Analisis Seismisitas dan Mekanisme Fokus Sesar Sumatera: Studi Kasus Segmen Semangko dan Selat Sunda
DOI:
https://doi.org/10.23960/jtii.v5i2.98Abstract View: 487
Abstract
Penelitian ini bertujuan untuk menganalisis seismisitas dan mekanisme fokus di wilayah Sesar Semangko dan Sesar Sunda, yang terletak di daerah aktif tektonik Indonesia. Dengan merelokasi 1,464 gempa bumi dari tahun 2010 hingga 2023, kami menemukan pola distribusi gempa yang lebih terfokus, terutama di sekitar Sesar Semangko. Nilai RMSCT rendah dan Conditional Number (CN) dalam rentang 59–80 menunjukkan stabilitas dan akurasi hasil. Dua kluster gempa teridentifikasi, satu di Teluk Semangko dan satu di bagian selatan, yang mendorong analisis lebih lanjut menggunakan inversi momen tensor. Hasil inversi menunjukkan dominasi aktivitas tektonik dengan proporsi 67,2% untuk Double-Couple (DC) dan 32,8% untuk Compensated Linear Vector Dipole (CLVD), serta mengonfirmasi tipe sesar sebagai strike-slip dengan arah 350°, kemiringan 55°, dan rake 179°. Penyelidikan stres prinsipal menunjukkan adanya kesamaan mekanisme antara segmen Semangko dan Sunda, yang memperlihatkan arah regangan yang halus. Temuan ini memperdalam pemahaman mengenai interaksi sesar aktif di Indonesia dan implikasinya terhadap keselamatan masyarakat. Penelitian lebih lanjut diperlukan untuk mengeksplorasi lebih dalam dinamika seismik di wilayah ini.Downloads
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