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231.
礼县 -罗家堡断裂带晚更新世以来有过明显活动。在礼县—罗家堡段和天水镇—街子口段直接错断全新世地层。断裂沿线地表陡坎发育 ,水系被左旋位错。结合沿该断裂带广泛分布的地震滑坡、砂土液化等 ,认为礼县 -罗家堡断裂带是 1654年天水南 8级地震的发震构造。该断裂晚更新世以来的平均水平位错速率为 0 95mm/a ,平均垂直位移速率为 0 35mm/a ,垂直位移速率约为水平位移速率的 1/ 3。这个比值与一次断裂突发性垂直位错量 ( 1 9m)与水平位错量 ( 5 2m)的比值基本吻合  相似文献   
232.
吸附法盐湖卤水提锂工艺试验   总被引:11,自引:4,他引:11       下载免费PDF全文
张绍成 《盐湖研究》1997,5(1):59-68
用二氧化锰做吸附剂,进行了吸附法盐湖卤水提锂工艺试验,取得了全流程工艺操作条件和技术数据,可做为更大规模试验设计和操作依据。  相似文献   
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本文简述日本的地质构造、火山、地震活动的轮廓和特点;重点报导作者在日本现场考察活动断层和火山的结果;对日本在地学领域研究的特点、经验及趋向进行了概括相评述。  相似文献   
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This study aims to understand the particle size distribution and depositional styles of glacier-associated deposits in the Moxi basin in southwest China. Based on field surveys, 28 samples from glacier-associated deposits (including glacial till, fluvioglacial, debris flow, river and lake deposits) were collected and tested in the laboratory. The results showed that the glacier-associated deposits can be differentiated based on particle gradation, particle size distribution and accumulated percentages. We evaluated the evolution of a former dammed lake in the Moxi basin based on glacier-associated deposits. The results of this study also indicated that the Moxi Platform was not formed by a single depositional process but is composed of both fluvioglacial and debris flow deposits. This research shows that the depositional style analysis is useful in identifying different glacier-associated deposits in high mountain regions. Moreover, the evaluation of the differences in particle sizes of the glacierassociated deposits is useful in reconstructing geohazard events in periglacial regions, and this information can help in identifying and reducing the potential risks associated with geo-hazards.  相似文献   
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稀土元素是研究沉积岩的形成条件及环境特征的重要指标,本文以桂林寨底地下河系统中岩石样品为研究对象,采用激光剥蚀电感耦合等离子体质谱进行稀土元素测试分析,研究了该地区碳酸盐岩的形成环境。结果表明:碳酸盐岩的稀土总量(∑REEs)偏低,不同地层岩性间的∑REEs具有一定差异性,总体上信都组泥质粉砂岩(D2x)的∑REEs最高,其次为融县组(D3r)厚层灰岩和桂林组灰岩(D3g),东村组厚层灰岩(D3d)和额头村组灰岩及白云质灰岩(D3e)的∑REEs较低。整体上表现为重稀土元素相对于轻稀土元素富集的特征,且Ce具有较明显的负异常,而Eu无异常或异常不明显,不同于碎屑岩的轻稀土相对富集、Eu负异常、Ce无异常或异常不明显的特征。这些特征表明研究区碳酸盐岩的形成环境为氧化-海相碳酸盐岩沉积环境,可为定量化判别岩溶区碳酸盐岩形成环境提供依据。  相似文献   
237.
The Kualiangzi landslide was triggered by heavy rainfalls in the “red beds” area of Sichuan Basin in southwestern China. Differing from other bedrock landslides, the movement of the Kualiangzi landslide was controlled by the subvertical cracks and a subhorizontal bedding plane (dip angle < 10°). The ingress of rainwater in the cracks formed a unique groundwater environment in the slope. Field measurement for rainfall, groundwater movement, and slope displacement has been made for the Kualiangzi landslide since 2013. The field monitoring system consists of two rainfall gauges, seven piezometers, five water-level gauges, and two GPS data loggers. The equipments are embedded near a longitudinal section of the landslide, where severe deformation has been observed in the past 3 years. The groundwater responses to four heavy rainfall events were analyzed between June 16 and July 24 in 2013 coincided with the flood season in Sichuan. Results showed that both of the water level and the pore-water pressure increased after each rainfall event with delay in the response time with respect to the precipitation. The maximum time lag reached 35 h occurred in a heavy rainfall event with cumulative precipitation of 127 mm; such lag effect was significantly weakened in the subsequent heavy rainfall events. In each presented rainfall event, longer infiltration period in the bedrock in the upper slope increased the response time of groundwater, compared to that of in the gravels in the lower slope. A translational landslide conceptual model was built for the Kualiangzi landslide, and the time lag was attributed to the gradual formation of the uplift pressure on the slip surface and the softening of soils at the slip surface. Another important observation is the effect on the slope movement which was caused by the water level (H w) in the transverse tension trough developed at the rear edge of the landslide. Significant negative correlation was found for H w and the slope stability factor (F s), in particular for the last two heavy rainfall events, of which the drastic increase of water level caused significant deterioration in the slope stability. The rapid drop (Δ?=?22.5 kPa) of pore-water pressure in the deep bedrock within 1 h and the large increase (Δ?=?87.3 mm) of surficial displacement were both monitored in the same period. In the end, a four-level early warning system is established through utilizing H w and the displacement rate D r as the warning indicators. When the large deformation occurred in flood season, the habitants at the leading edge of the landslide can be evacuated in time.  相似文献   
238.
基本层序在垂向上的重大转化面即为基本层序界面,由高到低可划分为旋回性基本层序/不显旋回性基本层序间界面(Ⅰ级界面)、旋回性基本层序/韵律性基本层序间界面(Ⅱ级界面)和向上变细粒序/向上变粗粒序间界面(Ⅲ级界面)。这些界面广泛发育于碎屑沉积岩中,因而是细分地质填图单位的重要选择界面。这一方案是对传统沉积序列分层及地质填图单位界面选择的重要补充,对指导中国造山带巨厚碎屑岩建造的地质填图单位划分、沉积相分析和区域地质研究具有重要意义。  相似文献   
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