KARAKTERISTIK BASAL DAERAH TANJUNG AGUNG
DOI:
https://doi.org/10.34151/prosidingsnast.v1i1.4161Keywords:
basalt, characteristics, columnar joint, petrographyAbstract
Research on crystalline rocks in Lampung has been carried out by various researchers, but this research still does not cover other areas, such as Tanjung Agung village, Katibung District, South Lampung. Therefore, this research aims to analyze the characteristics of basalt rocks in the Tanjung Agung area, South Lampung, which is important for expanding understanding of the geological diversity in the region. These rocks are found in the form of entablature-type columns formed from basalt lava flows. The methods used include literature studies, field observations, and laboratory analysis, especially petrographic analysis, to identify mineral content and rock structure to understand the crystallization process and formation of columnar joints. The results of the petrographic analysis show a porphyritic texture with plagioclase, pyroxene, and hornblende phenocrysts, as well as a finer groundmass. These rocks show gradual crystallization and textural variations such as trachytic, sieve, glomeroporphyritic, and zoning, which reflect processes of decompression, pressure reduction, and magma mixing. Based on the mineral composition, this rock is classified as basalt which undergoes a gradual crystallization process, namely the formation of large crystals (phenocrysts) at depth and the formation of a finer groundmass at the surface. This research also opens up opportunities for geochemical analysis to understand the origin and evolution of magma in the region. Thus, this research provides further insight into the dynamics of magmatism and rock formation in the Tanjung Agung area.
References
Imaniar, N., Patonah, A., & Prambada, O. (2021). Karakteristik Batuan Vulkanik Daerah Cisanggarung dan Sekitarnya, Kecamatan Cimenyan, Kabupaten Bandung, Jawa Barat. Padjadjaran Geoscience Journal, 5(5), 492–497.
Natalia Sharlota Kuhuela, Miftahussalam, D. I. P. (2021). Karakteristik Columnar Joint Pada Lava Andesit Berdasarkan Analisis Petrografi Desa Tumpuk, Kecamatan Pule Kabupaten Trenggalek Provinsi Jawa Timur. Jurnal Teknomineral, 3(2), 90–97.
Pranata, M. B., Marin, J., & Aribowo, Y. (2018). Petrogenesis Batuan Beku dan Karakteristik Kekar Tiang di Bukit Pajangan, Desa Sidomulyo, Kecamatan Purworejo, Kabupaten Purworejo, Jawa Tengah. Jurnal Geosains Dan Teknologi, 1(2), 41. https://doi.org/10.14710/jgt.1.2.2018.41-49
Renjith, M. L. (2014). Micro-textures in plagioclase from 1994-1995 eruption, Barren Island Volcano: Evidence of dynamic magma plumbing system in the Andaman subduction zone. Geoscience Frontiers, 5(1), 113–126. https://doi.org/10.1016/j.gsf.2013.03.006
Rosyada, K., Rosana, M. F., Subagja, A., & F, K. A. (2019). Karakteristik Petrografi Lava Siantu Daerah Sijuk Pulau Belitung. Padjajaran Geoscience Journal, 3(5), 343–353.
Syafri, I., Sudradjat, A., Sulaksana, N., & Hartono, G. (2010). The Evolution of Gajahmungkur Paleovolcano, Wonogiri, Central Java, as A Reference to Revize the Terminology of “Old Andesite Formation.” Indonesian Journal on Geoscience, 5(4). https://doi.org/10.17014/ijog.v5i4.109
Widiatama, A. J., & Hendrawan, R. N. (2022). Reintepretation of Lampung Cretaceous-Paleogene Granitoids Genesis and Its Tectonic Implications. Jurnal Geocelebes, 6(2), 135–144. https://doi.org/10.20956/geocelebes.v6i2.19633
Widiatama, A. J., Santy, L. D., Natalia, H. C., Wahyudiono, J., & Ikhram, R. (2021). Karakteristik Geokimia Basal Alkali Formasi Manamas di Sungai Bihati, Baun, Pulau Timor. Eksplorium, 42(1), 1. https://doi.org/10.17146/eksplorium.2021.42.1.6205
Zaenudin, A., Aribowo, Y., Kusumastuti, D. I., & Martin, Y. (2016). Pemetaan Geologi Dan Uji Sifat Fisika Batuan Andesit Di Bakauheni Dan Tanjungan, Lampung. Prosiding Seminar Nasional Avoer 8, 31–41.
Downloads
Published
Issue
Section
License
Copyright (c) 2024 Learning Halawa, Desy Hartati, Ilham Putra Yusti
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
