青藏高原东缘活动断裂带地壳岩体构造损伤特征与模式讨论
山地灾害与地表过程重点实验室，中国科学院、水利部成都山地灾害与环境研究所，成都 610041，中国
中国科学院大学，北京 100049，中国
中国科学院青藏高原地球科学卓越创新中心，北京 100101，中国
地质灾害防治与地质环境保护国家重点实验室(成都理工大学)，成都 610059，中国
中国科学院前沿科学重点研究项目(资助号：QYZDY-SSW-DQC006)，第2次青藏高原综合科学考察研究(资助号：2019QZKK0906)，国家自然科学基金(资助号：41941017，41520104002)
中图分类号:P642
Key Laboratory of Mountain Hazards and Surface Process, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
University of Chinese Academy of Sciences, Beijing 100049, China
CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China
活动断裂带强烈复杂的构造运动会对地壳岩体产生不同程度的损伤，这些损伤能够显著影响地震破裂、地貌演化和地质灾害等地质过程，并对工程岩体稳定有较大影响，但目前鲜见对大型活动断裂地壳岩体构造损伤的深入研究。本文首次提出地壳岩体构造损伤的科学概念，揭示其具有不可逆性、累积性、非均匀性与愈合性。通过对青藏高原东缘鲜水河断裂带等6条主要活动断裂带大范围岩体露头的实测分析，采用构造结构面面密度作为表征构造损伤的定量指标，将断裂带地壳岩体划分为损伤带与围岩，测得最宽损伤带达3100 m。分析了地壳岩体损伤分布特征、变形破裂特征和损伤分布影响因素，取得如下认识：(1)损伤带主要沿活动性较强的主断裂分布，其内部具有高、低损伤区交替的分区损伤特征；(2)损伤带与围岩岩体分别表现为高应变速率与低应变速率状态下脆性损伤特征，损伤带的形成与断裂近期区域应力场密切相关；(3)表征断层发展阶段的累积位移量控制损伤带的总体规模，而其局部变化主要受控于断裂的几何展布与岩石性质；(4)提出了典型活动断裂带地壳岩体构造损伤模式。研究成果可为地震动力学、构造地貌、地质灾害和大型工程建设等提供约束地壳岩体结构的科学证据，有助于深化对活动断裂带地壳岩体力学环境的认识和理解。
The strong and complex movement of active fault zones inevitably causes different degrees of damage to the crustal rock mass. These damages can significantly affect the processes of earthquake rupture, geomorphic evolution, geological disaster, and engineering rock mass. However, the tectonic damage of crustal rock mass around large active faults is still not well understood. The concept of the tectonic damage of crustal rock mass is firstly proposed. The tectonic damage is irreversible, accumulative, heterogeneous, and healable. We measure tectonic discontinuities of the outcrops in the six major fault zones on the eastern margin of the Tibetan Plateau. They are the Xianshuihe fault zone, the Longmenshan fault zone, the Anninghe fault zone, the Daliangshan fault zone, the Zemuhe fault zone, and the Xiaojiang fault zone. The crustal rock mass outside fault core can be divided into a damage zone and wall rock according to the intensity of tectonic discontinuities. This intensity is a quantitative index of tectonic damage. Then we analyze the spatial pattern, the characteristics of damage, and the influence factors of the tectonic damage of crustal rock mass. The main conclusions are as follows: (1)Damage degree shows a decrease with perpendicular distance from the main fault trace. High damage areas alternate with low damage areas in the damage zone. The widest damage zone is 3100 m; (2)The rock mass in damage zone and wall rock is damaged in brittle regime at high strain rate and low strain rate, respectively. And the orientations of tectonic discontinuities in damage zone show a strong correlation with recent crustal stress field; (4)The cumulative displacement that characterizes the development stage of faults determines the scale of the damage zone, and the local variations are mainly controlled by fault geometry and lithology; (5)A new conceptual model based on cumulative displacement, fault geometry, lithology, and depth is proposed to explain the pattern of the tectonic damage of crustal rock mass around the active fault zone. This study can provide evidences for constraining the structure of crustal rock masses in seismic dynamics, tectonic geomorphology, geological disaster, and engineering, and help to deepen the understanding of the crustal rock mass of active fault zones.
图 8测量点岩体构造结构面平均迹长(a)、面密度(c)与距主断裂距离关系；断层损伤带宽度d与断层累积位移量w的对数相关性(b)
Figure 8.The relationship between mean trace length(a) and area density(c) of tectonic discontinuity and the distance to the main fault trace of measuring outcrops; Logarithmic graphs showing relationships between cumulative displacement and the width of fault damage zone(b)
The relationship between mean trace length(a) and area density(c) of tectonic discontinuity and the distance to the main fault trace of measuring outcrops; Logarithmic graphs showing relationships between cumulative displacement and the width of fault damage zone(b)
图 9典型断层损伤带与围岩露头尺度及微观尺度岩体变形破裂特征
典型断层损伤带与围岩露头尺度及微观尺度岩体变形破裂特征
Figure 9.Typical outcrops and photomicrographs in the damage zone and wall rock showing the deformation features of rock mass at mesoscale and microscale
Typical outcrops and photomicrographs in the damage zone and wall rock showing the deformation features of rock mass at mesoscale and microscale
图 10鲜水河断裂带(a~d)、安宁河断裂带(e~h)与小江断裂带(i~l)断层损伤带与围岩的构造结构面产状(红色线段为主断层走向线，灰色箭头为主应力方向，σ损为损伤带主应力，σ围为围岩主应力)
鲜水河断裂带(a~d)、安宁河断裂带(e~h)与小江断裂带(i~l)断层损伤带与围岩的构造结构面产状(红色线段为主断层走向线，灰色箭头为主应力方向，σ损为损伤带主应力，σ围为围岩主应力)
Figure 10.Orientations of tectonic discontinuities in the damage zone and wall rock of the Xianshuihe fault zone(a~d), the Anninghe fault zone(e~h), (i~l) Xiaojiang fault zone(The red line is mean strike of the main fault, the grey arrow is the orientation of principal stress)
Orientations of tectonic discontinuities in the damage zone and wall rock of the Xianshuihe fault zone(a~d), the Anninghe fault zone(e~h), (i~l) Xiaojiang fault zone(The red line is mean strike of the main fault, the grey arrow is the orientation of principal stress)
图 11典型活动断裂带地壳岩体构造损伤模式(箭头为主应力方向，σ损为损伤带主应力，σ围为围岩主应力)
典型活动断裂带地壳岩体构造损伤模式(箭头为主应力方向，σ损为损伤带主应力，σ围为围岩主应力)
Figure 11.3D Model of crustal rock mass around active fault(The arrow is the orientation of principal stress)
3D Model of crustal rock mass around active fault(The arrow is the orientation of principal stress)
表 1各断裂带基本特征
各断裂带基本特征
Table 1.Basic information of the six study fault zones
Basic information of the six study fault zones
表 2各断裂带断层损伤带宽度
各断裂带断层损伤带宽度
Table 2.Width of damage zone of the six study fault zones
Width of damage zone of the six study fault zones
表 3各断裂带断层损伤带与围岩的构造结构面面密度与平均迹长
各断裂带断层损伤带与围岩的构造结构面面密度与平均迹长
Table 3.Area density and mean trace length of tectonic discontinuity in the damage zone and wall rock of the six study fault zones
Area density and mean trace length of tectonic discontinuity in the damage zone and wall rock of the six study fault zones
表 4典型活动断裂带地壳岩体构造结构面组合与主应力方向
典型活动断裂带地壳岩体构造结构面组合与主应力方向
Table 4.Orientations of tectonic discontinuities and principal stress in the damage zone and wall rock
Orientations of tectonic discontinuities and principal stress in the damage zone and wall rock
An Y F. 2010. Boundary features of the seismic rupture segments along the Xianshuihe fault zone[D]. Beijing: Institute of Geology, China Earthquake Administration.
He H L, Ikeda Y. 2007. Faulting on the anninghe fault zone, Southwest China in late quaternary ant its movement model[J]. Acta Seismologica Sinica, 29 (5): 537-548.
Hou G T, Pan W Q. 2013. The geological modeling and mechanical mechanism of fractures[M]. Beijing: Science Press.
Huang R Q, Xu M, Chen J P, et al. 2004. Fine description of complex rock mass structure and its engineering application[M]. Beijing: Science Press.
Li T T, Du Q F, You Z L, et al. 1998. The Xianshuihe active fault zone and assessment of strong earthquake[M]. Chengdu: Chengdu Map Press.
Li Y S, Shang Y Q, Wang S T. 1990. Activity of faults and occurrence conditions of earthquakes in Anning River development zone[J]. Geological Hazards and Environment Preservation, 1 (1): 10-18.
Liang M J. 2019. Characteristics of the Late-Quaternary fault activity of the Xianshuihe fault[D]. Beijing: Institute of Geology, China Earthquake Administration.
Peng J B, Cui P, Zhuang J Q. 2019. Challenges to engineering geology of Sichuan-Tibet railway[J]. Chinese Journal of Rock Mechanics and Engineering, 39 (12): 2377-2389.
Scholz C H. 2018. The mechanics of earthquakes and faulting[M]. 3rd edition. Cambridge: Cambridge University Press.
Smith Z, Griffith W A, Marren T, et al. 2019. Damage fabrics in crystalline vs. granular rocks formed in response to isotropic tension: Implications for coseismic off-fault pulverization[C]//AGU Fall Meeting Abstract. Washington. DC: American Geophysical Union: #MR23G-0179 2019.
Song F M, Wang Y P, Yu W X, et al. 1998. Xiaojiang active fault[M]. Beijing: Seismological Press.
Wang E, Burchfiel B C, Royden L H, et al. 1998. Late Cenozoic Xianshuihe-Xiaojiang, Red River, and Dali fault systems of southwestern Sichuan and central Yunnan, China[M]. Boulder, Colo. : Geological Society of America.
Wang X M, Zhang C G, Pei X Y, et al. 2013. Geological map of Anninghe active fault(Xining-Tuowu segment)[M]. Beijing: Seismological Press.
Wang Y P, Song F M, Cao Z Q, et al. 2012. Geological map of Xiaojiang active fault[M]. Beijing: Seismological Press.
Xu X W, Han Z J, Yang X P, et al. 2016. Seismotectonic map in China and its adjacent regions[M]. Beijing: Seismological Press.
Yang S Q. 2002. Study on theory and application of blasting vibration cumulative effects[D]. Changsha: Central South University.
Zemuhe Active Fault Mapping Team, Seismic Crew for Seismology and Geology, Sichuan Provincial Seismological Bureau. 2013. Geological map of Zemuhe active fault[M]. Beijing: Seismological Press.
Zhao X Y, Li K P, Xiao D, et al. 2020. Slaking characteristics of silty mudstone under acid rain action based on fractal dimension[J]. Journal of Engineering Geology, 28 (2): 232-239.
安艳芬. 2010. 鲜水河断裂带地震破裂段落的边界特征研究[D]. 北京: 中国地震局地质研究所.
侯贵廷, 潘文庆. 2013. 裂缝地质建模及力学机制[M]. 北京: 科学出版社.
黄润秋, 许模, 陈剑平, 等. 2004. 复杂岩体结构精细描述及其工程应用[M]. 北京: 科学出版社.
李天祒, 杜其方, 游泽李, 等. 1998. 鲜水河活动断裂带及强震危险性评估[M]. 成都: 成都地图出版社.
梁明剑. 2019. 鲜水河断裂晚第四纪活动习性[D]. 北京: 中国地震局地质研究所.
四川省地震局地震地质队则木河活动断裂带填图组. 2013. 则木河活动断裂带地质图[M]. 北京: 地震出版社.
宋方敏, 汪一鹏, 俞维贤, 等. 1998. 小江活动断裂带[M]. 北京: 地震出版社.
汪一鹏, 宋方敏, 曹忠权, 等. 2012. 小江活动断裂地质图[M]. 北京: 地震出版社.
王新民, 张成贵, 裴锡瑜, 等. 2013. 安宁河活动断裂带(西宁-拖乌段)地质图[M]. 北京: 地震出版社.
徐锡伟, 韩竹军, 杨晓平, 等. 2016. 中国及邻近地区地震构造图[M]. 北京: 地震出版社.
阳生权. 2002. 爆破地震累积效应理论和应用初步研究[D]. 长沙: 中南大学.
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The relationship between mean trace length(a) and area density(c) of tectonic discontinuity and the distance to the main fault trace of measuring outcrops; Logarithmic graphs showing relationships between cumulative displacement and the width of fault damage zone(b)
Typical outcrops and photomicrographs in the damage zone and wall rock showing the deformation features of rock mass at mesoscale and microscale
Orientations of tectonic discontinuities in the damage zone and wall rock of the Xianshuihe fault zone(a~d), the Anninghe fault zone(e~h), (i~l) Xiaojiang fault zone(The red line is mean strike of the main fault, the grey arrow is the orientation of principal stress)
3D Model of crustal rock mass around active fault(The arrow is the orientation of principal stress)
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