基岩断面宇宙成因核素暴露定年:重建正断层古地震序列

doi:10.3969/j.issn.0253-4967.2018.05.014

摘要/Abstract

摘要： 正断层基岩断面可以连续地记录大地震位移累积的过程以及地震事件序列。该地震序列发生的时间与地震位移导致的基岩断面的暴露时间呈正相关。因此，通过测定断面基岩表层的宇宙成因核素浓度，可获得过去大地震发生的次数、时间和滑动量。目前研究工作中广泛选用灰岩的宇宙成因核素³⁶Cl测年方法，最佳采样基岩断面的高度距地表15～20m。选择采样剖面时，需确保基岩表面记录的是构造事件而并非地貌剥蚀过程，断面平直新鲜。基本采样策略是，在崩积楔之上和之下平行断层滑动方向连续采集一系列基岩样品，单件样品的长×宽×厚约15cm×10cm×3cm。基于样品的宇宙成因核素³⁶Cl和稀土元素-钇（REE-Y）浓度随着样品距地表高度的变化情况，识别出强震次数及其发生时间范围，然后运用数值模型模拟³⁶Cl剖面来获得最可能的强震事件发生时间和滑动量以及相应的误差。

关键词: 正断层, 基岩断面, 宇宙成因核素, 长周期地震记录, 断层滑动速率

Abstract: The bedrock scarps are believed to have recorded the continuous information on displacement accumulation and sequence of large earthquakes. The occurrence timing of large earthquakes is believed to be correlated positively with the exposure duration of bedrock fault surfaces. Accordingly, cosmogenic nuclides concentration determined for the bedrock footwall can offer their times, ages, and slip over long time. In general, multiple sites of fault scarps along one or even more faults are selected to carry out cosmogenic nuclide dating in an attempt to derive the temporal and spatial pattern of fault activity. This may contribute to explore whether earthquake occurrence exhibits any regularity and predict the timing and magnitude of strong earthquakes in the near future. Cosmogenic nuclide ³⁶ Cl dating is widely applied to fault scarp of limestone, and the height of fault scarp can reach as high as 15~20m. It is strongly suggested to make sure the bedrock scarp is exhumed by large earthquake events instead of geomorphic processes, based on field observation, and data acquired by terrestrial LiDAR and ground penetration radar (GPR). In addition, it is better for the fault surface to be straight and fresh with striations indicating recent fault movement. A series of bedrock samples are collected from the footwall in parallel to the direction of fault movement both above and below the colluvium, and each of them is~15cm long,~10cm wide, and~3cm thick. The concentrations of both cosmogenic nuclide ³⁶ Cl and REE-Y determined from these samples vary with the heights in parallel to fault scarps. Accordingly, we identify the times of past large earthquakes, model the profile of ³⁶ Cl concentration to seek the most realistic one, and determine the ages and slip of each earthquake event with the errors. In general, the errors for the numbers, ages, and slips of past earthquake events are ±1-2, no more than ±0.5-1.0ka, and ±0.25m, respectively.

Key words: normal faulting, bedrock fault scarp, cosmogenic nuclides, long-period earthquake record, fault slip rates

中图分类号:

P597

张金玉, 刘静, 王恒, 石许华, 姚文倩, 徐晶, 徐心悦. 基岩断面宇宙成因核素暴露定年:重建正断层古地震序列[J]. 地震地质, 2018, 40(5): 1149-1169.

ZHANG Jin-yu, ZENG Jing, WANG Heng, SHI Xu-hua, YAO Wen-qian, XU Jing, XU Xin-yue. COSMOGENIC NUCLIDES EXPOSURE DATING FOR BEDROCK FAULT SCARP: RECONSTRUCTING THE PALEOEARTHQUAKE SEQUENCE[J]. SEISMOLOGY AND GEOLOGY, 2018, 40(5): 1149-1169.

参考文献

邓起东. 2002. 城市活动断裂探测和地震危险性评价问题［J］. 地震地质, 24(4):601-605.
DENG Qi-dong, 2002. Exploration and seismic hazard assessment of active faults in urban areas［J］. Seismology and Geology, 24(4):601-605(in Chinese).
邓起东, 汪一鹏, 廖玉华, 等. 1984. 断层崖崩积楔及贺兰山山前断裂全新世活动历史［J］. 科学通报, (9):557-560.
DENG Qi-dong, WANG Yi-peng, LIAO Yu-hua, et al. 1984. The Holocene activities of Helan mountain piedmont fault revealed by fault scarps and colluvial wedge［J］. Chinese Science Bulletin, (9):557-560(in Chinese).
邓起东, 张培震. 2000. 史前古地震的逆断层崩积楔［J］. 科学通报, 45(6):650-655.
DENG Qi-dong, ZHANG Pei-zhen, 2000. Colluvial wedges associated with pre-historical reverse faulting paleoearthquakes［J］. Chinese Science Bulletin, 45(6):650-655(in Chinese).
何宏林, 魏占玉, 毕丽思, 等. 2015. 利用基岩断层面形貌定量特征识别古地震:以霍山山前断裂为例［J］. 地震地质, 37(2):400-412. doi:10.3969/j.issn.0253-4967.2015.02.005.
HE Hong-lin, WEI Zhan-yu, BI Li-si, et al. 2015. Identify paleo-earthquakes using quantitative morphology of bedrock fault surface:A case study on the Huoshan piedmont fault［J］. Seismology and Geology, 37(2):400-412(in Chinese).
刘静, 徐锡伟, 李岩峰, 等. 2007. 以海原断裂甘肃老虎山段为例浅析走滑断裂古地震记录的完整性:兼论古地震研究中的若干问题［J］. 地质通报, 26(6):650-660.
LIU-ZENG Jing, XU Xi-wei, LI Yan-feng, et al. 2007. On the completeness of paleoseismic records of strike-slip faults:An example from the Laohushan segment of the Haiyuan Fault in Gansu, China, with a discussion of several problem in the paleoearthquake study［J］. Geological Bulletin of China, 26(6):650-660(in Chinese).
马严, 武颖, 庞建章, 等. 2015. 宇宙成因核素²¹Ne测年原理和应用［J］. 地震地质, 37(1):242-255. doi:10.3969/j.issn.0253-4967.2015.01.019.
MA Yan, WU Ying, PANG Jian-zhang, et al. 2015. Theory and application of the stable cosmogenic nuclide ²¹Ne dating method［J］. Seismology and Geology, 37(1):242-255(in Chinese).
冉勇康, 邓起东. 1999. 古地震学研究的历史, 现状和发展趋势［J］. 科学通报, 44(1):12-20.
RAN Yong-kang, DENG Qi-dong. 1999. History, status and trend about the research of paleoseismology［J］. Chinese Science Bulletin, 44(10):880-889.
冉勇康, 李彦宝, 杜鹏, 等. 2014. 中国大陆古地震研究的关键技术与案例解析(3):正断层破裂特征、环境影响与古地震识别［J］. 地震地质, 36(2):287-301. doi:10.3969/j.issn.0253-4967.2014.02.001.
RAN Yong-kang, LI Yan-bao, DU Peng, et al. 2014. Key techniques and several case analysis in paleoseismic studies in mainland China(3):Rupture characteristics, environment impact and paleoseismic indicators on normal faults［J］. Seismology and Geology, 36(2):287-301(in Chinese).
冉勇康, 王虎, 李彦宝, 等. 2012. 中国大陆古地震研究的关键技术与案例解析(1):走滑活动断裂的探槽地点、布设与事件识别标志［J］. 地震地质, 34(2):197-210. doi:10.3969/j.issn.0253-4967.2012.02.001.
RAN Yong-kang, WANG Hu, LI Yan-bao, et al. 2012. Key techniques and several case analysis in paleoseismic studies in mainland China(1):Trenching sites, layouts and paleoseismic indicators on active strike-slip faults［J］. Seismology and Geology, 34(2):197-210(in Chinese).
冉勇康, 张培震, 胡博, 等. 2002. 大青山山前断裂呼和浩特段晚第四纪古地震活动历史［J］. 中国地震, 18(1):15-27.
RAN Yong-kang, ZHANG Pei-zhen, HU Bo, et al. 2002. Paleoseismic activity on the Hohhot segment of Daqingshan peidmont fault in the late Quaternary history［J］. Earthquake Research in China, 18(1):15-27(in Chinese).
闻学泽. 1995. 活动断裂地震潜势的定量评估［M］. 北京:地震出版社:1-150.
WEN Xue-ze. 1995. Quantitative Estimates of Seismic Potential on Active Faults［M］. Seismological Press, Beijing:1-150(in Chinese).
尹金辉, 杨雪, 郑勇刚. 2016. 基岩就地¹⁴C测年及古地震潜在应用［J］. 地震地质, 38(3):773-782. doi:10.3969/j.issn.0253-4967.2016.03.021.
YIN Jin-hui, YANG Xue, ZHENG Yong-gang. 2016. Review on in-situ cosmogenic ¹⁴C dating and potential application in paleoearthquake［J］. Seismology and Geology, 38(3):773-782(in Chinese).
张进江. 2007. 北喜马拉雅及藏南伸展构造综述［J］. 地质通报, 26(6):639-649.
ZHANG Jin-jiang. 2007. A review on the extensional structures in the northern Himalaya and southern Tibet［J］. Geological Bulletin of China, 26(6):639-649(in Chinese).
Akçar N, Tikhomirov D, Özkaymak Ç, et al. 2012. ³⁶Cl exposure dating of paleoearthquakes in the Eastern Mediterranean:First results from the western Anatolian Extensional Province, Manisa fault zone, Turkey［J］. Geological Society of America Bulletin, 124(11-12):1724-1735.
Armijo R, Lyon-Caen H, Papanastassiou D. 1991. A possible normal-fault rupture for the 464 BC Sparta earthquake［J］. Nature, 351(6322):137-139.
Armijo R, Lyoncaen H, Papanastassiou D. 1992. East-west extension and Holocene normal-fault scarps in the Hellenic arc［J］. Geology, 20(6):491.
Armijo R, Tapponnier P, Mercier J L, et al. 1986. Quaternary extension in southern Tibet:Field observations and tectonic implications［J］. Journal of Geophysical Research:Solid Earth, 91(B14):13803-13872.
Balco G, Stone J O. 2003. Measuring the density of rock, sand, till, etc. UW Cosmogenic Nuclide Laboratory, methods and procedures［EB/OL］. http://depts.washington.edu/cosmolab/chem.html.
Benavente C, Zerathe S, Audin L, et al. 2017. Active transpressional tectonics in the Andean forearc of southern Peru quantified by ¹⁰Be surface exposure dating of an active fault scarp［J］. Tectonics, 36(9):1662-1678.
Benedetti L, Finkel R, King G, et al. 2003. Motion on the Kaparelli Fault(Greece)prior to the 1981 earthquake sequence determined from ³⁶Cl cosmogenic dating［J］. Terra Nova, 15(2):118-124.
Benedetti L, Finkel R, Papanastassiou D, et al. 2002. Post-glacial slip history of the Sparta Fault(Greece)determined by ³⁶Cl cosmogenic dating:Evidence for non-periodic earthquakes［J］. Geophysical Research Letters, 29(8):87-1-87-4.
Benedetti L, Manighetti I, Gaudemer Y, et al. 2013. Earthquake synchrony and clustering on Fucino faults(central Italy)as revealed from in situ ³⁶Cl exposure dating［J］. Journal of Geophysical Research:Solid Earth, 118(9):4948-4974.
Benedetti L C, Van Der Woerd J. 2014. Cosmogenic nuclide dating of earthquakes, faults, and toppled blocks［J］. Elements, 10(5):357-361.
Berryman K, Cochran U, Clark K, et al. 2012. Major earthquakes occur regularly on an isolated plate boundary fault［J］. Science, 336:1690-1693.
Bubeck A, Wilkinson M, Roberts G P, et al. 2015. The tectonic geomorphology of bedrock scarps on active normal faults in the Italian Apennines mapped using combined ground penetrating radar and terrestrial laser scanning［J］. Geomorphology, 237:38-51.
Carcaillet J, Manighetti I, Chauvel C, et al. 2008. Identifying past earthquakes on an active normal fault(Magnola, Italy)from the chemical analysis of its exhumed carbonate fault plane［J］. Earth and Planetary Science Letters, 271(1):145-158.
Cowie P, Phillips R, Roberts G, et al. 2017. Orogen-scale uplift in the central Italian Apennines drives episodic behaviour of earthquake faults［J］. Scientific Reports, 7:44858.
Espanon V R, Honda M, Chivas A R. 2014. Cosmogenic ³He and ²¹Ne surface exposure dating of young basalts from Southern Mendoza, Argentina［J］. Quaternary Geochronology, 19:76-86.
Friedrich A M, Wernicke B P, Niemi N A, et al. 2003. Comparison of geodetic and geologic data from the Wasatch region, Utah, and implications for the spectral character of Earth deformation at periods of 10 to 10 million years［J］. Journal of Geophysical Research:Solid Earth, 108(B4), 2199. doi:10.1029/2001JB000682.
Giaccio B, Galadini F, Sposato A, et al. 2003. Image processing and roughness analysis of exposed bedrock fault planes as a tool for paleoseismological analysis:Results from the Campo Felice Fault(central Apennines, Italy)［J］. Geomorphology, 49(3-4):281-301.
Gosse J C, Phillips F M. 2001. Terrestrial in situ cosmogenic nuclides:Theory and application［J］. Quaternary Science Reviews, 20(14):1475-1560.
He H, Wei Z, Densmore A. 2016. Quantitative morphology of bedrock fault surfaces and identification of paleo-earthquakes［J］. Tectonophysics, 693:22-31.
Heineke C, Niedermann S, Hetzel R, et al. 2016. Surface exposure dating of Holocene basalt flows and cinder cones in the Kula volcanic field(western Turkey)using cosmogenic ³He and ¹⁰Be［J］. Quaternary Geochronology, 34:81-91.
Liu-Zeng J, Shao Y, Klinger Y, et al., 2015. Variability in magnitude of paleoearthquakes revealed by trenching and historical records, along the Haiyuan Fault, China［J］. Journal of Geophysical Research:Solid Earth, 120(12):8304-8333.
Kastelic V, Burrato P, Carafa M, et al. 2017. Repeated surveys reveal nontectonic exposure of supposedly active normal faults in the central Apennines, Italy［J］. Journal of Geophysical Research:Earth Surface, 122(1):114-129.
Kong P, Fink D, Na C, et al. 2010. Dip-slip rate determined by cosmogenic surface dating on a Holocene scarp of the Daju Fault, Yunnan, China［J］. Tectonophysics, 493(1-2):106-112.
Kumar S, Wesnousky S G, Rockwell T K, et al. 2006. Paleoseismic evidence of great surface rupture earthquakes along the Indian Himalaya［J］. Journal of Geophysical Research:Solid Earth, 111:B03304.
Manighetti I, Campillo M, Bouley S, et al. 2007. Earthquake scaling, fault segmentation, and structural maturity［J］. Earth Planetary Science Letters, 253:429-438.
Manighetti I, Boucher E, Chauvel C, et al. 2010. Rare earth elements record past earthquakes on exhumed limestone fault planes［J］. Terra Nova, 22(6):477-482.
Marchetti D W, Hynek S A, Cerling T E. 2014. Cosmogenic ³He exposure ages of basalt flows in the northwestern Payún Matru volcanic field, Mendoza Province, Argentina［J］. Quaternary Geochronology, 19:67-75.
McCalpin J P. 2009. Paleoseismology［M］. Second Edition. Oxford:Academic Press.
McCalpin J P, Nishenko S P. 1996. Holocene paleoseismicity, temporal clustering, and probabilities of future large(M>7)earthquakes on the Wasatch fault zone, Utah［J］. Journal of Geophysical Research:Solid Earth, 101(B3):6233-6253.
Mitchell S G, Matmon A, Bierman P R, et al. 2001. Displacement history of a limestone normal fault scarp, northern Israel, from cosmogenic ³⁶Cl［J］. Journal of Geophysical Research:Solid Earth, 106(B3):4247-4264.
Palumbo L, Benedetti L, Bourles D, et al. 2004. Slip history of the Magnola Fault(Apennines, central Italy)from ³⁶Cl surface exposure dating:Evidence for strong earthquakes over the Holocene［J］. Earth and Planetary Science Letters, 225(1-2):163-176.
Ran Y K, Chen L C, Chen J, et al. 2010. Paleoseismic evidence and repeat time of large earthquakes at three sites along the Longmenshan fault zone［J］. Tectonophysics, 491(1):141-153.
Rood D, Amidon W, McKeon R, et al. 2015. Paleoseismic assessment of the Hat Creek Fault using cosmogenic He-3 surface exposure dating in basalt, northeastern California:A proof of concept study［C］. AGU Fall Meeting Abstracts.
Saillard M, Petit C, Rolland Y, et al. 2014. Late Quaternary incision rates in the Vésubie catchment area(southern French Alps)from in situ-produced ³⁶Cl cosmogenic nuclide dating:Tectonic and climatic implications［J］. Journal of Geophysical Research:Earth Surface, 119(5):1121-1135.
Schimmelpfennig I, Benedetti L, Finkel R, et al. 2009. Sources of in-situ ³⁶Cl in basaltic rocks. Implications for calibration of production rates［J］. Quaternary Geochronology, 4(6):441-461.
Schimmelpfennig I, Benedetti L, Garreta V, et al. 2011a. Calibration of cosmogenic ³⁶Cl production rates from Ca and K spallation in lava flows from Mt. Etna(38°N, Italy)and Payun Matru(36°S, Argentina)［J］. Geochimica et Cosmochimica Acta, 75(10):2611-2632.
Schimmelpfennig I, Williams A, Pik R, et al. 2011b. Inter-comparison of cosmogenic in-situ³He, ²¹Ne and ³⁶Cl at low latitude along an altitude transect on the SE slope of Kilimanjaro volcano(3°S, Tanzania)［J］. Quaternary Geochronology, 6(5):425-436.
Schlagenhauf A, Gaudemer Y, Benedetti L, et al. 2010. Using in situ Chlorine-36 cosmonuclide to recover past earthquake histories on limestone normal fault scarps:A reappraisal of methodology and interpretations［J］. Geophysical Journal International, 182(1):36-72.
Schlagenhauf A, Manighetti I, Benedetti L, et al. 2011. Earthquake supercycles in central Italy, inferred from ³⁶Cl exposure dating［J］. Earth and Planetary Science Letters, 307(3):487-500.
Schwartz D P, Coppersmith K J. 1984. Fault behavior and characteristic earthquakes:Examples from the Wasatch and San Andreas fault zones［J］. Journal of Geophysical Research:Solid Earth, 89(B7):5681-5698.
Shao Y, Yuan D, Oskin M E, et al. 2017. Historical(Yuan Dynasty)earthquake on the North Danghe Nanshan thrust, western Qilian Shan, China［J］. Bulletin of the Seismological Society of America, 107(3):1175-1184.
Shen X, Li D, Tian Y, et al. 2016. Late Pleistocene-Holocene slip history of the Langshan-Seertengshan piedmont fault(Inner Mongolia, northern China)from cosmogenic¹⁰Be dating on a bedrock fault scarp［J］. Journal of Mountain Science, 13(5):882-890.
Sieh K E. 1978. Prehistoric large earthquakes produced by slip on the San Andreas Fault at Pallett Creek, California［J］. Journal of Geophysical Research:Solid Earth, 83(B8):3907-3939.
Stone J O, Allan G, Fifield L K, et al. 1996. Cosmogenic chlorine-36 from calcium spallation［J］. Geochimica et Cosmochimica Acta, 60(4):679-692.
Stone J O, Ballantyne C K, Fifield L K. 1998. Exposure dating and validation of periglacial weathering limits, northwest Scotland［J］. Geology, 26(7):587-590.
Swan F H, Schwartz D P, Cluff L S. 1980. Recurrence of moderate-to-large magnitude earthquakes produced by surface faulting on the Wasatch fault zone, Utah［J］. Bulletin of the Seismologlcal of Society of America, 70(5):1431-1462.
Taylor M, Yin A. 2009. Active structures of the Himalayan-Tibetan orogen and their relationships to earthquake distribution, contemporary strain field, and Cenozoic volcanism［J］. Geosphere, 5(3):199-214.
Tesson J, Pace B, Benedetti L, et al. 2016. Seismic slip history of the Pizzalto Fault(central Apennines, Italy)using in situ-produced ³⁶Cl cosmic ray exposure dating and rare earth element concentrations［J］. Journal of Geophysical Research:Solid Earth, 121(3):1983-2003.
Tikhomirov D, Akçar N, Ivy-Ochs S, et al. 2014. Calculation of shielding factors for production of cosmogenic nuclides in fault scarps［J］. Quaternary Geochronology, 19(2):181-193.
Weldon R J, Fumal K S, Biasi G. 2004. Wrightwood and the earthquake cycle:What a long recurrence record tells us about how faults work［J］. GSA Today, 14:4-10.
Zreda M, Noller J S. 1998. Ages of prehistoric earthquakes revealed by cosmogenic chlorine-36 in a bedrock fault scarp at Hebgen Lake［J］. Science, 282(5391):1097-1099.

[1]	吴中海, 白玛多吉, 叶强, 韩帅, 史亚然, 尼玛次仁, 高扬. 西藏阿里阿鲁错地堑系的第四纪活动性、最新同震地表破裂及其地震地质意义[J]. 地震地质, 2023, 45(1): 67-91.
[2]	李启雷, 李玉丽, 屠泓为, 刘文邦. 丁青地区地震重定位、震源机制及其发震构造初步分析[J]. 地震地质, 2021, 43(1): 209-231.
[3]	陈健龙, 张冬丽, 周宇. 利用Envisat ASAR数据探讨渭河盆地断层现今的滑动速率[J]. 地震地质, 2020, 42(2): 333-345.
[4]	罗全星, 李传友, 任光雪, 李新男, 马字发, 董金元. 阳高-天镇断裂晚第四纪活动特征及滑动速率[J]. 地震地质, 2020, 42(2): 399-413.
[5]	黄伟亮, 杨晓平, 李胜强, 杨海波. 天山内部走滑断裂晚第四纪活动特征研究——以开都河断裂为例[J]. 地震地质, 2018, 40(5): 1040-1058.
[6]	黄伟亮, 杨晓平, 李胜强, 杨海波. 焉耆盆地北缘断裂全新世滑动速率及地震危险性[J]. 地震地质, 2018, 40(1): 186-203.
[7]	陈干, 郑文俊, 王旭龙, 张培震, 熊建国, 俞晶星, 刘兴旺, 毕海芸, 刘金瑞, 艾明. 榆木山北缘断裂现今构造活动特征及其对青藏高原北东扩展的构造地貌响应[J]. 地震地质, 2017, 39(5): 871-888.
[8]	尹金辉, 杨雪, 郑勇刚. 基岩就地¹⁴C测年及古地震潜在应用[J]. 地震地质, 2016, 38(3): 773-782.
[9]	黄伟亮, 杨晓平, 李安, 张玲, 李胜强, 杨海波. 焉耆盆地北缘和静逆断裂-褶皱带中晚第四纪变形速率[J]. 地震地质, 2015, 37(3): 675-696.
[10]	李煜航, 王庆良, 崔笃信, 郝明, 王文萍, 秦姗兰. 利用GPS数据反演阿尔金断裂现今滑动速率[J]. 地震地质, 2015, 37(3): 869-879.
[11]	任治坤, 张竹琪, 陈涛, 王伟涛. 侧向侵蚀相关的走滑断裂滑动速率计算新方法[J]. 地震地质, 2014, 36(4): 1020-1028.
[12]	冉勇康, 李彦宝, 杜鹏, 陈立春, 王虎. 中国大陆古地震研究的关键技术与案例解析(3)——正断层破裂特征、环境影响与古地震识别[J]. 地震地质, 2014, 36(2): 287-301.
[13]	常祖峰, 杨盛用, 周青云, 张艳凤, 谢英情. 2012年6月24日宁蒗-盐源M_S5.7地震发震构造刍议[J]. 地震地质, 2013, 35(1): 37-49.
[14]	王林, 田勤俭, 李德文, 张效亮. 京西北蔚县-广灵半地堑盆地南缘断裂带的断层生长研究[J]. 地震地质, 2011, 33(4): 828-838.
[15]	袁兆德, 陈杰, 张会平. 宇宙成因核素埋藏年龄测定及其在地球科学中的应用[J]. 地震地质, 2011, 33(2): 480-489.