Potential of quartz OSL dating on moraine deposits from eastern Tibetan Plateau using SAR protocol     

XianJiao Ou  LiuBing Xu  ZhongPing Lai  Hao Long  Zhong He  QiShun Fan  ShangZhe Zhou 《Quaternary Geochronology》2010,5(2-3):257-262

Optically stimulated luminescence (OSL) dating methods have been widely applied in Quaternary glaciology. However, glacigenic deposits are considered in general as problematic for OSL dating, mainly because they are transported shorter distances prior to burial and are usually partially bleached. Thus, most researchers choose glaciofluvial and glaciolacustrine sediments (with relatively longer transportation times) for OSL dating when constraining the age of glaciation. In this study, four samples were collected from a lateral moraine series at Zhuqing Village, northern margin of Queer Shan Mountain, eastern Tibetan Plateau, in order to investigate the applicability of OSL dating for morainic deposits. Quartz grains (38–63 μm) were extracted and measured using single aliquot regenerative-dose (SAR) protocol. Internal checks and dose recovery test show that the SAR protocol is appropriate for equivalent dose (D_e) determination. The effect of thermal transfer is small for all samples and the recycling ratio for each individual sample is close to unity. The symmetry in the D_e distributions indicates that quartz grains were well-bleached prior to burial. OSL ages show good agreement with geomorphological and field investigations, and are also concordant with an independent ESR age. It is concluded that: (a) the morainic deposits in Zhuqing were well-bleached and suitable for OSL dating; (b) SAR protocol can be applied to morainic deposits for samples under study.  相似文献   

陆相特殊沉积的研究方法及气候意义   总被引：1，自引：0，他引：1       下载免费PDF全文

田馨  向芳  罗来  宋见春 《地学前缘》2009,16(5):71-78

陆相沉积形成于地圈与水圈、大气圈和生物圈的交界面上,比海相地层更有效地记录了地球表层环境的信息。通过对沉积岩中沉积物的粘土矿物、气候指数、氧同位素测温等研究,获得关于气候干湿冷暖的信息。基于对这些常用方法的研究,提取出一些陆地上的特殊沉积,如：陆相红层、沙漠沉积体系、蒸发岩、煤及油页岩等所包含的丰富气候信息。沙漠代表干旱炎热气候;陆相红层的出现反映高温氧化环境,其在干旱和潮湿的热带气候下都能形成;芒硝代表干冷的气候环境;石膏则代表干热,水体盐度高,蒸发作用强的气候条件;煤层/油页岩一般形成于温暖潮湿的气候环境。对特殊沉积的研究可以用来重建古气候和恢复大陆古环境。  相似文献   

Fault zone structures of northern and southern portions of the main central fault generated by the 2008 Wenchuan earthquake using fault zone trapped waves   总被引：1，自引：0，他引：1  

Songlin Li  Xiaoling Lai Zhixiang Yao  Qing Yang Geophysical Prospecting Center  China Earthquake Administration  Zhengzhou  China Institute of Geophysics  Beijing  China 《地震学报(英文版)》2009,(4):417-424

The rupture process of the May 12,2008 MS8.0 Wenchuan earthquake was very complex. To study the rupture zones generated by this earthquake,four dense temporary seismic arrays across the two surface breaking traces of the main-shock were deployed in July and recorded a great amount of aftershocks. This paper focuses on the data interpretation of two arrays across the central main fault,the northern array line 1 and southern array line 3. The fault zone trapped waves recorded by the two arrays were used to st...  相似文献   

龙门山断裂带断层围陷波探测     

赖晓玲  李松林 《国际地震动态》2009,(4):86-86

2008年5月12日在四川省汶川地区发生了8级特大地震,断裂长度达300km,地震中最大错位10m以上,造成震区地面建筑大面积倒塌和大量人员伤亡,并诱发了严重的地质灾害,毁坏了公路、桥梁等交通系统和通讯设施。由于地震的发生和破坏程度与地壳内部断裂构造的形态和分布之间有着密切的关系,因此,尽快确定龙门山断裂带目前的状况。探明各分支断层的位置和几何形态,  相似文献   

基于次序权重平均法的购房选择地理空间多准则决策     

胡卓玮  刘晓旭  彭程  魏铼 《地理研究》2013,32(3):476-486

居民的购房选择是对居住区位进行选择的复杂过程,其实质是居住空间的个人行为决策问题。在调研工作基础上,论文分析并构建了居民购房选择决策评价指标体系,以北京市为实验区应用GIS制作居住适宜性基础准则(指标)地图。研究一种可以适应购房者差异化的购房需求与偏好的购房地理空间决策方法,通过层次分析法提取购房个体的偏好信息,确定个人准则权重。采用次序加权平均算法(Ordered Weighted Averaging,OWA)针对个人准则权重计算个人次序权重,结合二者对居住适宜性基础准则地图进行集结,计算多种决策风险下的个人居住适宜性准则地图,对意向住房进行分析评价,动态生成相应决策方案,为购房者提供购房决策支持,减少主观意愿与客观环境带来的决策风险。最后通过一个实验对以上方法进行实现。  相似文献   

川中蓬莱地区须家河组须二段储层成岩相与优质储集层预测     

赖锦  王贵文  陈阳阳  黄龙兴  张莉莉  王迪  孙艳慧  李梅 《吉林大学学报(地球科学版)》2014,44(2):432-445

通过岩心观察并综合利用普通薄片、铸体薄片和扫描电镜分析等资料,对须二段储层岩石学特征、物性及孔隙结构特征、成岩作用、成岩矿物、成岩环境、所处成岩阶段和成岩演化序列等进行了研究。结果表明,须二段储层经历压实压溶、胶结、溶蚀和破裂等成岩作用,现今处于中成岩A 期。根据成岩作用类型和强度、成岩矿物及其对储层物性的影响划分出3种成岩相：强压实自生矿物胶结相、强压实不稳定组分溶蚀相和破碎裂缝相。选取了对成岩相较敏感的声波时差、电阻率、自然伽马、密度和中子5条常规测井曲线和成像测井资料,通过岩心资料刻度测井建立了各成岩相的测井识别标准,将成岩相进行剖面展开和平面成图。再根据有利成岩相的平面展布规律,对蓬莱地区须二段优质储层发育带进行了预测,认为平面上的斜坡中部为主要的优质储集层发育区。  相似文献   

加强地方地震工作的重要性     

王绍然  刘其寿  杨佩琴  李远兴  赖福霖  郑永通 《国际地震动态》2012,(10):33-37

结合龙岩市防震减灾工作的实际,分析地方地震部门所具有的社会职能,并从宏观职能、微观职能、联合职能、管理职能4个方面进行探讨,说明地方地震部门应正确行使职能,提出加强地方地震工作的重要性。  相似文献   

Apparent permeability variation of underground water aquifer induced by an earthquake: A case of the Zhouzhi well and the 2008 Wenchuan earthquake          下载免费PDF全文

Guijuan Lai  Fuqiong Huang  Hongkui Ge 《地震科学（英文版）》2011,24(5):437-445

Taking the M₂ wave as calibration signals, we extract the phase shifts of the water level relative to the Earth tide in the Zhouzhi well by utilizing the cross-correlation function. And we further obtain the apparent permeability variation in the aquifer of the Zhouzhi well in 2008. Comparison with the commonly used tidal analysis software Baytap-G shows that phase shifts obtained by cross-correlation function are more stable. The resulting apparent permeability of the Zhouzhi well aquifer fluctuates with time, indicating it is a dynamically controlled parameter. The 2008 Wenchuan earthquake caused the apparent permeability increasing drastically, which is interpreted as the combination effects of effective stress changes and the barriers removing in the flow channel due to seismic wave pressure pulse. After the Wenchuan earthquake, the effective stress began to recover and the impurities deposited gradually, causing the apparent permeability to decrease a month later and almost recover to the pre-earthquake level in six months.  相似文献   

花岗岩演化与铀钍元素富集的关系:以粤北贵东岩体为例   总被引：3，自引：0，他引：3       下载免费PDF全文

娄峰  李宏卫  陈光明  敖文波  赖中信  卢映新  杨燕娜 《地学前缘》2011,18(1):110-117

对粤北贵东岩体铀钍丰度变化特征的研究表明,原地重熔过程导致铀钍元素向花岗岩体的上方汇聚富集,并造成铀、钍元素在空间上的分离,即在花岗岩体中,铀的丰度带位处钍丰度带之上。陆壳多次原地熔融(重熔)不但导致复式花岗岩体形成,同时造成铀元素在晚期岩体中的富集。贵东岩体内燕山早期岩体铀钍含量的东西差异被认为与卷入熔融的铀源层(寒武-震旦系)的初始埋深有关,而复式岩体铀含量的南北差异,则被解释为与晚期重熔界面倾斜方向所导致的晚期岩体的剥蚀深度有关。高铀含量和高铀钍比值并存往往是晚期岩体埋深较浅的表现,对于深部隐伏矿床的寻找有重要指示作用。  相似文献   

水汞测量过程中干扰因素的探讨   总被引：3，自引：0，他引：3  

陈华静  申春生  来淑琴 《地震》1999,19(3):291-296

汞是地下流体监测预报地震的灵敏组分之一,针对目前汞观测网中出现的突出问题——汞测量方法中的干扰因素进行了剖析,指出蒸馏水、化学试剂、温度和吸附作用是造成观测结果波动大的主要原因,并提出了减少误差、排除干扰和识别异常的方法。  相似文献