ANALISIS TENSOR FASE DAN PEMODELAN 2D DATA MAGNETOTELURIK GABBS VALLEY, NEVADA, USA

Authors

  • Pahri Pahri Program Studi Teknik Geofisika, Institut Teknologi Sumatera
  • Andri Yadi Paembonan Program Studi Teknik Geofisika, Institut Teknologi Sumatera
  • Selvi Misnia Irawati Program Studi Teknik Geofisika, Institut Teknologi Sumatera

DOI:

https://doi.org/10.23960/jge.v9i3.301

Keywords:

2D Inversion, Geothermal Exploration, Magnetotelluric, Phase Tensor

Abstract

Metode magnetotellurik (MT) merupakan salah satu teknik dalam metode geofisika yang menggunakan sumber alami dalam bentuk medan elektromagnetik yang berasal dari medan listrik dan variasi medan magnet di bumi. Dalam proses interpretasi kondisi bawah permukaan bumi, data MT masih dipengaruhi oleh noise atau distorsi yang akan menutupi dimensionalitas sebenarnya. Oleh karena itu dilakukan analisis tensor fase untuk menentukan dimensionalitas dan arah geoelectrical strike guna mengidentifikasi struktur bawah permukaan yang tidak dipengaruhi oleh distorsi galvanic. Berdasarkan hasil yang diperoleh, daerah penelitian memiliki dimensionalitas 2D dengan orientasi barat laut – tenggara dengan arah N345 E. Hasil inversi 2D menunjukkan bahwa nilai resistivitas < 10  diidentifikasi sebagai zona alterasi atau clay cap yang didominasi oleh mineral smektit. Nilai resistivitas 20 – 250  diidentifikasi sebagai reservoar yang bersifat permeabel yang tersusun atas batu pasir kasar, kerikil, basal, andesit, riolit, riodasit tuff dan konglomerat. Lapisan dengan nilai resistivitas > 250  diidentifikasi sebagai Upper Triassic Metasediment yang mengalami sedimentasi yang sangat keras, hal tersebut disebabkan tekanan dan suhu tinggi. Lapisan ini tersusun atas meta batu lanau, batu lempung, meta batu pasir, dan meta konglomerat.

Author Biography

Selvi Misnia Irawati, Program Studi Teknik Geofisika, Institut Teknologi Sumatera

Lecturer Geophysical Engineering Institut Teknologi Sumatera

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Published

2023-11-29

How to Cite

Pahri, P., Paembonan, A. Y., & Irawati, S. M. (2023). ANALISIS TENSOR FASE DAN PEMODELAN 2D DATA MAGNETOTELURIK GABBS VALLEY, NEVADA, USA. JGE (Jurnal Geofisika Eksplorasi), 9(3), 206–216. https://doi.org/10.23960/jge.v9i3.301

Issue

Vol. 9 No. 3 (2023)

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