天山造山带地壳结构与构造──乌鲁木齐─库尔勒地震转换波测深剖面
|
摘要
沿乌鲁木齐－库尔勒３５０余公里长的测线上完成了穿越天山的地震转换波野外观测，得出天山造山带的深部构造剖面图和壳内Ｐ，Ｓ波速度结构模型．天山的结晶地壳可分为４层，各层的速度分别是：Ｖｐ值为５．９，６．３，６．６，６．９ｋｍ／ｓ；Ｖｓ值为３．２，３．５，３．７，３．９ｋｍ／ｓ。上地幔顶部的波速：Ｖｐ值为８．１０ｋｍ／ｓ。Ｖｓ值为４．６ｋｍ／ｓ。天山地区的地壳厚度为４２－５６ｋｍ，中天山最厚，达到５０－５６ｋｍ。地壳中部存在低速透镜体。探测结果表明，天山大地构造可分为北天山、中天山和南天山３个区，其地壳深部构造特征各不相同。用颤动构造理论来解释天山造山带的形成机制和演化较板块构造理论更为合理。
A deep-sounding observations by using the PS converted waves of the earthquakes along the rmqi-Korla profile across the Tianshan mountains have been conducted with the cooperation efforts of Chinese, Kazakhstan and Kirghizstan scientists in 1992. As a results a cross-ection of deep crust structures and the velocity models of P and S waves along the profile were obtained. The consolidate crust of the Tianshan mountains is consisted of 4 layers with the velocities of Vp=5.9km/s, 6.3km/s, 6.6km/s, 6.9km/s, Vs=3.2km/s, 3.5km/s, 3.7km/s, 3.9km/s. The velocities of the top of the upper mantle are: Vp = 8.1km/s and Vs=4.6km/s. The thickness of the crust is ranging between 42km and 56km. The maximum thickness of the crust in middle Tianshan reaching to 53-56km. There are some low-velocity lens in the middle part of the crust. The results show that the Tianshan mountains are divided into three tectonic zones: northern, central and southern Tianshan, different in the characteristics of the deep crustal structures, and it seems that the formation and the evolution of the Tianshan mountains can be explained with the theory of Surge Tectonics-a new hypothesis of Earth dynamics more resonably then the theory of Plate Tectonics.
A deep-sounding observations by using the PS converted waves of the earthquakes along the rmqi-Korla profile across the Tianshan mountains have been conducted with the cooperation efforts of Chinese, Kazakhstan and Kirghizstan scientists in 1992. As a results a cross-ection of deep crust structures and the velocity models of P and S waves along the profile were obtained. The consolidate crust of the Tianshan mountains is consisted of 4 layers with the velocities of Vp=5.9km/s, 6.3km/s, 6.6km/s, 6.9km/s, Vs=3.2km/s, 3.5km/s, 3.7km/s, 3.9km/s. The velocities of the top of the upper mantle are: Vp = 8.1km/s and Vs=4.6km/s. The thickness of the crust is ranging between 42km and 56km. The maximum thickness of the crust in middle Tianshan reaching to 53-56km. There are some low-velocity lens in the middle part of the crust. The results show that the Tianshan mountains are divided into three tectonic zones: northern, central and southern Tianshan, different in the characteristics of the deep crustal structures, and it seems that the formation and the evolution of the Tianshan mountains can be explained with the theory of Surge Tectonics-a new hypothesis of Earth dynamics more resonably then the theory of Plate Tectonics.
引文
［1］冯先岳，论新疆地震地质特征，地震地质，7（2），35－43，1985．［2］中国大地构造轮廓，地质学报，34，249－255，1954．［3］张文佑，中国大地构造纲要（中国大地构造图说明书），北京：科学出版社，125－174，1959．［4］黄汲清、任纪舜、姜春发等，中国大地构造及其演化，北京：科学出版社，40－46，1980．［5］王作勋、邬继易、吕喜朝等，中国天山大地构造演化概述，中国地质科学院地质研究所所刊，第15号，81－94，1986．［6］陈哲夫、梁云海，新疆天山地质构造几个问题的探讨，新疆地质，3（2），1－12，1985．［7］张良臣、吴乃元，天山地质构造及演化史，新疆地质，3（3），1－13，1985．［8］马瑞士、王赐银、叶尚夫等，东天山构造格架及地壳演化，南京：南京大学出版社，191－205，1993．［9］车自成、刘洪福、刘良等，中天山造山带的形成和演化，北京：地质出版社，58－119，1994．［10］袁学诚、左愚、徐新忠等，阿－阿断面与西夏克拉通，新疆地质科学（第5辑），北京：地质出版社，1－18，1994．［11］邵学钟、张家茹、杨小峰等，利用地震转换波探测地壳上地幔构造试验，地球物理学报，25，89－100，1978．［12］邵学钟、雷兴林、张家布等，天然地震转换波测深，见：汤永安主编，华北平原南部地区深部地球物理综合探测方法与成果，北京：海洋出版社，204－244，1989．［13］张家茹、邵学钟、章思亚等，邢台强震的深部三维构造背景和孕震条件，地震地质，16，319－328，1994．［14］范会吉、邵学钟、张家茹，波形反演方法及其在天山地区转换波测深中的应用，地球物理学报（待发表）．［15］丁国瑜主编，中国岩石图动力学概论，北京：地震出版社，527－538，1991．［16］19－60，1991．
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心