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1.
涉县断裂为太行山隆起区内涉县盆地的控盆构造,走向由NE转为近EW向,倾向NW/N,中部在井店东被EW向断裂错断,是控制涉县盆地的一组断裂。本文采用地质地貌调查、河流阶地分析和地质测年等方法,研究了涉县断裂晚第四纪活动特征。研究发现,涉县断裂带由多组断裂构成,带宽约200m,在清漳河两侧表现为山前的陡崖地貌、基岩破碎变形带,具有正断兼走滑特征,在基岩变形带上部发育走向NNE向和NWW向次级滑动面,次级滑动面错断第四系黄土,最新活动到晚更新世;断裂在盆地区通过,地表形成低缓陡坎,断裂错断Q2-3地层,表现为上陡下缓的正断层。通过对涉县断裂两侧清漳河河流阶地、夷平面和地层年龄综合分析,估算涉县断裂晚更新世以来平均垂直滑动速率为0.06~0.08mm/a,中更新世以来平均垂直滑动速率为0.22~0.34mm/a,垂直差异活动主要发生于中更新世期间。 相似文献
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ABSTRACT The Ganjiang River is the largest tributary of Poyang Lake in China, and its hydrological regime variation greatly affects the utilization of regional water resources and the ecological environment of the lake. In this study, a novel trend analysis method, the Moving Average over Shifting Horizon (MASH), was applied to investigate the inter- and intra-annual trends of flow and water level from 1976 to 2016 at the Xiajiang and the Waizhou hydrological stations in the Ganjiang River. The Significant Change Rate Method (SCRM) was proposed to determine the MASH averaging parameters. The trend analysis results show a statistically significant decrease in water level series throughout the year and the relationship of flow and water level have changed greatly at the Waizhou station. The sediment load reduction, large-scale sand mining and water level decrease of Poyang Lake are identified as the main causes for the water level decrease. 相似文献
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文章研究了臭氧及臭氧类高级氧化技术(AOPs-O3)在不同pH条件下降解甲基对硫磷(MP)的效能。结果表明,在pH 3~10的条件下(反应过程控制pH),单独臭氧化5min即可完全降解MP,但不同pH下化学耗氧量(COD)和有机磷的释放率差异明显。在pH为3.3,7.5和9.4的条件下单独臭氧30min后COD的去除率分别为55.17%,89.64%和93.10%,有机磷的释放率分别为16.33%,95.00%和99.99%。考虑酸性条件下可以规避碳酸盐的负面影响(特别是高浓度废水),利用O3/H2O2/Ti(IV)在pH 3.3条件下处理MP溶液,COD去除率和有机磷释放率分别达到89.64%和81.57%。相对法计算求得MP与O3和羟基自由基(·OH)的速率常数分别为31.98L·(mol·s)-1和7.488×109 L·(mol·s)-1。活性污泥法的测试结果表明,MP经O3/Ti(IV)/H2O2(pH=3.3)和O3(pH=9.4)可提升含MP废水的可生化性,但与培养液体系相比仍具有一定的毒性。 相似文献
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Slopes consisting of saturated sand have recently moved down-slope tens or hundreds of meters under the action of earthquakes. This paper presents a simplified but accurate method predicting the triggering and displacement of such landslides. For this purpose, a simplified constitutive model simulating soil response of saturated sands along slip surfaces is proposed and validated. Then, this constitutive model is coupled with the multi-block sliding system model to predict the triggering and displacement of such slides. The multi-block model considers a general mass sliding on a trajectory which consists of n linear segments. The steps needed to apply this method are described in detail. The method was applied successfully to predict the triggering, the motion and the final configuration of the well-documented (a) Higashi Takezawa, (b) Donghekou and (c) Nikawa earthquake-induced slides. 相似文献
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The Eastern Kunlun fault zone (EKLF) is a large left-lateral strike-slip fault, whose slip rate is meaningful to seismic hazard assessment and geodynamics of the Tibetan Plateau. Previous studies suggested that the late Quaternary average slip rate was stable and uniform (10~13 mm/a) in the central and western segment of the EKLF. But there were a few researches of accurate slip rate in the central segment on the EKLF. Therefore, we focused on an offset and well preserved alluvial fan from Xiugou basin, located in the east of Xidatan-Dongdatan, to make it clear. Moreover, we used high-resolution satellite images and digital elevation model extracted from SPOT7 stereo image pairs to restore the offset alluvial fan, and combined terrestrial cosmogenic nuclides method, including 13 quartz-rich samples from this fan surface, 1 quartz-rich sample from the main active channel bed and 1 10Be depth profile from this fan edge to eliminate the 10Be concentration of inheritance accurately, with 1 optically stimulated luminescence sample to obtain the reliable age of this alluvial fan together. Referring to field observations, this alluvial fan was offset left-laterally by (1 862±103) m, and its age is (76.55±3.20)~(106.37±3.38) ka which can be determined through the actual geologic setting and improving chi-square test. Thus, we used the Monte Carlo method to obtain a left-lateral slip rate of (20.3+3.5/-2.3) mm/a with 68% confidence envelopes since the late Pleistocene in the Xiugou basin. As a result, combining with the results of previous studies, the left-lateral slip rate indicated that the obviously decreasing activity transferred from late Pleistocene to Holocene on the central segment of the EKLF. 相似文献
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《地学前缘(英文版)》2023,14(4):101559
Transpression occurs in response to oblique convergence across a deformation zone in intraplate regions and plate boundaries. The Korean Peninsula is located at an intraplate region of the eastern Eurasian Plate and has been deformed under the ENE–WSW maximum horizontal compression since the late Pliocene. In this study, we analyzed short-term instrumental seismic (focal mechanism) and long-term paleoseismic (Quaternary fault outcrop) data to decipher the neotectonic crustal deformation pattern in the southeastern Korean Peninsula. Available (paleo-)seismic data acquired from an NNE–SSW trending deformation zone between the Yangsan and Ulleung fault zones indicate spatial partitioning of crustal deformation by NNW–SSE to NNE–SSW striking reverse faults and NNE–SSW striking strike-slip faults, supporting a strike-slip partitioned transpression model. The instantaneous and finite neotectonic strains, estimated from the focal mechanism and Quaternary outcrop data, respectively, show discrepancies in their axes, which can be attributed to the switching between extensional and intermediate axes of finite strain during the accumulation of wrench-dominated transpression. Notably, some major faults, including the Yangsan and Ulsan fault zones, are relatively misoriented to slip under the current stress condition but, paradoxically, have more (paleo-)seismic records indicating their role in accommodating the neotectonic transpressional strain. We propose that fluids, heat flow, and lithospheric structure are potential factors affecting the reactivation of the relatively misoriented major faults. Our findings provide insights into the accommodation pattern of strain associated with the neotectonic crustal extrusion in an intraplate region of the eastern Eurasian Plate in response to the collision of the Indian Plate and the subduction of the Pacific/Philippine Sea Plates. 相似文献
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滑动速率是研究断裂运动学特征、地震活动性和区域应变分配的重要参数和依据。前人关于甘孜-玉树断裂带滑动速率的研究结果存在较大差异,因此,其晚第四纪滑动速率有待进一步调查研究。本文基于卫星影像解译和野外实地考察,对甘孜-玉树断裂带西段(玉树断裂)上典型断错地貌点进行测量分析,得到玉树断裂晚第四纪走滑速率为6.6±0.1-7.4±1.2mm/a。通过与前人对甘孜-玉树断裂带东段(甘孜断裂)滑动速率的研究结果进行对比,发现甘孜-玉树断裂带东、西段滑动速率不一致,其原因是甘孜断裂的左旋滑移在向西传递的过程中,一部分应变被分配到了巴塘盆地南缘断裂上。巴塘盆地南缘断裂的存在很好地解释了玉树断裂的走滑速率比甘孜断裂偏低的原因。但是,从区域变形来看,巴塘盆地南缘断裂分配的滑动速率恰好说明了甘孜-玉树断裂带东、西段及鲜水河断裂带的水平构造变形是协调一致的。 相似文献
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The photocatalytic activity of combustion synthesized nanocrystalline CeAlO3 was determined for the degradation of four anionic and four cationic dyes. The perovskite oxide showed high‐photocatalytic activity and a complete degradation of all the dyes was possible within 2 h. The photocatalytic activity of the compound was comparable with the activity of the commercial Degussa P‐25 TiO2 catalyst. The degradation of dyes was found to follow first order kinetics and the first order degradation rate constants were determined. 相似文献