Métodos gravi-magnetométricos modernos para analizar las características estructurales de la plataforma continental Argentina
Keywords:
Semi-empirical methods, Curie isotherm, Modelling, Double inversionAbstract
The Argentinean continental shelf will be studied by analysing the continental and the oceanic crusts, the faulting and the neighbour sedimentary basins. In the frame of an academic agreement with COPLA (National Commission on the Limits of the Continental Shelf), which leads to determine the limits of our shelf, a preliminary study on the Claromecó Basin (Buenos Aires province and the continental shelf) was performed. To the traditional gravi-magnetometric methods employed to define the model from 2D, 2½D and 3D inversions, we have incorporated the following ones to our study:
a) Semi-empirical methods: Euler and Werner deconvolution, analytical signal and gradients, which allow finding lineaments, contacts and faults.
b) Determination of the Curie isoterm from spectral analysis of magnetic anomalies (determination of the basement top and bottom depths and the Curie temperature). Its rises or falls are important to understand the actual crustal state.
c) Studies of the crustal characteristics (thickness and densities, isostatic balance) from the geoid undulations N, and the future mobility.
d) Double inversion of gravity and geoid, in order to obtain a more consistent model.
Alter the application of this methodology to the Claromecó basin, very important lineaments were found, and the isostatic balance was certified. The basin was found to present a sedimentary thickness of one third the normal crustal thickness of the area.
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