ABSTRACT: The Argentine Eastern Continental Margin: Structure and Geological Development

Karl Hinz

Multichannel seismic data that have been acquired by German research vessels from the continental margin of Namibia/South Africa and

from the Argentine continental margin has revealed the presence of extensive wedge-shaped units beneath a thick pile of tectonically undisturbed sediments.

These units are characterized by an internally divergent pattern of reflection horizons having seaward dip. They are 50 to 100 km wide and more than 5000 m thick. They are parallel with the shelf edge and have been traced continuously for 1500 km and more.

The seismic characteristics and results of Deep Sea Drilling Project/Ocean Drilling Project drilling suggest that the wedges of seaward-dipping reflectors consist of massive volcanic rocks emplaced in a subaerial and/or shallow marine environment.

The seismic characteristics, the distribution, and the mechanism that we favor for the formation of the symmetric wedge-shaped units will be discussed.

AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990