厚覆盖层地区隐伏活断层探测的地震方法技术——以桥北镇—宿迁断层为例
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摘要
地震反射勘探法是当前城市地震活断层探测的主要方法,它在厚覆盖区探测断层及其上断点的效果取决于所采用的工作方法和技术参数。桥北镇—宿迁断裂是郯庐断裂带在江苏境内一条重要的隐伏断裂。以宿迁市活动断层探测项目中针对该断裂敷设于厚覆盖层地区的QL14测线为例,为了查明测线控制地段内断裂的空间展布形态、性质以及活动性,针对不同目标、目的层深度和精度要求,作者按照组合、分步探测的工作思路,采用了不同的地震勘探方法技术和采集参数对其进行了高分辨率地震反射成像,解决了地质任务要求与野外资料采集方法之间的矛盾,从而获得了埋深约16~450 m范围内高分辨率的地层结构和非常清晰的断裂构造图像,为钻孔联合剖面位置的布设、钻孔深度的设计以及断裂活动性的评价提供了地震学依据。最后经高精度钻孔联合地质剖面证实,地震勘探方法反演得到的主要地层界面和构造特征都与钻孔联合地质剖面吻合较好。试验结果表明:采用组合探测的方法能够获得断层在不同深度的产状、展布以及由深至浅完整的分布图像;地震勘探法在厚覆盖区确定隐伏断层具体位置和判定断层活动性具有可行性以及地震勘探与钻孔联合地质剖面相结合的工作方法具有有效性。
Seismic reflection exploration is the main technique in present urban active faults detecting. The effect of investigating fault and its up-breakpoint in thick Quaternary sediments depends on the working methods and technical parameters. Qiaobei-Suqian fault is an important buried fault along Tan-Lu fault zone in Jiangsu. In this paper,based on QL14 line laid on the fault in thick sediments during the active fault survey in Suqian City and aimed at investigating the spatial distribution,characteristics and activities of the fault controlled by the line,the authors used different seismic exploration methods and acquisition parameters to perform a high-resolution seismic reflection experiment and obtain the imaging of buried fault in the light of the work thinking of combination and fractional steps and according to different targets,the depth of the target layer and the accuracy requirement. The technique solved the contradiction between the field data acquisition and the geological task. The authors obtained high-resolution images of structures in the depths of 16 ~ 450 m after data processing,and the prospecting results provide seismological evidence for the position layout of composite drilling sections,the depth designing of drilling and the evaluation of fault activity. The high-precision composite drilling geological sections show that the main stratigraphic boundaries and tectonic features obtained from the seismic exploration methods are quite consistent with the results from the composite drilling geological section. The experimental result shows that the combined detection methods can receive the attitude and distribution of the fault in different depths and the complete distribution image from the depth to the shallow part of the fault. The feasibility of the seismic exploration methods for locating the buried fault and determining its activity in thick Quaternary sediments and the efficiency of the combination of seismic exploration and composite drilling geological profiles are also demonstrated in this study.
引文
[1]中国地震局.活断层探测方法[M].北京:地震出版社,2005.
    [2]Shtivelman V,Frieslander U,Zilberman E,et al.Mapping shallow faults at the Evrona playa site using high-resolution reflection method[J].Geophysics,1998,63(4):1257-1264.
    [3]邓起东,徐锡伟,张先康,等.城市活动断裂探测的方法与技术[J].地学前缘,2003,10(1):93-101.
    [4]吴子泉,刘元生,刘保金,等.地球物理方法在城市地震活动断层精确定位中的应用[J].地球物理学进展,2005,20(2):528-533.
    [5]刘保金,姬继法,徐朝繁,等.共偏移距地震反射波方法用于城市活断层探测[J].地震地质,2006,28(3):411-418.
    [6]刘保金,柴炽章,酆少英,等.第四纪沉积区断层及其上断点探测的地震方法技术—以银川隐伏活动断层为例[J].地球物理学报,2008,51(5):1475-1483.
    [7]赵富有,王世煜,王典.横波地震勘查技术在长春市活断层探测中的应用[J].地球物理学进展,2008,23(1):284-288.
    [8]李大虎,何强,邵昌盛,等.综合地球物理勘探在青川县城区活动断层探测中的应用[J].成都理工大学学报:自然科学版,2010,37(6):666-672.
    [9]顾勤平,康清清,许汉刚,等.薄覆盖层地区隐伏断层及其上断点探测的地震方法技术—以废黄河断层为例[J].地球物理学报,2013,56(5):1609-1618.
    [10]方盛明,张先康,刘保金,等.大城市活断层探测的地球物理方法[J].地震地质,2002,24(4):606-613.
    [11]徐明才,高景华,刘建勋,等.应用于城市活断层调查的地震方法技术[J].中国地震,2005,21(1):17-23.
    [12]方盛明,张先康,刘保金,等.城市活断层地震勘探的最佳组合方法与应用研究[J].地震地质,2006,28(4):643-654.
    [13]柴炽章,孟广魁,杜鹏,等.隐伏活动断层的多层次综合探测—以银川隐伏活动断层为例[J].地震地质,2006,28(4):536-546.
    [14]Williams R A,Odum J K,Pratt T L,et al.Seismic surveys assess earthquake hazard in the New Madrid area[J].The leading Edge,1995,14:30-34.
    [15]中国地震局.中国地震活动断层探测技术系统技术规程[M]..北京:地震出版社,2005
    [16]江苏省地震工程研究院.《宿迁市活动断层探测与地震危险性评价》子专题4隐伏断层的控制性人工地震探测成果报告[R].南京,2013.
    [17]刘保金,胡平,陈顒,等.北京平原西北部地壳浅部结构和隐伏活动断裂—由地震反射剖面揭示[J].地球物理学报,2009,52(8):2015-2025.
    [18]王庆海,徐明才.抗干扰高分辨率浅层地震勘探[M].北京:地质出版社,1991.
    [19]王振东.浅层地震勘探技术[M].北京:地质出版社,1988.
    [20]渥·伊尔马滋.地震数据处理[M].黄续德,袁明德,译.北京:石油工业出版社,1994.

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