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luminescence Chronology and Radiocarbon Reservoir Age Determination of Lacustrine Sediments from the Heihai Lake,NE Qinghai-Tibetan Plateau and Its Paleoclimate Implications

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Journal of Earth Science 2018年第3期29卷 695-706页

作者： Fuyuan An Zhongping Lai Xiangjun Liu Yixuan Wang Qiufang Chang baoliang lu Xiaoyun Yang Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Cryosphere Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China School of Earth Sciences China University of GeoscieneesWuhan 430074China Department of Geology Baylor UniversityWaco 76798USA

The accurately determining the lake ^14C reservoir age has a crucial significance for climatic reconstruction. In this study, the optically stimulated luminescence （OSL） dating method is employed to date samples from highstand lacustrine sediments, palaeoshoreline, fluvial terrace, and the alluvial fan of the Heihai Lake catchment. Accelerator mass spectrometry （AMS） 14C dating was also used to date fossil plants from highstand lacustrine sediments. Based on the calculations of linear regression with OSL against radiocarbon ages for same layers of two sections, the quantitative ^14C reservoir ages were estimated to lie between 3 353 and 3 464 yr during the 1.8 to 2.4 ka, which showed temporal variation. The sources of old carbon are the dissolution of carbonate bedrocks distributed along the Kunlun Mountain. The OSL ages of the different members of the hydatogen sedimentary system at Heihai Lake catchment indicate that a stronger hydrologic condition occurred from 3.0±0.2 to 1.8±0.2 ka, with a maximum lake level of 9 m higher than present. This humid stage was widely recorded in different sediments on the QTP and Chinese Loess Plateau （CLP）, indicating its broad synchronicity across the Asian Summer Monsoon region. The enhanced East Asian Summer Monsoon （EASM） and the Indian Summer Monsoon （ISM） resulted in the increase of moisture availability for the Heihai Lake area during this stage.

关键词： luminescence and radiocarbon dating 14C reservoir age Heihai Lake Qinghai-Tibetan Plateau(QTP) palaeoclimate implications.

Reassessment of the Distribution of Mantle CO_(2) in the Bohai Sea,China:The Perspective from the Source and Pathway System

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 337-347页

作者： TANG Huafeng GUO Tianchan WU Keqiang LIU Zilin XU Jianyong lu baoliang WANG Pujun Key Laboratory for Evolution of Past Life and Environment in Northeast Asia Jilin UniversityChangchun 130061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Natural ResourcesChangchun 130061China College of Earth Sciences Jilin UniversityChangchun 130061China CNOOC Research Institute Beijing 100028China Institute of Gravity and Magnetic Technology Chang’an UniversityXi’an 710054China

Research on the distribution of mantle CO_(2)should involve comprehensive analysis from CO_(2)source to *** crust-mantle pathway system is the key controlling factor of the distribution of mantle CO_(2),but has received little *** pathway system and controlling factors of CO_(2)distribution in the Bohai Sea are analyzed using data on fault styles and information on the mantle and *** relation between volcanic rocks and the distribution of mantle CO_(2)is reassessed using age data for CO_(2)*** distribution of mantle CO_(2)is controlled by uplift of the asthenosphere and upper mantle,magma conduits in the mantle and fault systems in the *** regions of the asthenosphere are accumulation areas for CO_(2).The area with uplift of the Moho exhibits accumulation of mantle CO_(2)at ***_(2)was mainly derived from vertical migration through the upper mantle and lower *** fault style in the upper crust controls the distance of horizontal migration and the locations of CO_(2)*** distribution of mantle CO_(2)and volcanic rocks are not the same,but both probably followed the same pathways *** CO_(2)in the Bohai Sea is concentrated in the Bozhong sag and the surrounding area,particularly in a trap that formed before 5.1 Ma and is connected to crustal faults(the Bozhang faults)and lithospheric faults(the Tanlu faults).

关键词： mantle CO_(2) source area pathway system fault Moho Bohai Sea

Characteristics of the Density and Magnetic Susceptibility of Rocks in Northern Borneo and their Constraints on the Lithologic Identification of the Mesozoic Rocks in the Southern South China Sea

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Acta Geologica Sinica(English Edition) 2021年第1期95卷 280-293页

作者： TANG Huafeng ZHAO Zhigang TIAN Zhiwen lu baoliang TANG Wu HE Kailun ZHU Chenxi WANG Pujun Key Laboratory of Mineral Resources Evaluation of Northeast Asia Ministry of Natural ResourcesChangchun 130061China CNOOC Research Institute Co. Ltd.Beijing 100028China College of Earth Sciences Jilin UniversityChangchun 130061China College of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

Based on the volume magnetic susceptibility and specific gravity measurements and mineral and lithologic identification results for 540 samples,the rock type,density,and magnetic susceptibility of rocks from northern Borneo were analyzed,and the applicability of gravity and magnetic data to the lithologic identification of the Mesozoic strata in the southern South China Sea was assessed *** results show that there are 3 types and 25 subtypes of rocks in northern Borneo,mainly intermediate-mafic igneous rocks and exogenous clastic sedimentary rocks,with small amounts of endogenous sedimentary rocks,felsic igneous rocks,and metamorphic *** rocks that are very strongly-strongly magnetic and have high-medium densities are mostly igneous rocks,tuffaceous sandstones,and their metamorphic *** rocks that are weakly magnetic-non-magnetic and have medium-very low densities are mostly conglomerates,sandstones,siltstones,mudstones,and *** rocks that are weakly magnetic-diamagnetic and have highmedium densities are mostly limestones and siliceous *** Cenozoic rocks are characterized by low densities and medium susceptibilities;the Mesozoic rocks are characterized by medium densities and medium-high susceptibilities;and the pre-Mesozoic rocks are characterized by high densities and low *** on these results and the distribution characteristics of the various rock types,it was found that the pre-Mesozoic rocks produce weak regional gravity anomalies;the Mesozoic sedimentary rocks produce negative regional gravity anomalies;whereas the Mesozoic igneous rocks produce positive regional gravity anomalies;and the Cenozoic igneous rocks produce positive regional gravity *** regional high magnetic anomalies in the southern part of the South China Sea originate from the Mesozoic mafic igneous rocks and their metamorphic equivalents;and the regional medium magnetic anomalies may be produced by the felsic igneous rocks and their

关键词： density magnetic susceptibility Mesozoic Borneo South China Sea

Texture and tectonic attribute of Cenozoic basin basement in the northern South China Sea

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Science China Earth Sciences 2014年第6期57卷 1199-1211页

作者： SUN XiaoMeng ZHANG XuQing ZHANG GongCheng lu baoliang YUE JunPei ZHANG Bin College of Earth Sciences Jilin University Research Institute China National Offshore Oil Corporation College of Geology Engineering and Geomatics Chang'an University Research Institute of Exploration & Development PetroChina Liaohe Oilfield Company

Based on the drilling data,the geological characteristics of the coast in South China,and the interpretation of the long seismic profiles covering the Pearl River Mouth Basin and southeastern Hainan Basin,the basin basement in the northern South China Sea is divided into four structural layers,namely,Pre-Sinian crystalline basement,Sinian-lower Paleozoic,upper Paleozoic,and Mesozoic structural *** paper discusses the distribution range and law and reveals the tectonic attribute of each structural *** Pre-Sinian crystalline basement is distributed in the northern South China Sea,which is linked to the Pre-Sinian crystalline basement of the Cathaysian Block and together they constitute a larger-scale continental block—the Cathaysian-northern South China Sea continental *** Sinian-lower Paleozoic structural layer is distributed in the northern South China Sea,which is the natural extension of the Caledonian fold belt in South China to the sea *** sediments are derived from southern East China Sea-Taiwan,Zhongsha-Xisha islands and Yunkai ancient uplifts,and some small basement *** Caledonian fold belt in the northern South China Sea is linked with that in South China and they constitute the wider fold *** upper Paleozoic structural layer is unevenly distributed in the northern South *** the basement of Beibu Gulf Basin and southwestern Taiwan Basin,the structural layer is composed of the stable epicontinental sea *** distribution areas in the Pearl River Mouth Basin and the southeastern Hainan Basin belong to ancient uplifts in the late Paleozoic,lacking the upper Paleozoic structural *** stratigraphic distribution and sedimentary environment in Middle-Late Jurassic to Cretaceous are characteristic of differentiation in the east and the *** marine,paralic deposit is well developed in the basin basement of southwestern Taiwan but the volcanic activity is not *** marine and paralic facies deposit is di

关键词： northern South China Sea basin basement structural layer tectonic attribute

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现代性政治及其限度——兼论印度学者帕萨·查特杰的现代政治观

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河南社会科学 2011年第3期19卷 69-72页

作者：陆保良浙江大学公共管理学院浙江杭州310028

现代性政治是政治现代化的应然目标与方向。现代性政治的兴起和成熟经历了一个曲折的发展历程。印度学者帕萨·查特杰描述了印度现代性政治的历史和现状,指出:如果把政治有限性置于西方现代性理论背景下进行审视,西方政治学的三大逻辑... 详细信息

现代性政治是政治现代化的应然目标与方向。现代性政治的兴起和成熟经历了一个曲折的发展历程。印度学者帕萨·查特杰描述了印度现代性政治的历史和现状,指出:如果把政治有限性置于西方现代性理论背景下进行审视,西方政治学的三大逻辑——公民社会、普遍意义的公民身份和民主政治很难适用于非西方国家。从现代性政治到现实的大众政治,从精英政治到底层政治,还有很长的路要走。

关键词：现代性政治底层研究公民社会民主政治

青藏高原东北缘岩石圈有效弹性厚度与地震分布关系

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地球物理学报 2024年第2期67卷 520-533页

作者：苏子旺鲁宝亮李柏森朱武长安大学地质工程与测绘学院西安710054 海洋油气勘探国家工程研究中心北京100028 西部矿产资源与地质工程教育部重点实验室西安710054

岩石圈有效弹性厚度(T_(e))表征岩石圈综合力学强度,对理解区域深部构造孕震环境具有重要意义.青藏高原东北缘地质构造复杂,强烈地震活动频发.为进一步了解该区域深部岩石圈力学性质特征及其与地震活动的关系,本文利用基于Fan小波的谱方... 详细信息

岩石圈有效弹性厚度(T_(e))表征岩石圈综合力学强度,对理解区域深部构造孕震环境具有重要意义.青藏高原东北缘地质构造复杂,强烈地震活动频发.为进一步了解该区域深部岩石圈力学性质特征及其与地震活动的关系,本文利用基于Fan小波的谱方法,使用WGM2012重力异常数据、ETOPO1地形数据和CRUST1.0模型,通过导纳和相关联合反演计算了青藏高原东北缘的岩石圈有效弹性厚度(T_(e))与荷载比(F).结果显示研究区T_(e)整体呈明显的东高西低分布,青藏块体T_(e)变化剧烈,西部高值(>40 km)和东部低值(30 km),变化相对平缓;荷载比F存在局部西南高,巴颜喀拉和羌塘地块荷载比F较高(>0.5),说明以地下荷载为主,其他地块荷载比F较低(<0.2),以地表荷载为主.鄂尔多斯地块结构稳定,岩石圈强度较大,T_(e)值较高;内部构造活动性微弱,深部物质密度横向变化较小,岩石圈所受荷载以地表为主,荷载比F较低.柴达木地块东部与巴颜喀拉地块东部可能发生有下地壳流,岩石圈较为软弱,T_(e)值较低;巴颜喀拉地块内部与鲜水河断裂的荷载比F较高,岩石圈所受荷载以地下为主,可能是地壳物质向东流动导致岩石圈深部物质密度横向变化较大引起的.通过对比分析研究区T_(e)和T_(e)梯度、F和F梯度与地震之间的对应关系,发现地震一般发生在区域相对低T_(e)值、T_(e)梯度值和荷载比F梯度值较大的区域,震级较小的地震多发生在荷载比F较小的地区,6级以上强震则较多发生在荷载比F约为0.1和0.8的区域.因此,岩石圈有效弹性厚度T_(e)值较低、T_(e)梯度和荷载比F梯度较大的地区,更易出现地震.

关键词：有效弹性厚度荷载比重力异常地震分布

起伏地形下基于非结构网格模型降维的重力三维密度反演

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地球物理学报 2024年第1期67卷 379-393页

作者：高新宇鲁宝亮安国强巨鹏长安大学地质工程与测绘学院西安710054 海洋油气勘探国家工程研究中心北京100028 长安大学西部矿产资源与地质工程教育部重点实验室西安710054

复杂起伏地形以及剖分方式对重力反演解释具有重要影响.目前重力密度反演研究主要基于直立长方体模型,这显著降低了对起伏地形和复杂地质体的拟合程度,对重力反演解释易产生较大影响.四面体非结构网格能够更加精细地模拟起伏地形及复杂... 详细信息

复杂起伏地形以及剖分方式对重力反演解释具有重要影响.目前重力密度反演研究主要基于直立长方体模型,这显著降低了对起伏地形和复杂地质体的拟合程度,对重力反演解释易产生较大影响.四面体非结构网格能够更加精细地模拟起伏地形及复杂地质体,为此本文研究了起伏地形条件下基于四面体非结构网格剖分的重力三维密度反演.首先基于Delaunay方法将地下区域剖分为四面体非结构网格,引入垂向导数和相关系数两种方法进行模型降维技术从而减小解的空间,通过添加最小长度约束,深度加权约束,物性范围约束构建目标函数,并采用预条件共轭梯度法求解.为了提高反演效率在计算过程引入OpenMP并行算法.并研究了各项约束以及两种模型降维方法在四面体非结构网格正则化反演中的效果.通过不同深度直立长方体模型以及起伏地形下组合模型试验,基于四面体非结构网格的重力密度反演可以清晰地反映异常体位置.将本文提出的方法应用于美国密苏里州东南部的氧化铁矿床,反演结果与已知岩体具有较好的一致性,进一步证明该方法的正确性和有效性.

关键词：非结构网格起伏地形密度反演模型降维正则化

基于重磁异常相关分析的场源位置及属性识别方法

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地球物理学报 2020年第4期63卷 1663-1674页

作者：鲁宝亮马涛熊盛青王万银长安大学重磁方法技术研究所长安大学地质工程与测绘学院西部矿产资源与地质工程教育部重点实验室西安710054 中国自然资源航空物探遥感中心北京100083

针对传统的重磁对应分析在场源区域外趋于高相关度的缺点,本文提出了一种基于相关系数和垂向导数的重磁场源位置及属性识别方法,给出了一个新的重磁场源平面位置及属性判别参数(GMCP),该参数能够有效地缩小重磁场源的识别范围.判别参数G... 详细信息

针对传统的重磁对应分析在场源区域外趋于高相关度的缺点,本文提出了一种基于相关系数和垂向导数的重磁场源位置及属性识别方法,给出了一个新的重磁场源平面位置及属性判别参数(GMCP),该参数能够有效地缩小重磁场源的识别范围.判别参数GMCP值非零分布范围反映了场源的规模.GMCP值的正负反映了场源属性,当GMCP大于零时为正相关,代表了该区域存在高磁高密度或低磁低密度的重磁同源地质体;当GMCP小于零时为负相关,代表了该区域存在高磁低密度或低磁高密度的重磁同源地质体;GMCP趋于零,则表示无重磁同源地质体.两组不同干扰水平的同源复杂组合模型实验、两组不同源组合模型试验以及南海中央海盆实际重磁数据处理结果均验证了该重磁场源位置及属性识别方法的正确性和有效性.

关键词：重磁异常场源识别属性判别参数南海海盆

基于UNet++卷积神经网络的重力异常三维密度反演

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地球物理学报 2024年第2期67卷 752-767页

作者：李柏森鲁宝亮安国强巨鹏朱武苏子旺长安大学地质工程与测绘学院西安710054 海洋油气勘探国家工程研究中心北京100028 长安大学西部矿产资源与地质工程教育部重点实验室西安710054 自然资源部生态地质与灾害防控重点实验室西安710054

三维密度反演是地球物理领域的研究热点,而在大数据及人工智能发展的时代背景下如何快速高效地实现重力数据反演显得更为重要.传统反演方法通常需要存储大型系数矩阵,内存占用大,耗费时间长,同时为约束反演结果而加入的正则化约束项参... 详细信息

三维密度反演是地球物理领域的研究热点,而在大数据及人工智能发展的时代背景下如何快速高效地实现重力数据反演显得更为重要.传统反演方法通常需要存储大型系数矩阵,内存占用大,耗费时间长,同时为约束反演结果而加入的正则化约束项参数难以确定;深度学习可以不依赖先验信息,也不需要计算及存储系数矩阵,使得计算效率大大提高.基于此,本文提出了一种基于UNet++网络的重力异常反演方法.首先将UNet++网络中部分参数进行更改:选择在输入数据绝对值较大时梯度更稳定的LeakyRelu作为激活函数;加入了Batch Normalization层,增强了网络的收敛速度及稳定性.然后为了提高网络的全局最优化能力,引入了基于余弦退火的学习率更新策略,使用梯度的一阶以及二阶矩估计的Adam最优化算法,利用数据集与标签集进行网络训练,实现了重力异常的三维密度反演.通过实验验证了UNet++、LeakyRelu更快速稳定的收敛能力,而余弦退火学习率更新策略具有更强的全局寻优能力.含噪模型实验及实际数据反演结果进一步证明该方法的正确性和有效性,及其良好的泛化能力与抗噪能力.

关键词：密度反演重力异常 UNet++ 余弦退火深度学习