Abstract

PEDRAZA DE MARCHI, Ana Carolina  and  TOCHO, Claudia. Análisis de nuevos estándares para reducir datos de gravedad: aplicación en Tierra del Fuego. Geoacta [online]. 2011, vol.36, n.2, pp.151-166. ISSN 1852-7744.

The main objective of this study was to investigate the use of new standards and procedures for reducing gravity data in order to improve the precision, accuracy, and usefulness of geophysical gravity anomalies. The new standards take into account the increased current computing power, the modern satellite technology to determine the height and positioning of the gravity stations, the improved topographic / bathymetric databases, and new mathematical algorithms. They are based on internationally accepted procedures, protocols, equations and parameters, and in many cases differ from those presented in current geophysical textbooks and existing gravity databases. The most important change that the new standards suggest, due to the greater use of Global Positioning System (GPS) for field gravimetric work, is the use of terrestrial reference ellipsoid adopted internationally to define the vertical datum. The anomalies calculated with the new standards could be modified by the adjective "ellipsoidal" to differentiate them from the anomalies calculated by conventional elevations referred to the geoid. Gravity reductions, following the traditional and new recommendations and standards were calculated in the province of Tierra del Fuego. We used digital elevation models and geopotential models to assess the effectiveness of its use in gravity reductions. The land gravimetric data were integrated with free air anomalies derived from satellite altimetry in the sea, in order to compute an ellipsoidal isostatic anomaly map.

Keywords : New gravity reductions standards; Ellipsoidal anomaly; Indirect geophysical effect; Tierra del Fuego.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )