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Recurrence Characteristics of Major Earthquakes in the Tangshan area,North China

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 254-271,269-271+267-268页

作者： LIU Kang qu guosheng CHEN Jianqiang WANG Weiguo NING Baokun Institute of Geology China Earthquake Administration National Earthquake Response Support Service China University of Geosciences Tangshan Earthquake Administration

The Tangshan area lies in the North China plain where an Ms 7.8 earthquake occurred in 1976, which is associated with a hidden active fault. To reveal the recurrence characteristics of major quakes in this area over a relatively long time, we have conducted a comprehensive study using geological investigations, shallow seismic exploration, boreholes, trench observations and geological dating. Five paleoearthquakes were recognized in a 6.4m-deep trench west to the Tangshan Asylum. Among them, the former three events occurred between 56.78 ＋ 4.83ka and 89.39 ~ 7.60 ka, and the fourth event occurred around 6.9 ka, respectively, and then followed by the fifth in 1976. Seven boreholes were deployed crossing the ground fissure formed by the 1976 Tangshan earthquake at the site of No. 10 Middle School, where we have identified 25 liquefaction events in the boreholes TZC6-5 and 6-7. By the comprehensive analysis of the trench, the liquefaction events from the boreholes and the depth-time curves of drill cores, we suggest a new recurrence model of major quakes in this area. It is not a constant recurring cycle since 210 ka, instead consisting of six alternating seismically quiet and active stages. Of them, stage I （〉177 ka） was a quiescent period in seismicity, stage II （from 143 ka to 177 ka） was an active one, stage III （from 102 ka to 143 ka） was quiescent again, stage IV （from 56 ka to 102 ka） had many quakes, stage V （from 6.9 ka to 56 ka） became quiet, and stage VI （from 6.9 ka to now） was the beginning of a new seismically active period.

关键词： paleoearthquake recurrence trench borehole Tangshan earthquake

Fractal and Multifractal Propertiesof the Spatial Distribution of Natural Fractures——Analyses and Applications

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Acta Geologica Sinica(English Edition) 1999年第4期73卷 477-487页

作者： XU Jiandong qu guosheng Robert D. JACOBI Institute of Geology China Seismological Bureau Beijing 100029 PRC Department of Geology State University of New York at Buffalo USA

The Cantor's dust theory is applied to investigate the scaling properites of the spatial distribution of natural fractures obtained from detailed scanline surveys of 27 field sites in the Appalachian Plateau of western New York, USA. The results obtained in this study indicate: 1) fracture spacing is characterized by fractal and multifractal properties. On small scales analyses yield an average fractal dimension of 0.15, which suggests a very high degree of clustering. In contrast, on large scales, fractures tend to be more regular and evenly distributed with an average fracture dimension of 0.52; 2) fractal dimension varies with different sets in different orientations, which can be attributed to interactions between pre-existing fractures and younger ones, as well as variations of the intensity of the stresses under which the fractures were formed; 3) a time sequence of fracture set formation can be proposed based on fractal and multifractal analyses, which consists of (from old to young): N-S, NW, ENE, and NE-striking sets. This time sequence is confirmed by the study of the abutting relationships of different fracture sets observed in the field.

关键词： fractal multifractal fracture

Structural Characteristics and Formation Mechanism in the Micangshan Foreland,South China

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Acta Geologica Sinica(English Edition) 2009年第1期83卷 81-91页

作者： XU Huaming LIU Shu qu guosheng LI Yanfeng SUN Gang LIU Kang Institute of Geology China Earthquake Administration Beijing 100029 China Southwestern Division Company ofSINOPEC Deyang Sichuan 618000 China National Earthquake Response Support Service China Earthquake Administration Beijing 100049 China

Lying at the junction of the Dabashan, Longmenshan and Qinling mountains, the Micangshan Orogenic Belt coupled with a basin is a duplex structure and back-thrust triangular belt with little horizontal displacement, small thrust faults and continuous sedimentary cover. On the basis of 3D seismic data, and through sedimentary and structural research, the Micangshan foreland can be divided into five subbelts, which from north to south are： basement thrust, frontal thrust, foreland depression-back-thrust triangle, foreland fold belt or anticline belt, and the Tongjiang Depression. Along the direction of strike from west to east, the arcuate structural belt of Micangshan can be divided into west, middle and east segments. During the collision between the Qinling and Yangtze plates, the Micangshan Orogenic Belt was subjected to the interaction of three rigid terranes： Bikou, Foping, and Fenghuangshan （a.k.a. Ziyang） terranes. The collision processes of rigid terranes controlled the structural development of the Micangshan foreland, which are：（a） the former collision between the Micangshan-Hannan and Bikou terranes forming the earlier rudiments of the structure; and （b） the later collision forming the main body of the structural belt. The formation processes of the Micangshan Orogenic Belt can be divided into four stages：（1） in the early stage of the Indosinian movement, the Micangshan-Hannan Rigid Terrane was jointed to the Qinling Plate by the clockwise subduction of the Yangtze Plate toward the Qinling Plate; （2） since the late Triassic, the earlier rudiments of the Tongnanba and Jiulongshan anticlines and corresponding syncline were formed by compression from different directions of the Bikou, Foping and Micangshan-Hannan terranes; （3） in the early stage of the Himalayan movement, the Micangshan-Hannan Terrane formed the Micangshan Nappe torwards the foreland basin and the compression stresses were mainly concentrated along both its flanks, whereas the Micangshan-Han

关键词： arcuate structure Bikou duplex structure Foping Micangshan-Hannan orogenic belt,terrane Sichuan Yangtze Plate

The Orogeny in the Altaides

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Acta Geologica Sinica(English Edition) 1993年第1期67卷 1-15页

作者： qu guosheng Institute of Geology, State Seismological Bureau, Beijing and He Guoqi Department of Geology, Peking University, Beijing Liu Linqun Institute of Geology State Seismological Bureau Beijing China

Studies of the deformation styles, formation types and isotopic age data indicate that the Altaides has successively experienced 5 stages of orogeny: (1) the Kanas orogeny forming the angular unconformity between the Baihaba Formation (O_3) and the Habahe Group (Z-O_2); (2) the Daqiao orogeny (S_3-D_(1-2) giving rise to the early Hercynian quasi-aulacogen extensional continental crust of the area; (3) the Altay orogeny (middle-late Hercynian) leading to the oblique intracontinentai collision and the formation of large shear arc-shaped thrust system and representing a strong orogeny stage; (4) the pan-Altay orogeny (latest Hercynian-Indosinian) resulting in the uplifting and erosion of the mountains as a whole; (5) the Himalayan movement causing the rejuvenation of fault systems and block uplift of the Aitaides since the Cenozoic.

关键词： Altaides orogeny

Characterization of three novel snoRNAs from Schizosaccharomyces pombe implies the structural and functional diversity of box H/ACA snoRNA family

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Chinese Science Bulletin 2003年第21期48卷 2320-2327页

作者： qu guosheng, ZHOU Hui, YU Chuanhe, CHEN Xiao & qu Lianghu Key Laboratory of Gene Engineering of the Ministry of Education, Bio-technology Research Center, Zhongshan University, Guangzhou 510275, China Correspondence should be addressed to qu Lianghu (e-mail: lsbrc04@ ***) Key Laboratory of Gene Engineering of the Ministry of Education Biotechnology Research Center Zhongshan University Guangzhou China

Site-specific pseudouridylations of rRNAs and snRNAs are directed by small guide RNAs that usually pos-sess conserved H and ACA motifs and the consensus secon-dary structure consisting of hairpin-hinge-hairpin-tail. In this study, through screening cDNA library, three novel box H/ACA snoRNAs, termed SP12, SP16 and SP20, have been identified from fisson yeast Schizosacchromyces pombe. Each of the small RNAs possesses an ACA-like motif and exhibits secondary structures containing two or three large hairpin- like domains. Although the box H is noncanonical, SP20 can be potentially folded into a typical box H/ACA snoRNA-like structure and is predicted to guide two pseudouridylations, U1208 and U1053, on 18S rRNA. In contrast, SP12 and SP16 display different structures from SP20 and have no antisense elements to rRNAs or snRNAs. Obviously, they are new members of orphan guide snoRNAs whose functions remain elusive. The genes encoded for SP12 and SP16 are both lo-cated in long intergenic regions between protein-coding genes. A post-transcriptional processing for SP16 precursor was demonstrated. Interestingly, SP20 gene is nested inside a very hypothetical ORF, but transcribed in a reverse sense. Northern and RT-PCR analyses could not detect the tran-script from the hypothetical ORF, and therefore exclude the expression of the spurious gene. This is the first example that a genetic locus predicted for protein-coding gene actually encodes a small non-messenger RNA in S. pombe.

关键词： RNA 核糖核酸脱氧核糖核酸 DNA 蛋白质

Exploration and Research of Deep Crustal Structures in the Zhangzhou Basin and Its Vicinity

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Earthquake Research in China 2006年第4期20卷 412-425页

作者： Zhu Jinfang Fang Shengming Zhang Xiankang qu guosheng Huang Zonglin Zhang Chengke Zhao Jinren Earthquake Administration of Fujian Province Fuzhou 350003 China Geophysical Exploration Center CEA Zhengzhou45002.China National Earthquake Response Support Service CEA Beijing 100049 China

The Zhangzhou basin is located at the middle section of the southeast coast seismic zone of the mainland of China. Using high-resolution refraction and wide-angle reflection/refraction seismic profiling of Zhangzhou basin and its vicinity, we have obtained the crustal geometric structure and velocity structure as well as the geometric configuration and structural relationship between the deep and shallow fractures. The results show that the crust in the region is divided into the upper crust and lower crust. The thickness of the upper crust is 16.5km- 18.8km, and that of the lower crust is 12.0km- 13.0km. The upper crust is further divided into an upper and lower section. In the lower section of the upper crust, there is a low-velocity layer with a velocity of about 6.00km/s; the depth of the top surface of the low-velocity layer is about 12.0km, and the thickness is about 5.0km. The lower crust is also divided into an upper and lower section. The depth of Moho is 29.0km- 31 .8km There are 6 normal faults in the shallow crust in this region, and most of them extend downwards to a depth of less than 4kin, the maximum depth is about 5km. Below the shallow normal faults, there is a conjectural high-dip angle deep fault zone. The fault zone extends downwards till the Moho and upwards into the low-velocity layer in lower section of the upper crust. The deep and shallow faults are not tectonically connected. The combination character of deep and shallow structures in the Zhangzhou basin indicates that the Jiulongjiang fault zone is a deep fault zone with distinct characteristics and a complex deep and shallow structure background. The acquisition of deep seismic exploration results obviously enhanced the reliability of explanation of deep-structural data and the exploration precision of the region. The combination of deep and shallow structures resulted in uniform explanation results. The delamination of the crust and the characteristic of the structures are more pr

关键词： High-resolution refraction Deep seismic wide-angle reflection/refraction Crust-mantle structure Deep structure

Exploration and Study of Deep Crustal Structure in the quanzhou Basin and Its Adjacent Area

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Earthquake Research in China 2006年第3期20卷 305-315页

作者： Zhu Jinfang Fang Shengming Zhang Xiankang qu guosheng Huang Zonglin Hong Xing Liu Baojin Yang Zhuoxin Duan Yonghong Earthquake Administration of Fujian Province Fuzhou 350003 China Geophysical Exploration Center CEA Zhengzhou 450002 China National Earthquake Response Report Service Beijing 100049 China

The quanzhou basin and its adjacent areas locate in the middle of the southeastern coast seismic belt on the Chinese mainland. The very fine geometry structure of this area from near ground to Moho interface and the relationship between the deep and shallow faults are obtained based on deep seismic reflection profiling. This profile is the first deep seismic reflection profile in this area and it indicates that the crust can be divided into the upper crust and the lower crust and the thickness of crnst is from 29.5 km to 31 km in this area. The upper crust and the lower crust can be also divided into two layers. There are shallow normal faults developed in the upper crust and extending to the depth from 6 km to 12 kin. The angle of those listric faults decreases with depth and the faults joint into the C1 interface （detachment surface）. There is a high angle fault under the Yong＇an-Jinjiang fault belt which cuts off the interface of the upper crust and the lower crust and the Moho interface. Although there is no connection between the shallow and the deep faults, it offers deep structural environment for moderate and strong earthquake because of the deep high angle fault. This exploration result improves the reliability and precision of explanation of deep crustal structure in this area. The pull-apart and listric normal fault model indicates that the upper crust structure accords to the dynamic process of Taiwan Straits. This is helpful for seismicity estimation of quanzhou and its adjacent area and important for obtaining more of the dynamic process of the southeast coast seismic belt.

关键词： Deep seismic reflection Crust-mantle structure Deep structure

基于风险和应急准备能力评估的应急救援能力建设

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安全 2019年第5期40卷 1-6页

作者：曲国胜中国地震应急搜救中心

为提升我国应对综合自然灾害的应急响应与救援能力,笔者首先指出我国目前在应急准备能力评估和应急救援能力建设方面存在的主要问题;然后以地震为例,提出应急准备能力评估的指标体系框架、指标分类及评价方法,通过评估找出现存能力差距... 详细信息

为提升我国应对综合自然灾害的应急响应与救援能力,笔者首先指出我国目前在应急准备能力评估和应急救援能力建设方面存在的主要问题;然后以地震为例,提出应急准备能力评估的指标体系框架、指标分类及评价方法,通过评估找出现存能力差距,开展基于风险评估和应急准备能力评估的应对综合自然灾害的救援能力建设。研究表明:开展基于风险和应急准备能力评估的救援能力建设能实现重特大自然灾害快速有效响应与指挥调度能力,极大提升我国重特大自然灾害的应对能力。

关键词：综合自然灾害风险应急准备能力评估救援能力建设

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福建东南沿海第四纪盆地构造沉降

第四纪研究 2009年第3期29卷 633-643页

作者：张路曲国胜陈建强中国地震局地壳应力研究所北京100085 中国地震应急救援中心北京100049 中国地质大学北京100083

利用福建东南沿海地区城市活断层探测的研究资料,重新确认了福州、泉州和漳州盆地的断层组合与第四纪沉积。研究区内晚更新世"福州海侵"产生的炭质淤泥沉积现代高程的分析对比表明,晚更新世以来该区地壳发生不均匀隆升,而这些盆地相对... 详细信息

利用福建东南沿海地区城市活断层探测的研究资料,重新确认了福州、泉州和漳州盆地的断层组合与第四纪沉积。研究区内晚更新世"福州海侵"产生的炭质淤泥沉积现代高程的分析对比表明,晚更新世以来该区地壳发生不均匀隆升,而这些盆地相对于研究区内其他地区发生沉降。断层的静态位错理论研究认为,正断层深部活动引发地表的沉降,该区断裂的深部正断层活动是盆地沉降的重要因素。盆地的发展演化可划分为晚更新世以前的断陷阶段,和其间或其后的拗陷沉积阶段。

关键词：福建东南沿海晚更新世海侵盆地构造沉降断裂深部活动