检索结果-南通市图书馆

Two thin middle-crust low-velocity zones imaged in the Chuan-Dian region of southeastern Tibetan Plateau and their tectonic implications

引用

Science China Earth Sciences 2024年第5期67卷 1675-1686页

作者： Long LI Xin WANG Guangbing HOU Yuan LING Yinshuang AI Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China

intracrustal low-velocity zones(LVZs)indicate a mechanically weak crust and are widely observed in the southeast margin of the Tibetan ***,their spatial distributions and formation mechanisms remain *** investigate their distribution and detailed morphology of the LVZs in the southeastern Tibetan Plateau,here we used teleseismic events and continuous waveform data recorded by 40 broadband seismic stations newly deployed in the Sichuan-Yunnan region from December 2018 to October 2020.A total of 12,924 high-quality P-wave receiver functions and 5–40 s fundamental Rayleigh surface wave phase velocity dispersion curves from ambient noise cross-correlation functions were *** Swave velocity model at a depth interval of 0–100 km in the study area was inverted by using the trans-dimensional Markov chain Monte Carlo strategy to jointly invert the complementary data of the receiver function waveform and Rayleigh surface wave phase velocity *** results show that there are two separate LVZs(~3.5 km/s)surrounding the rigid Daliangshan subblock at crustal depths of approximately 30–40 km,providing new constraints on the geometry of the LVZs in our study *** two LVZs obtained in this study may represent the middle crustal flow channels,through which the material in the center of the Tibetan Plateau extrudes to its southeast *** by the rigid Sichuan Basin and the spindle-like Daliangshan subblock,the material continues to flow southward through the mechanically weak middle crustal channels surrounding the Daliangshan *** addition,the existence of thin LVZs in the middle crust plays an important role in understanding the decoupling between the upper and lower crust in the study *** also provides new constraint on the complex tectonic deformation process of the southeastern margin of the Tibetan Plateau caused by the collision and compression of the Indian and the Eurasian plates.

关键词： Southeastern Tibetan Plateau Joint inversion intracrustal low-velocity zone Mid-crustal channel flow

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Partial Melting and Its Implications for Understanding the Seismic velocity Structure within the Southern Tibetan Crust

引用

Acta Geologica Sinica(English Edition) 2003年第1期77卷 64-71页

作者： YANG Xiaosong, MA Jin, JIN Zhenmin, GAO Shan and MA Shengli Geology Institute, China Seismological Bureau, Beijing 100029 Laboratory of Tectonophysics, China Seismological Bureau, Beijing 100029 Faculty of Earth Sciences, China University of Geosciences, Wuhan, Hubei 430074 China Seismol Bur Inst Geol Beijing 100029 Peoples R China China Seismol Bur Lab Tectonophys Beijing 100029 Peoples R China China Univ Geosci Fac Earth Sci Wuhan 430074 Hubei Peoples R China

In order to constrain the crustal wave velocity structure in the southernTibetan crust and provide insight into the contribution of crustal composition, geothermal gradientand partial melting to the velocity structure, which is characterized by low average crustalvelocities and widespread presence of low-velocity zone(s), the authors model the crustal velocityand density as functions of depth corresponding to various heat flow values in light of velocitymeasurements at high temperature and high pressure. The modeled velocity and density are regarded ascomparison standards. The comparison of the standards with seismic observations in southern Tibetimplies that the predominantly felsic composition at high heat flow cannot explain the observedvelocity structure there. Hence, the authors are in favor of attributing low average crustalvelocities and low-velocity zone(s) observed in southern Tibet mainly to partial melting. Modelingbased on the experimental results suggests that a melting percentage of 7-12 could account for thelow-velocity zone(s).

关键词： partial melting intracrustal low-velocity zone high-pressure andhigh-temperature experiments Tibetan plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：