Introduction Objectives Methodology Structure Pattern of Volcanic Degradation Landform of Citarik Sub-Catchment Based on Lineaments And Drainage Basin Morphometric.

Structure Pattern of Volcanic Degradation Landform of Citarik Sub-Catchment Based on Lineaments And Drainage Basin Morphometric By: Edi Tri Haryanto, Adi Hardiyono, Iyan Haryanto, Undang Mardiana Faculty of Engineering Geology, Padjadjaran University. Jln. Raya Bandung-Sumedang Km 21, Jatinangor Telp.Fax. 022 7796545 Kode Pos 45363, e-mail : ftgunpad.ac.id Website :http:ftgeologi.unpad.ac.id ABSTRACT Citarik Catchment Area, one of the main sub-catchments of Upper Citarum River Basin, found not any line structural symbol on geological maps, although some indications i.e, drainage pattern from topographical maps and linements of mountain ridges and valley based on DEM depicted clearly. Therefore the initial study to uderstand the tectonic venomena through the analysis of structure pattern, based on chatchments morphometric data and lineaments generated from Topographic Map and DEM of Global Mapper Open sources data and fieldwork has been conducted . The results could be inferred that the first order stream has three different dominant which is trending NW-SE, NNE-SSWand NE-SW, WE. The second order lineaments which still in line with the first orde catchments seems that the existence has been controlled beside by joint structure, has also been influenced directly by fault structures. Based on third order lineament, the main stress direction can generate patterns of E-W trending structure with a type of thrust fault and a normal fault, whereas the NW-SE direction and a NE-SW forming a horizontal fault. Fault structure with a N-S direction are generally normal fault type. Keywords : catchment- order, volcanic-degradation-landform, structure-pattern.

I. Introduction

Based on Regional Geological Map of Bandung and other adjacent sheets, there are many tectonic activities indicated by line faults symbols spread out the area of Upper Citarum River Basin or popularly mentioned as “Bandung Basin” or “Cekungan Bandung” figure 1. The most popular fault among the local geologists in this area is Lembang Fault located in the north of Bandung City, and many others fault based on map scattered from the west to the southeastern part of the southern slope of Bandung Basin. Curiously, there was not found any fault line symbols in the map in Citarik Catchment Area one of the main sub-catchments of Upper Citarum River Basin, , although some indications i.e, drainage pattern from topographical maps and linements of mountains ridges and valley based on DEM from Global Mapper data depicted clear enough. Joints have a close connection with the tectonic structure Harding, T. P. 1974. Joint is defined as fractures with little or no a shift ; shifting of joint structure generaly can only be observed under a microscope Ramsay, 1987, meaning that megaskopis difficult to observe a 1 shift Billing, 1972. Rock cracks or joints can be influenced by either fault structures or master joints. Stream can be ascertained controlled by joints system. Therefore the initial study based on analyzing drainage basin lineaments of Citarik Sub-catchments from maps and field work was conducted. Figure 1. Tectonic Setting of Citarik Catchment Area in the Upper Citarum Catchment Area or River Basin

II. Objectives

The objectives of study were to understand general structure pattern and tectonic fenomena on Volcanic Fluvial Degradation Landform of Citarik Sub-Catchment using characteristic of river catchments morphometric and lineaments analysis approach.

III. Methodology

Methodology used to analyse structure pattern of Volcanic Degradation Landform of Citarik Sub-Catchment were mainly Geographical Information System GIS techniques. For obtaining basin morphometric data and lineaments measured from digital topographic maps and Digital Elevation Model DEM from open sources Global Mapper programs. Constructing Rossette and Pole Diagram for analyzing joints direction, and fieldwork for obtaining joints data in the field.

IV. Location