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All Journal Al-Fiziya: Journal of Materials Science, Geophysics, Instrumentation and Theoretical Physics JURNAL FISIKA JOURNAL ONLINE OF PHYSICS JPSE (Journal of Physical Science and Engineering) Journal of Physics and Its Applications JURNAL EKSAKTA PENDIDIKAN (JEP) KONSTAN - JURNAL FISIKA DAN PENDIDIKAN FISIKA JURNAL PENDIDIKAN TAMBUSAI GERVASI: Jurnal Pengabdian kepada Masyarakat Kappa Journal Inovasi Pendidikan: Jurnal Pendidikan Gravitasi: Jurnal Pendidikan Fisika dan Sains Jurnal ABDINUS : Jurnal Pengabdian Nusantara Jurnal Fisika dan Terapannya PAKAR Pendidikan Jurnal Pendidikan, Sains, Geologi, dan Geofisika (GeoScienceEd Journal) Pillar of Physics Education : Jurnal Berkala Ilmiah Pendidikan Fisika Pillar of Physics: Jurnal Berkala Ilmiah Fisika JRFES Journal of Climate Change Society Jurnal Lingkungan Almuslim Uranus: Jurnal Ilmiah Teknik Elektro, Sains dan Informatika Journal of Experimental and Applied Physics
Letmi Dwiridal
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Agriculture, Biological Sciences & Forestry Humanities Astronomy Biochemistry, Genetics & Molecular Biology Chemistry Computer Science & IT Control & Systems Engineering Earth & Planetary Sciences Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Environmental Science Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Library & Information Science Materials Science & Nanotechnology Mathematics Physics Social Sciences Other

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Identifikasi Struktur Bawah Permukaan Gunung Merapi di Kabupaten Magelang Menggunakan Metode Geomagnetik Melalui Pemodelan Inversi 3D Denandra, Alza; Amir, Harman; Dwiridal, Letmi; Zulhendra, Zulhendra
Jurnal Pendidikan Tambusai Vol. 9 No. 2 (2025): Agustus
Publisher : LPPM Universitas Pahlawan Tuanku Tambusai, Riau, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/jptam.v9i2.30891

Abstract

Kabupaten Magelang merupakan wilayah dataran tinggi yang berada di zona vulkanik aktif Gunung Merapi, dengan litologi dominan berupa batuan vulkanik muda hasil aktivitas Kuarter. Penelitian ini bertujuan mengidentifikasi struktur bawah permukaan wilayah Gunung Merapi di Kabupaten Magelang menggunakan metode geomagnetik berbasis data EMAG2 dan pemodelan inversi 3D. Hasil analisis menunjukkan variasi nilai suseptibilitas magnetik berkisar antara -40 hingga >60 SI, yang merepresentasikan perbedaan litologi bawah permukaan, seperti lava segar, intrusi beku, batuan alterasi, dan zona rekahan. Visualisasi 3D menunjukkan distribusi anomali magnetik yang mengikuti arah struktur geologi, termasuk sesar aktif seperti Sesar Opak. Model 3D pada tiga lintasan memperlihatkan akumulasi batuan vulkanik dan tubuh intrusi yang signifikan pada kedalaman 1–4 meter. Temuan ini menunjukkan bahwa metode geomagnetik efektif dalam mengungkap struktur bawah permukaan dan memiliki nilai strategis dalam upaya mitigasi bencana di kawasan rawan letusan Gunung Merapi.
Identifikasi Struktur Bawah Permukaan Gunung Argopuro Kabupaten Probolinggo Menggunakan Metode Geomagnetik Melalui Pemodelan Inversi 3D Saqilah, Alya; Amir, Harman; Dwiridal, Letmi; Zulhendra, Zulhendra
Jurnal Pendidikan Tambusai Vol. 9 No. 2 (2025): Agustus
Publisher : LPPM Universitas Pahlawan Tuanku Tambusai, Riau, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/jptam.v9i2.30893

Abstract

Penelitian ini bertujuan mengidentifikasi struktur bawah permukaan Gunung Argopuro, Kabupaten Probolinggo, menggunakan data geomagnetik EMAG2 melalui pemodelan inversi 3D. Data dianalisis dengan metode Reduce to Pole (RTP), menghasilkan anomali magnetik antara -2600 nT hingga +5800 nT. Hasil pemodelan mengungkap keberadaan tubuh batuan non-magnetik (pluton/batolit) pada kedalaman >4 km dengan suseptibilitas sangat rendah (<0.0012 SI), yang diduga sebagai sisa dapur magma purba. Selain itu, terdeteksi zona intrusi batuan beku segar pada kedalaman 2–5 km dengan suseptibilitas menengah-tinggi (0.0013–0.0015 SI), berasosiasi dengan andesit Gunung Argopuro (Qva). Temuan ini menunjukkan sistem magmatik kompleks dengan pola dome dan kaldera purba, penting untuk pemahaman geologi regional, mitigasi bencana, dan eksplorasi sumber daya. Kata kunci: Gunung Argopuro, Geomagnetik, Inversi 3D, Suseptibilitas, Struktur Bawah Permukaan.
Penentuan Kedalaman Titik Curie Berdasarkan Data Geomagnetik dengan Menggunakan Analisis Spektral dan Upward Continuation Zikri, Ahmad Raihan; Amir, Harman; Dwiridal, Letmi; Zulhendra, Zulhendra
Jurnal Pendidikan Tambusai Vol. 9 No. 2 (2025): Agustus
Publisher : LPPM Universitas Pahlawan Tuanku Tambusai, Riau, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/jptam.v9i2.30915

Abstract

Penelitian ini bertujuan untuk menentukan kedalaman titik Curie di wilayah Kabupaten Magelang, Jawa Tengah, dengan menggunakan metode analisis spektral dan upward continuation berbasis data geomagnetik. Kedalaman titik Curie merupakan parameter penting dalam mengidentifikasi potensi panas bumi, karena berkaitan dengan distribusi panas di bawah permukaan bumi. Data yang digunakan berupa anomali medan magnet total dari satelit Thematic Mapper EMAG2 v3 dengan resolusi 2 arc- minute. Analisis spektral dilakukan untuk memperoleh kedalaman atas, kedalaman pusat, dan kedalaman titik Curie pada tiap blok, sedangkan teknik upward continuation digunakan untuk memisahkan komponen regional dan residual pada anomali magnetik. Hasil penelitian menunjukkan bahwa kedalaman titik Curie di wilayah studi berkisar antara 30 km hingga >140 km, dengan rata-rata 67,96 km. Wilayah tengah hingga timur laut seperti Kecamatan Mertoyudan, Bandongan, dan Secang memiliki kedalaman yang relatif dangkal dan gradien geotermal tinggi, yang mengindikasikan potensi panas bumi sedang hingga tinggi. Sebaliknya, bagian barat dan barat daya menunjukkan kedalaman lebih besar dan gradien rendah. Dengan demikian, kombinasi metode yang digunakan terbukti efektif dalam mengidentifikasi zona prospektif panas bumi berdasarkan distribusi kedalaman titik Curie.
Analysis Of Seismic Quiescence Precursors Before The M7.4 Earthquake Of 28 September 2018 In Central Sulawesi Based On Seismotectonic Spatial Distribution And Earthquake Fracture Lengths zu, Zurahma; Syafriani; Dwiridal, Letmi; Zulhendra, Zulhendra
Jurnal Pendidikan, Sains, Geologi, dan Geofisika (GeoScienceEd Journal) Vol. 6 No. 1 (2025): Februari
Publisher : Mataram University

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The Central Sulawesi earthquake with coordinates 2°30‘S -1°50’ N and 119°0'-124°20 E magnitude 7.4 in Palu, Donggala Regency on 28 September 2018. This earthquake was a significant and destructive earthquake in Central Sulawesi. A significant earthquake is preceded by a seismic quiescence. The aim of the study was to determine when the seismic quiescence occurred and seismic activity after the earthquake alongside fracture length. The method of analysis of seismic quiescence and fracture length is z-value and Wells and Coppersmith equation. Data processed with MATLAB and Zmap were 1478 events from 1983-2023. The study area is divided into several grids with sizes of 0.1°* 0.1°. The number of earthquakes included (N = 800, 700, 600, 500, 400, 300, and 200). The z-value was calculated for each grid based on the earthquake data organized in one grid and seismic activity after earthquake. The results of the analysis of the z-value calculation in each grid show of seismic quiescence before a significant earthquake. Based on the results of the spatial distribution of z-value in Central Sulawesi, the seismic quiescence preceded the 28 September 2018 earthquake event (M 7.4) by about 21 years beginning in 1990. When cut at 2019.6, there was a decrease in seismic activity again, which indicated that an earthquake would occur, so it was thought to be a trigger factor for future earthquake precursors. While the fracture length of the 7.4 Mw earthquake of 104,232 meters shows a positive correlation between magnitude and fracture length.
Analysis of Seismicity and Return Period of Earthquakes in South Pesisir Regency West Sumatra Province Using the Likelihood Method Husna, Azmi Asmaul; Syafriani; Hamdi; Letmi Dwiridal
Jurnal Pendidikan, Sains, Geologi, dan Geofisika (GeoScienceEd Journal) Vol. 6 No. 1 (2025): Februari
Publisher : Mataram University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/goescienceed.v6i1.589

Abstract

The South Pesisir area was one of the areas that was rocked by an earthquake on September 30, 2009. The earthquake that occurred caused damage and loss of life. Based on these conditions, the South Pesisir Regency area was identified as an earthquake-prone area. Therefore, it is necessary to research seismicity and return period in the regency. This research used the statistical likelihood method to determine the accumulated rock stress, seismcity and return period of eartquakes. The data used is earthquake data for the period 1934-2023 with a magnitude ≥4 SR and a depth of ≤300 km. The results of this research provided an overview of the seismicity and return period in the South Pesisir Regency. Seismicity was determined based on rock stress condition (b-value) and on the level seismic activity (a-value). Based on calculations showed that the a-value and b-value for the 20-year and 90-year intervals ranged between 6.16-10.9 and 0.953-2.17, respectively. Earthquakes return periods at intervals of 20 years and 90 years for the magnitude range 4.0-4.4 produced almost the same return period, namely less than one year. Meanwhile, earthquakes with magnitudes of 4.5-6 had recurrence periods ranging from 1 to 63 years.
Seismic Vulnerability Index Analysis In The Sub-District Of Lake Kembar, Solok Regency, As An Effort To Determine The Potential Aslided Area Using HVSR Method Percindira, Ella Dwi; Syafriani, Syafriani; Hamdi, Hamdi; Dwiridal, Letmi
Journal of Experimental and Applied Physics Vol 1 No 1 (2023): June Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v1i1.6

Abstract

Nagari Kampung Batu Dalam, Danau Kembar District, experienced a landslide caused by high rainfall and steep topography (slope). However, there needs to be more information regarding the classification of landslide potential levels that will occur. So it is essential to carry out this study to determine the soil type, sediment depth, and seismic vulnerability index. Ten microtremor data are scattered in this area. Measurements are carried out using an MAE Sysmatrack and 3D Seismic Surface Sensor, and this is done because these measurements are not difficult to carry out and do not require a large amount of money. However, there is an abundance of information that can be analyzed. Microtremor signal data were processed using Geopsy software with the Horizontal to Vertical Spatial Ratio (HVSR) method and soil profiles which stated the parameters of the shear wave velocity (Vs) and the depth of the sediment layer (H) using the ellipticity curve method. The results obtained show that the f0 value ranges from 0.6-4.37 Hz, the Amplification Factor ranges from 1.4-17.1, the sediment thickness (H) ranges from 24.5-240.8 m, and the seismic susceptibility index ranges from 1.72E-04 - 3.21E-02 cm/s2. Based on the mapping and modeling, it shows that alluvial rocks dominate the locations that have the potential for landslides.
Earthquake Intensity Determination Based on Maximum Land Acceleration in Padang City Area Using Atkinson Boore Method (2003) Linda Susanti; Syafriani, Syafriani; Hamdi, Hamdi; Dwiridal, Letmi
Journal of Experimental and Applied Physics Vol 2 No 1 (2024): March Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v2i1.40

Abstract

Geologically, the city of Padang had the potential for large earthquake impacts due to its location within the Sumatran Fault, Mentawai Fault, and above the Subduction Zone. The magnitude of earthquake damage was determined by soil quality factors and earthquake intensity. To determine the extent of damage, the maximum ground acceleration value was used. This value represented the maximum ground vibration acceleration that occurred at a specific location within a particular area, resulting from all earthquakes that occurred during a specific time period. The maximum ground acceleration value and earthquake intensity in the Padang City area could be calculated using the Atkhinson Boore (2003) method. This study was a quantitative research that commenced by examining relevant theories related to the issue at hand. The research then proceeded with the collection of secondary data obtained from the United States Geological Survey (USGS) website. Specifically, earthquake data for the period between 2000 - 2020 in the Padang City area with coordinates LS- LS and BT- BT, and a magnitude M ≥ 5.0 SR depth < 100 km were utilized. Historical earthquake data was employed to determine earthquake intensity values, which were then used to assess the earthquake risk in the Padang City area. Based on the calculation results, the maximum acceleration value of soil was found between 0.519001 g- 0.603847 g. The highest value of maximum acceleration of soil was located in Bungus Teluk Kabung area, while the lowest value was found in Koto Tangah area. The distribution of earthquake intensity (MMI) in Kota Padang area has a value of VIII MMI.
Seismotectonic Analysis and Seismic Potensial of The Sumatra Region Using The Guttenberg-Richter Method Yusrila, Yoga; Syafriani, Syafriani; Hamdi, Hamdi; Dwiridal, Letmi
Journal of Experimental and Applied Physics Vol 2 No 1 (2024): March Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v2i1.46

Abstract

Sumatera is one of the most seismically active regions in Indonesia. This is due to the presence of subduction zones and active faults that influence the plate tectonic activity of the region, resulting in many earthquake events that cause damage and loss. One of the efforts to mitigate earthquake disasters is the analysis of seismotectonic parameters, which are indicated by the a-value and b-value of the Gutenberg-Richter equation in the earthquake frequency-magnitude relationship. Low seismotectonic parameters (a-value) and (b-value) can be interpreted as low seismic activity and high local rock stress conditions, and vice versa high (a-value) and (b- value). In this study, the analysis was performed spatially and temporally from the National Earthquake Information Center United States Geological Survey (NEISUSGS) earthquake catalogue. The data obtained in the form of longitude, latitude, depth, magnitude, time and location of the earthquake event, the data are limited to M ≥ 4.0Mw and Depth ≤ 350KM in the Sumatera region with the boundaries of 6030'LU-6°30'LS and 94BT-106°BT for the period 1990-2022. Based on the estimation results of the Guttenberg-Richter method in ZMAP v6 software, the b-value is 0.92-1.04 and the a-value is 7.42-7.97, with a return period of 6.5 Mw earthquakes generally ranging from 5-25 years.
Consistency of Magnetic Susceptibility Values in Raw Mix 2 using Bartington Magnetic Susceptibility Meter Sensor Type B Kolotosa, Julio Fadjar; Hamdi, Hamdi; Mufit, Fatni; Dwiridal, Letmi
Journal of Experimental and Applied Physics Vol 2 No 2 (2024): June Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v2i2.52

Abstract

The process of making cement goes through quite long stages, one of the processes is grinding at the Raw Mill. Raw Mill is divided into two large groups, Horizontal Mill and Vertical Mill, in Horizontal Factory. The milling result at the Horizontal Mill is Raw Mix 2 and quality testing will be carried out. In quality testing, testing is usually carried out on chemical parameters and there is no testing based on physical parameters. By looking for the magnetic susceptibility score of raw cement samples in Raw Mix 2 using the Bartington Magnetic Susceptibility Meter Type B sensor, you can see the consistency of magnetic minerals in raw cement in Raw Mix 2. Samples were taken from the Padang Semen Factory every hour of every day from February 1 to February 10, 2022, the samples were then measured using the Bartington Magnetic Susceptibility Meter Type B Sensor. The measurement results showed that the magnetic susceptibility value of Raw Mix 2 ranged from 79.8 x/kg to 206.9 x/kg, and standard deviation calculations were used. The data is interpreted into a graph and it shown that the magnetic susceptibility value of Raw Mix 2 obtained can be said to be consistent and of good quality. The magnetic properties of Raw Mix 2 obtained according on the magnetic susceptibility score obtained are antiferromagnetic. The grain type in Raw Mix 2 was found to have almost no superparamagnetic grains or contained less than 10% superparamagnetic grains.
Microzonation of Seismic Vulnerability In Padang Panjang Timur Sub-District, Padang Panjang City Based on Microtremor Measurement Elizha, Zellvia; Syafriani, Syafriani; Hamdi, Hamdi; Dwiridal, Letmi
Journal of Experimental and Applied Physics Vol 2 No 3 (2024): September Edition
Publisher : Department of Physics, Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jeap.v2i3.70

Abstract

Padang Panjang City is one of the cities in West Sumatra which has a high level of risk of the natural phenomenon of earthquakes. This is due to the fact that it is traversed by the active Sumatran fault which can cause earthquakes at any time. The purpose of this study was to determine the value of the seismic vulnerability index in Padang Panjang Timur District, Padang Panjang City using microtremor measurements. This type of research is descriptive research, namely research that describes the symptoms or phenomena studied. The location for data collection was Padang Panjang Timur District, Padang Panjang City, West Sumatra Province. There are 15 data collection points, and the distance between points is 500 m. The microtremor method of measuring this microtremor can determine the dominant frequency value (f0), amplification factor (A0), and susceptibility index value (Kg). Microtremor data processing was used to obtain the H/V curve at each point of data collection using Geopsy software. The results of the microzonation of the seismic susceptibility index (Kg) ranged from 1.05 × 10-6 s²/cm to 170.09 × 10-6 s²/cm. High seismic vulnerability index values ​​are found in the Koto Panjang Sub-District, Tanah Pak Lambik Sub-District, Guguk Malintang Sub-District, Ngalau Sub-District and Ganting Sub-District.
Co-Authors - Hamdi AA Sudharmawan, AA Aditio, Rama Ahmad Fajrin Ahmad Fauzi Akmam Akmam Akmam Amali Putra Amirullah, Fajar Fikri Andini, Ulvia Sepra Andriani, Welli Annisa Rahma Jelita Asrizal Delima Putri Denandra, Alza Dhea Fitria Elizha, Zellvia Emiliannur Emiliannur Emriska, Vellya Ramadhani Fadhila Ulfa Jhora Farras Drasih, Nabilah Fatni Mufit Fauzi Ahmad Muda Festiyed Florentina Simalango, Nora Fortuna, Aprilla Fuja Novitra Gusnedi Gusnedi Hamdi Hamdi Hamdi Hamdi Hamdi Hamdi Rifai Handayani, Silvia Sri Harman Amir hidayanti, hidayanti Hidayati Hidayati Hidayati Hidayati Hufri Hufri Husna, Azmi Asmaul Ikram, Riziqul Kiroomin Barorotin Muji Kolotosa, Julio Fadjar lara agustia Linda Susanti Madinah, Nur Mahrizal Mahrizal Maidani, Delvi Putri Marlina Alimir Mesi, Mesi Mia Cahyanti Muhammad Hafiz Murtiani Murtiani Mutiara Novichri, Viona Nengsih, Reni Fitria Nofi Yendri Sudiar Nur Azizah Percindira, Ella Dwi Putri Dwi Sari Putri Dwi Sundari Putri, Ulfa Haldiani Putri, Zakiah Putri Rahmat Hidayat Rahmy Novia Ratnawulan . Renol Afrizon Resa, Jerrifel Rata Resi Silvianis Resti Sundari rina, rina novita Salsabila, Salsabila Saqilah, Alya Sari, Nurul Fadillah Silvi Yulia Sari Siska Fitri Alwi Sri Ayu Wahyuni Sudiar, Novi Yendri Syafriani Syafriani Syafriani Syafriani Syafriani, Syafriani Syafriani, - Ulfa Jhora, Fadhila Wahyu Ramadhan Wahyuni Satria Dewi Wulandari, Mia Yana Ramadhani Yendri Sudiar, Nofi Yurnetti Yurnetti Yusrila, Yoga Yusrizal Yusrizal Zainul Adha Zatil Ismah, Amirah Zikri, Ahmad Raihan zu, Zurahma Zulhendra Zulhendra