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近年来,在青岛地区对第四纪断裂的空间展布、结构面和地貌特征及其与第四纪地层的关系等进行了较为详细的研究,并采用热释光(TL)及电子自旋共振(ESR)法对断层物质及断裂带上覆的第四纪堆积物的年龄进行了测定。文中对上述研究成果进行了初步总结,认为青岛及邻区内的NE向断裂在空间展布、地貌特征及最新活动时代等方面具有相似性,它们的最新活动时代为中更新世中晚期,晚更新世以来不活动。除此以外未见其它方向的晚更新世以来活动的断裂,结合历史地震及现代小震活动特点分析,认为该区域内无≥6级地震的发生条件,但有发生5级左右地震的可能性。 相似文献
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深井盆地南缘断裂特征与活动性研究 总被引:1,自引:0,他引:1
深井盆地是山西断陷盆地带北段内部一个规模很小的次级盆地,为中更新世以来发育的三角型山间小型盆地。盆地附近断裂发育,构造复杂,深井盆地南缘断裂为主控边界断裂,控制着盆地的发展演化。本文通过对地形地貌、断裂剖面、地层测年及地震活动等方面的分析和研究,获得了断裂活动时代和活动速率等参数,综合阐述了断裂的空间展布及活动特征。研究表明:深井盆地南缘断裂晚第四纪期间仍在活动,最新活动时代为晚更新世晚期;断裂具有分段性,西段长约6km,多处可见断裂错断晚更新世地层剖面,属正断倾滑性质;东段表现为盆地与黄土斜坡直接接触,由西向东断裂地貌表现逐渐减弱,未见明显的断裂剖面,止于NW向构造,附近发生的4次4 3/4级地震与该段断裂关系密切。 相似文献
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柯坪推覆构造的根部断裂记录到的地震活动相对较弱,以至于多数学者认为该断裂晚第四纪以来活动性不强。笔者根据遥感影像解译和野外调查得到迈丹断裂的几何展布,确认F3阿合奇段为最新地表破裂带,并通过一系列河流阶地的左旋位移测量确定其晚更新世以来有过走滑活动。结合地貌测量和探槽开挖得到断层垂直错距,探槽揭示的古地震事件发生在距今(1.76±0.22)ka之后,根据现场考察获得的活动构造定量数据,依据不同震级与地表破裂关系式推算出该次古地震震级为7.5级。研究成果可能对区域活动断裂的研究以及区域活动构造图像的完整性提供基础资料,同时最新地表破裂证据的发现可能有助于更新认识该断裂的危险性。 相似文献
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通过对汗母坝-澜沧断裂晚第四纪地质、地貌实地调查与测量,并结合前人研究成果,讨论了该断裂晚第四纪最新构造活动特征。综合分析认为,汗母坝-澜沧断裂为一条以右旋走滑为主的全新世活动断裂,长约120 km,整体走向NNW。该断裂活动习性具有明显的分段特征,北段称为汗母坝断裂,是1988年耿马7.2级地震的发震断裂;南段称为澜沧断裂,是1988年澜沧7.6级地震的发震断裂之一。晚第四纪以来其新活动形成了丰富的断错地貌现象,如冲沟和山脊右旋位错、断层沟槽、断层垭口、断层陡坎、断陷凹坑等。根据断裂断错地貌特征的相应资料估计,该断裂晚第四纪右旋走滑速率约为(4.7±0.5) mm/a。 相似文献
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利用地质地貌调查、 探槽、 工程探测以及年代测试等方法, 对双山—李家庄断裂的地表破裂形态、 最新活动性以及古地震事件展开研究。 结果表明: ① 双山—李家庄断裂的最新活动时代为晚更新世, 在 (17.0±0.85) ka~(21.4±1.7) ka B.P.之间, 总体以左旋走滑正断为主, 局部逆断。 依据第四纪活动特征和破裂形式, 从南往北可分为两段, 即南段(双山—大马山)和北段(大马山—五里)。 其中南段又可分为3个小段: 双山—丹河水库小段表现为左阶斜列状展布的两条断层, 以左行走滑兼正断活动为主; 丹河水库—营子小段表现为两条相交的断裂, 东支在剖面上则表现为正断活动, 第四纪以来不活动; 西支在剖面上以逆冲破裂为主, 最新活动时代为晚更新世; 营子—大马山小段隐伏于第四系之下, 具有正断走滑破裂特征。 北段总体表现为多条近平行的断裂构造系, 破裂形式以逆断为主。 ② 双山—李家庄断裂晚第四纪以来可能发生过两次古地震事件, 分别发生在(17.0±0.85) ka~(21.4±1.7) ka B.P.和(77.0±3.8) ka~(84.0±4.2) ka B.P.。 ③ 1829年青州、 临朐61/4级地震的发生与上五井断裂和双山—李家庄断裂构成的“X”型共轭构造密切相关, 双山—李家庄断裂很可能就是这次地震的发震构造。 鲁西断块内发育的多条与双山—李家庄断裂相似的NW向晚更新世活动断裂, 均具有发生6级左右地震的构造条件, 因此, 今后应加强这些断裂的活动断层探测和地震监测研究, 为地震防御工作提供可靠依据。 相似文献
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本文根据攀西地区活断层长期滑动速率及历史上最大地震震级上限,把攀西地区的活断层划分为A、B、C三级,并对区内几条主要活断层的近代活动特征进行了较全面的研究。指出第四纪断裂活动沿断裂带在空间上和时间上是有明显的分段性和不均匀性,断裂上的位移是以一种地震构造上的脉冲形式出现的,地震与晚更新世、全新世和现代断裂活动在空间上和成因上有密切的联系。 相似文献
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Tang Rongchang Huang Zuzhi Qian Hong Gong Yu Wen Dehua Ma Senghao and Zhou RongjunSeismological Bureau of Sichuan Province Chengdu China 《中国地震研究》1997,(1)
Chengdu fault depression is an important Quaternary basin in the piedmont of Longmenshan mountain.Formation and evolution of the fault depression are entirely controlled by the Longmenshan piedmont fault and the Longquanshan fault.Since the late Quaternary,Chengdu fault depression has been subjected to an NW-SE oriented compression.Many NE or NNE trending faults inside the depression or near its margins show thrust slip,resulting in moderate and strong earthquakes along the piedmont Longmenshan fault,the western slop Longquanshan fault,and Pujiang-Xinjin-Chengdu-Deyang fault.It is indicated that three faults as mentioned above have the potential capability for the occurrence of moderate earthquakes. 相似文献
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Huang Qingtuan 《中国地震研究》2005,19(2):214-223
INTRODUCTION TheLonghai ZhangpucoastalareaofFujianProvinceliesonthesouthernsideoftheoutletofthe JiulongjiangRiver.Tectonically,itislocatedonthesouthernsegmentoftheChangle Zhao’anfault zone.Previously,alotofseismogeologicresearchworkhasbeencarriedoutinthi… 相似文献
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长江三峡狮子口地区断层最新活动年龄及工程评价 总被引:6,自引:0,他引:6
经野外调查和验证,长江三峡狮子口地区的NNW向遥感线性形迹是地形、岩性和小型断层的反映。对区内断层带样品进行的同位素年龄测定,判定出青林口断层在距今49×r04a曾有轻微活动,其余的四条断层第四纪(240×104a)以来无活动。地貌、地质和微震(M<3)分布表明,这些断层现代是不活动的,非控震构造,对三峡水库、大坝工程稳定性无影响 相似文献
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《中国地震研究》2017,(3)
In this paper,according to the results of the satellite imagery interpretation and field investigation,we study the active features and the latest active times of the ChuxiongNanhua fault,the Quaternary basins formation mechanism,and the relationship between the fault and the 1680 Chuxiong M_S6 3/4earthquake. Several Quaternary profiles at Lvhe,Nanhua reveal that the fault has offset the late Pleistocene deposits of the T2 and T3 terraces of Longchuan river, indicating that the fault was obviously active in late Quaternary. The Chuxiong-Nanhua fault has been dominated by dextral strike slip motion in the late Quaternary,with an average rate of 1. 6-2. 0 mm/a. Several pull apart Quaternary basins of Chuxiong,Nanhua,and Ziwu etc. have developed along the fault.The 1680 Chuxiong M_S6 3/4earthquake and several moderate earthquakes have occurred near the fault. The Chuxiong-Nanhua fault are the seismogenic structure of those earthquakes,the latest fault movement was in the late-Pleistocene,and even the Holocene.In large area,the Chuxiong-Nanhua fault and the eastern Qujiang fault and the Shiping fault composed a set of NW-trending oblique orientation active faults,and the motion characteristics are all mainly dextral strike slip. The motion characteristics,like the red river fault of the Sichuan-Yunnan Rhombic Block southwestern boundary,are concerned with the escaping movement of the Sichuan-Yunnan Rhombic Block. 相似文献
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Huang Qingtuan 《中国地震研究》2007,21(2):210-224
On the southeast coast of Fujian and its adjacent area, the NE-trending Changle-Zhao′an fault zone and several NW-trending faults that are genetically related to the former are well developed. With micro-relief analysis, the paper deals with the Quaternary activity of the faults and the tectonic stress field since the late Pleistocene in this region. The results indicate that the micro-relief of the NE-trending Changle-Zhao′an fault zone and the genetically related NW-trending faults is characterized by vertical and horizontal movements since the Quaternary; the faults in the region have undergone two active stages since the Quaternary, i.e. early Quaternary and late Pleistocene; since the late Pleistocene, the movement of the NE-trending faults showed a right-lateral strike-slip, while that of NW-trending faults a left-lateral strike-slip, indicating a NWW-SEE oriented horizontal principal stress of the regional tectonic stress field 相似文献
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西藏尼木南北向活动构造带的初步研究 总被引:2,自引:0,他引:2
西藏尼木南北向活动构造带是西藏高原上著名的当雄—羊八井—多庆错活动构造带的组成部份,具有强烈的第四纪活动性。它由活动断裂和裂陷型断陷盆地两大部份构成。盆地内的地貌特征显示它在第四纪持续沉降的特点。该带中的活动断裂主要有两组,即南北向和北北东向。第四记的强烈活动在带内留下了众多的断错地貌现象,南北向活动断裂的主要活动时期较早,在更新世。北北东向活动断裂的主要活动时期较晚,在全新世。 相似文献
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In this paper, according to the results of the satellite imagery interpretation and field investigation, we study the active features and the latest active times of the Chuxiong-Nanhua fault, the Quaternary basins formation mechanism, and the relationship between the fault and the 1680 Chuxiong MS6 ¾ earthquake. Several Quaternary profiles at Lvhe, Nanhua reveal that the fault has offset the late Pleistocene deposits of the T2 and T3 terraces of Longchuan river, indicating that the fault was obviously active in late Quaternary. The Chuxiong-Nanhua fault has been dominated by dextral strike slip motion in the late Quaternary, with an average rate of 1.6-2.0mm/a. Several pull apart Quaternary basins of Chuxiong, Nanhua, and Ziwu etc. have developed along the fault. The 1680 Chuxiong MS6 ¾ earthquake and several moderate earthquakes have occurred near the fault. The Chuxiong-Nanhua fault are the seismogenic structure of those earthquakes, the latest fault movement was in the late-Pleistocene, and even the Holocene. In large area, the Chuxiong-Nanhua fault and the eastern Qujiang fault and the Shiping fault composed a set of NW-trending oblique orientation active faults, and the motion characteristics are all mainly dextral strike slip. The motion characteristics, like the red river fault of the Sichuan-Yunnan Rhombic Block southwestern boundary, are concerned with the escaping movement of the Sichuan-Yunnan Rhombic Block. 相似文献