IDEAN   23403
INSTITUTO DE ESTUDIOS ANDINOS "DON PABLO GROEBER"
Unidad Ejecutora - UE
capítulos de libros
Título:
Estudio sobre el origen de CO2 en pozos de explotación petrolera en el Cerro Bayo de la Sierra Negra (Cuenca Neuquina)
Autor/es:
AGUSTO M.; YAGUPSKY D; WINOCUR D; TOBAL J; CALATAYUD F; FANTIN M; TOMASSINI F
Libro:
Actas IX Congreso de Exploración y Desarrollo de Hidrocarburos
Editorial:
IAPG
Referencias:
Año: 2014; p. 179 - 202
Resumen:
STUDY OF THE ORIGIN OF ANOMALOUS CO2 CONCENTRATIONS IN CERRO BAYO DE LA SIERRANEGRA AREA (NEUQUEN BASIN)
In the Cerro Bayo de la
Sierra Negra area (Neuquén Basin, Argentina), anomalous high levels of CO2 (65-90%) were recognized inoperating oil wells.
The hydrocarbon gasesare found in proportions lower than25%, with methaned13C values
ranging between -43 and -38 ? and the
distribution of d13C values for C1 - C3alkanes that denote an organic thermogenic origin for light hydrocarbons.
In contrast, CO2 showsd13C values
between -4 and -8 ? and suggest an inorganic origin with contributions of magmatic and carbonatic
origin. The values of 3He/4Heratio in these gases are
between 3.7 and 5.1 R/Ra,
indicating high proportion of mantle
derived He. The high relative
contents of He relative toN2-Ar allowed
to identify inorganic sources of thesegases involves both deep magmatic mantle derived and cortical material. These
values are consistent with the "plume" of low resistivity model associated with a mantle flow would affect the study
area and the thermal characteristics
of the region. It is possible the interaction processesbetween magmatic fluidsascending and Mulichincoand Vaca Muerta formations,
favor the additional
release of CO2 fromcarbonate and organic
matter of these units. Thus, the
deep magmatic mantle derived sourceis recognized as the responsible source (directly and indirectly) for theCO2 accumulations in the study area. Variations
and areal distribution of CO2 would be related to a local structural control, zones with structural
damage would favor circulation andaccumulation of deep origin fluids,
enriched in CO2and strongly related to the development of thethermal anomaly.