Gravity Data Decomposition Based on Spectral Analysis and Halo Wavelet Transform, Case Study at Bird’s Head Peninsula, West Papua

Abstract

Abstract. Gravity imagery is commonly used in the preliminary study of sedimentary basins. Gravity data have an excellent lateral resolution but poor vertical resolution. The gravity response represents the superposition of all elements of differing density contrasts and depths for a given region below the surface. The ability to perform depth-based gravity data decomposition is important for the interpretation of the data. This can be achieved by combining spectral analysis with the Halo wavelet transform. The decomposition method was tested using synthetic data as well as field data collected at Bird's Head Peninsula, West Papua. Examination of the proposed method using the synthetic data produced satisfactory results that corresponded well to the models. The test using the field data clearly imaged anticline structures that formed due to the ongoing collision of the Australia Continental Plate and the Pacific Oceanic Plate. In part of the Lengguru Fold and Thrust Belt, the folding structures are not imaged at depths greater than ~6 km. We propose that folding structures are not found at deeper levels. The gravity imagery also indicates that the Sorong Fault Zone breaks apart into several segments, which causes other perpendicular lineaments (strike-slip faulting). These strike-slip faults are clearly visible in the Bird's Head Region.

Strike-Slip Fault Identification Beneath of the Wiriagar Oil Field

“…The strike-slip fault delineation in the Wiriagar area is clearly visible based on the gravity data image analysis (Figure 6). This strike-slip fault is similar (match) with the regional structures pattern of the Bird's Head Peninsula derived from depth-based gravity data decomposition (Handyarso & Kadir, 2017). There are several strike-slip faults pattern with southwest (SW) -northeast (NE) direction which is formed due to compressional force from on going collision of Australia Continental Plate with Pacifi c Oceanic Plate as shown in Figure 7.…”

Integrated geophysical approach for ore exploration: Case study of Sidi Bou Aouane–Khadhkhadha Pb–Zn province – Northern Tunisia

“…It consists of a linear filter allowing gravity signal separation in frequency domain (Guo et al., 2013; Rajesh et al., 2020). To get the appropriate wavenumber cut‐off between deep and shallow sources, spectral analysis is used (Arfaoui et al., 2018; Handyarso & Kadir, 2017; Manalo et al., 2016; Rajesh et al., 2020).…”

Optimalisasi Data Gayaberat untuk Pemodelan Struktur Geologi Bawah Permukaan Daerah Kepulauan Sabu-Raijua, Nusa Tenggara Timur, Indonesia

“…Metode gayaberat merupakan metode geofisika yang kerap digunakan dalam studi pendahuluan eksplorasi minyak dan gas. Metode tersebut dapat dengan cepat memetakan kontras densitas secara lateral pada area yang luas [9,10,11,12]. Kondisi geologi daerah penelitian menyebabkan survei seismik tidak cukup memadai, sehingga pemanfaatan data gayaberat diharapkan dapat memberikan kontribusi dalam mengungkap pola struktur geologi bawah permukaan di sekitar daratan Kepulauan Sabu-Raijua.…”