Analysis, characterization and identification of the Meta fault (Colombia) from the distribution of resistivities

Vertical Electrical Soundings (VES) were performed between the Vichada and Casanare states in eastern Colombia, with Schlumberger arrays using maximum aperture AB = 600 m and 1 m < MN < 150 m in a region whose average elevation was 75m. Each of the eleven profiles was composed of three VES (on average), the separation between VES and the average distance between points were 417m and 6.25 km respectively; and acquisitions were carried out in late 2011 and early 2012. Resistivity values were estimated in the range of 100 Ωm to 10.000 Ωm. The apparent resistivity data were processed using the software IPI2Win, and profiles modeled possible layers with a maximum depth of research of 200 m. To the north of the study area the presence of high resistivity values (5000Ωm - 10000Ωm) is calculated, compared to those found south of the area (<3000 Ω m), these changes in resistivity are associated to changes in lithology between the north and south sections of the study area, which could be associated with the presence of a fault (the Meta fault), which has acted as a tectonic boundary. Map and Volume resistivity in the area of interest (Vichada-Casanare states), the abrupt change in resistivity is observed in the Meta fault (white line).