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对山东省几个考古发掘遗址进行了地震考古研究,着重对其中的自然变形现象进行识别和分析。其中,在济南郊区的大辛庄商代遗址中甄别出非构造变形的现象;在章丘城子崖龙山文化层中识别出砂脉充填裂隙;在滨州秦皇台商周文化层中发现槽壁上砂脉和槽底密集分布的砂管;在临淄齐国故城城墙分别鉴别出构造和非构造成因裂隙;在日照尧王城见龙山-战汉时期文化层中平行分布的砂脉裂隙组;在滕州薛国故城城墙识别出典型共轭剪切裂隙。上述自然变形现象集中显现于春秋-战汉期及以前的文化层中,且多表现为砂脉等地震液化痕迹,显示相当时期所在地区可能处于地震相对活跃期,上述推断部分得到微观分析资料证实。 相似文献
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本文通过在河南新密、洛阳和南阳等地的实地考察,发现了一批存在于文化遗址中的自然变形现象,时代涉及新(旧)石器过渡期、东周到北魏时期等。其中在新密李家沟旧石器向新石器过渡期遗址发现三组裂缝,可代表三次构造变形活动。洛阳汉魏故城发现两类裂隙,一类穿切性较好,应为构造裂隙;另一类贯通性差,应为干燥收缩裂隙。南阳东周文化遗址发现两组充填裂隙,一组走向北东,一组走向北西,两组正交,被砂土充填,应为地震液化脉体,显示所在地区东周后有地震活动发生。初步研究表明,这些自然变形现象与当地区域构造方向具有一定的相关性,说明这些遗迹为史前地震事件记录的可能性较大,进一步分析判定这些自然变形现象的形成机制,对河南地震考古工作及历史地震研究的进一步开展具有重要的现实意义。 相似文献
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古遗址、古墓地发掘过程中的自然变形研究是反演或充实历史和史前变形历史记录的重要工作内容之一.近期我省地震部门会同省文物考古部门,对皖西霍山戴家院考古现场进行专题发掘调查,发现了与构造运动有关的地裂缝,其中充填有砂线、砂脉.初步研究显示包括两期变形,且均显示高速变形特征,代表两次地震事件.发生时代约相当于西周晚期和春秋中晚期,前者规模较大,含砂裂缝长轴方向平行于近侧的地震活动断裂方向.本次发现及初步分析填补了东部地区西周到春秋期自然变形事件研究空白. 相似文献
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GPS观测得到的地壳形变场通常包含有构造形变与非构造形变二类信息, 去除其中的非构造形变信息对于有效运用GPS数据研究构造形变场至关重要. 本文运用国际卫星对地观测资料及各类地球物理模型, 定量计算海潮、大气、积雪和土壤水、海洋非潮汐4项负荷效应造成的地壳非构造形变, 并以此研究和修正这些非构造形变对中国地壳运动观测网络GPS基准站位置时间序列的影响. 研究发现此4项负荷效应, 特别是大气、积雪和土壤水, 对于测站垂向位置的影响显著. 通过模型改正可以使测站垂向位置的RMS降低～1 mm, 占其总量的～11％. 对于垂向时间序列的周年项部分, 这一改正可降低其振幅的37％. 研究还表明经过地球物理模型改正和周年、半周年谐波拟合改正的时间序列比起仅经过周年、半周年谐波拟合改正的时间序列更为平滑, 表明地球物理模型改正对于消除非构造形变场的作用不是周年、半周年谐波拟合改正所能替代的. 相似文献
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汶川大地震中成都地区液化及其震害现象较为显著.通过现场调查和工程地质资料分析,成都地区的液化特点为:液化带主要集中都江堰市液化在烈度Ⅵ、Ⅶ、Ⅷ、X和X度区均有出现,但Ⅶ度区最为集中液化喷水高度多在1-3m之间,最高一处超过10m液化场地喷出物涵盖了多种土类,约67％为粉细砂,且有卵砾石,约占11％液化带普遍伴随地裂缝,... 相似文献
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Seismites in the Dasheng Group: New evidence of strong tectonic and earthquake activities of the Tanlu Fault Zone 总被引：1，自引：0，他引：1
HongShui Tian Antonius Johannes Van Loon HuaLin Wang ShenHe Zhang JieWang Zhu 《中国科学:地球科学(英文版)》2016,59(3):601-618
More than 80 layers of seismites were recognized from the Early Cretaceous Dasheng Group in the Mazhan and Tancheng graben basins in the Tanlu Fault Zone, eastern China. The responsible seismic events took place about 110–100 Ma in the Early Cretaceous. The fault zone was affected at the time by strong tectonics, due to tension-related stretching and scattered squeezing by strike-slip faults. These tectonic activities induced a series of strong earthquakes with Richter magnitudes(M) of 5–8.5. The earthquakes affected saturated or semi-consolidated flood and lake sediments, and produced intra-layer deformations by several processes, including liquefaction, thixotropy, drop, faulting, cracking, filling and folding, which resulted in the formation of various soft-sediment deformation structures, such as dikes and veins of liquefied sand, liquefied breccias, liquefied homogeneous layers, load structures, flame structures, ball-and-pillow structures, boudinage, diapirs, fissure infillings, a giant conglomerate wedge, and syn-sedimentary faults. The seismites are new evidence of tectonic and seismic activities in the Tanlu Fault Zone during the Early Cretaceous; the series of strong seismic events that can be deduced from them must be considered as a response to the destruction of the North China Craton. 相似文献
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Anqiu-Juxian Fault is an important fault in the Tanlu fault zone, with the largest seismic risk, the most recent activity date and the most obvious surface traces. It is also the seismogenic fault of the Tancheng M8 1/2 earthquake in 1668. There are many different views about the southern termination location of surface rupture of the Tancheng earthquake and the Holocene activity in Jiangsu segment of this fault. Research on the latest activity time of the Jiangsu segment of Anqiu-Juxian Fault, particularly the termination location of surface rupture of the Tancheng earthquake, is of great significance to the assessment of its earthquake potential and seismic risk.
Based on trench excavation on the Jiangsu segment of Anqiu-Juxian Fault, we discuss the time and characteristics of its latest activity. Multiple geological sections from southern Maling Mountain to Chonggang Mountain indicate that there was an ancient seismic event occurring in Holocene on the Jiangsu segment of Anqiu-Juxian Fault. We suggest the time of the latest seismic event is about(4.853±0.012)~(2.92±0.3)ka BP by dating results. The latest activity is characterized by thrust strike-slip faulting, with the maximum displacement of 1m. Combined with the fault rupture characteristics of each section, it is inferred that only one large-scale paleo-earthquake event occurred on the Jiangsu segment of Anqiu-Juxian Fault since the Holocene.
The upper parts of the fault are covered by horizontal sand layers, not only on the trench in the west of Chonggang mountain but also on the trench in Hehuan Road in Suqian city, which indicates that the main part of the Jiangsu segment of Anqiu-Juxian Fault was probably not the surface rupture zone of the 1668 Tancheng M8 1/2 earthquake.
In short, the Jiangsu segment of Anqiu-Juxian Fault has experienced many paleo-earthquake events since the late Pleistocene, with obvious activity during the Holocene. The seismic activities of the Jiangsu segment of Anqiu-Juxian Fault have the characteristics of large magnitude and low frequency. The Jiangsu segment of Anqiu-Juxian Fault has the deep tectonic and seismic-geological backgrounds of big earthquakes generation and should be highly valued by scientists. 相似文献
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EARTHQUAKE-CAUSED SEISMIC VOLCANIC ROCKS AND THIXOTROPIC DEFORMATION OF SOFT SEDIMENTS IN THE UPPER CRETACEOUS SHIJIATUN MEMBER,JIAOZHOU CITY 
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下载免费PDF全文 A lot of seismic volcanic rocks and strong earthquake-induced thixotropic deformation structures in soft mud-sandy sediments(seismites)were identified from the Upper Cretaceous Shijiatun Member of the Hongtuya Formation for the first time in Jiaozhou City of the Zhucheng Sag, eastern China. Seismic volcanic rocks are volcanic rocks with co-seismic deformation structures which were produced by major earthquakes destroying volcano ejecta. Seismites are sediment layers with soft-sediment deformation structures formed by strong earthquake triggering saturated or semi-consolidated soft sediments to produce liquefaction, thixotropy, faults, cracks and filling and so forth. The Shijiatun Member of the Hongtuya Formation mainly consists of basaltic volcano rocks interbedded with mud-sandy(muddy sand and sandy mud)deposition layers of the river-lake facies. In the Shijiatun Member, main types of seismic volcanic rocks are shattered basalts with co-seismic fissures and seismic basaltic breccias. The thixotropic deformations of soft mud-sandy sediments mainly include thixotropic mud-sandy veins and thixotropic mud-sandy layers with tortuous boundaries. Under the strong earthquake action, saturated mud-sandy sediments could not be liquefied, instead resulting in thixotropy, i.e. their texture can be damaged and their flow-ability or rheology becomes strong. Because basaltic volcano rocks were damaged(shattered, seismic broken), a major earthquake can lead to thixotropic mud-sandy sediments flowing along seismic fissures in basalts, resulting in the formation of deformation structure of thixotropic veins, and boundaries between volcano rock and mud-sand layer became quite winding. Under the koinonia of gravity and vibration force, seismic breccia blocks sunk into thixotropic mud-sandy layers, resulting in the formation of inclusions of thixotropic mud-sandy sediments. Seismic intensity reflected by these strong earthquake records during the end stage of the Late Cretaceous was about Ⅶ to more than X degrees. The Shijiatun Member is mainly distributed in the south of the Baichihe fault in the northern Zhucheng Sag, and the fault has generated many strong tectonic and earthquake activities at the end of the late Cretaceous, also provided the channel for intrusion and eruption of basaltic magma then. At the end of the late Cretaceous, intermittent intrusion and eruption of basaltic magma took place along the Baichihe fault, meanwhile the volcano earthquakes took place or tectonic earthquakes were generated by the Baichihe fault which caused the deformation of the volcano lava and underlying strata of red saturated muddy-sand, resulting in the formation of various seismo-genesis deformations of volcanic rocks interbedded with mud-sandy sediment layers. Therefore, strong seismic events recorded by them should be responses to strong tectonic taphrogenesis of the Zhucheng Sag and intense activity of the Baichihe fault in the end of Late Cretaceous. In addition, these seismogenic deformation structures of rock-soil layers provide new data for the analysis of the failure effect produced by seismic force in similar rock-soil foundations. 相似文献
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2022年1月8日门源M6.9地震造成山丹明长城局部破坏。为研究此次地震作用下夯土城墙的动力响应与破坏特征,基于地震现场考察结果,采用振幅等效处理后的记录地震波为输入地震动,开展双向地震荷载作用下夯土城墙的动力响应数值分析,研究不同位置测点的最大位移、峰值加速度与墙体应力分布特征,探讨地震导致夯土城墙破坏的主要内因。研究结果表明：双向地震荷载作用下,墙体位移和峰值加速度(PGA)随着高度的增加逐渐增加,但距墙体底部0.5 m高度范围内PGA放大效应不明显,最大位移、加速度均出现在墙体顶部裂缝位置处;水平地震荷载作用下墙体的地震动响应更为显著;墙体的最大主应力、最大剪应力均出现在有裂缝处的底端掏蚀悬空部位,墙体裂缝、夯筑搭接、掏蚀悬空处应力集中明显;裂缝对夯土城墙的地震动放大效应在一定高度范围内表现为弱化作用,但随高度增加逐渐过渡为强化作用;裂缝可显著增强墙体顶部地震动响应,可能是本次地震诱发城墙破坏的主要内因。研究成果可为古城墙遗址的加固修缮提供科学指导。 相似文献
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本文着重研究了近代工程施工中发现的大量震害遗迹, 诸如断层、裂缝、喷水冒砂现象, 诱发滑坡和坠入地震断裂带中的木炭与文物.又经考古研究和 C14鉴定属明代之物, 证实这条在极震区延伸大于70公里的破裂带就是这次大地震极震区地面破裂带. 相似文献
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以甘肃省平凉市的典型黄土塬斜坡为原型,开展含裂隙黄土塬边斜坡与不含裂隙黄土塬边斜坡的振动台对比模型试验,研究不同强度地震作用下两种黄土斜坡的变形失稳特征。结果表明:两种不同结构的斜坡在不同强度地震作用下的破坏特征显著不同,裂隙的存在降低了含裂隙斜坡的抗震稳定性。随着输入地震波幅值的增加,含裂隙斜坡的变形破坏过程为:坡顶裂隙处先后发生裂隙前缘崩塌、坡面溜土、临空面方向大位移、坡面中部和坡脚鼓胀、剪切滑移、发生多级滑动,同时坡体后缘产生新的拉张裂隙;无裂隙斜坡的破坏过程为:坡顶形成拉张裂缝、坡面溜土、坡脚鼓胀、发生单级滑动。两种结构边坡的变形破裂包括倾倒—拉裂与剪切—滑移两种模式,斜坡的变形演化是两种模式相互作用的结果。 相似文献
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Liquefaction macrophenomena in the great Wenchuan earthquake 总被引：3，自引：2，他引：1
Longwei Chen Xiaoming Yuan Zhenzhong Cao Longqing Hou Rui Sun Lin Dong Weiming Wang Fanchao Meng Hongjuan Chen 《地震工程与工程振动(英文版)》2009,8(2):219-229
On May 12, 2008 at 14:28, a catastrophic magnitude M 8.0 earthquake struck the Sichuan Province of China.The epicenter was located at Wenchuan (31.00°N, 103.40°E). Liquefaction macrophenomena and corresponding destruction was observed throughout a vast area of 500 km long and 200 km wide following the earthquake. This paper illustrates the geographic distribution of the liquefaction and the relationship between liquefaction behavior and seismic intensity, and summarizes the liquefaction macrophenomena, including sandboils and waterspouts, ground subsidence, ground fissures etc., and relevant liquefaction features. A brief summary of the structural damage caused by liquefaction is presented and discussed. Based on comparisons with liquefaction phenomena observed in the 1976 Tangshan and 1975 Haicheng earthquakes, preliminary analyses were performed, which revealed some new features of liquefaction behavior and associated issues arising from this event. The site investigation indicated that the spatial non-uniformity of liquefaction distribution was obvious and most of the liquefied sites were located in regions of seismic intensity Ⅷ. However, liquefaction phenomena at ten different sites in regions of seismic intensity Ⅵ were also observed for the first time in China mainland. Sandboils and waterspouts ranged from centimeters to tens of meters, with most between 1 m to 3 m. Dramatically high water/sand ejections,e.g., more than 10 m, were observed at four different sites. The sand ejections included silty sand, fine sand, medium sand,course sand and gravel, but the ejected sand amount was less than that in the 1976 Tangshan earthquake. Possible liquefaction of natural gravel soils was observed for the first time in China mainland. 相似文献
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Rosa Lasaponara Ruixia Yang Fulong Chen Xin Li Nicola Masini 《Surveys in Geophysics》2018,39(6):1303-1322
This paper provides a state of the art of the use of declassified satellite Corona for archaeological application and deals with the use of historical archives of Corona and aerial photographs for detecting ancient hidden cultural relics that may be completely lost in the modern landscape veiled by current land uses and land covers. Geospatial analysis is adopted to identify, extract and map the subtle archaeological features and cultural landscape of the lost Han–Wei Forbidden City in the Henan Province (China). It was one of the most important cities of ancient China, served as the capital for a long period, from the Eastern Zhou (2600 BP, Zhou Dynasty) to the Eastern Han and Wei Dynasties (1900–1500 BP). Outputs from our investigations clearly provided evidence of numerous buried structures of potential archaeological interest that were compared with historical documentation and excavations carried out in the area. The geospatial analysis, applied both to aerial photograph and to Corona pictures, enabled us to discover a number of unknown sub-palaces and structures, thus providing new insights for this important archaeological area. 相似文献
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Yao Daquan Shuo Zhi Shen Xiaoqi Chen Anguo Zheng Yingping Zheng Haigang Li Lingli 《中国地震研究》2010,24(3):363-370
During an excavation survey to the Daijiayuan vestige of the Western Zhou Dynasty-Late Spring and Autumn Period at Huoshan in Western Anhui,a ground crack related to tectonic movement and filled with silty fine sand was found. This phenomenon was initially confirmed to be due to seismic liquefaction. Many microscopic seismic relics,such as load structure,flow structure,cutoff plane and flotation of organic matter were found in the directional microscopic analysis of deformation. These discoveries and cognitions prove that there were two earthquake events taking place in the Western Zhou Dynasty-Late Spring and Autumn Period in this area. Above-mentioned works enrich and develop the research methods to identify prehistoric earthquake event in eastern China area to a certain extent. 相似文献
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城市震害预测中设定地震的确定问题 总被引：2，自引：0，他引：2
提出了一个确定震害预测中设定地震的方法,包括：确定贡献量最大的潜在震源区、潜在震源区内贡献量最大的震级档和设定地震的构造位置等。以福建省泉州市为例,获得５０年超赵概率６３％、１０％和２％等３个概率水平下的设定地震。本文给出的设定地震方法纵使了确定论方法和概率论方法的优点,有助于地震危险性分析方法的发展。 相似文献