城市活动断层探测中的浅层地震勘探数据库建设——以石嘴山市活动断层探测为例

Database Construction of Shallow Seismic Exploration for Active Fault Detection in Urban Areas: A Case Study of Shizuishan

摘要:

浅层人工地震勘探是城市活断层探测工程中的重要部分。浅层地震勘探数据库记录测点位置、测线分布图、断点位置等详细信息。本文以宁夏石嘴山市活动断层探测为例，重点介绍了针对石嘴山市内四条隐伏断裂所布设的33条浅层地震勘探测线数据库建设的数据库模型、技术方法、操作技巧及注意事项，为城市活断层探测中基于 ArcGIS等平台系统建立浅层地震勘探数据库提供借鉴。

Abstract:

A large number of seismic studies in urban regions show that buried active faults are the culprits for many urban earthquake disasters. Identification of buried active faults is important for managing seismic risk associated with new development in our city.Shallow seismic exploration techniques can reveal concealed fault features，deep distribution status，and nature of activities and other information； therefore，it is an important technique to locate active faults in an urban active fault survey project.A shallow seismic exploration records the position of survey points，distribution of survey lines，location of breakpoints and other details；therefore，it provides important physical data that can be used to explain geological fault models for the urban active fault study.This paper introduces the application of the shallow seismic exploration technique to the city of Shizuishan，and discusses the construction of a shallow seismic exploration database model. It details the technique，processing，and approach for building the database using 33 shallow seismic exploration lines crossing four buried active faults in Shizuishan. The objective of building a shallow seismic exploration database is to reorganize a lot of information provided by the geophysical department，and turn them into binary data based on an ArcGIS system.The construction of the database includes four steps of organizing information （referred to as archive data） including filling attribute data，creating geometry features，importing attribute data，and importing archive data into the database. Archive data are stored in a specific storage space so that users must access them with specific software.The attribute data are filled in using an Excel formatted table and imported in a later step.The geometry features were created and imported into the database using ArcMap.Finally，bulk storage software was used to import attribute data and archive data into the database.This method was practical，quick，and accurate because it simplified database construction and increased work efficiency.The construction of a shallow seismic exploration database should be synchronized with field work. In addition，at the end of database construction，the primitive data map and fault distribution map should be updated and stored in the completed shallow seismic exploration database.The database is delivered to and tested by the center for management，where data can be concurrently shared for surveying and prospecting of active faults and corrected based on the test reports.