Vertical-Axis Rotations During Tectonic Development of the Central Andes in Bolivia, Southeastern Peru, and Northwestern Argentina

点击翻译按钮获取中文摘要

9706193 Butler The Andean convergent margin exhibits a distinct bend centered at about 20o south latitude, coincident with the Altiplano region. Several models can possibly account for this bend, including oroclinal bending. Preliminary paleomagnetic data indicates that vertical-axis rotations have affected Cenozoic rocks units in the central Andes as far inboard as the eastern Cordillera of Bolivia. These are generally counterclockwise on the north limb and clock wise on the south limb of the bend. However, the temporal distribution of these rotations are poorly known. The goals of this project are to determine the pre-Neogene component of oroclinal bending and to define the extent and style of Eocene and Oligocene-Early Miocene deformation, including regional crustal domains and the fault that bound them. As well as providing important insights in the geodynamic development of the Altiplano, successful completion of this project would add significantly to knowledge of oroclinal structures, rotations associated with boundaries of crustal domains, and the structural development of fold and thrust belts in oroclines.