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On the siltation of the middle Yangtze River

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Science china earth {2. 2004年第5期47卷 463-480页

作者： YIN Hongfu1, CHEN Guojin2. LI Chang抋n1 & WEI Yuan3 1. School of earth sciences,{2., wuhan 43.074,{4. 2. Hydrogeological Team, Hubei Bureau of Geology and Mineral Resources, Jingzhou 4.4.00,{4. 3. Geological Survey of Jiangxi Province, Nanchang 3302.1,{4. china Univ Geosci Sch Earth Sci Wuhan 430074 Peoples R China Hubei Bur Geol & Mineral Resources Hydrogeol Team Jinzhou 434100 Peoples R China Geol Survey Jiangxi Province Nanchang 3300201 Peoples R China

About 5.2.108 t/a of silts from the upper reach of the Yangtze River are transported through Yichang into the middle Yangtze River. The middle Yangtze itself and its tributaries yield ca. 0.8×108 t silts annually. Of this total 6×108 t/a input of silts, ca. 1.2.108 t/a are deposited within the river artery and lakes, while ca 4.83×108 t/a are at first transported into the lower reach through Datong, and then either deposited along the river and the Yangtze Delta, or output into the sea. Along the middle Yangtze River silting generally exceeds scouring, but the spatial and temporal distributions of scour-and-fill, as well as its distribution in the river valley transections, are uneven. Along the Yichang-Chenglingji and Jiujiang-Datong Segments of the middle Yangtze, scouring exceeds or equals silting. Silting mainly occurs along the Luoshan-wuhan-Huangshi Segments with wuhan as the pivotal point, as well as in the Dongting and Poyang Lakes. Even in these silting-dominated areas, there are times and parts of segments that scouring prevails. As to the transections, generally the river channel of main stream is scouring-dominated, forming V-shaped sections to a depth of 2.30 m or more, whereas the floodplains and bar islands are silting-dominated, forming wide and relatively high flats, which are often artificially transformed into protected embankments. Because the Jingjiang Levee separates the Jianghan Plain from Yangtze to the south, little has been deposited in that plain except a few sediments from the Han River—a tributary of the middle Yangtze. This factor plus the tectonic sag of that plain has made the altitude of plain surface several meters lower than that of the levee in most of the areas. Sil-tation along the Luoshan-wuhan-Huangshi Segments has resulted in the elevation of flood level in this and upstream segments. River channel scouring plus floodplain silting have caused the transections of the middle Yangtze valley typically with deep channel and height

关键词： the middle Yangtze, scour-and-fill, siltation, silt utilization.

SHRIMP zircon U-Pb age and significance of Early Paleozoic volcanic rocks in East Kunlun orogenic belt, Qinghai Province, china

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Science china earth {2. 2006年第1期49卷 88-96页

作者： ZHU Yunhai1, LIN Qixiang1, JIA Chunxing2.& WANG Guocan1 1.Faculty of earth Science, china university of geosciences,{2., china 2.Regional Geological Survey Academy of Qinghai, Xining 800003, china 1. Faculty of earth Science China University of Geosciences Wuhan 430074 China 2. Regional Geological Survey Academy of Qinghai Xining 800003 China

Early Paleozoic volcanic rocks in Nuomuhong area occurred as basalt slice and meta-volcanic slice. SHRIMP zircon U-Pb dating of the basalt slice and the meta-volcanic slice show that the age of the basalt slice is 4.9±5 Ma, and that of the meta-volcanic slice is 4.1± 6 Ma. These ages directly testify that there existed Early Paleozoic ocean-continent transform in East Kunlun, the basalt slice was formed in an extensional mid-ocean ridge setting and the meta-volcanic rock slice was formed in an extrusion subduction and collision setting. The inherited zircon age of 1734.Ma in volcanic rocks reflects that the base of East Kunlun may be Middle Proterozoic.

关键词： volcanic rocks, SHRIMP zircon U-Pb age, Early Paleozoic, East Kunlun orogenic belt.

Delineation of Potential Mineral Resources RegionBased on Geo-anomaly Unit

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Journal of earth Science 2000年第2期19卷 66-71页

作者： Chen Yongqing Faculty of earth Resources, china university of geosciences,{2. The Center for Development and Research, china Geological Survey, Beijing 100083 Liu Hongguang Faculty of earth Resources, china university of geosciences, wuhan 4

The geological anomaly unit method (GAUM) is a new way to delineate and evaluate ore finding targets in line with the “geological anomaly ore finding theory”. Comprehensive ore finding information from geological, geochemical and geophysical data is used for quantitative measurement of the “ore forming geological anomaly unit” in this paper. The main procedures are shown as follows: (1) The geo anomalous events associated with gold mineralization are analyzed in Tongshi gold field; (2. The zonation in the concentrated heavy minerals and the stream sediment elements of ore forming geo anomaly are studied in detail; (3) The deep geological structural framework is deduced by means of the synthetic geological interpretation of gravity and magnetic information; (4. The ore controlling geo anomalies and ore anomalies are chosen as the variables of the favorable ore forming indexes that can be used for the quantitative delineation and evaluation of the potential ore forming regions.

关键词： ore forming geo anomaly unit mineral resources areas comprehensive ore forming information favorable ore forming index Tongshi gold field western Shandong Province Eastern china.

Stratigraphic Succession,Source-Rock Distribution and Paleoclimatic Zone in Meso-Cenozoic Basins,Eastern china

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Journal of earth Science 1997年第1期16卷 11-15页

作者： Lu Zongsheng Huang Qisheng Faculty of earth sciences,{2., wuhan 43.074 Li SitianFaculty of earth Resources,{2., wuhan 43.074

?The unequal spacetime distribution of the source rocks resulted from the mutual superimposition of the biota evolution, basin type, and paleoclimatic change. The basin type is the most important in controlling the distribution of source rocks. The effect of the paleoclimate on the source rocks varied with different basins. In the rift basin, the source rocks were accumulated in the humid, semihumid and semiarid climates; however, in the flexural basin, only in the humid and semihumid climates. The biota features may control, to a great extent, the distribution pattern and the sourcerock quality. The abundance of the terrestrial flora and lacustrine phytoplankton was essential for the generation of the Meso-Cenozoic source rocks on a large scale.

关键词： petroleum source rock paleoclimatic zone Meso-Cenozoic basin eastern china.

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china earth {2. 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of Geodesy and earth’s Dynamics,Institute of Geodesy and Geophysics,Chinese Academy of sciences,{2. 4.0077,china 2.Graduate {4. of Chinese Academy of sciences,Beijing 10004.,china 3 Institute of Geophysics,Huazhong {4. of Science and Technology,{2. 43.074,china 1. State Key Laboratory of Geodesy and earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Geophysics Huazhong University of Science and Technology Wuhan 430074 China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4.cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2.09,which is significantly higher than the global sea level rise rate of 3.3±0.4.mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

Research on the method for retrieving soil moisture using thermal inertia model

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Science china earth {2. 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. Information College, South china Agricultural university, Guangzhou 5106{2., china 2. Graduate university of Chinese Academy of {{2., Beijing 1000{2., china 1. Information College South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Tectonic-Hydrocarbon Accumulation Analysis of Laoyemiao Region in Nanpu Sag,Bohai Bay Basin

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地学前缘 2009年第S1期16卷 154-155页

作者： Cuimei Zhang,Xiaofeng Liu,Jianye Ren Faculty of earth Resources,china {2. of geosciences({4.),{4. 43.074,china.

Nanpu sag lies in the northwest part of the Bohai bay *** structural zone is located in the northwest part of the sag,to the north bound by basin-bounding master fault-Xi’nanzhuang fault (XNZF).This paper aims to gai... 详细信息

关键词： tectonic-hydrocarbon accumulation analysis Laoyemiao region Nanpu sag

Location of Triassic Tectonic Suture Between Collided Sino-Korean and Yangtze Cratons in Dabie-Sulu Region, china

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Journal of earth Science 1999年第4期18卷 281-286页

作者： Suo Shutian Zhong Zengqiu You Zhendong(Faculty of earth sciences,{2., wuhan 43.074) Faculty of earth sciences China University of GeosciencesWuhan 430074

The regional extent and spatial distribution of ultrahigh pressure metamorphic(UHPM) and high pressure metamorphic (HPM) rocks, and the geometrical relationships of various petrotectonic units in the Dabie-Sulu region indicate that the Triassic collisional suture line between the Sino-Korean and Yangtze cratons is situated at the northern margin of the Dabie massif, that is,along the Balifan-Mozitan-Xiaotian fault in the Dabie region, and possibly is linked to the Wulian-Yantai fault in the Sulu region to tbe east. The suture line has been strongly modified duriug and subsequent to UHPM aud HPM events.

关键词： UHPM and HPM belts suture line Dabie massif Dabie-Sulu region

Permian and Triassic Sequence Stratigraphy and Sea Level Changes of Eastern Yangtze Platform

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Journal of earth Science 1999年第2期18卷 71-79页

作者： Tong Jinnan Yin Hongfu Zhang Kexin Faculty of earth sciences,{2., wuhan 43.074

The Permian and marine Triassic of eastern Yangtze platform, situated in eastern china, involve 19 orthosequences lasting about 2.7 Ma on average, which can be combined into five orthosequence sets ranging from 8 Ma to 12.Ma. Affected by the regional Dongwu and Indosinian movements, the sequence stratigraphic pattern and sea level changes in the Permian and Triassic of this region are distinctive and obviously different from most other regions in the world, but typical in the broad eastern Tethys and its neighboring areas. In this region not only did the continuous marine Permian and Triassic boundary sequences cause the orthosequence crossing the boundary belonging to type Ⅱ sequence but also the mesosequence including these stratigraphic intervals had its basal boundary in the upper Longlinian (Artinskian) (ca. 2.8 Ma), that is, the traditional Carboniferous and Permian boundary, and its top boundary moved from the Permian and Triassic boundary upward into the Anisian of Middle Triassic.

关键词： Permian and Triassic sequence stratigraphy sea level change eastern Yangtze platform.