant containing 3 to 1,880 ppm S and the δ³⁴S values range widely between –17.6 and +31.1 permil. Sulfide sulfur of the studied rocks excluding impure carbonates has an average content of 187 ppm S and δ³⁴S value of +12.8 permil (n=24). The estimated δ³⁴S (sulfate–sulfide) values, which range from 13.8 to 25.4 permil in general with a few exceptions from 36.5 up to 52.3 permil for some impure carbonates, may provide evidence for the persistent oceanic anoxia with its temporary recovery during the Cambro-Ordovician time.
The SSS and sulfide sulfurs have often higher δ³⁴S values than the Mesozoic-Cenozoic ore sulfur (Ishihara et al., 2000). Since carbonate rocks are very reactive with circulating hydrothermal ore solution, high δ³⁴S values of the Korean ore deposits might be caused to some extent by ³⁴S enrichment from the host carbonates, resulting in the low SSS contents observed.  相似文献   

黄海及其沿岸历史地震初步研究     

吴戈  刘昌森  江在雄  翟文杰  吴镝 《四川地震》2002,(2):14-22

黄海及其边缘，经历史地震资料整理，地震参数估定与编目，截至1949年8月，共有M≥3级地震2187次，其中M≥43/4级地震259次，资料显示大致有三个相对集中活跃区，16世纪曾有过历史地震活动高潮。  相似文献   

Palaeomagnetic and rock-magnetic studies of Cretaceous rocks in the Gongju Basin, Korea: implication of clockwise rotation   总被引：2，自引：0，他引：2  

Seong-Jae Doh  Wonnyon Kim  Dongwoo Suk  Yong-Hee Park  Daekyo Cheong 《Geophysical Journal International》2002,150(3):737-752

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Monsoonal precipitation variation in the East Asia since A.D. 1840 ——Tree-ring evidences from China and Korea     

刘禹  Won-Kyu Park  蔡秋芳  Jung-Wook Seo  Hyun-Sook Jung 《中国科学D辑(英文版)》2003,46(10)

The main characteristic of the East Asian climate is the monsoon system. Plenty of studies have demonstrated that the Asian monsoon system plays a crucial role in the global climate sys- tem [1-4]. The Asian summer monsoon can be divided into two parts, t…  相似文献   

Dinosaur tracks from the Cretaceous of South Korea: Distribution, occurrences and paleobiological significance   总被引：2，自引：0，他引：2  

Min Huh  Koo Geun Hwang  In Sung Paik  Chull Hwan Chung  Bo Seong Kim 《Island Arc》2003,12(2):132-144

Abstract   Abundant dinosaur fossils including dinosaur footprints, eggs and nests, teeth and bones have been found from the Cretaceous non-marine deposits of Korea. Among them, dinosaur tracks are the most distinctive, and some track sites are among the most famous in the world. Until now, 27 dinosaur track localities have been discovered from the Cretaceous strata in the Gyeongsang Basin and several small basins. Ornithopod tracks are most abundant at most Korean track sites, and most of them are identified as Caririchnium ; that is, large ornithopod footprints with wide hoof impressions. Most theropod tracks are found in Neungju Basin and they consist of various types of small or medium-sized bird-like footprints, and other large footprints. Sauropod tracks are also abundant in the Gyeongsang Basin. The sauropod tracks vary in size, shape, and pattern of trackway, and suggest that diverse sauropods existed in this area. These diverse tracks in South Korea suggest that various dinosaurs flourished at the margins of lakes distributed in the southern part of the Korean Peninsula during the Cretaceous.  相似文献   

Tectonic elements with South China affinity in the Korean Peninsula: new Early Jurassic palaeomagnetic data   总被引：1，自引：0，他引：1  

Koji Uno  Tae Woo Chang  Kuniyuki Furukawa 《Geophysical Journal International》2004,158(2):446-456

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Mineral chemistry of spinel peridotite xenoliths from Baengnyeong Island, South Korea, and its implications for the paleogeotherm of the uppermost mantle     

Sung Hi  Choi  Sung-Tack  Kwon 《Island Arc》2005,14(3):236-253

Abstract   The mantle-derived xenoliths entrained in the Pliocene basanite from Baengnyeong Island, South Korea, are spinel lherzolites and spinel harzburgites. The overall compositional range of the Baengnyeong xenoliths matches that of the post-Archean xenoliths of lithospheric mantle origin from eastern China, but without any compositional evidence for a refractory Archean mantle root. Mineral compositions of the xenoliths have been used to estimate the equilibrium temperatures and pressures, and to construct a paleogeothermal gradient of the source region. The xenolith-derived paleogeotherm is constrained from about 820°C at 7.3 kbar to 1000°C at 20.6 kbar. Like those from the post-Archean Chinese xenoliths of lithospheric mantle origin, the Baengnyeong geotherm is considerably elevated relative to the conductive models at the depth of the crust–mantle boundary, reflecting a thermal perturbation probably related to lithospheric thinning. There is no significant P / T difference between harzburgite and lherzolite, which suggests that the harzburgites are interlayered with lherzolites within the depth interval beneath Baengnyeong Island.  相似文献