Watershed characteristics of West Progo dome and its implications on neotectonic

Abstract

Abstract This geomorphological study discusses the characteristics of the watershed that compose the West Progo Dome, conducted using a field survey method, topographic map analysis, and remote sensing imagery. This is because the West Progo Dome is built by two different litology characteristics (volcanic and carbonate rocks) and different age. Analysis of watershed characteristics includes area, flow pattern, bifurcation ratio (Rb), and river density (Dd), accompanied by statistical analysis of the T2-Hotelling multivariate mean difference test. The results shows that the West Progo Dome has three large watersheds, namely the Bogowonto, Serang, and Progo watersheds, with an area of about 270.4, 110.9, and 140.3 km2, respectively. The drainage patterns in this area are dendritic, radial, sub-parallel, trellis, rectangular and angulate. Rb of drainage in the study area varies from low to high, indicating the presence of tectonic influences. The Rb value in System IIA is 2.0 - 5.8, and in System III is 1.290 - 6.630. The Dd value on System IIA is 0.921-1.592 km/km2 and on System III is 0.990-1.200 km/km2. This very rough Dd also indicates the presence of tectonic influences. The average Rb and Dd values between System IIA and System III were not significantly different. It means that tectonics influences the watershed morphometry in the West Progo Dome and is still active until the Quaternary (neotectonic).