Rock Formation and Site Class in Bandar Lampung

Abstract

Soil characteristics are important impact for the scale of damage caused by earthquake vibrations. The impact caused by an earthquake in a location depends on the shear wave velocity (Vs). The study examined the effect of sedimentary rock formations on shear wave velocity and site class based on SPT tests in two rock formations in Bandar Lampung. The value of Vs, Vs30 and site class is determined based on the N-SPT value. Older rock formations of Quaternary age, have produced compaction at a shallow depth of 2 m from the surface, with Vs30 360 m/s and site class C. While the formation is younger, compactions are formed at a depth of 20 m, Vs30 200 m/s and site class D.

Identification of Deep Groundwater Aquifer Zones with Geoelectrical Method in Sukadanaham Area Bandar Lampung, Indonesia

“…In Figure 1 is a geological map in the study area that uses the Tanjungkarang geological sheet as a reference in map modification. The young volcanic sediment formation (Qhv) and the Lampung formation (QTl) are the dominant part of the cover layer in the Lampung region (Rustadi et al, 2020). The subsurface stratigraphy in the Sukadanaham Village area is still included in the young Betung volcanic deposit formation (Qhvb) which is young, namely the Holocene Quaternary is in the upper formation layer, there is an older Pleistocene formation, namely the Lampung formation (QTl), there is an older formation compared to the Lampung formation which is Eocene old, namely the Tarahan formation (Tpot), in that area there is the Undifferentiated Gunung Kasih Complex formation (Pzg) which acts as the dominant basement of the oldest age, namely Paleozoic Pre-Tertiary (Rustadi et al, 2022).…”