A new nascent spreading centre at the Wagner Basin in the northern Gulf of California: a possible geothermal resource?

The probable geothermal reserves of Mexico sum up to only 1400 MW; however, they have been estimated on the basis of the high temperature systems and do not include the unconventional geothermal sources. Submarine hydrothermal systems may become in the near future a feasible energy source, especially those that occur at shallow depths. Recently discovered hydrothermal activity in the Wagner Basin may be harnessed to produce electricity using an environmentally friendly system

Biogenic vs geochemical precipitation of minerals in the submarine hydrothermal vents of Punta Mita, Mexico

The submarine hydrothermal vents located in the vicinity of Punta Mita contain abundant deposition of calcite, pyrite. Also present are barite, carbonate hydroxyl-apatite, cinnabar and T1-sulfide.Textures indicate direct deposition for calcite and pyrite; however, pyrite also replaces magnetite in the host rock. Thermal water was filtered and microscopic analysis of the particles fiom the filters shows that the shape of the crystals varies euhedral crystals of pyrite to globular aggregates that may be interpreted as a mixture of chemical and biogenic precipitation. Isotopic signature of sulfur in pyrite and carbón in calcite indicates that biogenic deposition is an important phenomenon in this hydrothermal systemPeer ReviewedPostprint (published version

Estudio mineralógico de los sedimentos de las cuencas de Wagner y Consag, Golfo de California (México)

Peer ReviewedPostprint (published version

Boundary conditions in thermal models : An application to the KTB site, Germany

International audienceDeep temperature estimations are important for Theological studies of the crust and also for the planning of deep drill holes. Thermal modeling requires the input of realistic boundary conditions in order to obtain reliable values for the temperature at depth. Boundary conditions necessary for thermal models may be inferred from geochemical and geophysical parameters measured in the field. Numerical solutions of heat equations can be obtained through finite element and finite difference schemes in one, two or three dimensions, taking into account several assumptions regarding the medium parameters, such as homogeneity and anisotropy of thermal conductivity. In this paper we present one and two-D models and highlight the differences between them. The Oberpfalz area was selected to test the model and boundary conditions, because geochemical and geophysical data were available to estimate the boundary conditions in our model and temperatures at depth have been actually measured at the KTB borehole. A good agreement between the calculated and measured temperatures is obtained for a 2-D model with appropriate boundary conditions from geochemical and geophysical data.Las estimaciones de la temperatura a profundidad son de suma importancia para los estudios reológicos de la corteza y también para una planeación correcta de la perforación de pozos profundos. La modelación térmica requiere de condiciones de frontera reales, para así poder obtener valores confiables de la temperatura a profundidad. Las condiciones de frontera necesarias para los modelos térmicos pueden ser inferidas a partir de parámetros geoquímicos y geofísicos medidos en el campo.Se pueden obtener soluciones numéricas de las ecuaciones de transferencia de calor a través de modelos de elementos finitos o de diferencias finitas para una, dos o tres dimensiones, tomando en cuenta varias suposiciones en relación con los parámetros del medio, tales como homogeneidad y anisotropía de la conductividad térmica. En este trabajo presentamos modelos uni- y bi-dimensionales y resaltamos las diferencias entre ambos.El área de Oberpfalz fue seleccionada para probar el modelo y las condiciones de frontera debido a que los datos geoquímicos y geofísicos se encontraban disponibles para estimar las condiciones de frontera, ya que las temperaturas a profundidad habían sido medidas en el pozo KTB. Se encontró concordancia entre las temperaturas medidas y las calculadas para el modelo bidimensional que incluía condiciones de frontera inferidas a partir de los datos geoquímicos y geofísicos

Biogenic vs geochemical precipitation of minerals in the submarine hydrothermal vents of Punta Mita, Mexico

The submarine hydrothermal vents located in the vicinity of Punta Mita contain abundant deposition of calcite, pyrite. Also present are barite, carbonate hydroxyl-apatite, cinnabar and T1-sulfide.Textures indicate direct deposition for calcite and pyrite; however, pyrite also replaces magnetite in the host rock. Thermal water was filtered and microscopic analysis of the particles fiom the filters shows that the shape of the crystals varies euhedral crystals of pyrite to globular aggregates that may be interpreted as a mixture of chemical and biogenic precipitation. Isotopic signature of sulfur in pyrite and carbón in calcite indicates that biogenic deposition is an important phenomenon in this hydrothermal systemPeer Reviewe

Benthic foraminiferal assemblage counts from the Gulf of California

Extensive CO2 vents have been discovered in the Wagner Basin, northern Gulf of California, where they create large areas with lowered seawater pH. Such areas are suitable for investigations of long-term biological effects of ocean acidification and effects of CO2 leakage from subsea carbon capture storage. Here, we show responses of benthic foraminifera to seawater pH gradients at 74-207 m water depth. Living (rose Bengal stained) benthic foraminifera included Nonionella basispinata, Epistominella bradyana and Bulimina marginata. Studies on foraminifera at CO2 vents in the Mediterranean and off Papua New Guinea have shown dramatic long-term effects of acidified seawater. We found living calcareous benthic foraminifera in low pH conditions in the northern Gulf of California, although there was an impoverished species assemblage and evidence of post-mortem test dissolution

Estudio mineralógico de los sedimentos de las cuencas de Wagner y Consag, Golfo de California (México)

Peer Reviewe