AusPASS - Mount Isa Northern Queensland (MINQ)

AusPass is a service dedicated to the acquisition, management, and distribution of passive seismological data in Australia. Extensive fieldwork projects are conducted across the country, organized in seismic arrays (i.e. groups of seismic stations). The MINQ experiment was conducted by the Australian National University and the Geological Survey of Queensland as part of the AuScope Infrastructure program, and involved setting up an array of portable earthquake recorders on a rectangular grid with approximately 50km spacing, beginning in the Mount Isa area. Instruments are ANU solid state recorders and Lennartz 3Dlite-MII seismometers.The instruments recorded seismic waves passing through the Earth from distant earthquakes in the Pacific, Indian and Southern Oceans. By comparing the signals and their arrival times at different sites it is possible to learn about the geological history of North Queensland from structures we can see deep in the crust. We can resolve these seismic velocity changes in this way down as far as 50 to 100km depth. The images are constructed from the travel times of seismic waves using ray tracing and seismic tomography.An initial 21 instruments were installed in the Mount Isa area in June 2009 as the first phase of a deployment that moved progressively to the east over several years. The network was expanded to 25 instruments when the first data was collected on an instrument service run in September. Most of the instruments were moved in late 2010 to the second phase of the experiment, MINQ-B, is installed on the plains east of Cloncurry.AusPass是专注于澳大利亚境内被动地震数据（passive seismological data）采集、管理与分发的服务平台。该项目在澳大利亚全境开展大规模野外作业，以地震台阵（seismic arrays，即地震台站群组）为基本组织单元实施。 MINQ实验由澳大利亚国立大学与昆士兰州地质调查局联合开展，隶属于AuScope基础设施计划，其核心内容为在以芒特艾萨（Mount Isa）地区为起始点的矩形网格中布设便携式地震记录仪，网格间距约50千米。本次实验所用仪器为ANU固态记录仪与Lennartz 3Dlite-MII型地震仪。上述仪器可记录源自太平洋、印度洋及南大洋远震事件的穿透地球内部的地震波。通过对比不同台站的地震信号及其到达时刻，我们能够依据地壳深部构造解析昆士兰州北部的地质演化历史。借助该方法，我们可对深度达50至100千米范围内的地震波速度变化实现分辨。研究图像通过射线追踪（ray tracing）与地震层析成像（seismic tomography）技术，基于地震波走时数据构建而成。 2009年6月，首批21台仪器在芒特艾萨地区完成布设，作为该台阵部署的第一阶段，后续数年间台阵逐步向东延伸。同年9月，在首次仪器运维作业中完成首批数据采集后，台站网络扩容至25台仪器。2010年末，绝大多数仪器被搬迁至实验第二阶段MINQ-B的布设场地，该场地坐落于克隆柯里（Cloncurry）东部的平原区域。