#TITLE_ALTERNATIVE#

• Main Author: MARTHA KUSUMA (NIM: 12009073) ; (Pembimbing : Dr. Ir. Yan Rizal, Dipl. Geol.), NOVIAN
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/19076
• Institution: Institut Teknologi Bandung

The research area is located in Plabuhan area, Distric of Jombang, East Java Province. Geographically, the area is located at UTM -49 S, 9175000 m – 9179000 m dan 631000 m – 625000 m. The area is 24 km2. <br /> <br /> <br /> <br /> <br /> <br /> Morphology of the research area commonly consists of wide to close contours, with the elevation of 45 to 150 m above sea level. Morphological features are observed with contour map, Shuttle Radar Topographic Mission (SRTM) image, and direct field observation. The research area can be divided into 4 geomorphological units, consist of Anticlinal Flank Hills Unit, Anticlinal Valley Unit, Anticlinal Hills Unit, and Alluvial Plain Unit. Stratigraphy of the research area are divided into 7 unofficial lithological units from early to late: Limestone Unit, Marl Unit, Claystone Unit, Sandstone-Claysone Unit, Breccia Unit, Sandstone Unit, and Alluvial Deposit Unit. Geological Structures of the research area are Plabuhan anticline and Klitik strike-slip fault. <br /> <br /> <br /> <br /> <br /> <br /> Geological history of the research area started at Late Miocene-Early Pliocene. Here, the Limestone Unit deposited in Middle Neritic. Then in Pliocene, regression occurred at Kendeng zone triggered by an uplift, leading the deposition of shallow marine sediments (Pringgoprawiro, 1983). In Early Pliocene Marl Unit deposited at Middle Neritic. In Early-Middle Pliocene, Claystone Unit deposited at Middle Neritic. Then Sandstone-Claystone Unit deposited in Late Pliocene at Middle Neritic. In Late Pleistocene, Kendeng Zone rise to the surface, caused by the uplift wich already initiated in Pliocene. In Early Pleistocene, the Breccia Unit deposited at Shallow Marine-Terrestrial environment. In Middle Pleistocene, the Sandstone Unit deposited at Fluvial environment. According to Pringgoprawiro (1983), this Sandstone Unit , also called Cross Lamination Sandstone, has character of braided river deposite. <br /> <br /> <br /> <br /> <br /> <br /> Then, the compressional tectonic regime occurred. The main force direction was North-South. This force caused the entire lithological units in the research area formed the Plabuhan anticlinal fold. Next, this force triggered the occurrence of Klitik strike-slip fault. This fault has NW-SE trend, and dextral movement. <br /> <br /> <br /> <br /> <br /> <br /> Then, the deposition of Alluvial Deposite Unit occurred and continue until now. The exogen processes such as weathering and erosion also continue until nowdays, causing the morphology of the research area reach the recent state.