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本文主要介绍各学科实用化攻关与综合预报以及专家系统等软件组成的统一软件系统,使该软件系统与在 IBM 机和 VAX 机上建立的数据库联接起来,并介绍了该系统的主要功能。 相似文献
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Permian Fusuline Fauna from the Lower Part of the Lugu Formation in the Central Qiangtang Block and its Geological Implications 总被引:2,自引:0,他引:2
A Kubergandian (Kungurian) fusuline fauna from the lower part of the Lugu Formation in the Cuozheqiangma area,central Qiangtang Block is described.This fusuline fauna belongs to the Southern Transitional Zone in palaeobiogeography,and is characterised by the presence of the distinctive bi-temperate genus Monodiexodina and many genera common in lower latitude Tethyan areas such as Parafusulina and Pseudodoliolina.The occurrence of Monodiexodina in the fauna confirms that the seamount-type carbonates of the Lugu Formation did not originate from the Palaeotethys Ocean,but rather from a branch of the Neotethys Ocean after the rifting of the Qiangtang Block from the Tethys Himalaya area in the Artinskian. 相似文献
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Shen Boheng Shen Shuzhong Wu Qiong Zhang Shuichang Zhang Bin Wang Xiangdong Hou Zhangshuai Yuan Dongxun Zhang Yichun Liu Feng Liu Jun Zhang Hua Shi Yukun Wang Jun Feng Zhuo 《中国科学:地球科学(英文版)》2022,65(6):983-1011
Science China Earth Sciences - The Carboniferous-Permian strata in the North China Block (NCB) contain abundant fossils, coals and natural gases. Establishing a high-resolution timescale for the... 相似文献
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Shen Shuzhong Zhang Hua Zhang Yichun Yuan Dongxun Chen Bo He Weihong Mu Lin Lin Wei Wang Wenqian Chen Jun Wu Qiong Cao Changqun Wang Yue Wang Xiangdong 《中国科学:地球科学(英文版)》2019,62(1):154-188
A series of global major geological and biological events occurred during the Permian Period. Establishing a highresolution stratigraphic and temporal framework is essential to understand their cause-effect relationship. The official International timescale of the Permian System consists of three series(i.e., Cisuralian, Guadalupian and Lopingian in ascending order) and nine stages. In China, the Permian System is composed of three series(Chuanshanian, Yansingian and Lopingian) and eight stages, of which the subdivisions and definitions of the Chuanshanian and Yangsingian series are very different from the Cisuralian and Guadalupian series. The Permian Period spanned ~47 Myr. Its base is defined by the First Appearance Datum(FAD) of the conodont Streptognathodus isolatus at Aidaralash, Kazakhstan with an interpolated absolute age 298.9±0.15 Ma at Usolka, southern Urals, Russia. Its top equals the base of the Triassic System and is defined by the FAD of the conodont Hindeodus parvus at Meishan D section, southeast China with an interpolated absolute age 251.902±0.024 Ma. Thirty-five conodont, 23 fusulinid, 17 radiolarian and 20 ammonoid zones are established for the Permian in China, of which the Guadalupian and Lopingian conodont zones have been served as the standard for international correlation. The Permian δ13 Ccarbtrend indicates that it is characterized by a rapid negative shift of 3–5‰ at the end of the Changhsingian, which can be used for global correlation of the end-Permian mass extinction interval, but δ13 Ccarbrecords from all other intervals may have more or less suffered subsequent diagenetic alteration or represented regional or local signatures only. Permian δ18 Oapatitestudies suggest that an icehouse stage dominated the time interval from the late Carboniferous to Kungurian(late Cisuralian). However, paleoclimate began to ameriolate during the late Kungurian and gradually shifted into a greenhouse-dominated stage during the Guadalupian.The Changhsingian was a relatively cool stage, followed by a globally-recognizable rapid temperature rise of 8–10°C at the very end of the Changhsingian. The87 Sr/86 Sr ratio trend shows that their values at the beginning of the Permian were between 0.70800,then gradually decreased to the late Capitanian minimum 0.70680–0.70690, followed by a persistent increase until the end of the Permian with the value 0.70708. Magenetostratigraphy suggests two distinct stages separated by the Illawarra Reversal in the middle Wordian, of which the lower is the reverse polarity Kiaman Superchron and the upper is the mixed-polarity Illawarra Superchron. The end-Guadalupian(or pre-Lopingian) biological crisis occurred during the late Capitanian, when faunal changeovers of different fossil groups had different paces, but generally experienced a relatively long time from the Jinogondolella altudensis Zone until the earliest Wuchiapingian. The end-Permian mass extinction was a catastrophic event that is best constrained at the Meishan section, which occurred at 251.941±0.037 Ma and persisted no more than 61±48 kyr. After the major pulse at Bed 25, the extinction patterns are displayed differently in different sections. The global end-Guadalupian regression is manifested between the conodont Jinogondolella xuanhanensis and Clarkina dukouensis zones and the endChanghsingian transgression began in the Hindeodus changxingensis-Clarkina zhejiangensis Zone. The Permian Period is also characterized by strong faunal provincialism in general, which resulted in difficulties in inter-continental and inter-regional correlation of both marine and terrestrial systems. 相似文献
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利用四川省地震局的数据资源,进行计算机扫描,研究中短期尤其是临震异常信息,发现大地震前所记录到的固体潮观测逐时值曲线,与地磁日变形态曲线,多发生了一定异常变化。这一发现捕卟未来大地震前兆临震信息判别提供重要参考。文章最后为捕捉临震异常信息,提出需要采取的措施及建议。 相似文献
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