Geologic structures Middle Magdalena Valley

schematic illustration of folds produced thrust faults

faulting in middle magdalena basin reverse , thrust faulting. reverse faulting high angle in west , low angle in eastern , central areas of basin normal faults developing along eastern margin. these thrust faults formed thrusting eastern margin of central ranges in eocene , western margin of eastern ranges in miocene. major thrust faults in middle magdalena basin include infantas thrust, la salina thrust, , cantagallo thrust. basin structurally bounded palestina fault, dextral strike-slip fault system, in west , bucaramanga-santa marta fault, sinistral strike-slip system, in east.

the major surface structures of middle magdalena basin asymmetric synclines , basement cored anticlines, formed result of thrusting eastern , central ranges. thrusting initiated faulting in pre-mesozoic basement. faults pushed through jurassic layers cretaceous ductile stratigraphy. faults form horizontally @ ductile-brittle transition 10 20 kilometres (6.2 12.4 mi) before cutting through upper brittle stratigraphy. resulting structure syncline against hanging wall of fault next inclined anticline. key folds in basin hydrocarbon exploration include nuevo mundo , guaduas synclines. suggested formation of folds, both of these synclines bounded thrust faulting , anticlines.