Localized global positioning system derived strain map of Malaysia

Located on the Sunda tectonic block which encompasses a major part of the Southeast Asia region, Malaysia was considered lying in a relatively safe zone, as events caused by tectonic plate movement such as earthquakes, tsunamis and volcanic eruptions had never hit her. However, several regional eart...

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Main Author: Johari, Nini Nurdiana
Format: Thesis
Language:English
Published: 2020
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Online Access:http://eprints.utm.my/id/eprint/98259/1/NiniNurdianaJohariMFABU2020.pdf
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spelling my-utm-ep.982592022-11-23T08:41:47Z Localized global positioning system derived strain map of Malaysia 2020 Johari, Nini Nurdiana G109.5 Global Positioning System Located on the Sunda tectonic block which encompasses a major part of the Southeast Asia region, Malaysia was considered lying in a relatively safe zone, as events caused by tectonic plate movement such as earthquakes, tsunamis and volcanic eruptions had never hit her. However, several regional earthquakes such as the Sumatra-Andaman, Nias, Bengkulu and the most recent Sabah earthquake have resulted in a long-term post-seismic deformation within the Sunda plate; these entail the need for Malaysia to have seismic hazard assessment for the prediction of risks attached to possible future earthquakes in the country. Strain or deformation at the earth’s surface is often a consequence of large-scale tectonic forces such as earthquakes. When earthquakes happen, the accumulated strain on the crust is released, thus the strain rate can proxy for earthquake potential. This study aims to characterize the state of current seismic deformation in Malaysia through three objectives: 1) to estimate Global Positioning System (GPS) velocity vectors from the Continuously Operating Reference Station (CORS) network; 2) to generate localized GPS-derived strain map of Malaysia, and 3) to assess the GPS-derived strain map from seismic data. Three research methodologies were adopted to achieve these objectives. The first phase of the study estimated velocity vectors using linear least squares regression analysis from the time series of daily solutions of 88 CORS throughout Malaysia over a period of 7 years from 2010 to 2016. It is found that Peninsular Malaysia moves south-east at an average velocity of -0.43 ±0.09 cm/year for the north component, and 2.90 ±0.22 cm/year for the east component. Meanwhile, Sabah and Sarawak also move south-east at an average velocity of -1.07 ±0.09 cm/year for the north component and 2.50 ±0.02 cm/year for the east component. In the second phase, continuous strain field patterns over the Malaysia region were generated by employing the least square collocation technique. Extension and shortening strain up to 300 nanostrain/year is found in Peninsular Malaysia while extension and shortening strain up to 230 nanostrain/year is found in Sabah and Sarawak. For the final phase, the reliability of the GPS-derived strain map was verified from the estimated strain rate from seismic moment tensor. There is a good correlation between the strain rates obtained from seismic data and the strain rates estimated from GPS. The extension and shortening strain rates show slightly similar results, except for the azimuth which shows slightly different direction in the range of 120-190. In conclusion, the analysis of the localized strain can provide important information on active faults and also ongoing internal plate deformation for seismic hazard assessment in Peninsular Malaysia and Sabah and Sarawak. 2020 Thesis http://eprints.utm.my/id/eprint/98259/ http://eprints.utm.my/id/eprint/98259/1/NiniNurdianaJohariMFABU2020.pdf application/pdf en public http://dms.library.utm.my:8080/vital/access/manager/Repository/vital:144544 masters Universiti Teknologi Malaysia, Faculty of Built Environment & Surveying Faculty of Built Environment & Surveying
institution Universiti Teknologi Malaysia
collection UTM Institutional Repository
language English
topic G109.5 Global Positioning System
spellingShingle G109.5 Global Positioning System
Johari, Nini Nurdiana
Localized global positioning system derived strain map of Malaysia
description Located on the Sunda tectonic block which encompasses a major part of the Southeast Asia region, Malaysia was considered lying in a relatively safe zone, as events caused by tectonic plate movement such as earthquakes, tsunamis and volcanic eruptions had never hit her. However, several regional earthquakes such as the Sumatra-Andaman, Nias, Bengkulu and the most recent Sabah earthquake have resulted in a long-term post-seismic deformation within the Sunda plate; these entail the need for Malaysia to have seismic hazard assessment for the prediction of risks attached to possible future earthquakes in the country. Strain or deformation at the earth’s surface is often a consequence of large-scale tectonic forces such as earthquakes. When earthquakes happen, the accumulated strain on the crust is released, thus the strain rate can proxy for earthquake potential. This study aims to characterize the state of current seismic deformation in Malaysia through three objectives: 1) to estimate Global Positioning System (GPS) velocity vectors from the Continuously Operating Reference Station (CORS) network; 2) to generate localized GPS-derived strain map of Malaysia, and 3) to assess the GPS-derived strain map from seismic data. Three research methodologies were adopted to achieve these objectives. The first phase of the study estimated velocity vectors using linear least squares regression analysis from the time series of daily solutions of 88 CORS throughout Malaysia over a period of 7 years from 2010 to 2016. It is found that Peninsular Malaysia moves south-east at an average velocity of -0.43 ±0.09 cm/year for the north component, and 2.90 ±0.22 cm/year for the east component. Meanwhile, Sabah and Sarawak also move south-east at an average velocity of -1.07 ±0.09 cm/year for the north component and 2.50 ±0.02 cm/year for the east component. In the second phase, continuous strain field patterns over the Malaysia region were generated by employing the least square collocation technique. Extension and shortening strain up to 300 nanostrain/year is found in Peninsular Malaysia while extension and shortening strain up to 230 nanostrain/year is found in Sabah and Sarawak. For the final phase, the reliability of the GPS-derived strain map was verified from the estimated strain rate from seismic moment tensor. There is a good correlation between the strain rates obtained from seismic data and the strain rates estimated from GPS. The extension and shortening strain rates show slightly similar results, except for the azimuth which shows slightly different direction in the range of 120-190. In conclusion, the analysis of the localized strain can provide important information on active faults and also ongoing internal plate deformation for seismic hazard assessment in Peninsular Malaysia and Sabah and Sarawak.
format Thesis
qualification_level Master's degree
author Johari, Nini Nurdiana
author_facet Johari, Nini Nurdiana
author_sort Johari, Nini Nurdiana
title Localized global positioning system derived strain map of Malaysia
title_short Localized global positioning system derived strain map of Malaysia
title_full Localized global positioning system derived strain map of Malaysia
title_fullStr Localized global positioning system derived strain map of Malaysia
title_full_unstemmed Localized global positioning system derived strain map of Malaysia
title_sort localized global positioning system derived strain map of malaysia
granting_institution Universiti Teknologi Malaysia, Faculty of Built Environment & Surveying
granting_department Faculty of Built Environment & Surveying
publishDate 2020
url http://eprints.utm.my/id/eprint/98259/1/NiniNurdianaJohariMFABU2020.pdf
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