Identifikasi Struktur Geologi dan Petrografi di sekitar Observatorium Astronomi Lampung Gunung Betung

  • Hendra Saputra Teknik Geologi, Institut Teknologi Sumatera, Lampung Selatan, Indonesia 35365
  • Luhut P. Siringorongo Teknik Geologi, Institut Teknologi Sumatera, Lampung Selatan, Indonesia 35365
  • Cahli Suhendi Teknik Geofisika, Institut Teknologi Sumatera, Lampung Selatan, Indonesia 35365
  • Lea Kristi Agustina Teknik Geomatika, Institut Teknologi Sumatera, Lampung Selatan, Indonesia 35365

Abstract

Lampung Astronomical Observatory (LAO) is located on Betung Mountain which is quite close to the Semangko active fault zone. Betung Mountain is part of the Bukit Barisan which is located west of the city of Bandar Lampung. This mountain has an altitude of about 1200 meters above sea level. There are 6 interesting stations. Most of the stations are located on the upper slopes of Betung Mountain. In the Talang Aji area, there are 2 springs. The other 4 stations consist of waterfalls with varying heights: Talang Teluk waterfall (30 m), Talang Rabun waterfall (20 m), Betung waterfall consists of two minor terraced waterfalls with a height of 5 and 10 m respectively, and Kubu Jambu waterfall (12 m). In general, the orientation of the faults of Mt. Betung was northeast-southwest. The faults are also associated with several waterfalls found in the field. From the joint data processing, it can be interpreted that the fault formed on Betung Mountain is normal. The lithology of Betung Mountain is dominated by volcanic deposits in the form of tuffs. In certain rivers, there are outcrops of lava igneous rock in the form of Andesites. Andesite lava in the northern and southern parts of Betung Mountain has different characteristics.

Downloads

Download data is not yet available.

References

[1] T. Fitch, “Plate convergence, transcurrent faults, and internal deformation adjacent to southeast Asia and the western Pacific,” J. Geophys. Res., vol. 77, no. 23, pp. 4432–4460, 1972.
[2] R. McCaffrey, “Slip vectors and stretching of the Sumatran fore arc,” Geology, vol. 19, no. 9, pp. 881–884, 1991, doi: 10.1130/0091-7613(1991)019<0881:SVASOT>2.3.CO;2.
[3] K. Sieh and D. Natawidjaja, “Neotectonics of the Sumatran fault, Indonesia,” J. Geophys. Res. Solid Earth, vol. 105, no. B12, pp. 28295–28326, 2000, doi: 10.1029/2000jb900120.
[4] D. H. Natawidjaja et al., “Source parameters of the great Sumatran megathrust earthquakes of 1797 and 1833 inferred from coral microatolls,” J. Geophys. Res. Solid Earth, vol. 111, no. 6, pp. 1–37, 2006, doi: 10.1029/2005JB004025.
[5] Travis and B. Russell, Classification of Rocks, Colorado. USA: Quarterly of the Colorado School of Mines, 1955.
[6] S. S. Nalbant, S. Steacy, K. Sieh, D. Natawidjaja, and J. McCloskey, “Seismology: Earthquake risk on the Sunda trench,” Nature, vol. 435, no. 7043, pp. 756–757, 2005, doi: 10.1038/nature435756a.
[7] K. Sieh et al., “Earthquake supercycles inferred from sea-level changes recorded in the corals of west Sumatra,” Science (80-. )., vol. 322, no. 5908, pp. 1674–1678, 2008, doi: 10.1126/science.1163589.
[8] O. Bellier et al., “Paleoseismicity and seismic hazard along the Great Sumatran fault (Indonesia),” J. Geodyn., vol. 24, no. 1–4, pp. 169–183, 1997, doi: 10.1016/s0264-3707(96)00051-8.
[9] J. A. Katili and F. Hehuwat, “On the occurrence of large transcurrent faults in Sumatra, Indonesia,” J. Geosci., vol. 10, 1967.
[10] D. H. Natawidjaja, K. Sieh, S. Ward, R. Edwards, B. Suwargadi, and J. Galetzka, Large active faults along the Sumatran plate margin and their seismic threat to Indonesia, Malaysia and Singapore. Yogyakarta: Geosea-Indonesian Association of Geologist, 2001.
[11] A. Mangga, Amirudin, T. Suwarti, S. Gafoer, and Sidarto, Geologi of Tanjungkarang quadrangle, Sumatra. Bandung: Geological Research and Development Centre, 1994.
Published
2020-12-20
How to Cite
SAPUTRA, Hendra et al. Identifikasi Struktur Geologi dan Petrografi di sekitar Observatorium Astronomi Lampung Gunung Betung. Journal of Science and Applicative Technology, [S.l.], v. 4, n. 2, p. 91-98, dec. 2020. ISSN 2581-0545. Available at: <https://journal.itera.ac.id/index.php/jsat/article/view/265>. Date accessed: 23 jan. 2021. doi: https://doi.org/10.35472/jsat.v4i2.265.