Abstract:Thixotropy in this article refers to the property exhibited by saturated sludges and clays when with particle sizes less than 0.005mm become liquid upon stir or shake during strong earthquakes. The soft-sediment flow deformation structures triggered by earthquakes include liquefied flow deformation and thixotropic flow deformation. The former refers to the liquefaction and flow deformation of sand layers(including fine carbonate sediments);the latter refers to the flow of saturated argillaceous sediments. Thixotropic structures such as mud,clay,siliceous mud,lime mud, etc. are widely distributed in the stratigraphic record,and they mostly form a composite deformation structure with the liquefied deformation structure of the sand layer. Usually the geologists pay more attention to the features of sand layers or misinterpret the thixotropic structures of argillaceous sediment as the liquefied flow structures of sand. Based on the distribution pattern of saturated argillaceous sediments in the stratum,this paper divides the thixotropic flow deformation into four categories: (1)upward,(2)downward,(3)simultaneous upward and downward, and (4) nearly horizontal flows. In this paper, characteristics of these thixotropic features and their forming processes were described and interpreted in combination with field phenomena. Finally,thixotropic flow deformation structures have been systematically summarized. We hope that the thixotropic features would draw attention from geologists engaged in researches on soft sedimentary deformation and palaeoearthquakes.
[1] 陈希哲. 2004. 土力学与地基基础. 北京: 清华大学出版社. [Chen X Z.2004. Soil Mechanics and Geotechnical Engineering. Beijing: Tsinghua University Press] [2] 胡圣飞,李慧,胡伟,陈祥星. 2012. 触变性研究进展及应用综述. 湖北工业大学学报, 27(2): 57-60. [Hu S F,Li H,Hu W,Chen X X.2012. Progress and Application of Thixotropy. Journal of Hubei University of Technology, 27(2): 57-60] [3] 刘宝珺. 1980. 沉积岩石学. 北京: 地质出版社. [Liu B J.1980. Sedimentary Petrology. Beijing: Geological Publishing House] [4] 刘娟娟,曾国红,孟令帅,贺武斌. 2016. 扰动对粉土触变强度恢复影响规律研究. 地下空间与工程学报, 12(5): 1294-1299. [Liu J J,Zeng G H,Meng L S,He W B.2016. Research on the Influence of Disturbance on the Recovery of Thixotropic Strength of Silt. Chinese Journal of Underground Space and Engineering, 12(5): 1294-1299] [5] 乔秀夫,宋天锐,高林志,李海兵,彭阳,张传恒,章雨旭. 2007. 地层中地震记录(古地震). 北京: 地质出版社,1-263. [Qiao X F,Song T R,Gao L Z,Li H B,Peng Y,Zhang C H,Zhang Y X.2007. Earthquake Records in the Strata(Paleoearthquake). Beijing: Geological Publishing House,1-263] [6] 乔秀夫,李海兵. 2009. 沉积物的地震及古地震效应. 古地理学报, 11(6): 593-610. [Qiao X F,Li H B.2009. Effect of earthquake and ancient earthquake on sediments. Journal of Palaeogeography(Chinese Edition), 11(6): 593-610] [7] 乔秀夫,郭宪璞,李海兵,苟宗海,苏德辰,唐哲民. 2012. 龙门山晚三叠世软沉积物变形与印支期构造运动. 地质学报,86(1),132-156. [Qiao X F,Guo X P,Li H B,Gou Z H,Su D C,Tang Z M.2012. Soft-sediment deformation in the Late Triassic and the Indosinian Tectonic Movement in Longmenshan. Acta Geologica Sinica, 86(1): 132-156] [8] 乔秀夫,王彦斌. 2014. 华北克拉通中元古界底界年龄与盆地性质讨论. 地质学报, 88(9): 1623-1637. [Qiao X F,Wang Y B.2014. Discussions on the Lower Boundary Age of the Mesoroterozoic and Basin Tectonic Evolution of the Mesoproterozoic in North China Craton. Acta Geologica Sinica, 88(9): 1623-1637] [9] 乔秀夫,姜枚,李海兵,郭宪璞,苏德辰,许乐红. 2016. 龙门山中、新生界软沉积物变形及构造演化. 地学前缘,23(6),80-106. [Qiao X F,Jiang M,Li H B,Guo X P,Su D C,Xu L H,2016.Soft-sediment deformation structures and their implications for tectonic evolution from Mesozoic to Cenozoic in the Longmen Shan. Earth Science Frontiers, 23(6): 80-106] [10] 乔秀夫,李海兵,苏德辰,何碧竹,田洪水,郭宪璞,宋天锐,吕洪波,高林志,贺静,袁效奇,周玮,张淼,孙爱萍,王安东. 2017. 软沉积物变形构造: 地震与古地震记录. 北京: 地质出版社,1-264. [Qiao X F,Li H B,Su D C,He B Z,Tian H S,Guo X P,Song T R,Lu H B,Gao L Z,He J,Yuan X Q,Zhou W,Zhang M,Sun A P.2017. Soft Sediment Deformation Structures-Records of Earthquake and Paleoearthquake. Beijing: Geological Publishing House,1-264] [11] 苏德辰,孙爱萍. 2011. 北京永定河谷中元古界雾迷山组软沉积物变形与古地震发生频率. 古地理学报, 13(6): 591-614. [Su D C,Sun A P.2011. Soft-sediment deformation structures and the occurrence frequency of palaeoearthquake in Mesoproterozoic Wumishan Formation. Journal of Palaeogeography(Chinese Edition), 13(6): 591-614] [12] 苏德辰,李春旺,孙爱萍,乔秀夫. 2017. 太行山北缘中元古界发现泥火山群. 中国地质, 44(2): 399-400. [Su D C,Li C W,Sun A P,Qiao X F.2017. Mesoproterozoic mud volcanoes discovered in North Taihang Mountain: Preliminary results. Geology in China, 44(2): 399-400] [13] 田洪水,张邦花,祝介旺,张增奇,李洪奎. 2011. 早寒武世初期沂沭断裂带地震效应. 古地理学报, 13(6): 645-656. [Tian H S,Zhang B H,Zhu J W,Zhang Z Q,Li H K.2011. Seismic effects from the Yishu Zone during the Initial Stage of the Early Cambrian. Journal of Palaeogeography(Chinese Edition), 13(6): 645-656] [14] 田洪水,王华林,祝介旺,杨传成,吕明英,张慎河. 2015a. 山东安丘地区软土震陷及地震产生的土层构造新启示. 岩土工程学报, 37(4): 734-740. [Tian H S,Wang H L,Zhu J W,Yang C C,Lü M Y,Zhang S H.2015a. New revelation from seismic subsidence of soft soils and earthquake-induced soil-layer deformation structures in Anqiu area,Shandong Province. China Journal of Geotechnical Engineering, 37(4): 734-740] [15] 田洪水,张爱社,张慎河,张邦花,祝介旺,吕明英. 2015b. 饱和灰泥模拟地震试验与液化变形. 北京: 地震出版社,1-78. [Tian H S,Zhang A S,Zhang S H,Zhang B H,Zhu J W,Lü M Y.2015b. Simulation earthquake tests and liquefied deformations of the saturated lime-mud. Beijing: Seismological Press,1-78] [16] 田洪水,吕明英,张邦花,桑忠喜. 2015c. 山东济南下寒武统朱砂洞组软沉积变形中燧石的Sm-Nd年龄测定及其意义. 古地理学报, 17(1): 45-50. [Tian H S,Zhang B H,Zhu J W,Sang Z X.2015c. The Sm-Nd age of chert in the earthquake-induced soft sediment deformation structure from the Lower Cambrian Zhushadong Formation and its significance,Jinan of Shandong Province. Journal of Palaeogeography(Chinese Edition), 17(1): 45-50] [17] 田洪水,Wagoner Loon A J,王华林,张慎河,祝介旺. 2016. 大盛群中的震积岩: 郯庐断裂带构造与地震活动新证据. 中国科学: 地球科学, 46(1): 79-96. [Tian H S,Wagoner Loon A J,Wang H L,Zhang S H,Zhu J W.2016. Seismites in the Dasheng Group: New evidences of strong tectonic and earthquake activities of the Tanlu Fault zone. Science China: Earth Science, 46(1): 79-96] [18] 田洪水,祝介旺,王华林,张增奇,张邦花,张慎河. 2017. 沂沭断裂带及其近区地震事件地层的时空分布及意义. 古地理学报, 19(3): 393-417. [Tian H S,Zhu J W,Wang H L,Zhang Z Q,Zhang B H,Zhang S H.2017. Spatio-temporal distribution and significance of seismic event horizons in the Yishu Fault Zone and its adjacent area. Journal of Palaeogeography(Chinese Edition), 19(3): 393-417] [19] 田洪水,王华林,祝介旺,张慎河. 2018. 胶州上白垩统史家屯段中地震产生的震火山岩及软沉积物触变变形. 地震地质, 40(2): 1-16. [Tian H S,Wang H L,Zhu J W,Zhang S H.2018. Earthquake caused seimic volcanic rocks and thixotropic deformations of soft sediments in the Upper Cretaceous Shijiatun Member,Jiao Zhou City. Seismology and Geology, 40(2): 1-16] [20] 许志琴,王宗秀,候立玮. 1991. 松潘—甘孜造山带构造研究新进展. 中国地质,18(12): 14-16. [Xu Z Q,Wang Z X,Hou L W.1991. Recent Advances in Structural Research of Songpan-Ganzi Orogenic Belt. Chinese Geology,18(12): 14-16] [21] 张先伟,孔令伟,李峻,杨爱武. 2014. 黏土触变过程中强度恢复的微观机理. 岩土工程学报, 36(8): 1407-1413. [Zhang X W,Kong L W,Li J,Yang A W.2014. Microscopic mechanism of strength recovery in clay thixotropic process. Chinese Journal of Geotechnical Engineering, 36(8): 1407-1413] [22] 赵澄林,李儒峰,周劲松. 1997. 华北中新元古界油气地质与沉积学. 北京: 地质出版社. [Zhao C L,Li R F,Zhou J S.1997. Petroleum Geology and Sedimentology of Proterozoic in the Neogene,North China. Beijing: Geological Publishing House] [23] 郑勇,李海兵,王焕,张蕾,李成龙. 2018. 印支期龙门山断裂带的逆冲-推覆构造和沉积响应. 地质论评, 64(1): 45-61. [Zheng Y,Li H B,Wang H,Zhang L,Li C L.2018. Indosinian Thrust-Nappe Structure and Its Sedimentary Response in the Longmen Mts. Thrust Belt. Geological Review, 64(1): 45-61] [24] Bowman D,Korjenkov A,Porat N.2004. Late-Pleistocene seismites from Lake Issyk-Kul,the Tien Shan range,Kyrghyzstan. Sedimentary Geology, 163(3): 211-228. [25] Basilone L.2017. Seismogenic rotational slumps and translational glides in pelagic deep-water carbonates. Upper Tithonian-Berriasian of Southern Tethyan margin(W Sicily,Italy). Sedimentary Geology, 356: 1-14. [26] Garcia-Tortosa F J,Alfaro P,Gibert L,Scott G.2011. Seismically induced slump on an extremely gentle slope(<1°)of the Pleistocene Tecopa paleolake(California). Geology, 39(11): 1055-1058. [27] He B Z,Qiao X F.2015. Advances and overview of the study on paleo-earthquake events: A review of seismites. Acta Geologica Sinica-English Edition, 89(5): 1702-1746. [28] Liang L J,Dai F C,Jiang H C,Zhong N.2018. A preliminary study on the soft-sediment deformation structures in the late Quaternary lacustrine sediments at Tashkorgan,northeastern Pamir,China. Acta Geologica Sinica,In press. [29] Montenat C,Barrier P,Ott d'Estevou P, Hibsch C.2007. Seismites: An attempt at critical analysis and classification. Sedimentary Geology, 196(1): 5-30. [30] Rossetti D F,Bezerra F H R,Góes A M,Neves B B B.2011. Sediment deformation in Miocene and post-Miocene strata,Northeastern Brazil: Evidence for paleoseismicity in a passive margin. Sedimentary Geology, 235(3): 172-187. [31] Su D C,Qiao X F,Sun A P,Li H B,Somerville I D.2014. Large earthquake-triggered liquefaction mounds and a carbonate sand volcano in the Mesoproterozoic Wumishan Formation,Beijing,North China. Geological Journal, 49(1): 69-89. [32] Su D C,Sun A P.2012. Typical earthquake-induced soft-sediment deformation structures in the Mesoproterozoic Wumishan Formation,Yongding River Valley,Beijing,China and interpreted earthquake frequency. Journal of Palaeogeography, 1(1): 71-89. [33] Tian H S,Zhang Z Q,Zhang B H,Zhu J W,Sang Z X.2013. Tectonic taphrogenesis and paleoseismic records from the Yishu fault zone in the initial stage of the Caledonian Movement Acta Geologica Sinica-English Edition, 87(4): 936-947. [34] Tian H S,Zhang S H,Zhang A S.2016. Test investigation on liquefied deformation structure in saturated lime-mud composites triggered by strong earthquakes. Acta Geologica Sinica-English Edition, 90(6): 2008-2021. [35] Zhai M G.2015. The research directions and ideas of material evolution of continental dynamics. Journal of Earth Sciences & Environment,37(4): 1-14.