PENENTUAN STRATIGRAFI KECEPATAN GELOMBANG GESER (VS) DI DAERAH RAWAN ABRASI KABUPATEN BENGKULU UTARA MENGGUNAKAN METODE MULTICHANNEL ANALYSIS OF SURFACE WAVE (MASW)

  • Refrizon Refrizon
  • Nanang Sugianto
  • Admo Bernard
Keywords: stratigraphy, shear wave, MASW, abrasion

Abstract

Weak subsurface rock structures are thought to be one of the factors causing high abrasion rates in North Bengkulu Regency. This subsurface rock structure is estimated based on the analysis of shear wave velocity (Vs) from the measurement of Multichannel Analysis of Surface Wave (MASW) at 20 points along the coastline. Vs values ​​are interpreted in the form of 1D and 2D profiles to illustrate the structure and type of constituent material in each depth and layer. The results of the analysis show that the stratigraphy of the subsurface Vs value in abrasion-prone areas of North Bengkulu consists of three layers of rock. The first layer with a value of Vs<180 m/s indicated to be dominated by soft clay, the second layer 180<Vs<360 m/s was dominated by rigid soil and the third layer 360<Vs<760 m/s indicated dominated by very dense soil and soft rock. Composition of rocks consists of deposits of sand, gravel, clay, and alluvium which have a low density and vary in each depth. There were no indications of hard rock to a depth of 30 meters, only soft-structured rocks that were very easily cracked and brittle. These results indicate that the subsurface rock structure in the abrasion-prone areas of North Bengkulu is a weak structural rock that is susceptible to deformation such as crack, settlement, and collapse like the abrasion phenomenon that has occurred so far.

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Published
2019-09-13
How to Cite
Refrizon, R., Sugianto, N., & Bernard, A. (2019, September 13). PENENTUAN STRATIGRAFI KECEPATAN GELOMBANG GESER (VS) DI DAERAH RAWAN ABRASI KABUPATEN BENGKULU UTARA MENGGUNAKAN METODE MULTICHANNEL ANALYSIS OF SURFACE WAVE (MASW). Jurnal Meteorologi Klimatologi Dan Geofisika, 6(2), 15-20. Retrieved from https://jurnal.stmkg.ac.id/index.php/jmkg/article/view/119