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河南寒武系苗岭统微生物成因构造与后生动物扰动构造的交替发育
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作者 张彦欣 齐永安 +3 位作者 刘炳辰 代明月 王敏 李妲 《沉积学报》 CAS CSCD 北大核心 2023年第3期693-705,共13页
河南寒武系苗岭统发育了大量微生物成因构造(叠层石和凝块石)和后生动物扰动构造(遗迹化石)。登封馒头组三段下部以叠层石灰岩及含垂直潜穴鲕粒灰岩的交替发育为特征,常被风暴作用导致的凹凸不平界面所分隔,叠层石形成于中等能量的滩间... 河南寒武系苗岭统发育了大量微生物成因构造(叠层石和凝块石)和后生动物扰动构造(遗迹化石)。登封馒头组三段下部以叠层石灰岩及含垂直潜穴鲕粒灰岩的交替发育为特征,常被风暴作用导致的凹凸不平界面所分隔,叠层石形成于中等能量的滩间坪环境,而垂直潜穴发育于持续搅动的高能鲕粒滩环境;登封张夏组底部以凝块石灰岩和生物扰动构造灰岩的交替发育为特征,常以厚薄不均的泥岩层为分界面,二者均形成于正常浪基面之下的深水低能环境;卫辉崮山组以叠层石灰岩和生物扰动构造灰岩的交替发育为特征,二者以凹凸不平的界面或薄泥岩层相分隔,叠层石保存于中等能量的潮间坪沉积,而生物扰动构造则形成于低能的台地缓斜坡。当环境条件有利于微生物成席时(如清洁的水体、稳定的水动力条件和坚硬的底质),微生物成因沉积构造和微生物席底会大量发育。当环境条件不适合微生物席发育时(如浑浊的水体、交替变化的水动力条件和松软的底质),后生动物便开始在沉积物中掘穴,留下各类后生动物扰动构造和混合底。 展开更多
关键词 交替发育 寒武系 后生动物扰动构造 控制因素 微生物成因构造
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豫西P–Tr之交的微生物成因构造与后生动物扰动构造的耦合变化及生态学意义
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作者 郑伟 吴盼盼 +4 位作者 许欣 邢智峰 齐永安 刘云龙 李婉颖 《古生物学报》 CAS CSCD 北大核心 2022年第1期20-35,共16页
豫西登封、济源、宜阳、荥阳和巩义等地发育一套连续的二叠纪–三叠纪之交的陆相地层孙家沟组、刘家沟组和和尚沟组,保存着有环境和生物信息的微生物成因构造以及后生动物扰动构造,对二者的深入研究对二叠纪–三叠纪之交的陆相微生物与... 豫西登封、济源、宜阳、荥阳和巩义等地发育一套连续的二叠纪–三叠纪之交的陆相地层孙家沟组、刘家沟组和和尚沟组,保存着有环境和生物信息的微生物成因构造以及后生动物扰动构造,对二者的深入研究对二叠纪–三叠纪之交的陆相微生物与环境以及早三叠世的生物复苏有着重要的意义。研究区5个剖面保存了丰富的微生物成因构造和后生动物扰动构造,其中微生物成因构造有3大类、25小类,后生动物扰动构造有6属13种。这些构造在地层自下而上有一定的变化规律:微生物成因构造自孙家沟组中上部出现到刘家沟组顶部消失;后生动物扰动构造自刘家沟组上部出现,到和尚沟组上部逐渐增多,至中三叠世油房庄组基本达到灾变事件前的生物水平;二者仅在刘家沟组共生。本研究表明研究区微生物成因构造和后生动物扰动构造在整体上具有负相关性与耦合变化关系。 展开更多
关键词 二叠纪–三叠纪之交 微生物成因构造 后生动物扰动构造 耦合变化 豫西地区
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贵州“小春虫”:不排除“就是人类祖先”
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《科技中国》 2004年第8期67-67,共1页
关键词 动物化石 动物构造 “小春虫” “寒武纪大爆发”理论
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Geochemical characteristics of the fluid inclusions in the Gangxi Fault Belt, Huanghua Depression, Bohai Bay Basin, China 被引量:2
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作者 DING Wei-wei DAI Jin-xing +1 位作者 CHU Feng-you HAN Xi-qiu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第7期1011-1020,共10页
We studied the geochemical characteristics of the fluid inclusions in the Ordovician carbonates and the Oligocene Shahejie Formation sandstones from 15 wells in the Gangxi Fault Belt, Huanghua Depression. The fluid in... We studied the geochemical characteristics of the fluid inclusions in the Ordovician carbonates and the Oligocene Shahejie Formation sandstones from 15 wells in the Gangxi Fault Belt, Huanghua Depression. The fluid inclusions are all sec- ondary with gas/liquid ratio of 5%~10%. Base on Raman they are mainly composed of H2O, CO2 and CH4. The homogenization temperatures, combined with burial and geothermal history of the host rock, indicate that the fluid flows in the Shahejie Formation and the Ordovician carbonates were trapped in Neocene. Using a VG5400 mass spectrometer, the helium isotopic compositions were analyzed. Interpretation of results suggested a significant amount of mantle-derived helium mainly accumulating in the intersections of the NWW trending Xuzhuangzi and NE trending Gangxi faults. The maturity of hydrocarbon decreases from the intersection to the outside pointing out that the fluid related to the NWW trending Xuzhuangzi and NE trending Gangxi faults. These factors implied the fluid inclusions have a close relationship to the local tectonic setting. Gangxi Fault Belt experienced intensive Neo-tectonic activities in Cenozoic. Widespread faulted-depressions and strong volcanic eruptions manifested its tec- tonic status of extensional stress field. Mantle uplift caused the movement of magma that carried mantle-derived gases and deep heat flows, the deep-rooted tension faults provided the passages for the gases and heat flows to shallow crust levels. 展开更多
关键词 Gangxi Fault Belt Fluid inclusion Composition MANTLE-DERIVED Maturity Local tectonic setting
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Modifi cation of sleep architecture in an animal model of experimental cirrhosis 被引量:2
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作者 Anabel Jiménez-Anguiano Vanessa Díaz-Medina +5 位作者 Blanca Eugenia Farfán-Labonne Gloria Giono-Chiang David Kersenobich Mario García-Lorenzana Maria Concepción Gutiérrez-Ruiz Javier Velázquez-Moctezuma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第41期5176-5180,共5页
AIM: To analyze the polygraphic sleep patterns during cirrhosis progression in a rat model by repeated CCh administration. METHODS: Male Wistar rats received three weekly injections of CCl4 for 11 wk, and were analy... AIM: To analyze the polygraphic sleep patterns during cirrhosis progression in a rat model by repeated CCh administration. METHODS: Male Wistar rats received three weekly injections of CCl4 for 11 wk, and were analyzed before and during the induction of cirrhosis. Rats were im- planted with electrodes to record their sleep patterns. Polygraph recordings were made weekly over 11 wk for 8 h, during the light period. After a basal recording, rats received three weekly injections of CCl4. Histological confirmation of cirrhosis was performed after 11 wk. RESULTS: The results showed a progressive decrease in total wake time that reached statistical significance from the second week of treatment. In addition, there was an increase in total time of slow wave sleep (SWS)Ⅱ and rapid eye movement sleep (REM sleep) in most of the 11 wk. SWS I showed no significant variations. During the final weeks, a significant increase in REM sleep frequency was also observed. Histological analyses of the livers showed unequivocal signs of cirrhosis. CONCLUSION: These data suggest that hepatic failure produced by CCh administration is capable of modifying the sleep pattern even after only a few doses. 展开更多
关键词 Experimental cirrhosis SLEEP Rapid eye movement sleep CCI4 WAKEFULNESS
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Geometric Structure and Tectonic Activities of Wanquan Fault,Hebei Province
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作者 Zhou Jianglin You Huichuan +4 位作者 Zhou Yueling Shao Cuiru Yang Qiyan Li Jinjin Zhang Zhengyu 《Earthquake Research in China》 2013年第2期223-232,共10页
Based on detailed investigations and prospecting,this paper describes the geometrical characteristics and tectonic activities of Wanquan fault in northwest of Beijing. This fault strikes mainly northeast or northeast ... Based on detailed investigations and prospecting,this paper describes the geometrical characteristics and tectonic activities of Wanquan fault in northwest of Beijing. This fault strikes mainly northeast or northeast to north,dipping southeast,and extends over a length of 15km. It is a major geological and geomorphological margin,controlling the neotectonic movement in this region. On the southeast side of Wanquan fault are the Late Quaternary unconsolidated deposits,forming a basin or deposition; but on the other side is Mesozoic volcano debris,forming lower-mountains and hills. Wanquan fault is a mid- to-high-angle normal fault dipping southeast. This fault was more active in the Quaternary. Since the middle-late part of the alate Pleistocene,the average rate with vertical slip of a single fault is over 0. 03 ~ 0. 3mm /a,but the fault has multiple slipping surfaces,and a total rate with vertical slip will be estimated. 展开更多
关键词 Wanquan fault Geometric structure Tectonic activities
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A Study of the Middle Construction in English with Special Reference to Learner's Dictionaries 被引量:1
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作者 朱晓丽 陈国华 《Chinese Journal of Applied Linguistics》 2013年第4期407-421,518,共16页
Although the middle construction has attracted significant attention from syntacticians, its identity still remains controversial and it is not treated as a separate grammatical category in any English learner's dict... Although the middle construction has attracted significant attention from syntacticians, its identity still remains controversial and it is not treated as a separate grammatical category in any English learner's dictionary. This article, based on the data collected from three English learner's dictionaries, investigates the middle construction in terms of its syntactic and semantic properties and the constraints on its use. It shows that the three learner's dictionaries treat the middle construction in inconsistent and problematic manners. The middle use of a verb is not distinguished from either transitive verbs with an implicit object or intransitive verbs, which may hinder English learners' acquisition of the construction. The article proposes that middle verbs should be treated as a separate subcategory of verbs on a par with transitive and intransitive verbs so that learners will become more aware of them and learn to use them correctly. 展开更多
关键词 middle construction transitive verb intransitive verb learner's dictionary
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A thermal physical index to explore current tectonic activity with satellite remote sensing
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作者 CHEN ShunYun MA Jin +2 位作者 LIU PeiXun LIU LiQiang HU XiaoYan 《Science China Earth Sciences》 SCIE EI CAS 2012年第2期290-295,共6页
The use of satellite thermal infrared information is being developed as a method of exploring current tectonic activity. To realize real world application, an objective, stable and testable thermal physical index that... The use of satellite thermal infrared information is being developed as a method of exploring current tectonic activity. To realize real world application, an objective, stable and testable thermal physical index that is simultaneously related with tectonic activity must be established. From the viewpoint of the energy balance, the land surface is a boundary where energy is exchanged between outer space and the solid Earth. Regardless of how complex the influencing factors are, the land surface is mainly affected by the Sun, atmosphere and underground heat. In this paper, first, the relationships among land surface temperature, solar radiation, atmospheric temperature and thermal information from underground are obtained employing a mathematic physical method based on the equation of heat conduction and energy balance at the land surface. Second, a thermal physical index called the geothermal flux index (GFI), which can provide the activity state of underground heat, is constructed. Third, the theoretical basis of the thermal physical index is verified using stable annual variations in land surface temperature and solar radiation. Finally, combined with known crustal deformations derived using a global positioning system, the effectiveness of the GFI in extracting field tectonic motion is tested. The results indicate that the GFI is effective in providing information on current tectonic activity. 展开更多
关键词 current tectonic activity thermal physical index geothermal flux index remote sensing
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