earthquake and tectonic studies Open access Peer reviewed

Statistical Analysis of Seismicity in West Sumatra (2015–2025) and Aftershock Decay of the 2009 Padang Earthquake Using Gutenberg–Richter and Omori–Utsu Laws

Icha Untari Meidji, Nur Afni Oktavia Nusi, Harsono Jayadi

KONSTAN - JURNAL FISIKA DAN PENDIDIKAN FISIKA | Jul 4, 2026

Abstract

Abstract

Previous studies on seismicity in West Sumatra have generally focused either on frequency–magnitude distribution or aftershock decay separately, with limited integration of updated earthquake catalogs and combined statistical approaches. This study examines the seismicity of West Sumatra using the Gutenberg–Richter (GR) law and the Omori–Utsu aftershock decay model for the 30 September 2009 Padang earthquake. Earthquake catalogs from the United States Geological Survey (USGS) covering the last ten years and the aftershock sequence of the 2009 event were analyzed. The GR law was applied through cumulative frequency–magnitude distributions to estimate the a- and b-values, which represent seismic activity level and magnitude distribution. The Omori–Utsu model was used to determine the decay parameter p and the initial aftershock activity constant K. The results show a strong linear frequency–magnitude relationship with a relatively high b-value, indicating dominant small- to moderate-magnitude earthquakes and high seismicity. Aftershock activity follows the Omori–Utsu decay pattern with a moderately slow decay rate. These results emphasize the influence of subduction zone dynamics and provide important implications for earthquake hazard mitigation in West Sumatra. These results provide updated seismic parameters for West Sumatra, support regional seismic hazard modeling, and contribute to refining empirical parameter estimation for the Sunda subduction setting.

Direct answer

What can I do from this paper page?

Use this page to scan "Statistical Analysis of Seismicity in West Sumatra (2015–2025) and Aftershock Decay of the 2009 Padang Earthquake Using Gutenberg–Richter and Omori–Utsu Laws" quickly: start with the summary and abstract, then check the authors, source, topics, and related papers. From here, open Scollr to follow earthquake and tectonic studies research, save the paper, or map adjacent work.

Authors

Researchers on this paper

Icha Untari Meidji

first | State University of Gorontalo | ORCID 0000-0002-3719-1758

Nur Afni Oktavia Nusi

middle | State University of Gorontalo

Harsono Jayadi

last | Tadulako University

Research areas

Follow related topics

Citation

BibTeX

@article{Meidji2026Statistical,
  title = {Statistical Analysis of Seismicity in West Sumatra (2015–2025) and Aftershock Decay of the 2009 Padang Earthquake Using Gutenberg–Richter and Omori–Utsu Laws},
  author = {Icha Untari Meidji and Nur Afni Oktavia Nusi and Harsono Jayadi},
  journal = {KONSTAN - JURNAL FISIKA DAN PENDIDIKAN FISIKA},
  year = {2026},
  doi = {10.20414/konstan.v11i01.926},
  url = {https://doi.org/10.20414/konstan.v11i01.926}
}

FAQ

Using this paper in a discovery workflow

How do I find related work for this paper?

Use the related papers and topic links on this page as starting points. In Scollr, you can also open the paper and build a literature map around its references, citing papers, and related work.

How can I keep up with new earthquake and tectonic studies research papers?

Follow earthquake and tectonic studies research in Scollr. New papers from the topic flow into a personalized feed, and you can save useful studies to revisit later.

Can I cite this paper from this page?

This page includes a static BibTeX block for Statistical Analysis of Seismicity in West Sumatra (2015–2025) and Aftershock Decay of the 2009 Padang Earthquake Using Gutenberg–Richter and Omori–Utsu Laws. Always verify the DOI, source, and publication details against the publisher record before submitting a manuscript.

Follow this research in Scollr

Follow the topics and authors behind this paper, save useful studies, and build a literature map when you are ready to go deeper.

Get the app