GEOLOGI DAN ANALISIS MEKANISME SEDIMENTASI ENDAPAN PASIR ALIRAN SUNGAI SIRING BALAK, DESA SIRING BALAK, KABUPATEN PESISIR BARAT, LAMPUNG
Daftar Isi:
- The Research Area is in the area of Siring Balak, Pesisir Barat District, Lampung Province. The purpose of this study was to reconstruct the stratigraphy of the study area, reconstruct the geological structure, reconstruct the history of formation, analyze the history of geology, determine mean, sorting, skewness, and kurtosis in analyzing grain size and morphology of the Siring Balak River flow. The method used is field observation and laboratory analysis. Landform unit is divided into four, namely the flat-sloping decadent slope terrain, low steep slope-steep hillsides, floodplains and tortuous meandering. Three rock formations from old to young, namely Hulusimpang Formation, Seblat Formation, and Simpangaur Formation. Geological structure in form of rising faults that occur due to influence of Compression Phase on NW-SE directed Plio-Plistocene. The geological history of the area began in the Late Oligocene with formation of Hulusimpang Formation. At the end deposition of Hulusimpang Formation the process of decreasing the face of basin occurs so that Seblat Formation is deposited in the Early Miocene. In the Late Miocene - Pliocene terminated by regional subsidence motion, where siltstone lithology was deposited with the insertion of Sandstone and Tuff in the transition environment, which preceded the formation of the Simpangaur Formation and formed a fault fault structure with NW-SE direction due to the Compression Phase influence on Plio-Plistocene. The transportation mechanism is influenced by the process of bedload and suspended load.