Data for 3D P-wave Velocity Model beneath Peninsular Malaysia and Singapore

Published: 20-03-2020| Version 1 | DOI: 10.17632/b7cwrt82m6.1
Abel Osagie


The research obtained 3D velocity model beneath Peninsular Malaysia and Singapore by using p-wave arrival-times from local and regional earthquakes that have occurred within and around the Sumatra Subduction Zone. Earthquake data used in the study is obtained from two sources 1. Waveform data from Incorporated Research Institutions for Seismology (IRIS) 2. Arrival-time dataset from the bulletin of International Seismological Center (ISC). The selection criteria for the earthquakes are, latitude 10 degrees North to 10 degrees South, longitude 92 to 114 degrees East, focal depths < 100 km and magnitude (mb) > 3.0. The combined dataset can be found in "DATASET" The 3D velocity model obtained can be found in "PENISULAR-MODEL-3D.TXT" file. There are 13, 10 and 10 points along the latitude, longitude and depth directions respectively, making 1,300 grid points in the model volume. Latitude range: 1.0º N to 7.0º N at 0.5º interval Longitude range: 100.0º E to 104.5º E at 0.5º interval. Depth range: 1 to 40 km. The file consist of five columns, LON, LAT, Z, VPB and V, which represent longitude (deg), latitude(deg), depth(km), perturbation (%) and p-wave velocity (km/s). Other files include: PENISULAR-DEP-SLICE.TXT- Nine representative depth cross-sections. PENISULAR-LAT-SLICE.TXT- Thirteen East-West vertical cross-sections. PENISULAR-LON-SLICE.TXT- Ten North-South vertical cross-sections. PENISULAR-EVENTS.TXT- Hypocentral Parameters used for the tomographic inversion PENISULAR-AVE-RES.TXT- the average traveltime residual values based on the iasp91 velocity model at four azimuthal angles (NE, SE, SW and NE) PENISULAR-RESIDUALS.TXT- the actual residual values based on computation from the study in comparison with the result published by the ISC


Steps to reproduce

1. Download waveform data from IRIS free online datacenter with JWEED software. 2. Download arrival time dataset as ASCII files from the bulletin of International Seismological Center 3. Pick phase from the waveform data with SEISAN software 4. Combine both datasets (with an algorithm developed in this study) 4. Compute travel times and residual values (with an algorithm developed in this study) 5. Perform tomographic inversion and obtain 3D velocity model