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Detailed Reference Information
Counil et al. 1989
Counil, J., Achache, J. and Galdeano, A. (1989). Long-wavelength magnetic anomalies in the Caribbean: Plate boundaries and allochthonous continental blocks. Journal of Geophysical Research 94: doi: 10.1029/88JB04163. issn: 0148-0227.

Vector magnetic anomaly maps are derived at satellite altitude from Magsat data over the Caribbean and Middle America. To minimize smoothing of the anomaly field caused by averaging the data over the whole altitude range of Magsat measurements, two maps are derived in two nonoverlapping altitude ranges: 350--420 and 420--550 km. A composite map of the vertical component of the anomaly field is then computed at ground level. This map displays large positive anomalies associated with fast subduction zones. These anomalies define discontinuities in the downgoing slab associated with seismic gaps. Positive anomalies are also consistently observed above allochthonous blocks of continental origin in the Caribbean area and suggest that the average magnetization is larger in the continental lithosphere. Elongated magnetic lows are observed above transform boundaries of the Caribbean plate. The Cayman Trough anomaly is consistent with magnetization of the order of 1 A/m in the upper mantle. Demagnetization of the lithosphere along the Bocono-El Pilar fault system which bounds the Caribbean plate to the south may be accounted for by along shear frictional heating zones. The pattern of anomalies anomalies along the southern margin of the United States is related to its accretionary tectonic history. Various estimates of the vertically integrated magnetization of both oceanic and continental lithospheres are computed using these anomalies and provide constraints on the vertical distribution of lithospheric sources of Magsat anomalies. ¿ American Geophysical Union 1989

BACKGROUND DATA FILES

Abstract

Keywords
Tectonophysics, Plate boundary—general, Information Related to Geographic Region, Atlantic Ocean
Journal
Journal of Geophysical Research
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Publisher
American Geophysical Union
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