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Application of the Material Balance Method in Paleoelevation Recovery: A Case Study of the Longmen Mountains Foreland Basin on the Eastern Margin of the Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 598-609页

作者： YAN Zhaokun LI Yong LI Haibing DONG Shunli ZHAO Guohua LI Jingbo LI Fensheng YAN Liang ZHENG Lilong institute of sedimentray geology Chengdu University of Technology State Key Laboratory of Oil and Gas Reservoir geology and Exploitation (CDUT) State Key Laboratory of Continental Tectonics and Dynamics Institute of GeologyChinese Academy of Geological Sciences institute of geology and Geophysics Chinese Academy of Sciences

We applied the material balance principle of the denudation volume and sedimentary flux to study the denudation-accumulation system between the Longmen Mountains （Mts.） and the foreland basin. The amount of sediment in each sedimentation stage of the basin was estimated to obtain the denudation volume, erosion thickness and deposit thickness since the Late Triassic Epoch, to enable us to recover the paleoelevation of the provenance and the sedimentary area. The results show the following：（1） Since the Late Triassic Epoch, the elevation of the surface of the Longmen Mts. has uplifted from 0 m to 2751 m, and the crust of the Longmen Mts. has uplifted by 9.8 km. Approximately 72% of the materials introduced have been denuded from the mountains. （2） It is difficult to recover the paleoelevation of each stage of the Longmen Mts. foreland basin quantitatively by the present-day techniques and data. （3） The formation of the Longmen Mts. foreland basin consisted of three stages of thrust belt tectonic load and three stages of thrust belt erosional unload. During tectonic loading stages （Late Triassic Epoch, Late Jurassic-Early Cretaceous, Late Cretaceous-Miocene）, the average elevation of Longmen Mts. was lower （approximately 700-1700 m）. During erosional unloading stages （Early and Middle Jurassic, Middle Cretaceous and Jiaguan, Late Cenozoic）, the average elevation of Longmen Mts. was high at approximately 2000-2800m.

关键词： Longmen Mountains, foreland basin, material balance method, paleoelevation recovery the eastern margin of the Tibetan Plateau

An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi Shi Willie Soon ShiCan Qiu Department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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Science China Earth Sciences 2025年第1期 74-93页

作者： Ye YANG Steven A.BINNIE Sheng XU Cong-Qiang LIU Tibor J.DUNAI institute of Surface-Earth System Science School of Earth System Science Tianjin University institute of geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

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亚洲高山流域千年尺度地表剥蚀的制约因素

中国科学:地球科学 2025年第1期 75-94页

作者：杨业 Steven A.BINNIE 徐胜刘丛强 Tibor J.DUNAI 天津大学地球系统科学学院表层地球系统科学研究院 institute of geology and Mineralogy University of Cologne

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率... 详细信息

本研究利用前人1233个亚洲高山流域沉积物宇宙成因核素10Be数据统一计算了地表剥蚀速率,以约束构造、气候和地形如何影响和控制地表剥蚀过程.基于高程数据逐个像元的核素产率,使用蒙特卡洛模拟方法重新计算了10Be流域剥蚀速率.剥蚀速率变化范围从（7.4±0.7）mm ka-1（1σ;青藏高原内部）到（9,646744+777）mm ka-1（1σ;青藏高原南部）跨四个数量级,中位数为186mm ka-1.逐个像元计算的核素产率与传统模型使用质心坐标和平均高程计算的核素产率相比,后者96.6%核素产率被低估,其中高程差越大越被低估.两种方法计算的产率偏差可达40%,究其原因可能是流域高程分布不均和核素产率随海拔和纬度呈非线性变化.通过量化地表剥蚀速率与构造、气候、地形和岩性之间的相关性将有助于推演未知流域的剥蚀速率.从局部小尺度分析,亚热带台湾岛地区剥蚀速率可能主要受降水和新构造驱动的山体滑坡影响,而降水变化范围较窄的青藏高原东部的剥蚀速率主要受控于地形;冰川覆盖的高原地区剥蚀速率受冰川作用影响,如帕米尔、青藏高原内部和南部地区;青藏高原内部剥蚀速率较低是因为较低的降水和较高的侵蚀基准面,从而限制了河流的下切和地表起伏度演化.与局部小尺度强调单一主控因素不同,本研究对亚洲高山流域宏观大尺度进行量化分析发现:（1）地形指标（包括坡度、地形起伏度和河道陡峭指数）与剥蚀速率在千年尺度呈现一致的幂函数关系,而非简单线性;（2）剥蚀速率与气候（包括与海拔相关的降水、温度和植被覆盖度）和新构造活动（地震核密度分布）呈近似幂函数关系,为次要控制因素;（3）岩性与剥蚀速率没有明显的相关性,可能受限于流域复杂的岩性混合和低分辨率的可侵蚀指数数据.

关键词： 10Be剥蚀速率气候变化构造抬升地形梯度亚洲高山流域

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Magnetic mineral diagenesis in the post-glacial muddy sediments from the southeastern South Yellow Sea:Response to marine environmental changes

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Science China Earth Sciences 2005年第1期48卷 134-144页

作者： Jeong-Hae Chang Korean institute of geology

Core YSDP103 was retrieved in the muddy deposit under the cold eddy of the southeastern South Yellow Sea, and the uppermost 29.79 m core represents the muddy sediments formed in the shelf since about 13 ka BP. The lower part from 29.79 to 13.35 m, called Unit A2, was deposited during the period from the post-glacial transgression to the middle Holocene (at about 6 14C ka BP) when the rising sea level reached its maximum, while the upper part above 13.35 m (called Unit A1) was deposited in a cold eddy associated with the formation of the Yellow Sea Warm Current just after the peak of post-glacial sea level rise. Rock-magnetic properties of the uppermost 29.79 m core were investigated in detail. The experimental results indicate that the magnetic mineralogy of the core is dominated by magnetite, maghemite and hematite and that, except for the uppermost 2.35 m, the magnetic minerals were subject to reductive diagenesis leading to significant decline of magnetic mineral content and the proportion of low-coercivity component. More importantly, ferrimagnetic iron sulphide (greigite) is found in Unit A2 but absent in Unit A1, suggesting the control of marine environmental conditions on the magnetic mineral diagenesis. Magnetic parameters show abrupt changes across the boundary between Units A1and A2, which reflects a co-effect of environmental conditions and primary magnetic components of the sediments on the diagenesis. Alternating zones of high and low magnetic parameters are observed in Unit A2, which is presumably due to periodic changes of the concentration and/or grain size of magnetic minerals carried into the study area.

关键词： environmental magnetism, magnetic minerals, diagenesis, ferrimagnetic iron sulphide, South Yellow Sea.

Discovery and Significance of Malan Loess on the Piedmont Plain in Pinggu District, Beijing

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1565-1578页

作者： LU Lu ZHAO Yuanyi WANG Xiaoliang ZHAO Xitao YANG Zhenjing WANG Chengmin BI Zhiwei LU Wenhui institute of Mineral Resources Chinese Academy of Geological Sciences Beijing institute of geology Liaoning institute of geology and Mineral Resources institute of geology and Geophysics Chinese Academy of Sciences institute of Hydrogeology and Environmental geology Chinese Academy of Geological Sciences No.3 geology and Mineral Exploration institute of Gansu Provincial Bureau of geology and Mineral

The platforms on both sides of the Malangou River （a lateral ditch of the Qingshui River that is a tributary of the Yongding River） where Malan Village in Zhaitang Town of Mentougou District of Beijing is located are the place of China＇s typical section of the Quaternary Malan loess. During the investigation in the eastern suburbs of Beijing City, the authors not only clarified 5 grades of terraces on the Pinggu piedmont plain, but also found a clayey silt section mixed with a small amount of alluvial-diluvial gravel layers at a height of 15-25 m above the river level near a Fishpond in Xinli Village of Nandule Town. Results of the study of grain size of the section document that the loess mostly is silty soil （0.05--0.005 mm）, and that the grain size probability cumulative curves of the section are dominated by single-peak, coarse-grained segment I and coarse-grained segment II types, reflecting that its depositional environment is similar to eolian phase. Identification results of heavy minerals from the section show that their contents account for 0.01%-0.11%, averaging 0.04%. There are 24 kinds of heavy minerals, most of which are stable heavy minerals, and the clay minerals mostly are illite, which is consistent with the Malan loess on the Loess Plateau. The chemical composition data reflect that the source area of the loess is relatively arid. The six grade classification of sporopollen in the section further shows the subdivision of the history of alternating warm and humid phases in this geological period. The thermoluminescence dating results range from 21.0 ka to 59.2 ka, convincingly demonstrating that the section indeed consists of Malan loess. The above studies provide a new basis for overall understanding of the distribution of the Malan loess at the northeast margin of the North China Plain and its environment change in the Late Pleistocene.

关键词： eolian loess Malan loess formation environment Pinggu

Circulation background of climate patterns in the past millennium: Uncertainty analysis and re-reconstruction of ENSO-like state

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Science China Earth Sciences 2016年第6期59卷 1225-1241页

作者： TAN Ming Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences

The question of whether or not global warming has paused since more than ten years ago, namely ＂warming hia- tus＂, has attracted the attention of climate science community including the IPCC. Some authors have attributed the ＂warming hiatus＂ to the internal changes in the climate system, i.e., the recombination of ocean-atmosphere circulations. Therefore, it is necessary to propose higher requirements on reconstructing circulation background of climate change for the past millennium. However, the analyses of changes in atmospheric circulation over the last millennium as well as the conclusions of related re- gional climate patterns are so widely different and contradictory, bringing uncertainties to our understanding of regional even global climate change to a great extent. On the other hand, in the last 10 years the high-precision U/Th-dated stalagmite oxygen isotope ratio （δ^18O） sequences provided an accurate chronological frame for the paleoclimate study of the middle and late Pleistocene, in which all authors from China took the Chinese stalagmite δ^18O as the summer monsoon index without excep- tion. However, this point of view misleads the climate scientists into thinking that the stalagmite δ^18O can be as the proxy of precipitation amount. Nevertheless, it is well known that all of these records have a lot in common in the low frequency trend. However, most sequences cannot be calibrated by instrumental precipitation records, and thus the uncertainty of the climate research framework of China and even of the world has increased. Therefore, it is imperative for climatology to clarify the origin of contradiction and to reduce the uncertainty as early as possible. On the basis of analyzing the significance of stalag- mite ~180 in the monsoon regions of China, the author tries to propose a new circulation proxy in this paper： integrating the Chinese stalagmite oxygen isotope sequence to reconstruct the tropical Pacific sea surface temperature gradient, i.e., th

关键词： The past millennium ENSO Circulation background Climate pattern WPSH Stalagmite δ^18O Circulation recombination

On the Geotectonics of Southern China

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 111-130页

作者： Ren Jishun institute of geology,CAGS,Beijing Xie Guanglin institute of geology CAGS Beijing

The tectonic nature of southern China has changed again and again in the Phanerozoic. In the Caledoniancycle, there existed three tectonic units——the Yangtze paraplatform, Indosinian-South China Sea paraplatformand Caledonian South China fold belt, of which the last unit is not a collisional orogenic belt but ascissor-shaped aulacogen-type geosyncline opening towards Yunnan and Vietnam. In the Indosinian cycle,South China belonged to the Tethyan tectonic domain, and no abyssal oceanic basin existed there. Since theLate Triassic, especially in the Yanshanian orogenic stage, it became a component part of the peri-Pacificcontinental-margin activation belt of eastern Asia. No Alpinc-type orogenic belt occurs in the interior of thecontinent of southern China.

关键词： On the Geotectonics of Southern China

Combined Use of Multivariate Statistical Analysis and Hydrochemical Analysis for Groundwater Quality Evolution: A Case Study in North Chain Plain

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Journal of Earth Science 2014年第3期25卷 587-597页

作者： Rong Ma Jiansheng Shi Jichao Liu Chunlei Gui institute of Hydrogeology and Environmental geology

Understanding the controlling factor of groundwater quality can enhance promoting sustainable development of groundwater resources. To this end, multivariate statistical analysis（MA） and hydrochemical analysis were introduced in this work. The results indicate that the canonical discriminant function with 7 parameters was established using the discriminant analysis（DA） method, which can afford 100% correct assignation according to the 3 different clusters（good water（GW）, poor water（PW）, and very poor water（VPW）） obtained from cluster analysis（CA）. According to factor analysis（FA）, 8 factors were extracted from 25 hydrochemical elements and account for 80.897% of the total data variance, suggesting that groundwater with higher concentrations of sodium, calcium, magnesium, chloride, and sulfate in southeastern study area are mainly affected by the natural process; the higher level of arsenic and chromium in groundwater extracted from northwestern part of study area are derived by industrial activities; domestic and agriculture sewage have important contribution to copper, iron, iodine, and phosphate in the northern study area. Therefore, this work can help identify the main controlling factor of groundwater quality in North China plain so as to make better and more informed decisions about how to achieve groundwater resources sustainable development.

关键词： factor groundwater quality hydrochemical variable industrial activity multivariate statistical analysis.