Claim Missing Document
Check
Articles

Found 5 Documents
Search

Analysis Of The Audio-Magnetotelluric (AMT) Data Quality Using The Coherence Parameter at Malabar Mountains Kusuma, Nabila Putri; Rahmawati, Nabilah; Hanifah, Shofie Dzakia; Harja, Asep; Lucki Junursyah, Gusti Muhammad
Phi: Jurnal Pendidikan Fisika dan Terapan Vol 10, No 2 (2024)
Publisher : Universitas Islam Negeri Ar-Raniry

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22373/p-jpft.v10i2.24360

Abstract

Noise recorded during measurements can diminish the quality of AMT data. This can lead to decreased penetration depth and unreliable 1D inversion models. This study aimed to reduce noise and improve data quality by analyzing coherence, curve trend, and skewness. Coherence analysis was performed using robust processing and XPR editing, yielding an average coherence value of 77.5%, an improvement of 10.8% from the raw data. Noise can also alter data dimensionality; hence, skewness analysis was used to determine the effect of distortion on the impedance tensor. Results showed that the 3D dimensionality effect at 6 stations was significantly reduced following coherence and curve trend analyses.
Geophysical Investigation of Buried Small Fault Beneath Western Mount Malabar Using Electrical Resistivity Tomography in The Great Bandung Basin Rim Susanto, Kusnahadi; Harja, Asep; Ma’arif, Farham Rezqi; Mukhtar, Husneni
Indonesian Journal on Geoscience Vol. 11 No. 3 (2024)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.11.3.409-421

Abstract

This article presents the discovery of a buried fault beneath the soil layers in the Mt Malabar area, which complements the information on suspected faults on the previous geological maps. Using an Electrical Resistivity Tomography (ERT) method, this study aims to delineate the layer discontinuity as a fault and describe the subsurface geology. This study employed a 1400 m long ERT line as the main line to identify buried fault traces, while each ERT line has an 800 m long installation across the main ERT line to obtain the direction of the minor fault. The investigation found a minor fault in the rock layer at a high resistivity layer, approximately 160 m below the surface. The identified rock units are believed to include sandy clay in the upper layer, followed by tuff, sandstone, and basalt lava in the lower layer because its resistivity value is above 250 Ohm.m. The 3D ERT model interpreted a minor buried fault as a weak zone beneath the soil and obtained the fault strike at approximately N 310°E and dipping 66°. Furthermore, these results are strengthened by the geological map, which confirms that ERT L-1 and ERT L-3 profiles coincide with a suspected fault in the Qmt rock unit area.
INVESTIGASI LAPISAN BATUAN KAWASAN PENDIDIKAN UNIVERSITAS PADJADJARAN JATINANGOR BAGIAN UTARA BERDASARKAN ELECTRICAL RESISTIVITY TOMOGRAPHY (ERT) Susanto, Kusnahadi; Azzam, Muhammad Zharfan; Syarafina, Zhafirah Nurul; Kirana, Kartika Hajar; Dharmawan, Irwan Ary; Harja, Asep
Bulletin of Scientific Contribution Vol 21, No 2 (2023): Bulletin of Scientific Contribution : GEOLOGY
Publisher : Fakultas Teknik Geologi Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/bsc.v21i2.48042

Abstract

Pemeriksaan lapisan batuan serta kondisi bawah permukaan memegang peran yang sangat penting dalam upaya pemanfaatan lahan, baik untuk mendukung infrastruktur diatasnya maupun pemanfaatan sumber daya alam yang terkandung didalamnya. Pemanfaatan lahan berhubungan erat dengan pengembangan infrastruktur yang direncanakan. Agar dapat mengurangi risiko potensial dari bencana, penting untuk memperhatikan kualitas dan kemampuan dukungan lahan yang diperlukan. Artikel ini mengulas tentang hasil studi mengenai identifikasi lapisan batuan yang dilakukan kampus Universitas Padjadjaran Jatinangor di bagian utara. Metode yang digunakan dalam penelitian ini adalah metode Electrical Resistivity Tomography (ERT) karena merupakan metode yang memiliki resolusi yang baik dalam pengukuran geofisika dangkal. Data yang dihasilkan dari pengukuran ini adalah penampang kontras resistivitas tanah dan batuan yang berasosiasi pada berbagai aspek seperti kandungan air dalam pori, jenis batuan serta struktur bawah permukaan. Pengukuran ERT dilakukan dengan membuat 11 lintasan baik yang saling memotong maupun saling sejajar. Hasil pengukuran geolistrik resistivitas di daerah penelitian ini menunjukkan variasi kontras tahanan jenis batuan mulai dari 0,5 Ωmeter sampai lebih dari 500 Ωmeter, namun demikian dalam interpretasi yang kami lakukan, rentang nilai tersebut dibagi menjadi beberapa rentang kategori yang disesuaikan dengan maksud penelitian serta kondisi lapangan yang sedang diteliti. Hasil interpretasi terhadap data resistivitas memunculkan informasi dugaan tiga lapisan batuan di antara kedalaman 0 sampai dengan 70 dan struktur patahan minor di sekitar daerah penelitian.  
Identification of Deep Aquifer Depth in Lava Fan Area, Haruman Peak, Malabar Mountains Based on Audio Magnetotelluric Sounding HARJA, ASEP
JIIF (Jurnal Ilmu dan Inovasi Fisika) Vol 9, No 2 (2025)
Publisher : Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/jiif.v9i2.65355

Abstract

Haruman Peak, located in the southern region of the Bandung Basin, is one of the summits of the Malabar Mountains. This mountain range functions as a significant recharge area for the Bandung-Soreang Groundwater Basin, a role supported by its dense vegetation cover, high precipitation, and slopes that facilitate direct runoff into the basin. Previous studies have identified the presence of shallow aquifers in the Haruman Peak area at depths of less than 40 meters. This study aims to investigate the existence of deeper aquifer systems in the Haruman Peak area using the Audio-Magnetotelluric (AMT) method. AMT data were acquired at three measurement points located on the northern side of a suspected fault zone. The inversion of the AMT data yielded one-dimensional (1D) resistivity models that provide insight into the subsurface structure. These models were used to interpret the lithological composition and to delineate potential aquifer zones. The subsurface stratigraphy in the study area is interpreted to consist of soil, Malabar–Tilu Volcanics (Qmt), and the Waringin–Bedil Andesite Formation, also referred to as Old Malabar (Qwb). The results indicate the presence of deep aquifers at measurement points MB-01 and MB-02, at estimated depths of approximately 1,322 meters and 804 meters, respectively. At point MB-03, a shallow aquifer was identified within a soil layer at a depth of less than 100 meters.
KARAKTERISASI LAPISAN BAWAH PERMUKAAN LERENG HASIL PERGERAKAN SESAR LEMBANG MENGGUNAKAN ELECTRICAL RESISTIVITY TOMOGRAPHY PADA SAG POND MURIL Aliyan, Silmi Afina; Susanto, Kusnahadi; Pamungkas, Totok Doyo; Ihsan, Haikal Muhammad; Harja, Asep; Fitriani, Dini; Rosandi, Yudi
Jurnal Geosaintek Vol. 11 No. 2 (2025)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25023659.v11i2.2224

Abstract