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On February 17, 1996, at 05:59:30 UTC there was an Mw 8.1 earthquake. Besides, it caused a tsunami. This event occurred in the northern part of the Cendrawasih Bay, where the New Guinea Thrust segment had a relatively low average slip velocity. To obtain a finite fault, waveforms from a tele-station located 30-90 degrees are used. The far-field body wave equation is used and inverted by the Kikuchi-Kanamori algorithm. In addition to obtaining source parameters, this study also aims to determine the value of the rupture velocity that occurs during coseismic events. From this research was found that the rupture velocity (vr) was 2.5 km/s, which occurred at a depth of 13.7 km. The largest value of vector slip is 2.31 m, with an average slip value of 0.922 m. The dimension area of the fault has a size of 272 km × 110 km. The seismic moment obtained is 1.5 × 1021 Nm, which is equivalent to Mw 8.1. This study also found a variance of 0.2844 in the use of the P and SH wave components, which is the smallest variance from the use of the P, P and SH, and SH components in the Kikuchi-Kanamori Program.

Palu City is composed of sedimentary rocks so that it has a high level of vulnerability when an earthquake occurs. The earthquake that occurred on September 28, 2018, 25 km north of Donggala with a magnitude of 7.4 Mw, had caused a tsunami that struck Palu City, Sigi Regency, Donggala Regency, and Parigi Mouthong Regency, Central Sulawesi Province. This earthquake also caused liquefactions in the Petobo and Balaroa areas, Palu City, and Jono Oge in Sigi Regency. In this study, the authors used microtremor data at 8 points measured before and after the earthquake. Processing using the Horizontal to Vertical Spectra Ratio method shows that the predominant frequency and amplification factor changes due to changes in local rock conditions. The analysis also shows the value of soil vulnerability index (Kg) mostly increased after the earthquake. Besides, the elliptic curve inversion method shows that before the earthquake event, the value of the S wave velocity (Vs30) in layer one was between 157.1-211.4 m/sec with a layer thickness between 65.3-90.6 meters, while after the earthquake, the velocity becomes 156-214.6 m/sec with a layer thickness ranging between 66-99.2 meters. This indicates that the area consists of soft and medium soils, which subsequently increased sediment thickness in most areas after the earthquake.

Emas merupakan salah satu komoditas mineral yang mempunyai harga jual yang cukup tinggi. Indonesia memiliki banyak wilayah yang menyimpan deposit emas di bawah permukaan. Satu di antaranya adalah wilayah Poboya, Kecamatan Mantikulore, Palu. Metode pemetaan deposit emas yang dapat digunakan adalah seismik pasif contohnya mikrotremor. Salah satu teknik pengolahan dari metode seismik pasif adalah Horizontal to Vertical Spectral Ratio (HVSR). HVSR mencerminkan kondisi struktur lapisan di atas batuan dasar. Hasil pemodelan menunjukkan bahwa potensi deposit emas terdapat di wilayah Timur hingga Selatan Poboya. Potensi terbesar terletak di Selatan bagian tersebut. Potensi deposit emas dapat ditemukan pada kedalaman sekitar 300 hingga 1500 meter di bawah permukaan. Analisis potensi tersebut didasarkan ditemukannya anomali lapisan dengan nilai kecepatan gelombang geser (Vs) yang tinggi, berkisar pada rentang nilai 3500-4000 m/s yang bersesuaian dengan batuan beku yang diduga endapan epitermal emas. Hasil pemodelan divalidasi dengan penelitian terdahulu yang memiliki kemiripan. Berdasarkan hasil tersebut menunjukkan bahwa metode inversi HVSR berdasarkan rekaman mikrotremor dapat dijadikan metode awal pendugaan deposit emas yang lebih efektif dan efisien.