characteristics of recent crustal movement in the north section of north-south seismic belt

doi:10.3969/j.issn.0253-4967.2015.04.009

Abstract

Abstract:

Tectonic activity is intense and destructive earthquakes occur frequently in the northern section of the North-South Seismic Belt(NSSB). After the May 12, 2008 Wenchuan earthquake, the North-South Seismic Belt enters a new period of high seismicity. On July 22, 2013, the Minxian-Zhangxian earthquake occurred, which broke the 10-years seismic quiescence of magnitude 6 of the area, indicating an increasing trend of strong earthquakes in the region. Earthquake is the product of crustal movement. Understanding the dynamics of the process of crustal movement may provide basis for earthquake prediction. GPS measurement can provide high-precision, large-scale, quasi-real-time quantitative crustal movement data, that allows us to explore the evolution of crustal movement and its relationship with earthquake, thus providing the basis for determining the seismic situation. Since 2009, the density of mobile GPS measurement stations has significantly improved in the Chinese mainland, and moreover, the Wenchuan earthquake has brought about adjustment of the regional crustal deformation regime. So the introduction of the latest repeat GPS data is important for understanding the features of crustal movement in the northern section of the North-South Seismic Belt. In this paper, we obtained the GPS velocity field, fault profile and baseline time series and analyzed the dynamics of recent crustal movement in the northern section of the North-South Seismic Belt using the 1999a-2014a GPS data of mobile and continuous GPS measurement stations. The results show that: the Qilianshan Fault has a high strain accumulation background. There are locked portions on the Liupanshan Fault, especially in the region of Jingning, Pingling, Dingxi, Longxi. In 2004-2009a, the degree of locking of the Liupanshan Fault got higher. In 2009—2013a, crustal movement on the northern section of the North-South Seismic Belt weakened compared with 1999-2004, 2004-2009, and showed some features as follows: ① The velocity field weakened more markedly near the Qilian-Haiyuan-Liupanshan faults; ②The velocity decreased more significantly in the region north of Qilianshan-Haiyuan Fault than that of the south, resulting in enhanced thrust deformation on the Qilianshan Fault in 2009-2013a and the decreased sinistral shear deformation on the Qilianshan Fault and Haiyuan Fault; ③the velocity field decreased more remarkably at 50km west of Liupanshan Fault, compared to the east region, which led to the locked range on the Liupanshan Fault extending to the range of 100km near the fault zone during 2009-2013 from the previous locked range of 50km near the fault. The GPS baseline time series analysis also reveals a number of structural features in the region: Yinchuan Graben is continuing extending, and the extension in the west is stronger than that in the east. On the southern end of Yinchuan Graben, the deformation is very small.

Key words: north section of North-South Seismic Belt, crustal movement, GPS

摘要：

南北地震带北段构造活动强烈, 强震频发。近年来地震活动有增强的趋势, 震防形势严峻。利用GPS速度场、跨断层速度剖面以及基准站基线时间序列数据, 分析了近年来南北地震带北段地壳运动的动态特征。结果表明, 祁连山断裂具有较高的应变积累; 六盘山断裂存在闭锁, 静宁、平凉、陇西以及定西地区闭锁程度较深; 2004—2009年六盘山断裂闭锁程度加深。2009—2013年与1999—2004年、2004—2009年相比, 南北地震带北段地壳运动减弱, 且呈现出一些特征: 1)祁连山断裂—海原断裂—六盘山断裂附近减弱较显著; 2)祁连山-海原断裂以北区域较以南区域减弱显著, 造成了2009—2013年祁连山断裂挤压逆冲变形增强以及祁连山断裂和海原断裂带左旋剪切变形减弱; 3)六盘山断裂西侧50km以西区域较以东区域减弱显著, 导致六盘山断裂2009—2013年闭锁范围扩大到断裂带附近100km以内, 而此前六盘山断裂的闭锁范围在断裂带附近50km内。GPS基线时间序列分析还显示银川地堑正在持续拉张, 且西部拉张强度强于东部。

关键词: 南北地震带北段, 地壳运动, GPS速度场

CLC Number:

P315.2

WANG Jing, CHAI Chi-zhang, MA He-qing, ZENG Xian-wei, LI Guo-bin. characteristics of recent crustal movement in the north section of north-south seismic belt[J]. SEISMOLOGY AND GEOLOGY, 2015, 37(4): 1043-1054.

王静, 柴炽章, 马禾青, 曾宪伟, 李国斌. 近年来南北地震带北段地壳运动特征[J]. 地震地质, 2015, 37(4): 1043-1054.

References

国家地震局震害防御司. 1995. 中国历史强震目录(公元前23世纪—公元1911年)［Z］. 北京: 地震出版社.
Department of Earthquake Disaster Prevention, State Seismological Bureau. 1995. Catalogue of Chinese Historical Strong Earthquakes(23th Century B.C.—1911 A.D.)［Z］. Seismological Press, Beijing(in Chinese).
顾国华, 张晶, 王武星. 2005. 中国地壳运动观测网络GPS观测得到的地壳运动结果［J］. 测绘通报, 7: 1—7.
GU Guo-hua, ZHANG Jing, WANG Wu-xing. 2005. Crustal movement result from GPS observations of China crustal movement observation network ［J］. Bulletin of Surveying and Mapping, 7: 1—7(in Chinese).
韩月萍, 杨国华. 2006. 南北地震带水平形变及其动态特征［J］. 四川地震, 4(12): 15—18.
HAN Yue-ping, YANG Guo-hua. 2006. Horizontal deformation and dynamic characters of the North-South Seismic Belt ［J］. Earthquake Research in Sichuan, 4(12): 15—18(in Chinese).
刘经南, 施闯, 许才军, 等. 2001. 利用局域复测GPS网研究中国大陆块体现今地壳运动速度场［J］. 武汉大学学报(信息科学版), 26(3): 189—195.
LIU Jing-nan, SHI Chuang, XU Cai-jun, et al. 2001. Present-day crustal movement speed field of China continent block using local repeated GPS network ［J］. Geomatics and Information Science of Wuhan University, 26(3): 189—195(in Chinese).
马宗晋, 陈鑫连, 叶叔华, 等. 2001. 中国大陆区现今地壳运动的GPS研究［J］. 科学通报, 13: 1118—1120.
MA Zong-jin, CHEN Xin-lian, YE Shu-hua, et al. 2001. GPS study of present-day crustal movement in China ［J］. Chinese Science Bulletin, 13: 1118—1120(in Chinese).
牛之俊, 王敏, 孙汉荣, 等. 2005. 中国大陆现今地壳运动速度场的最新观测结果［J］. 科学通报, 50(8): 839—840.
NIU Zhi-jun, WANG Min, SUN Han-rong, et al. 2005. The latest observations of contemporary velocity field of crustal movement in China ［J］. Chinese Science Bulletin, 50(8): 839—840(in Chinese).
邵志刚, 张浪平. 2013. 南北地震带北段近期强震趋势研究［J］. 中国地震, 29(1): 26—36.
SHAO Zhi-gang, ZHANG Lang-ping. 2013. Study of strong earthquake recent trends on the northern segment of North-South Seismic Belt ［J］. Earthquake Research in China, 29(1): 26—36(in Chinese).
王敏, 沈正康, 牛之俊, 等. 2003. 现今中国大陆地壳运动与活动块体模型［J］. 中国科学(D辑), 33(增刊): 21—33.
WANG Min, SHEN Zheng-kang, NIU Zhi-jun, et al. 2003. Present-day crustal movement of Chinese mainland and active block model ［J］. Science China(Ser D), 33(suppl): 21—33(in Chinese).
王琪. 2003. 中国大陆现今地壳运动研究［J］. 地震学报, 25(5): 541—547.
WANG Qi. 2003. Current crustal movement in Chinese mainland ［J］. Acta Seismologica Sinica, 25(5): 541—547(in Chinese).
王琪, 张培震, 牛之俊, 等. 2001. 中国大陆现今地壳运动和构造变形［J］. 中国科学(D辑), 31(7): 529—536.
WANG Qi, ZHANG Pei-zhen, NIU Zhi-jun, et al. 2001. Present-day crustal deformation and tectonic deformation in China ［J］. Science China(Ser D), 31(7): 529—536(in Chinese).
武艳强, 江在森, 杨国华. 2007. 最小二乘配置方法在提取GPS时间序列信息中的应用［J］. 国际地震动态, 343(7): 99—103.
WU Yan-qiang, JIANG Zai-sen, YANG Guo-hua. 2007. The application of least square collocation in obtaining information from GPS time series ［J］. Recent Developments in World Seismology, 343(7): 99—103(in Chinese).
武艳强, 江在森, 杨国华, 等. 2012. 南北地震带北段近期地壳变形特征研究［J］. 武汉大学学报(信息科学版), 37(9): 1045—1048.
WU Yan-qiang, JIANG Zai-sen, YANG Guo-hua, et al. 2012. Deformation characteristics of north section of North-South Seismic Zone in recent period ［J］. Geomatics and Information Science of Wuhan University, 37(9): 1045—1048(in Chinese).
游新兆, 杨少敏, 王琪. 2012. 中国大陆地壳运动观测研究进展［J］. 地震, 32(2): 31—39.
YOU Xin-zhao, YANG Shao-min, WANG Qi. 2012. Progress of crustal movement observation and research in China ［J］. Earthquake, 32(2): 31—39 (in Chinese).
张培震, 王琪, 马宗晋. 2002. 青藏高原现今构造变形特征与GPS速度场［J］. 地学前缘, 9(2): 442—450.
ZHANG Pei-zhen, WANG Qi, MA Zong-jin. 2002. GPS velocity field and active crustal deformation in and around the Qinghai-Tibet plateau ［J］. Earth Science Frontiers, 9(2): 442—450(in Chinese).
张希, 王双绪, 王文萍, 等. 2006. 南北地震带近期地壳运动与构造变形特征［A］. 见: 中国地震学会第11次学术大会论文摘要集.
ZHANG Xi, WANG Shuang-xu, WANG Wen-ping, et al. 2006. The characteristics of recent crustal movement and tectonic deformation of North-South Seismic Belt ［A］. In: Proceedings of the 11th Academic Conference of China Seismological Society(in Chinese).
中国地震局震害防御司. 1999. 中国近代地震目录［Z］. 北京: 中国科学技术出版社. 1637.
Department of Earthquake Disaster Prevention, China Earthquake Administration. 1999. Catalogue of Chinese Modern Earthquakes ［Z］. China Science and Technology Press, BeiJing. 1637(in Chinese).
Bai D H, Unsworth M J, Meju M A, et al. 2010. Crustal deformation of the eastern Tibetan plateau revealed by magnetotelluric imaging ［J］. Nature Geoscrience, 3: 358—262.
Liang S M, Gan W J, Shen C M, et al. 2013. Three-dimensional velocity field of present-day crustal motion of the Tibetan plateau derived from GPS measurements ［J］. Journal of Geophysical Research, 118(10): 5722—5732.
Wang Q, Zhang P Z, Freymueller J T, et al. 2001. Present-day crustal deformation in China constrained by global positioning system measurements ［J］. Science, 294: 574—577.
Zhu W Y, Wang X Y, Cheng Z Y, et al. 2000. Crustal motion of Chinese mainland monitored by GPS ［J］. Science in China (Ser D), 43(4): 394—400.

[1]	CHANG Jin-long, GAN Wei-jun, ZHOU Chen, ZHU Cheng-lin, LIU Chang-sheng, YAO Cheng-yue. DISCUSSION ON STRAIN STATE AND SEISMOGENIC MECHANISM OF THE NORTH SECTION OF YILAN-YITONG FAULT ZONE [J]. SEISMOLOGY AND GEOLOGY, 2026, 48(1): 200-216.
[2]	LI Shu-peng, HU Min-zhang, ZHU Yi-qing, HAO Hong-tao, YIN Hai-tao, JIA Yuan, CUI Hua-wei, LU Han-peng, ZHANG Gang, WANG Feng-ji, LIU Hong-liang. GRAVITY CHANGES BEFORE THE PINGYUAN M_S5.5 EARTHQUAKE OF 2023 [J]. SEISMOLOGY AND GEOLOGY, 2024, 46(5): 1172-1191.
[3]	JIANG Feng-yun, JI Ling-yun, ZHU Liang-yu, LIU Chuan-jin. THE PRESENT CRUSTAL DEFORMATION CHARACTERISTICS OF THE HAIYUAN-LIUPANSHAN FAULT ZONE FROM INSAR AND GPS OBSERVATIONS [J]. SEISMOLOGY AND GEOLOGY, 2023, 45(2): 377-400.
[4]	HUA Jun, GONG Wen-yu, SHAN Xin-jian, WANG Zhen-jie, JI Ling-yun, LIU Chuan-jin, LI Yong-sheng. RESEARCH ON INTEGRATING INTERSEISMIC DEFORMATION RATE FIELDS OF MULTI-TRACK INSAR [J]. SEISMOLOGY AND GEOLOGY, 2022, 44(5): 1172-1189.
[5]	ZHANG Guo-qing, ZHU Yi-qing, LIANG Wei-feng. THE CRUSTAL DENSITY STRUCTURES AND ISOSTATIC ADDITIONAL STRESS AROUND THE FUBIANHE FAULT ON THE EASTERN MARGIN OF TIBET PLATEAU [J]. SEISMOLOGY AND GEOLOGY, 2022, 44(3): 578-589.
[6]	LIU Rui-chun, ZHANG Jin, GUO Wen-feng, CHEN Hui, ZHENG Ya-di, CHENG Cheng. STUDY ON THE RECENT DEFORMATION CHARACTERISTIC AND STRUCTURAL DEFORMATION MODEL OF THE SOUTH-EASTERN MARGIN OF ORDOS BLOCK [J]. SEISMOLOGY AND GEOLOGY, 2021, 43(3): 540-558.
[7]	DAI Cheng-long, ZHANG Ling, LIANG Shi-ming, ZHANG Ke-liang, XIONG Xiao-hui, GAN Wei-jun. PRESENT-DAY STRIKE-SLIP RATE AND ITS SEGMENTAL VARIATION OF THE TALAS-FERGHANA FAULT IN CENTRAL ASIA: INSIGHT FROM GPS GEODETIC OBSERVATIONS [J]. SEISMOLOGY AND GEOLOGY, 2021, 43(2): 263-279.
[8]	ZHU Shuang, LIANG Hong-bao, WEI Wen-xin, LI Jing-wei. SLIP RATES AND SEISMIC MOMENT DEFICITS ON MAJOR FAULTS IN THE TIANSHAN REGION [J]. SEISMOLOGY AND GEOLOGY, 2021, 43(1): 249-261.
[9]	TIAN Zhen, YANG Zhi-qiang, WANG Shi-di. MOMENT DEFICITS ON THE MAJOR FAULTS AND EARTHQUAKE HAZARD ASSESSMENT IN THE EASTERN HIMALAYAN SYNTAXIS [J]. SEISMOLOGY AND GEOLOGY, 2020, 42(1): 33-49.
[10]	CHEN Fu-chao, GUO Liang-qian, ZHENG Zhi-jiang. RESEARCH ON ACTIVITY OF ZHANGJIAKOU-BOHAI FAULT ZONE BASED ON GPS OBSERVATIONS [J]. SEISMOLOGY AND GEOLOGY, 2020, 42(1): 95-108.
[11]	WEI Cong-min, GE Wei-peng, ZHANG Bo. ESTIMATING THE LOWER CRUSTAL VISCOSITY OF THE WESTERN QINLING-SONGPAN TECTONIC NODE AND ITS ADJACENT AREAS BY USING LANDFORM MORPHOLOGY [J]. SEISMOLOGY AND GEOLOGY, 2020, 42(1): 163-181.
[12]	TANG Jing-tian, YANG Lei, REN Zheng-yong, HU Shuang-gui, XU Zhi-min. CHARACTERISTICS OF SATELLITE GRAVITY FIELD AND SEISMOGENIC MECHANISM IN THE LONGMENSHAN FAULT ZONE [J]. SEISMOLOGY AND GEOLOGY, 2019, 41(5): 1136-1154.
[13]	WEN Xiang, ZHOU Bin, SHI Shui-ping, QIN Jian, LI Jia-ning, HE Yan, YAN Chun-heng, LUO Yuan-peng. COMPREHENSIVE ANALYSIS OF RECENT GRAVITY AND CRUSTAL DEFORMATION IN NORTHWESTERN GUANGXI [J]. SEISMOLOGY AND GEOLOGY, 2019, 41(4): 927-943.
[14]	LIU Xiao-dong, SHAN Xin-jian, ZHANG Ying-feng, YIN Hao, QU Chun-yan. COSEISMIC DISPLACEMENT FIELD OF THE WENCHUAN EARTHQUAKE DERIVED FROM STRONG MOTION RECORDS AND APPLICATION IN SLIP INVERSION [J]. SEISMOLOGY AND GEOLOGY, 2019, 41(4): 1027-1041.
[15]	CHEN Yun-guo, HE Ping, DING Kai-hua, LI Shui-ping, WANG Qi. GEODETIC AND TELESEISMIC CONSTRAINTS ON SLIP DISTRIBUTION OF 2015 M_W6.4 PISHAN EARTHQUAKE [J]. SEISMOLOGY AND GEOLOGY, 2019, 41(1): 137-149.