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Carbon-Isotope Excursions Recorded in the Cambrian System,South China:Implications for Mass Extinctions and Sea-Level Fluctuations

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Journal of Earth Science 2018年第3期29卷 479-491页

作者： Jingxun Zuo Shanchi Peng yuping qi Xuejian Zhu Gabriella Bagnoli Huaibin Fang Henan Institute of Geological Survey Zhengzhou 450001China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing 210008China Department of Earth Sciences University of PisaVia S.Maria53Pisa 56126Italy

Cambrian carbonates with abundant fossils of agnostoid trilobites deposited on the southern slope （Jiangnan slope belt） of the Yangtze Platform and in the Jiangnan deepwater basin are well exposed in the Wangeun Section of western Hunan, South China, and in the Duibian A Section of western Zhejiang, southeastern China, respectively. To better understand the response of carbonisotope excursions to depositional environment changes, mass extinctions and eustatic events, we collected 530 carbonate samples in fresh roadcut exposures of the two measured sections for analysis of carbon and oxygen isotopic compositions. Data of δ^13C from the Wangcun Section, western Hunan, South China, demonstrate that the Cambrian carbon-isotope profile includes three remarkable positive excursions CPEwc-1, 2, 3 in the Upper Series 2, in the Lower and in the Middle Furongian Series. Three distinctive negative excursions CNEwc,-1, 2, 3 were separately tested in the Lower Terreneuvian Series, Lower Series 3 and in the Upper Furongian Series. Similarly, in the corresponding horizons in the Duibian A Section, Zhejiang Province, southeastern China, three positive excursions CPEdb-1, 2, 3 and three negative excursions CNEdb-1, 2, 3 also have been discovered. We interpret these significant carbon-isotope excursions as being associated with enhanced biogenic prodnctivity, mass extinctions and eustatic events.

关键词： carbon-isotope excursion mass extinction sea-level change Cambrian South China.

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Geometry and tectonic deformation of the seismogenic structure for the 8 August 2017 M_S 7.0 Jiuzhaigou earthquake sequence,northern Sichuan, China

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Earth and Planetary Physics 2019年第3期3卷 253-267页

作者： Feng Long GuiXi Yi SiWei Wang yuping qi Min Zhao Sichuan Earthquake Agency Sichuan Seistech Corporation Ltd.

To reveal the geometry of the seismogenic structure of the Aug. 8, 2017 M_S 7.0 Jiuzhaigou earthquake in northern Sichuan,data from the regional seismic network from the time of the main event to Oct. 31, 2017 were used to relocate the earthquake sequence by the tomoDD program, and the focal mechanism solutions and centroid depths of the M_L ≥ 3.5 events in the sequence were determined using the CAP waveform inversion method. Further, the segmental tectonic deformation characteristics of the seismogenic faults were analyzed preliminarily by using strain rosettes and areal strains(As). The results indicate:(1) The relocated M_S 7.0 Jiuzhaigou earthquake sequence displays a narrow ～ 38 km long NNW-SSE-trending zone between the NW-striking Tazang Fault and the nearly NSstriking Minjiang Fault, two branches of the East Kunlun Fault Zone. The spatial distribution of the sequence is narrow and deep for the southern segment, and relatively wide and shallow for the northern segment. The initial rupture depth of the mainshock is 12.5 km, the dominant depth range of the aftershock sequence is between 0 and 10 km with an average depth of 6.7 km. The mainshock epicenter is located in the middle of the aftershock region, showing a bilateral rupture behavior. The centroid depths of 32 M_L ≥ 3.5 events range from 3 to 12 km with a mean of about 7.3 km, consistent with the predominant focal depth of the whole sequence.(2) The geometric structure of the seismogenic fault on the southern section of the aftershock area(south of the mainshock) is relatively simple, with overall strike of ～150° and dip angle ～75°, but the dip angle and dip-orientation exhibit some variation along the segment. The seismogenic structure on the northern segment is more complicated; several faults, including the Minjiang Fault, may be responsible for the aftershock activities. The overall strike of this section is ～159° and dip angle is ～59°, illustrating a certain clockwise rotation and a smaller dip angle

关键词： MS 7.0 Jiuzhaigou earthquake sequence relocation focal mechanism seismogenic structure geometry tectonic deformation

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Three dimensional velocity structure and accurate earthquake location in Changning–Gongxian area of southeast Sichuan

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Earth and Planetary Physics 2020年第2期4卷 163-177页

作者： Feng Long ZhiWei Zhang yuping qi MingJian Liang Xiang Ruan WeiWei Wu GuoMao Jiang LongQuan Zhou Seismological Bureau of Sichuan Province Chengdu 610041China College of Geophysics Chengdu University of TechnologyChengdu 610059China Emergency Administration of Yibin City Yibin Sichuan 644000China China Earthquake Networks Center Beijing 100045China

In order to understand the crustal structure and tectonic background of the Changning–Gongxiang area, southeastern Sichuan Province, where a series of moderate-to-strong earthquakes occurred in recent years, we utilized the seismic phase data both from a local dense array and from the regional seismic networks;we used the tomoDD program to invert for the high-resolution three-dimensional velocity structure within the depth range of 0–10 km and for accurate hypocentral locations in this area. We analyzed the seismogenic structures for the events of Xingwen M5.7 in 2018 and Gongxian M5.3 and Changning M6.0 in 2019. The results show that:(1) widespread lateral inhomogeneity exists in the velocity structure of the study area, and the location of the velocity anomaly is largely consistent with known structures. In the range of distinguishable depth, the inhomogeneity decreases with increasing depth, and the velocity structure anomalies in some areas are continuous in depth;(2) earthquakes occurred in clusters, showing the characteristics of zonal folding trends in the NW-SE and NE-SW directions;the focal depth in the area is generally shallow in both the sedimentary cap and the crystalline basement. The seismogenic structures of small earthquake clusters are different in size and occurrence in different sections, and the clusters occurred mostly in regions with high P-or S-wave velocities;(3) synthesis of a variety of data suggests that the seismogenic structures of the Xingwen M5.7 and Changning M6.0 earthquakes are associated with slip faults that trend NW-SE in, respectively, the south wing and the axis of the Changning–Shuanghe anticline, while that of the Gongxian M5.3 earthquake is associated with thrust faults that trend N-S in the Jianwu syncline region. The dynamic sources of the three earthquakes are all from the SE pushing of the qinghai–Tibet block on the Sichuan basin;(4) the risk of future strong earthquakes in this area must be reevaluated in light of the

关键词： southeastern Sichuan Sichuan Basin three-dimensional velocity structure earthquake precise location

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A Potential Global Standard Stratotype-Section and Point of the Moscovian Stage(Carboniferous)

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 366-372页

作者： WANG Xiangdong qi yuping Lance LAMBERT WANG Zhihao WANG Yue HU Keyi LIN Wei CHEN Bo State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontologythe Chinese Academy of Sciences Nanjing Jiangsu 210008 China Department of Geological Sciences University of Texas at San Antonio San Antonio Texas 78249-0663 USA

Conodonts and fusulinids are the two most widely used biotic groups for subdividing and correlating Bashkirian and Moscovian strata. The definition of the base of the Global Moscovian Stage is undecided because there are many disagreements among existing boundary definition proposals,each of which has disadvantages. Declinognathodus donetzianus is easily recognized but somewhat limited in its paleogeographic distribution. Idiognathoides postsulcatus is slightly more widespread, but it is less easily identified and its occurrences may be diachronous from region to region. Diplognathodus ellesmerensis is easily recognized and even more widespread, but it is usually rare and its ancestry is not adequately known. The Naqing Section of South Guizhou, South China contains diverse conodont evolutionary lineages among different taxa, including Idiognathoides, Idiognathodus, Diplognathodus,Neognathodus, Gondolella and Mesogondolella. There are numerous transitional forms in almost every lineage of the Naqing section, which shows that the prospects for South China to play a critical role in determining the basal Moscovian Stage definition are good.

关键词： Bashkirian-Moscovian Boundary Global Standard Stratotype-Section and Point conodont fusulinid the Naqing Section of South Guizhou China

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Carboniferous integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 135-153页

作者： Xiangdong WANG Keyi HU Wenkun qiE qingyi SHENG Bo CHEN Wei LIN Le YAO qiulai WANG yuping qi Jitao CHEN Zhuoting LIAO Junjun SONG CAS Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Center for Research and Education on Biological Evolution and Environment Nanjing University Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences

The Carboniferous period lasted about 60 Myr, from ～358.9 Ma to ～298.9 Ma. According to the International Commission on Stratigraphy, the Carboniferous System is subdivided into two subsystems, i.e., Mississippian and Pennsylvanian, including 6 series and 7 stages. The Global Stratotype Sections and Points(GSSPs) of three stages have been ratified, the Tournaisian, Visean, and Bashkirian stages. The GSSPs of the remaining four stages(i.e., the Serpukhovian, Moscovian,Kasimovian, and Gzhelian) have not been ratified so far. This paper outlines Carboniferous stratigraphic subdivision and correlation on the basis of detailed biostratigraphy mainly from South China, and summarizes the Carboniferous chronostratigraphic framework of China. High-resolution biostratigraphic study reveals 37 conodont zones, 24 foraminiferal(including fusulinid) zones, 13 ammonoid zones, 10 brachiopod zones, and 10 rugose coral zones in the Carboniferous of China. The biostratigraphic framework based on these biozones warrants the precise correlation of regional stratigraphy of China(including2 subsystems, 4 series, and 8 stages) to that of the other regions globally. Meanwhile, the Carboniferous chemo-, sequence-,cyclo-, and event-stratigraphy of China have been intensively studied and can also be correlated worldwide. Future studies on the Carboniferous in China should focus on(1) the correlation between shallow-and deep-water facies and between marine and continental facies,(2) high-resolution astronomical cyclostratigraphy, and(3) paleoenvironment and paleoclimate analysis based on geochemical proxies such as strontium and oxygen isotopes, as well as stomatal indices of fossil plants.

关键词： Carboniferous Chronostratigraphy Biostratigraphy Chemostratigraphy Event stratigraphy Stratotype Stratigraphic correlation

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EFFECT OF CROSS-LINKING ON THE EXCESS ENTHALPY RELAXATION OF EPOXY

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Chinese Journal of Polymer Science 1987年第1期5卷 1-6页

作者：陈雨萍漆宗能 Institute of Chemistry Academia Sinica Beijing

A method of comparative DSC technique is proposed for excess enthalpy relaxation study. The essential of the comparative DSC technique consists of comparing the enthalpy relaxation behavior of an aged sample with a quenched sample as reference. The accuracy of comparison is improved because of simultaneous measuring of the sample and reference which makes noise of the apparatus subtractive. This technique has been applied to studying the influence of crosslinking on the enthalpy relaxation behavior of epoxy resins. The effect of crosslinking on the kinetics of enthalpy relaxation of epoxy resins is discussed.

关键词： Epoxy DSC Physical aging Excess enthalpy relaxation

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联合概率法在合并相邻台网地震目录中的应用:以2014年鲁甸序列为例

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地球物理学报 2018年第7期61卷 2815-2827页

作者：龙锋蒋长胜祁玉萍刘自凤傅莺四川省地震局成都610059 中国地震局地球物理研究所北京100081 云南省地震局昆明650091

中国目前实行的区域地震台网独立运行机制,使得在相邻不同台网的交界地区可能存在多个版本的地震目录和震相观测报告,影响了地震活动性分析与研究.为此,本文提出了一种基于联合概率的方法,可标明两个或多个相邻台网目录中相同的事件,合... 详细信息

中国目前实行的区域地震台网独立运行机制,使得在相邻不同台网的交界地区可能存在多个版本的地震目录和震相观测报告,影响了地震活动性分析与研究.为此,本文提出了一种基于联合概率的方法,可标明两个或多个相邻台网目录中相同的事件,合并它们的震相数据开展重新定位,并重构不同台网交界地区的统一地震目录.该方法的思路与分析步骤是:首先,计算获得不同台网之间具有最小发震时刻差异的两两地震的时空强差异分布,查找并剔除独立地震,计算事件合并的联合概率;其次,基于联合概率分析合并不同台网的地震目录和震相观测报告,对合并事件进行重新定位和定位误差分析,并基于G-R关系检验重构目录的完整性.本文以2014年鲁甸地震序列为例的初步应用结果显示,震相合并之后的地震定位精度相比之前单个台网的结果,特别是相比四川台网的目录,定位精度提高非常显著,合并后的目录与之前相对完整的云南目录接近,但相比由两个台网目录简单拼凑而成的目录更加准确.此外,研究还发现在目录合并过程中,对于4级以上的中强震,应选择MS而不是以ML震级标度;震相合并后被复用台站记录的到时信息可用于检测不同台网间的震相拾取是否存在系统偏差.本文提出的方法使得在相邻不同台网的过渡区形成一个统一且尽可能准确可靠的地震目录成为可能.

关键词：地震目录联合概率鲁甸地震序列地震定位

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塔里木盆地古隆1井中上奥陶统牙形石生物地层界线研究

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地质科学 2011年第2期46卷 466-474页

作者：蔡习尧祁玉平钱一雄陈跃中国石油化工股份有限公司石油勘探开发研究院北京100083 中国科学院南京地质古生物研究所南京210008

塔中地区古隆1井中晚奥陶世处于台缘斜坡带,地层发育齐全,奥陶系划分为3统5组,自上而下为却尔却克组、恰尔巴克组、一间房组、鹰山组与蓬莱坝组。在恰尔巴克组及一间房组分别获得了Pygouds anserinus与***牙形石带,依此将中上奥陶统界... 详细信息

塔中地区古隆1井中晚奥陶世处于台缘斜坡带,地层发育齐全,奥陶系划分为3统5组,自上而下为却尔却克组、恰尔巴克组、一间房组、鹰山组与蓬莱坝组。在恰尔巴克组及一间房组分别获得了Pygouds anserinus与***牙形石带,依此将中上奥陶统界线划在5875 m,两统之间不存在任何地层缺失或不整合面。认为碳酸盐岩台地上的良里塔格组在古隆1井相变为191 m厚的泥岩夹灰质泥岩,在地震剖面显示为一套空白反射,横向较好追踪与对比;指出了恰尔巴克组与一间房组在平面展布上具有同步性,卡塔克隆起主体上缺失,仅分布在台地边缘低洼处或在斜坡带。

关键词：塔里木盆地古隆1井牙形石中上奥陶统

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试析自制教具在物理课堂中的应用

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现代基础教育研究 2016年第1期21卷 190-194页

作者：祁玉平上海外国语大学附属大境中学

物理是一门以实验为基础的科学,实验教具是物理实验教学中不可缺少的物质基础,是实现教学目标、提高教学质量的有效载体。文章介绍了如何开发、设计与运用自制教具,并从创设情境、体验探究、突破思维障碍、放大实验效果、激发创造力等... 详细信息

物理是一门以实验为基础的科学,实验教具是物理实验教学中不可缺少的物质基础,是实现教学目标、提高教学质量的有效载体。文章介绍了如何开发、设计与运用自制教具,并从创设情境、体验探究、突破思维障碍、放大实验效果、激发创造力等方面阐述了自制教具在创设高效课堂中的作用。

关键词：自制教具高效课堂激发情感建构知识解疑化难激发创造力

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一种基于模板匹配的震相关联和提取技术及其初步应用

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中国地震 2021年第2期37卷 368-378页

作者：龙锋祁玉萍赵敏芮雪莲四川省地震局成都610041

本文提出一套有别于常规模板匹配算法的流程,不仅能够提供被识别地震的时间、空间、强度信息,还可根据震相关联提取每个地震对应的震相到时资料供后续研究使用。该流程基本原理为:地震事件发生会使得震相记录在时间上趋于丛集,因此可利... 详细信息

本文提出一套有别于常规模板匹配算法的流程,不仅能够提供被识别地震的时间、空间、强度信息,还可根据震相关联提取每个地震对应的震相到时资料供后续研究使用。该流程基本原理为:地震事件发生会使得震相记录在时间上趋于丛集,因此可利用密度聚类方法对震相信息进行提取。具体实现步骤为:(1)对采用相同降采样和滤波处理的模板事件和连续波形进行互相关系数计算,挑选相关性超过阈值的到时信息形成离散时间序列;(2)对整个序列进行DBSCAN聚类分析并对每个聚类簇开展自洽性检验,获取单个地震的震相关联,进而提取震相到时;(3)通过去重复事件、震级测算与定位获得最终的结果。将该方法应用到龙门山断裂带南段地震空区,结果显示,2013年5月至2016年12月,35个模板共获得了93个确切的地震信息,是所使用模板的2.65倍,包含390条P波震相以及791条S波震相。绝大部分模板并没有识别出自身的重复/相似地震,而被识别出的地震是由少量模板匹配成功的,主要分布于双河和安顺附近。精定位结果显示,双石-大川断裂倾向NW,同时在安顺以西可能存在某条不知名的、浅部直立、深部倾向NW的"铲状"断裂,震源深度与芦山地震序列类似,存在自SW至NE变深的现象,可能反映了龙门山断裂带南段不同段落具有类似的构造特征。测试结果表明,本文设计的流程可提供包括震源参数和每个地震震相到时信息在内的完整震相报告,在模板识别领域可作为一套计算机自主处理的可行方案。

关键词：模板匹配 DBSCAN密度聚类自洽性检验震相提取地震空区

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