Tectonic control on dyke and sill intrusions of active tectonic margine, case study in Cilacap area, Central Java Indonesia

Abstract

Control of geological structures on the presence of dyke and sill intrusions in the Cilacap-Central Java area requires explanation. The research was conducted through a series of fieldwork. Field research is carried out by measuring geological structural elements such as rock layers, joints, faults and folds. Geological and cross-sectional maps provide information on the distribution of igneous rock intrusions in the study area. Fault analysis produces information on the stresses forming the geological structure in the study area. Thus the relationship between the distribution of igneous intrusion and the geological/tectonic structure that controls it can be known. The main stresses forming the structure in the study area are relatively in the north-south direction. This stress creates a fault trending west-east which then becomes a channel for dyke intrusion formation.