P-S waves 3D velocity model of Los Humeros area from earthquake based travel-time tomography using CAT3D software (OGS)

The dataset contains the 3D velocity model (VP (m/s), VS (m/s) and VP/VS) obtained from the tomographic inversion of seismological data in the area of Los Humeros (Mexico). The model was performed in the frame of the GEMex project (Mexico‐Europe Cooperation for research of enhanced geothermal systems and super-hot geothermal systems, WP5 ‘Detection of deep structures’, Jousset et al., D5.3, 2019). The inversion used 2661 P arrivals and 2272 S arrivals associated to 395 earthquakes recorded by 37 stations. The picking data was provided by Toledo et al., 2019. The inversion was performed by CAT3D software, a tomographic tool developed by OGS, which uses the SIRT method (Simultaneous Iterative Reconstruction Technique, Stewart, 1993) as inversion algorithm and the ray tracing procedure based on minimum time principle (Böhm et al., 1999). The velocities used as initial model for tomography were provided by the interpolated values obtained from the velocity analysis of four 2D seismic lines acquired inside the same investigated area by the tomographic inversion (See GEMex deliverable D5.3). The 3D velocity model is defined by a 3D grid of 61 nodes in X, 69 nodes in Y and 29 nodes in Z, equally spaced by 250 m in all directions. The total dimensions of the model is 15x17x7 km and the borders positions are (m) (WGS 84/UTM ZONE 14N): Xmin = 655000, Xmax = 670000 Ymin = 2168000, Ymax = 2185000 Zmin = -3000, Zmax = 4000本数据集包含源自墨西哥洛斯乌梅罗斯（Los Humeros）地区地震数据层析成像反演（tomographic inversion）得到的三维速度模型，涵盖纵波速度VP（单位：m/s）、横波速度VS（单位：m/s）以及VP/VS比值。该模型依托GEMex项目框架完成，此项目为墨西哥-欧洲增强地热系统与超高温地热系统研究合作项目，对应工作包5「深部结构探测」，相关成果详见Jousset等人2019年发布的交付物D5.3。本次反演共使用2661个P波初至与2272个S波初至，这些初至关联了395次地震事件的观测数据，由37个地震台站记录完成，初至拾取数据由Toledo等人2019年提供。反演采用OGS开发的CAT3D软件完成，该层析成像工具以SIRT法（同步迭代重建技术，Simultaneous Iterative Reconstruction Technique，Stewart, 1993）作为反演算法，并采用基于最小走时原理的射线追踪方法（Böhm等人, 1999）。本次层析成像所用的初始速度模型，由对同一研究区内采集的4条二维地震测线开展速度分析后得到的插值结果提供，详见GEMex项目交付物D5.3。该三维速度模型由三维网格定义，X、Y、Z方向分别包含61、69、29个节点，各方向节点间距均为250米。模型总尺寸为15×17×7 km，边界坐标采用WGS 84/UTM ZONE 14N坐标系，具体参数如下：X最小值655000 m，X最大值670000 m；Y最小值2168000 m，Y最大值2185000 m；Z最小值-3000 m，Z最大值4000 m。