RESEARCH ON TECTONIC STRESS OF THE NORTHEAST SEGMENT OF HANCHENG FAULT ZONE

doi:10.3969/j.issn.0253-4967.2015.02.010

Abstract

Abstract:

Knowledge about regional stress field is a significant basis for better understanding the tectonic activity of faults. This study reports the magnetic fabric investigation performed at sites along the northeastern section of the Hancheng Fault zone after we finished the 1 : 50,000 field mapping of active fualts in this region. Samples were collected at selected sites at Shaojialing, Zhubeizhuang and Shangyukou. Our results show that magnetic fabric, derived from anisotropy of magnetic susceptibility, reveals oblate susceptibility ellipsoids that are slightly modified compared to the inferred original depositional fabric. A dominant distribution of K_max along the NW-SE direction indicates that the northeastern section of the Hancheng Fault zone is subjected to horizontal extensional stress along this direction. A weakly NW-SE directional distribution of K_min is interpreted to reflect the action of horizontal compressive stress. This NW-SE compressive stress at the Shaojialing site appears to be somewhat stronger than that at the Shangyukou and Zhubeizhuang sites. Nevertheless, magnetic fabric properties are located in the oblate area in the P_J-T and Flinn diagrams. This may reflect inhomogeneous distributions of tectonic stresses along the Hancheng Fault zone, indicating that even within a strongly extensional stress-field, prolate magnetic fabric may be difficult to develop. This work may provide basic evidence for further studies on the activity of the Hancheng Fault zone.

Key words: Hancheng Fault, magnetic fabric, tectonic stress, magnetic minerals

摘要：

断裂带的区域构造应力特征是研究其活动性的重要依据。在应变指示计较少的弱应变地区, 磁组构是有效可选的手段。在韩城断裂带1/5 万活动断层填图工作的基础上, 对断裂带NE段的上峪口、渚北庄与邵家岭剖面进行了系统的岩石磁组构研究。结果表明, 该区域三叠纪岩石样品磁化率椭球体以"扁球型"为主, 表现出弱变形组构的典型特征。磁化率椭球体最大轴K_max沿NW-SE向与最小轴K_min沿NE-SW向的分布趋势, 以及断层两盘明显的差异性垂直运动、断层划痕与河流扭曲等野外证据, 反映出韩城断裂带NE段受控于NW-SE向的拉张应力, 兼有相对较弱的NE-SW向的水平挤压应力作用。断裂带不同地方的应力状态也存在一定的差异, 研究区的上峪口与渚北庄剖面受到的水平挤压应力相对较弱; 邵家岭则表现出较强的挤压应力作用。但邵家岭剖面大多数样品仍然落于"扁球型"区域内, 可能说明在拉张应力控制的构造单元, 即使挤压应力较为明显, 沉积岩中的"拉长型"磁组构仍难以形成。

关键词: 韩城断裂, 磁组构, 构造应力, 磁性矿物

CLC Number:

P315.2

LI Zi-hong, LI Bin, LIU Hong-fu, YAN Xiao-bing, HU Gui-rang. RESEARCH ON TECTONIC STRESS OF THE NORTHEAST SEGMENT OF HANCHENG FAULT ZONE[J]. SEISMOLOGY AND GEOLOGY, 2015, 37(2): 468-481.

李自红, 李斌, 刘鸿福, 闫小兵, 扈桂让. 韩城断裂带NE段构造应力特征[J]. 地震地质, 2015, 37(2): 468-481.

References

崔可锐, 施央申. 1998. 岩石磁组构在构造混杂岩带和韧性剪切带研究中的应用: 以西天山地区为例【J】. 地球物理学进展, 13(1): 40—51.
CUI Ke-rui, SHI Yang-shen. 1998. The apply of rock magnetic fabric in melange zone and ductile shear zone, exemplified by the west Tianshan area 【J】. Progress in Geophysics, 13(1): 40—51(in Chinese).
邓起东, 王克鲁, 汪一鹏, 等. 1973. 山西隆起区断陷地震带地震地质条件及地震发展趋势概述【J】. 地质科学, (1): 37—47.
DENG Qi-dong, WANG Ke-lu, WANG Yi-peng, et al. 1973. On the tendency of seismicity and their geological set up of the seismic belt of Shanxi Graben 【J】. Scientia Geologica Sinica, (1): 37—47(in Chinese).
李斌, Reidar Lovlie, 苏朴, 等. 2008. 山西襄汾大柴更新统剖面划分的新观点【J】. 地球物理学报, 51(4): 1040—1047.
LI Bin, Reidar Lovlie, SU Pu, et al. 2008. A new stratification of the Dachai Pleistocene section, Xiangfen, Shanxi, China 【J】. Chinese Journal of Geophysics, 51(4): 1040—1047(in Chinese).
李建忠, 潘忠习, 冯心涛, 等. 2006. 聂拉木地区高喜马拉雅岩石磁组构及其构造含义【J】. 地球物理学报, 49(2): 496—503.
LI Jian-zhong, PAN Zhong-xi, FENG Xin-tao, et al. 2006. Magnetic fabrics and tectonic implications of the Higher Himalayan rocks in Nyalam, southern Tibet 【J】. Chinese Journal of Geophysics, 49(2): 496—503(in Chinese).
李震宇, 黄宝春, 张春霞. 2010. 河南西南部典型白垩纪剖面的岩石磁组构特征及其构造意义【J】. 岩石学报, 26(11): 3418—3430.
LI Zhen-yu, HUANG Bao-chun, ZHANG Chun-xia. 2010. Characteristic of anisotropy of magnetic susceptibility(AMS)and its tectonic significance in typical Cretaceous section from Xixia Basin, Central China 【J】. Acta Petrologica Sinica, 26(11): 3418—3430(in Chinese).
梁文天, 张国伟, 鲁如魁, 等. 2009. 秦祁接合带造山缝合带磁组构特征及其构造意义【J】. 地球物理学报, 52(1): 140—149.
LIANG Wen-tian, ZHANG Guo-wei, LU Ru-kui, et al. 2009. Magnetic fabric study and its tectonic significance of suture zones in joint area of Qinling and Qilianshan 【J】. Chinese Journal of Geophysics, 52(1): 140—149(in Chinese).
潘永信, 朱日祥. 1998. 磁组构研究现状【J】. 地球物理学进展, 13(1): 52—59.
PAN Yong-xin, ZHU Ri-xiang. 1998. The recent progress in the magnetic fabrics 【J】. Progress in Geophysics, 13(1): 52—59(in Chinese).
申屠炳明, 徐煜坚, 汪一鹏. 1990. 韩城断裂的活动特征及断裂带古地震遗迹的初步研究【J】. 华北地震科学, 8(1): 1—10.
SHENTU Bing-ming, XU Yu-jian, WANG Yi-peng. 1990. Preliminary study of the characteristics of the activity of Hancheng Fault and earthquake vestiges near the fault 【J】. North China Earthquake Sciences, 8(1): 1—10(in Chinese).
沈忠悦, 方大钧, 叶瑛, 等. 1999. 江山-绍兴碰撞带的磁组构特征及其构造地质意义【J】. 科学通报, 44(10): 1093.
SHEN Zhong-yue, FANG DA-jun, YE Ying, et al. 1999. Magnetic fabrics in the Jiangshan-Shaoxing collisional zone and their tectonic implication 【J】. Chinese Science Bulletin, 44(10): 1093(in Chinese).
王喜生, Lovlie Reidar, 苏朴. 2002. 许家窑泥河湾沉积物的岩石磁学性质【J】. 中国科学(D辑), 32(4): 271—278.
WANG Xi-sheng, Lovlie Reidar, SU Pu. 2002. Rock magnetic properties of Nihewan sediments at Xujiayao 【J】. Science in China(Ser D), 32(4): 271—278(in Chinese).
徐柏安. 1990. 岩石的磁各向异性及其在地质上的应用【J】. 地质与勘探, 26(6): 39—46.
XU Bai-an. 1990. Anisotropy of magnetic susceptibility of rocks and its application to geology 【J】. Geology and Exploration, 26(6): 39—46(in Chinese).
许顺山, 陈柏林. 1998. 应用岩石磁性组构研究动力变形作用【J】. 地球学报, 19(1): 19—24.
XU Shun-shan, CHEN Bai-lin. 1998. Studying on dynamic deformation by magnetic fabric 【J】. Acta Geoscientia Sinica, 19(1): 19—24(in Chinese).
阎凤忠, 贺勇, 安卫平, 等. 1987. 韩城-侯马断陷区主要活动断裂的调查【J】. 山西地震, (3): 9—13.
YAN Feng-zhong, HE Yong, AN Wei-ping, et al. 1987. The investigation of main active faults in the Hancheng-Houma faulted depression 【J】. Earthquake Research in Shanxi, (3): 9—13(in Chinese).
杨坤光, 刘强, 刘育燕, 等. 2003. 大别山双河同构造花岗岩体显微构造与磁组构研究【J】. 中国科学(D辑), 33(11): 1050—1056.
YANG Kun-guang, LIU Qiang, LIU Yu-yan, et al. 2003. A study of microstructure and magnetic fabrics of Shuanghe syntectonic granite in the Dabie Mountains 【J】. Science in China(Ser D), 33(11): 1050—1056(in Chinese).
杨梅忠, 阎嘉祺. 1994. 陕西韩城北山山地破裂带特征及成因研究【J】. 西北地震学报, 16(1): 90—92.
YANG Mei-zhong, YAN Jia-qi. 1994. Study on features of mountain rupture zones and its causes of Beishan Mt. of Hancheng, Shaanxi 【J】. Northwestern Seismological Journal, 16(1): 90—92(in Chinese).
张安良, 米丰收. 1987. 陕西韩城龙湾-上峪口现今破裂带成因探讨【J】. 地震地质, 9(4): 55—61.
ZHANG An-liang, MI Feng-shou. 1987. Discussion on genesis of recent Longwan-Shangyukou fracture zone in Hancheng County, Shaanxi Province 【J】. Seismology and Geology, 9(4): 55—61(in Chinese).
周勇, 王二七, 李齐, 等. 2001. 拉脊山及邻区磁组构特征及其地质意义【J】. 中国科学(D辑), 31(B12): 187—194.
ZHOU Yong, WANG Er-qi, LI Qi, et al. 2001. Characteristic of magnetic susceptibility anisotropy in and around Laji Shan and its geological significance 【J】. Science in China(Ser D), 31(B12): 187—194(in Chinese).
周勇, 许荣华, 阎月华, 等. 2000. 喀喇昆仑断裂带磁组构特征及其构造意义【J】. 岩石学报, 16(1): 134—144.
ZHOU Yong, XU Rong-hua, YAN Yue-hua, et al. 2000. Characteristics of magnetic fabrics of the Karakoram Fault belt and its tectonic significance 【J】. Acta Petrologica Sinica, 16(1): 134—144(in Chinese).
Aubourg C, Rochette P, Vialon P. 1991. Subtle stretching lineation revealed by magnetic fabric of Callovian-Oxfordian black shales(French Alps)【J】. Tectonophysics, 185(3): 211—223.
Borradaile G J. 1988. Magnetic susceptibility, petrofabrics and strain 【J】. Tectonophysics, 156(1): 1—20.
Cifelli F, Rossetti F, Mattei M, et al. 2004. An AMS, structural and paleomagnetic study of Quaternary deformation in eastern Sicily 【J】. Journal of Structural Geology, 26(1): 29—46.
Hrouda F, Krej A?í O, Potfaj M, et al. 2009. Magnetic fabric and weak deformation in sandstones of accretionary prisms of the Flysch and Klippen Belts of the Western Carpathians: Mostly offscraping indicated 【J】. Tectonophysics, 479(3): 254—270.
Jelinek V. 1981. Characterization of magnetic fabric of rocks 【J】. Tectonophysics,79: 63—67.
Kissel C, Barrier E, Laj C, et al. 1986. Magnetic fabric in "undeformed" marine clays from compressional zones 【J】. Tectonics, 5(5): 769—781.
Lowrie W, Hirt A M. 1987. Anisotropy of magnetic susceptibility in the Scaglia Rossa pelagic limestone 【J】. Earth and Planetary Science Letters, 82(3): 349—356.
Mattei M, Speranza F, Argentieri A, et al. 1999. Extensional tectonics in the Amantea Basin(Calabria, Italy): A comparison between structural and magnetic anisotropy data 【J】. Tectonophysics, 307(1): 33—49.
Moskowitz B M, Hargraves. 1984. Magnetic cristobalite(?): A possible new magnetic phase produced by the thermal decomposition of nontronite 【J】. Science, 225(4667): 1152—1154.
Nagata T. 1961. Rock Magnetism 【M】. Tokyo: Maruzen Company. 5—23.
Parés J M. 2004. How deformed are weakly deformed mudrocks?Insights from magnetic anisotropy 【J】. Geological Society, London, Special Publications, 238(1): 191—203.
Parés J M, van der Pluijm B A. 2002. Evaluating magnetic lineations(AMS)in deformed rocks 【J】. Tectonophysics, 350(4): 283—298.
Parés J M, van der Pluijm B A, Dinarès-Turell J. 1999. Evolution of magnetic fabrics during incipient deformation of mudrocks(Pyrenees, northern Spain)【J】. Tectonophysics, 307(1): 1—14.
Rochette P, Jackson M, Aubourg C. 1992. Rock magnetism and the interpretation of anisotropy of magnetic susceptibility 【J】. Reviews of Geophysics, 30(3): 209—226.
Sagnotti L, Speranza F, Winkler A, et al. 1998. Magnetic fabric of clay sediments from the external northern Apennines(Italy)【J】. Physics of the Earth and Planetary Interiors, 105(1): 73—93.
Sagnotti L, Faccenna C, Funiciello R, et al. 1994. Magnetic fabric and structural setting of Plio-Pleistocene clayey units in an extensional regime: The Tyrrhenian margin of central Italy 【J】. Journal of Structural Geology, 16(9): 1243—1257.
Tarling D, Hrouda F. 1993. Magnetic Anisotropy of Rocks 【M】. London: Springer. 1—189.

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