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Reflection attributes of paragneiss in the upper crust

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Science China Earth Sciences 2008年第1期51卷 1-10页

作者： yang wencai XU ZhiQin YU ChangQing Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

The integrated study of the geological and seismic reflection data from the drilling area of CCSD has discovered that the density and the P-wave velocity of orthogneiss are almost the same as that of the paragneiss in the area; but the orthogneiss and the paragneiss hold different reflection attributes. The strong seismic reflector packes coinciding spatially with the paragneiss suites have implied that the paragneiss buried in the metamorphic crust itself can cause bone-like seismic reflector sets. The P-wave velocity of paragneiss shows little apparent difference with that of the orthogneiss; but its transverse wave velocity is lower, with the Vp/Vs ratios being high. The paragneiss has partially inherited the layering structures and textures of the protolithe of sedimentary rocks, hence shows strong heterogeneity and anisotropy, that is why the paragneiss are able to produce the bone-like reflectors in the upper crust. The low transverse wave velocity of paragneiss often means weak shear resistance, which will further cause cracks or fractures in the rock, consequentially increase its porosity and permeability during tectonic movements, and form the paragneiss reservoirs of low-permeability zones for gases uplifted from the deeper crust. Because the paragneiss in the crustal metamorphic basement can cause the seismic reflectors, seismic reflection sections are able to provide information about the paragneiss under certain prerequisites.

关键词： seismic reflection method metamorphic basement paragneiss crust reflectors

Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

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Science China Earth Sciences 2005年第5期48卷 585-600页

作者： yang wencai 1 , yang Wuyang 1 , JIN Zhenmin 2 & CHENG Zhenyan 1 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2. China University of Geosciences, Wuhan 430074, China Chinese Academy of Geological Sciences Institute of Geology Beijing China China University of Geosciences Wuhan China

Calibration of seismic reflectors appearing in the crust of the Chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 11 km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu China, calibration of reflectors, lithospheric fabrics.

Separate Analysis of Remote Sensing Information of Structures of Different Geological Periods and Quantitative Study of Corresponding Tectonic Stress Fields

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Acta Geologica Sinica(English Edition) 1997年第3期71卷 344-354页

作者： yang Wunian and Zhu Zhangsen Institute of Remote Sensing and GIS, Chengdu University of Technology,Chengdu, Sichuan Liu Xinzhu yang wencai

The structural feature shown on a remote sensing image is a synthetic result ofcombination of the deformations produced during the entire geological history of an ***, the respective tectonic stress field of each of the different stages in the complexdeformation of an area can be reconstructed in three steps: (1) geological structures formed atdifferent times are distinguished in remote sensing image interpretation; (2) structuraldeformation fields at different stages are determined by analyzing relationships betweenmicrostructures (joints and fractures) and the related structures (folds and faults); and (3)tectonic stress fields at different stages are respectively recovered through a study of the featuresof structural deformation fields in different periods. Circular structures and related circlular and radial joints are correlated in space to con-cealed structural rises. The authors propose a new method for establishing a natural model ofthe concealed structural rises and calculating the tectonic stress field by using quantitative dataof the remote sensing information of circular structures and related linear structures.

关键词： separate analysis of the remote sensing information field circular structure linear structure stress field quantitative analysis 3—dimensional colour structural block diagram

Heat Dissipation and Entropy Variation of the Earth System

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Continental Dynamics 2000年第1期 76-78页

作者： yang wencai Institute of Geology, CAGS, Beijing, 100037

An approximate model for heat dissipation and entropy variation of the Earth is given under the consideration of continental accretion and plate tectonics. The model shows that throughout geological history the flourishing of life occurred during stable entropy periods, while the extinction of complex life occurred during the periods of rapid entropy increasing.

关键词： dissipation entropy approximate model

Seismic multi-arch structures in East China

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Science China Earth Sciences 2006年第2期49卷 133-146页

作者： yang wencai1 & CHEN Zhide2 1.Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2.Daqing Institute of Petroleum Exploration and Production, Daqing 163712, China Institute of Geology Chinese Academy of Geological Sciences Beijing China Daqing Institute of Petroleum Exploration and Production Daqing China

In previous papers (wencai, 2002, 2003), the author has analyzed the deep seismic reflection profiles along some of the Mesozoic plutons in East China, and has pointed out that the crustal structures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure. This paper will continue to show main characteristics of the seismic multi-arch structures and discuss their relationship with mantle-origin magmatism and the lithospheric thinning process. Calibration of seismic reflectors in Chinese continental drilling sites shows that small-scale arch-like reflectors can be generated by fractured eclogites or other plutons, they do not belong to the multi-arch structure specially discussed in the paper. The multi-arch structure is char-acterized by several arch-like reflectors distributed in both the upper and lower crust with granitoid plutons or stocks exposed on the surface, which do not have obvious negative Europium anomalies. Based on the distribution pattern of arch reflectors, the multi-arch magmatic structures can be divided into three main types, namely the simple vertical combination type, the spread arch magmatic struc-ture and the arch-bouquet structure. All of them correlate to mantle-origin magmatism, but occur in different places. The spread arch magmatic structures occur within a Mesozoic/Cenozoic rift zone with very thin and hot lithosphere. The vertical combination type of the multi-arch structures occurred near the rift zones where lithosphere was thin and hot. The arch-bouquet magmatic structures occur far from the rift zones where the lithosphere is not hot. The continental rifting acted as the late episode of the lithospheric thinning process seeing that the rift zones usually coincide with the thinnest parts of the lithosphere in East China. In different locations within the lithospheric thinning areas, mantle-origin magmatic activities have different characteristics, which might generate different

关键词： deep seismic reflection, multi-arch structure, eclogite bodies, mantle-origin magmatism, East China.

Allelic Tests and Sequence Analysis of Three Genes for Resistance to Xanthomonas perforans Race T3 in Tomato

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Horticultural Plant Journal 2015年第1期1卷 41-47页

作者： ZHAO Baimei CAO Haipeng DUAN Junjie yang wencai Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops Department of Vegetable ScienceChina Agricultural University

Three crosses,Hawaii7981×PI128216,Hawaii7981×LA1589,and PI128216×LA1589,were made to develop F_2 populations for testing allelism among three genes Xv3,Rx4,and Rx_(LA1589) conferring resistance to bacterial spot caused by Xanthomonas perforans race T3 in tomato. Each population consisted of 535–1 655 individuals. An infiltration method was used to inoculate the leaves of the parental and F_2 plants as well as the susceptible control OH88119 for detecting hypersensitive resistance(HR). The results showed that all the tomato plants except OH88119 had HR to race T3,indicating that Xv3,Rx4,and Rx_(LA1589) were allelic genes. Genomic DNA fragments of the Rx4 alleles from Hawaii7981,PI128216,and LA1589 were amplified using gene-specific primers and sequenced. No sequence variation was observed in the coding region of Rx4 in the three resistant lines. Based on the published map positions of these loci as well as the allelic tests and sequence data obtained in this study,we speculated that Xv3,Rx4,and Rx_(LA1589) were the same gene. The results will provide useful information for understanding the mechanism of resistance to race T3 and developing resistant tomato varieties.

关键词： tomato tomato bacterial spot race T3 hypersensitive resistance gene allelic test

PAP3 Regulates Stamen but Not Petal Development in Capsicum annuum L.

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Horticultural Plant Journal 2016年第2期2卷 91-96页

作者： MA Ning LIU Chen yang wencai SHEN Huolin Beijing Key Laboratory of Facilities Vegetables Growth Regulation College of Horticulture China Agricultural University

Pepper flowers are hermaphroditic; the plant's male sterility trait is characterized by its inability to produce pollen grains. In the ABC model of flower development, B-function genes play roles in petal and stamen development in the angiosperm. In this study, a B-class gene designated as PAP3 (Gen Bank accession no. HM104635) was isolated in pepper. The gene encoded 226 amino acids and shared high similarity with the MADS-box protein family, with a conservative MADS domain and semiconservative K domain. Furthermore, the expression of PAP3 was abundant only in petals and anthers but not in leaves. A functional study employing virus-induced gene silencing(VIGS) showed that knockdown of PAP3 led to the shriveling of pollen grains and male sterility; however, it did not affect petal development. These results suggest an essential role for PAP3 in the development of the pepper stamen and in contributing to the variation of floral traits.

关键词： Capsicum annuum PAP3 MADS-box protein VIGS flower development male sterility

Crustal Structure and Development of the Dabie UHPM Terrane in East-Central China

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Continental Dynamics 1998年第Z1期 88-97页

作者： yang wencai and CHEN Zhenyan (Institute of Geology, CAGS, Beijing 100037)

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｎｃｅｔｈｅｄｉｓｃｏｖｅｒｙｏｆｃｏｅｓｉｔｅａｎｄｍｉｃｒｏｄｉａｍｏｎｄｉｎｃｌｕｓｉｏｎｓｉｎｔｈｅＤａｂｉｅＳｕｌｕａｒｅａ，ｔｈｅｕｌｔｒａｈｉｇｈｐｒｅｓｓｕｒｅｍ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｎｃｅｔｈｅｄｉｓｃｏｖｅｒｙｏｆｃｏｅｓｉｔｅａｎｄｍｉｃｒｏｄｉａｍｏｎｄｉｎｃｌｕｓｉｏｎｓｉｎｔｈｅＤａｂｉｅＳｕｌｕａｒｅａ，ｔｈｅｕｌｔｒａｈｉｇｈｐｒｅｓｓｕｒｅｍｅｔａｍｏｒｐｈｉｃ（ＵＨＰＭ）ｂ...

关键词： crustal structure seismic reflection collisional pattern Dabie

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从扩充的威尔逊循回看中国大陆演化轨迹

地质论评 2015年第2期61卷 237-244页

作者：杨文采 "大地构造与动力学"国家重点实验室中国地质科学院地质研究所北京100037

全球对比同类大地构造单元的壳幔结构,根据壳幔结构的差异和大地构造作用发生的时代把它们按演化阶段排序,可以找寻这类大地构造单元岩石圈演化的规律性。笔者在文中根据全球地学界实施的COCORP、BIRPS、DEKORP、LITHOPROBE、ICDP、ECOR... 详细信息

全球对比同类大地构造单元的壳幔结构,根据壳幔结构的差异和大地构造作用发生的时代把它们按演化阶段排序,可以找寻这类大地构造单元岩石圈演化的规律性。笔者在文中根据全球地学界实施的COCORP、BIRPS、DEKORP、LITHOPROBE、ICDP、ECORS和SINOPROBE等计划取得的成果,扩充了板块构造学中的威尔逊循回,即把原先主要描述大洋板块起源、发展和封闭的威尔逊循回,扩展到同时包括大陆和大洋板块演化的大循回中去。文中概述了扩充的威尔逊循回的内容,除经典的威尔逊循回的组元之外,扩充的组元包括洋陆转换、大陆汇聚拼合和大陆裂解等,为大陆岩石圈生成和演化作用提供了细节。根据扩充的威尔逊循回的大陆岩石圈演化规律,可以对中国地质学家已经发展的大陆构造演化的序列进行进一步的阐释,使构造演化的序列的属性和轨迹更加准确清晰。从寒武纪古亚洲洋扩张和冈瓦纳大陆裂解,到新生代印度次大陆与亚欧大陆碰撞拼合,中国大陆的大地构造事件序列说明扩充的威尔逊循回的是大陆岩石圈演化轨迹的大概率规律。

关键词：板块构造扩展的威尔逊循回全球对比岩石圈演化大地构造作用中国大陆作用事件序列