Successful paleomagnetic azimuthal orientation of drill cores from a hydrocarbon source rock reservoir: The case of the Vaca Muerta Formation, Neuquen Basin, Argentina

RAPALINI, AUGUSTO E.; LUPPO, TOMÁS; IGLESIA LLANOS, MARÍA PAULA; VASQUEZ, CARLOS A.

Montevideo

Congreso; 3ra Reunion Bienal Latinmag; 2013

Asociación Latinoamericana de Paleomagnetismo y Geomagnetismo

The Tithonian-Berriasian thick bituminous shale and marls of the Vaca Muerta Formation have become in recent years a major objective of intense research for hydrocarbon exploration and production pourposes. This may represent one of the world largest unconventional hydrocarbons reservoirs. A paleomagnetic study was carried out on 193 m of drill cores from the lower and upper levels of this formation in order to determine the feasibility of an alternative orientation method of rock cores. One hundred and thirty two standard specimens from 31 samples of eight drill cores were submitted to detailed stepwise alternating field demagnetization revealing the presence of a very well defined and consistent characteristic remanent magnetization in most samples. This allowed the precise orientation of all recovered cores as well as determining the presence of intra-core relative rotations. Considering the lithological homogeneity of the Vaca Muerta Formation and the success of the paleomagnetic orientation in all cores, a standard approach using this technique in this unit is recommended. Trial of this precise and low-cost methodology in other source rock reservoirs is encouraged.