Summary
Authors: Carlos Ortiz (presenter), Daniel Fernández, Jorge Galeano, Aldo Rincón, Camilo Montes, Felipe Lamus, Universidad del Norte
Presentation in Spanish.
The Magdalena River is the most important fluvial system in the northern Andes; its delta is located in the Colombian Caribbean Basin and represents one of the largest submarine fans in the world. The evolution of the Magdalena River paleo-delta is recorded in the upper Miocene-lower Pliocene units deposited near its current mouth. Previous studies have proposed a late Neogene - Pleistocene migration of multiple paleo-deltaic lobes, and more recently, the paleo-delta dynamics have been tentatively linked to regional paleoclimatic events during early Pliocene times. To identify Spatio-temporal changes in depositional environments associated with the evolution of the Magdalena river paleo-delta, we carried out detailed mapping of the late Neogene units in the area and analyzed facies associations and stacking patterns in three stratigraphic sections, providing a new interpretation of the previous stratigraphic data. We identified progradational deltaic environments interpreted during late Miocene times, with a westward progradational shift in deltaic facies in early Pliocene times. These changes in the Spatio-temporal distribution of the facies suggest a westward migration of the paleo-delta in a progradational phase during early Pliocene, leading to the deposition of calcareous foreshore deposits to the east of the mapping area, and deltaic deposits in marginal marine environments to the west. Eastward thinning and reduction of siliciclastic input previously identified in the lower Pliocene sequence reinforce this hypothesis and could explain the onset of the great influx of siliciclastic sedimentation in the western upper Magdalena submarine fan.
Bio:
Carlos Ortiz, Universidad del Norte
Carlos is a Geologist from the Universidad del Norte, Colombia.
Please log in to view or purchase the video presentation