期刊文献+
共找到10篇文章
< 1 >
每页显示 20 50 100
中国庐山地区大校场晚第四纪沉积年龄测定及层序地层学 被引量:2
1
作者 胡东生 胡蓉 +5 位作者 李小豫 胡文瑄 王旭龙 田新红 刘卫国 张国伟 《中国工程科学》 北大核心 2012年第11期36-43,48,共9页
通过庐山科学考察(1997—2009)对大校场沟口晚第四纪剖面地层进行精细研究,采用古地磁、电子自旋共振(ESR)、36Cl、释光法等多种仪器测年方法的分析,建立了完整剖面的全时段地层的自400 ka.B.P.以来的系列年龄数据,与之相对应识别出Biwa... 通过庐山科学考察(1997—2009)对大校场沟口晚第四纪剖面地层进行精细研究,采用古地磁、电子自旋共振(ESR)、36Cl、释光法等多种仪器测年方法的分析,建立了完整剖面的全时段地层的自400 ka.B.P.以来的系列年龄数据,与之相对应识别出Biwa-III(320 ka.B.P.)事件、Biwa-II(260 ka.B.P.)事件、Biwa-I(180 ka.B.P.)事件(因铁盘扰动影响缺失)、Blake(100 ka.B.P.)事件、Laschamp(20 ka.B.P.)事件(因表层活动影响未发育)等古地磁极性事件,结合层序地层和层型特征及沉积环境将剖面地层由早至晚划分为4个发展旋回阶段:I阶段为冰期(400~200 ka.B.P.)气候时期,II阶段为间冰期(200~100 ka.B.P.)气候时期,III阶段为冰缘期(100~10 ka.B.P.)气候时期,IV阶段为冰后期(10~0 ka.B.P.)气候时期。 展开更多
关键词 晚第四纪沉积 多种器测定年数据 层型序列及综合年龄 沉积旋回阶段 庐山大校场
下载PDF
前湖湾晚第四纪沉积物粒度及磁化率特征分析
2
作者 刘巍 俞鸣同 +1 位作者 龚正权 陈有喜 《安全与环境学报》 CAS CSCD 北大核心 2009年第2期68-71,共4页
为进一步探索福建闽南沿海晚第四纪环境及气候演变的规律,选取漳浦前湖湾的海岸剖面以及海岸、海滩两个钻孔作为代表剖面,并对剖面(D2)进行间距10 cm刻槽,共采样70个,对钻孔岩芯进行10 cm的等间距采样,其中剖面延续性钻孔CHHA采样72个,... 为进一步探索福建闽南沿海晚第四纪环境及气候演变的规律,选取漳浦前湖湾的海岸剖面以及海岸、海滩两个钻孔作为代表剖面,并对剖面(D2)进行间距10 cm刻槽,共采样70个,对钻孔岩芯进行10 cm的等间距采样,其中剖面延续性钻孔CHHA采样72个,海滩对比钻孔CHHT采样38个。另外选取当地海岸的风砂堆积物、海滩沉积物、河流沉积物作为典型沉积环境判别的参考。进行两项实验:1)对所有样本进行粒度测试;2)对所有样本进行高低频磁化率的测试。通过实验获得了距今4万年以来的沉积物粒度数据和相应时期的磁化率数据。研究表明:1)当地气候形成经历了湿热、干冷、更干冷、湿热4个大的冷暖交替时期;2)前湖湾的环境经历了由河流沉积环境转为海滩沉积环境,再转为风砂堆积环境的变迁;3)古树林很可能原生于此,后因海面上涨而被现代海滩沉积覆盖。 展开更多
关键词 自然地理学 晚第四纪沉积 漳浦 磁化率 粒度
下载PDF
渤海湾北岸晚第四纪沉积物物理力学性质及其对地面沉降的影响 被引量:4
3
作者 秦雅飞 胥勤勉 +3 位作者 姜洪涛 方成 袁桂邦 杨吉龙 《地质调查与研究》 2014年第2期123-130,共8页
对渤海湾北岸晚第四纪沉积物进行详细的沉积学、年代学和物理力学性质分析研究发现,渤海湾北岸50 m以浅自上而下分为九个单元,依次为第一海相层、滨海湖、末次冰消期湖沼、末次冰消期初期沼泽、盛冰期硬粘土、河床、第二海相层、末次冰... 对渤海湾北岸晚第四纪沉积物进行详细的沉积学、年代学和物理力学性质分析研究发现,渤海湾北岸50 m以浅自上而下分为九个单元,依次为第一海相层、滨海湖、末次冰消期湖沼、末次冰消期初期沼泽、盛冰期硬粘土、河床、第二海相层、末次冰期间冰阶湖沼和末次冰期泛滥堆积。自然压缩固结引发的地面沉降与沉积物的含水率、孔隙比、黏聚力和压缩系数等物理力学性质关系密切。第一海相层的各项指数均较高,其次为第二海相层和末次冰消期的泛滥沉积,最小为盛冰期的硬粘土和末次冰期泛滥沉积。以孔隙比和压缩系数为指标,假设第一海相层压缩固结到沉积环境相似的第二海相层,需要压缩固结196.2 cm;末次冰消期泛滥沉积压缩固结到沉积环境相似的末次冰期泛滥沉积,需要压缩固结114 cm。30 m以浅地层的自然固结压缩速率最大为0.04 mm/a,远远小于目前的地面沉降速率。 展开更多
关键词 渤海湾北岸 晚第四纪沉积 物理力学性质 地面沉降
下载PDF
龙泉山西麓晚第四纪以来的沉积及构造意义 被引量:2
4
作者 张威 马超 《四川地震》 2019年第4期7-10,共4页
龙泉山西麓山前晚第四纪沉积发现两套不同类型的粘土沉积,这为研究沉积和构造的关系提供了载体。通过详细的野外地质调查、粒度和钻孔分析,结果表明:成都粘土在龙泉山西麓主要分布在洛带以北的地区,形成于晚更新世晚期,属于近源的风成... 龙泉山西麓山前晚第四纪沉积发现两套不同类型的粘土沉积,这为研究沉积和构造的关系提供了载体。通过详细的野外地质调查、粒度和钻孔分析,结果表明:成都粘土在龙泉山西麓主要分布在洛带以北的地区,形成于晚更新世晚期,属于近源的风成沉积。柏合粘土在龙泉山西麓主要分布在洛带和太平镇之间,物源来自于龙泉山,属于静水环境条件下的沉积。龙泉山西麓第四纪沉积物形成时代及厚度的变化反映了来自于龙门山的挤压力是持续的和非均匀性的,其潜在的地震风险性应引起足够的重视。 展开更多
关键词 青藏高原 龙泉山西麓 晚第四纪沉积 构造意义
下载PDF
鄱阳湖地区晚第四纪风沙沉积的研究现状和展望 被引量:3
5
作者 王志刚 李志文 黎武标 《内蒙古师范大学学报(自然科学汉文版)》 CAS 北大核心 2017年第6期845-852,共8页
以定性与定量为基础,查阅半个世纪以来鄱阳湖地区风沙沉积与气候变化的相关研究报道,通过资料收集与整理、综合分析与总结,深入分析了风沙沉积的空间分布、沉积特征、地质时代、古地理环境等特征.研究结果表明,该地区广泛分布的风沙沉... 以定性与定量为基础,查阅半个世纪以来鄱阳湖地区风沙沉积与气候变化的相关研究报道,通过资料收集与整理、综合分析与总结,深入分析了风沙沉积的空间分布、沉积特征、地质时代、古地理环境等特征.研究结果表明,该地区广泛分布的风沙沉积是末期冰期气候环境变化的产物. 展开更多
关键词 鄱阳湖地区 晚第风沙沉积 研究现状 展望
下载PDF
闽南沿海晚第四纪环境演变探讨
6
作者 刘巍 俞鸣同 +1 位作者 龚正权 陈有喜 《宁德师专学报(自然科学版)》 2009年第4期363-367,共5页
选取前湖湾的海岸剖面以及海岸、海滩两个钻孔作为代表剖面,探索闽南沿海晚第四纪环境演变的规律,对剖面、钻孔岩芯进行10cm的等间距采样.选取当地海岸的风砂、海滩、河流沉积物作为环境判别的参考,使用激光粒度仪进行粒度测试.研究表明... 选取前湖湾的海岸剖面以及海岸、海滩两个钻孔作为代表剖面,探索闽南沿海晚第四纪环境演变的规律,对剖面、钻孔岩芯进行10cm的等间距采样.选取当地海岸的风砂、海滩、河流沉积物作为环境判别的参考,使用激光粒度仪进行粒度测试.研究表明:(1)42kaB.P.以来前湖湾经历了海滩、河口河流、湖沼、海滩环境,再转为沙丘砂堆积环境的变迁;(2)古树林因42kaB.P.海面上涨被海滩沉积物所覆盖. 展开更多
关键词 漳浦 晚第四纪沉积 粒度 环境演变
下载PDF
Carbon and oxygen isotope characteristics of foraminiferan from northern South China Sea sediments and their significance to late Quaternary hydrate decomposition 被引量:5
7
作者 雷怀彦 曹超 +2 位作者 欧文佳 龚楚君 史春潇 《Journal of Central South University》 SCIE EI CAS 2012年第6期1728-1740,共13页
Carbon and oxygen isotope and dating analyses of foraminiferan in sediment cores collected from three different areas of the northern slope of the South China Sea were conducted, in order to examine the records of the... Carbon and oxygen isotope and dating analyses of foraminiferan in sediment cores collected from three different areas of the northern slope of the South China Sea were conducted, in order to examine the records of the gas hydrate decomposition events since the late Quaternary under the conditions of methane seepage. The results show that: 1) the δ13C values of the benthic foraminiferan Uvigerina spp. (size range of 0.25-0.35 ram) are from -0.212% to -0.021% and the δ180 values of the planktonic foraminiferan Globigerinoides ruber (size range of 0.25-0.35 ram) are from -0.311% to -0.060%; 2) three cores (ZD2, ZD3 and ZS5) from the bottom of a hole are aged for 11 814, 26 616 and 64 090 a corresponding to the early oxygen isotope stage (MIS) Ⅰ, Ⅲ and Ⅳ final period, respectively; 3) a negative-skewed layer of carbon isotope corresponds to that of MIS II (cold period), whose degree of negative bias is -0.2%0; and 4) the δ13C compositions of foraminiferans are similar to those of the Blake Ridge and the Gulf of Mexico sediments of the late Quaternary. According to the analysis, the reasons for these results are that the studied area is a typical area of methane seep environment in the area during MIS II due to the global sea-level fall and sea pressure decrease. Gas hydrate is decomposed and released, and a large number of light carbon isotopes of methane are released into the ocean, dissolved to inorganic carbon (DIC) pool and recorded in the foraminiferan shells. A pyrite layer developed in the negative bias layers of the foraminiferans confirms that the δ13C of foraminiferans is more affected by methane and less by the reduction of marine productivity and early diagenesis. The use of foraminiferan δ13C could accurately determine late Quaternary hydrate release events and provide evidence for both reconstructing the geological history of methane release events and exploring natural gas hydrate. 展开更多
关键词 northern South China Sea foraminiferan carbon and oxygen isotopes natural gas hydrate
下载PDF
Study of the Late Quaternary Slip Rate Along the Northern Segment on the South Branch of the Longling-Ruili Fault
8
作者 Huang Xuemeng Du Yi Shu Saibin Xie Furen 《Earthquake Research in China》 2010年第4期456-466,共11页
The Longling-Ruili fault is an important active fault in Southwestern China, striking generally northeast. The fault controls the development of the sedimentary series and magmatic action on its two sides, as well as ... The Longling-Ruili fault is an important active fault in Southwestern China, striking generally northeast. The fault controls the development of the sedimentary series and magmatic action on its two sides, as well as the development of the Longling basin, Mangshi basin and the Zhefang basin along it. Due to limited Quaternary sediments and harsh natural conditions, the study of late Quaternary fault activity on the northern segment of the Longling-Ruili fault is lacking and the time of the newest faulting and the Quaternary slip rate are not clear at present. Based on the interpretation of remote images, quantitative geomorphologic deformation measurements and dating of young terrace deposits and alluvial fans, this paper obtains some new results as follows. The northern segment of the Longling-Ruili fault is a Holocene dextral strike-slip fault with some component of a normal slip. The terrace T1 composing mainly of alluvial deposits formed during 4ka B. P. was offset by the northern segment of the Longling-Ruili fault and its left-lateral and its vertical displacements are 8m - 12m and 2m, respectively. The late Pleistocene alluvial fan was displaced with a left-lateral and vertical displacement of 70m and lgm, respectively. The strike-slip rate of the Longling-Ruili fault is 2.2mm/a 2.5mm/a and the vertical slip rate is 0.6mm/a since the late Pleistocene epoch. The strike-slip rate of the Longling-Ruili fault is 1.8mm/a - 3.0mm/a and vertical slip rate is 0.5mm/a during the Holocene epoch. The proportion of horizontal to vertical displacement is about 4: 1, which means that the vertical slip rate on the northern segment of the Longling-Ruili fault is about 25 % of the horizontal slip rate. The left-lateral slip rate in the late Holocene is consistent with the GPS measurement. The strike slip rate is of great consistency in different time scales since the late Pleistocene epoch, indicating that the activity of the Longling-Ruili fault is of great stability. 展开更多
关键词 The Longling-Ruili fault Late Quaternary Faulted landform Slip rate
下载PDF
Geometric Structure and Tectonic Activities of Wanquan Fault,Hebei Province
9
作者 Zhou Jianglin You Huichuan +4 位作者 Zhou Yueling Shao Cuiru Yang Qiyan Li Jinjin Zhang Zhengyu 《Earthquake Research in China》 2013年第2期223-232,共10页
Based on detailed investigations and prospecting,this paper describes the geometrical characteristics and tectonic activities of Wanquan fault in northwest of Beijing. This fault strikes mainly northeast or northeast ... Based on detailed investigations and prospecting,this paper describes the geometrical characteristics and tectonic activities of Wanquan fault in northwest of Beijing. This fault strikes mainly northeast or northeast to north,dipping southeast,and extends over a length of 15km. It is a major geological and geomorphological margin,controlling the neotectonic movement in this region. On the southeast side of Wanquan fault are the Late Quaternary unconsolidated deposits,forming a basin or deposition; but on the other side is Mesozoic volcano debris,forming lower-mountains and hills. Wanquan fault is a mid- to-high-angle normal fault dipping southeast. This fault was more active in the Quaternary. Since the middle-late part of the alate Pleistocene,the average rate with vertical slip of a single fault is over 0. 03 ~ 0. 3mm /a,but the fault has multiple slipping surfaces,and a total rate with vertical slip will be estimated. 展开更多
关键词 Wanquan fault Geometric structure Tectonic activities
下载PDF
陆地地貌
10
《中国地理科学文摘》 1997年第1期16-19,共4页
关键词 陆地 珠江三角洲 晚第四纪沉积 沉积旋回 全新世 沉积特征 更新世 充填层序 海陆过渡相 SEDIMENT
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部