Self-affine Behavior of Structurally Controlled River Networks. Case of Study San Cristóbal River, Cuba

Abstract

Geological structure influences the form, length and slope of rivers. An approach never used in the area is the fractal analysis for river networks, which allowed to describe and quantify the complexity of this network and associate it to geological structures and faults in the area. Self-similar fractal analysis allowed to prove the unequal river network development in longitudinal and transversal directions. The average fractal value, under self-similarity assumption, is 1,04, indicating the prevalence of straight superficial currents, tectonically controlled, while the river network fractal dimension takes values of 1,59 and 1,47. Under assumptions of self-affinity, the lacunarity dimension takes the value of 1,86 and the Hurst coefficient is 0,86, indicating the structural control on drainage. The main rivers directions coincide with zones of geological weaknesses, originated during the overthrust event, or secondary Riedel fractures related to the left-lateral movement of Pinar fault.

Keywords

• redes de drenaje
• río San Cristóbal
• fractales
• autoafinidad
• lagunaridad.