Fractal Dimension of Structurally Controlled River Networks of Pinar del Río, Cuba

Abstract

River networks were studied applying the fractal systems approach and based on morphometric parameters. Procedures are applied to Cangre, Los Pozos, Paso Viejo, San Diego, Los Palacios, Santa Cruz and San Cristóbal river basins (Pinar del Río, Cuba). Drainage areas were extracted taking into account isolevel lines configurations and river lengths. For every stream the Euclidian length was also estimated, to calculate the river network fractal dimension. It seems that Takayasu approach is the most appropriate to describe basins with the geological characteristics like those included in this study. The shift of order 2 streams with respect to order 1 streams is explained by the presence of drainage zones where streams have short lengths, typically in tectonically active areas. The lithologic factor seems to have influenced the drainage characteristics of Cangre basin, although, in general, the numerous faults and fractures exert a major control on every basin, which is supported by the high fractal values of Cangre, San Diego and Los Palacios basins. The Hurst coefficients of these basins are close to one, revealing a self-similar behavior of the river network. For the remaining basins it is no possible to assume a typical behavior because of the Hurst values are greater than one.

Keywords

• dimensión fractal
• tectónica
• red de drenaje
• parámetros morfométricos
• cuencas hidrográficas
• Pinar del Río