Morphometric characterization of the upper basin of the Las Lajas stream, Córdoba: A statistical analysis

Abstract

The Las Lajas creek mountainous drainage basin is characterized through the analysis of morphometric parameters, with the main purpose of studying the possible control of substrate lithology and structure on the drainage pattern. The basin drains an area of approximately 41 km², on a Precambrian-upper Paleozoic plutonic-metamorphic substrate. The basin lies in an area of moderate-elevation ranges, and planar valleys filled with alluvial and coluvial deposits. The basin is controlled by the active Las Lajas Fault. Morphometric parameters studied are: drainage density, frequency of first order streams, bifurcation relation, stream length relation, and elongation relation. These parameters were computed for third-order subwatersheds in the Las Lajas creek basin to test the hypothesis that substrate lithology controlled drainage morphometry. The statistical analysis failed to demonstrate this hypothesis. Cluster analysis indicates a grouping of subwatersheds in two major sets that do not show obvious relations to either structure or lithology of the substrate.