Landsat Analysis of the Upper Cauca Basin, Colombia

James A. Noel and Sidney Sers

The Upper Cauca Basin is located in western Colombia, bounded on the west by the Cordillera Occidental and the Cauca Fault and on the east by the Cordillera Central and the Romeral Fault. It extends northward from the Patia divide to the confluence with the Rio Magdalena. Structurally, the Basin is a graben between the Cauca Fault on the west and the Romeral Fault on the east. The study area is in the Upper Cauca Basin and comprises 370,000 acres between Corinta in the south and Rio Sonso in the north.

The landsat preliminary analysis was completed by Earth Satellite Corporation. The map sheets taken from a larger mosaic were three Landsat Multispectral Scanner images: Path 9/Row 57 & 58, 1987 and Path 9/Row 59, 1976. MSS bands 4,2,1 are displayed in false colors red, green, and blue. The Cali area was refined using Path 9/Row 7 acquired in 1990.

Faults, fracture systems and folds were interpreted to be present from the lineaments and topographic features on the images. The regional Cauca, Romeral, and Palimera-Buga faults are shown. Cross faults that may be the offsets of gravity anomalies are indicated as well, and appear truncated or offset in the sediments at the Basin edges. The margins of the Basin are marked by deformed sediments presumably of Tertiary age.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California