https://jgsm.geologi.esdm.go.id/index.php/JGSM <p><strong>Jurnal Geologi dan Sumberdaya Mineral (Journal of Geology and Mineral Resources)</strong> is an Indonesian scientific journal published by the Center for Geological Survey, Geological Agency, Ministry of Energy and Mineral Resources. The journal receives Indonesian or English articles. Those articles are selected and reviewed by our professional editors and peer reviewers.</p> <p>JGSM has been assigned as an Accredited Scientific Periodical Magazine by the Indonesian Institute of Sciences (LIPI) No. 596/Akred/P2MI-LIPI/03/2015 in 2015, followed by Kementerian Riset dan Teknologi / Badan Riset dan Inovasi Nasional No. 200/M/KPT/2020 in 2020. The journal is indexed in <a title="portal_garuda_IPI" href="http://id.portalgaruda.org/?ref=browse&amp;mod=viewjournal&amp;journal=10104" target="_blank" rel="noopener">Indonesian Publication Index (IPI)</a>, <a title="isjd" href="http://isjd.pdii.lipi.go.id/index.php/public_no_login/index_direktori" target="_blank" rel="noopener">Indonesian Scientific Journal Database (ISJD)</a>, <a href="http://dx.doi.org/10.33332">Digital Object Identifier (DOI)</a> and <a title="google_scholar" href="https://scholar.google.co.id/citations?user=nXMHIYUAAAAJ&amp;hl=en" target="_blank" rel="noopener">Google Scholar</a>, the contents are freely available in electronic version. JGSM is published quarterly in February, May, August, and November.</p> <p><a title="issn" href="http://issn.pdii.lipi.go.id/issn.cgi?daftar&amp;1402376294&amp;1&amp;&amp;" target="_blank" rel="noopener"><strong>ISSN : 0853-9634 (print)</strong></a></p> <p><a title="eissn" href="http://issn.pdii.lipi.go.id/issn.cgi?daftar&amp;1485227549&amp;1&amp;&amp;" target="_blank" rel="noopener"><strong>e-ISSN : 2549-4759 (online)</strong></a></p> <p><strong><em><strong>DOI Prefix: </strong></em><a title="JGSM" href="https://doi.org/10.33332">https://doi.org/10.33332</a><br /></strong></p> Pusat Survei Geologi en-US Jurnal Geologi dan Sumberdaya Mineral 0853-9634 <p>Authors who publish articles in <strong>Jurnal Geologi dan Sumberdaya Mineral (JGSM.Geologi)</strong> agree to the following terms:</p><ol><li>Authors retain copyright of the article and grant the journal right of first publication with the work simultaneously licensed under a <strong>CC-BY-NC</strong> or <strong>The Creative Commons Attribution–ShareAlike License.</strong></li><li>Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in this journal.</li><li>Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See <a href="http://opcit.eprints.org/oacitation-biblio.html" target="_blank">The Effect of Open Access</a>)</li></ol> https://jgsm.geologi.esdm.go.id/index.php/JGSM/article/view/806 <p>Dua buah rembesan minyak bumi diambil dari daerah Torete, Morowali, Provinsi Sulawesi Tengah. Kedua sampel rembesan telah dilakukan analisis GC (gas chromatography) dan GCMS (gas chromatography and mass spectometry). Analisis geokimia biomarker dilakukan untuk mengetahui karakter minyak bumi berupa asal material organik, lingkungan pengendapan, dan tingkat kematangan. Pada kromatogram alkana normal, kedua sampel menunjukkan satu puncak (unimodal) sebelum nC20 dengan rasio Pr/Ph 0,87 dan 0,92. Fragmentogram m/z 217 menunjukkan sedikit dominasi pada sterana C29 dibanding sterana C27 dan sedikit kehadiran dari diasterana. Fragmentogram m/z 191 menunjukkan adanya dominasi pada terpana trisiklik C23 dan terpana tetrasiklik C24 serta kehadiran terpana trisiklik C26+. Pada terpana pentasiklik menunjukkan dominasi Tm terhadap Ts, hopana C29 terhadap hopana C30, kehadiran seri norhopana C30 dan gamaserana, serta homohopana C35 yang sedikit lebih tinggi dari homohopana C34. Biomarker petunjuk tumbuhan tinggi (oleanana dan bikadinana) tidak hadir pada kedua sampel. Hal ini menunjukkan bahwa kedua sampel minyak bumi berasal dari batuan induk karbonat dengan material organik alga, plankton, radiolaria, atau diatom lingkungan pengendapan anoksik-suboksik (lingkungan transisional), dan tingkat kematangan awal matang sampai level matang.</p> <p>Katakunci: biomarker, GC, GCMS, Torete, Morowali, Sulawesi Tengah.</p> Achmad Fahruddin Eddy Ariyono Subroto Very Susanto Lauti Dwita Santy Ryandi Adlan Copyright (c) 2024 Achmad Fahruddin, Eddy Ariyono Subroto, Very Susanto, Lauti Dwita Santy, Ryandi Adlan http://creativecommons.org/licenses/by-nc/4.0 2024-11-04 2024-11-04 25 4 205 216 10.33332/jgsm.geologi.v25i4.806 https://jgsm.geologi.esdm.go.id/index.php/JGSM/article/view/827 <p>Kendal Area in Central Java experiences rapid regional geology development. A wide flat area extending towards the Pantura, approximately 40 km wide and 20 km long, is influenced by the Bodri River. The Kendal basin formation is driven by Java’s regional compression tectonics. Major faults show the east-west direction as thrust faults and northeast-southwest direction as strike slip faults correspond to Java’s Regional Structures. Active and passive satellite imagery reveals geomorphic features such as deltas, coastal deposits, paleochannels, break slopes as faults zone, and topographic offsets of the area. The drainage pattern varies with deposit types: distributary channels in the north, meandering channels in the middle, and tributary channels in the south. Fusion image of Landsat 8 and National Digital Elevation Model (DEMNAS) produced by Badan Informasi Geospasial Indonesia (BIG) highlight distinct topographical boundaries and slopes. Residual gravity data shows subsurface contrasts, indicating dominant directions related to surface faults. Other supporting data used include magnetic anomaly imagery processed using the Reduce to Pole (RTP) method which are used to position the source of magnetic anomalies directly above their actual subsurface location. The RTP results enable more accurate interpretation of the distribution and depth of subsurface magnetic sources. The magnetic RTP model aligns with imagery, exhibiting east-west, northeast-southwest, and northwest-southeast trends. This structural interpretation is substantiated by field validation, with evidence of fault cliffs, lithologic offset, fault planes, mylonitization, and fault breccias corroborating the findings.</p> <p>Keywords: Bodri River, gravity, Kendal, landsat 8, Java’s regional structures, magnetic anomaly. </p> Jamal Jamal Indra Sanjaya Dian Hari Saputro Aji Suteja Copyright (c) 2024 Jamal Jamal, Indra Sanjaya, Dian Hari Saputro, Aji Suteja http://creativecommons.org/licenses/by-nc/4.0 2024-11-08 2024-11-08 25 4 217 223 10.33332/jgsm.geologi.v25i4.827