Journal
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
Volume 62, Issue -, Pages 229-242Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jsames.2015.06.006
Keywords
Neuquen basin; Mendoza province; 'Beef'; bitumen veins; Hydrocarbon migration; Fluid overpressure; Ar-39-Ar-40
Categories
Funding
- Statoil
Ask authors/readers for more resources
In the northern Neuquen Basin of Argentina (especially in Mendoza Province), there is strong geological evidence for fluid overpressure in the past. The evidence takes the form of bitumen veins and bedding-parallel veins of fibrous calcite ('beef'). Such veins are widespread in the fold-and-thrust belt of the Malargue area, where bitumen mining has been active for a century or so. So as to collect information on the development of fluid overpressure in this part of the Neuquen Basin, several old mines were visited and studied in the Malargue area. Here the bitumen veins have intruded mainly the Late Jurassic to Early Cretaceous Mendoza Group, but also the Late Cretaceous Neuquen Group. The veins have the forms of bedding-parallel sills or dykes and they are especially thick within anticlines, forming saddle-reefs in several places. Beef veins are also numerous in the Malargue area. They contain bitumen and therefore seem to have formed at the same time as the bitumen veins. Near many outcrops of bitumen and beef, we have found fine-grained volcanic intrusive bodies. The best examples are from the La Valenciana syncline. According to Ar-39-Ar-40 dating, these bodies are mainly of Mid-Miocene age. More generally, volcanism, deformation and maturation of source rocks seem to have reached a climax in Miocene times, when the subducting Pacific slab became relatively flat. (c) 2015 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available