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Consejo Nacional de Ciencia y Tecnología, CONACYT: CVU 742909
Journal of South American Earth Sciences
Generically Dependent Continuant
RDF description of Geophysical determination of the Jalisco and Michoacán blocks boundaries along the Colima Graben - http://orbis.uaslp.mx/vivo/individual/scopus8955
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3D gravimetry inversion; 3D magnetic susceptibility inversion; Colima graben; Jalisco block; Michoacán block Bouguer anomaly; data inversion; geophysical survey; graben; gravimetry; magnetic susceptibility; plate boundary; tectonics; triple junction; Colima; Jalisco Block; Mexico [North America]; Pacific Coast [Mexico]; Pacific Coast [North America]
Geophysical determination of the Jalisco and Michoacán blocks boundaries along the Colima Graben
The Colima Graben is located in the southwestern part of Mexico, extending from the triple junction of the grabens of Citlala (located Southwest of the Chapala Graben), Colima and Tepic-Zacoalco south of Guadalajara, to the Mesoamerican Trench (MAT) south of Manzanillo on the Pacific coast. The Colima Graben is spatially related to the boundary between the Jalisco and Michoacán Blocks, which has been interpreted as an area of crustal rupture that facilitates the rise of upper mantle material, making it difficult to identify surface evidence to determine the limits of the Jalisco and Michoacán Blocks. The use of gravity and magnetic data inversions, make posible the determination of the boundary geometry of the two blocks, evidencing the crustal discontinuity through the contrast in density and magnetic susceptibility over the fracture zones. The Bouguer anomaly and its Analytic Signal allow the identification of a high gravimetric gradient close to the coast, between the Jalisco and Michocán blocks, that is supported by a 3D gravity inversion. The inversion also ilustrated the geometry of the tectonic units continuing from the coast to the triple junction, thus identifiying a clear separation between both blocks. Additionally, it is possible to provide evidence of the different structural trends present along the length of the Colima Graben. This is the first time where a 3D gravimetry and magnetic susceptibility inversion are applied over the full extent of the Colima Graben, resulting in the first clear definiton of the boundaries of both the Jalisco and Michoacán blocks, and showing that the Jalisco Block and Colima Graben do not adjoin each other. Instead a new distribution of the different boundaries of the Colima Graben and the Jalisco and Michoacán blocks is proposed. © 2021 Elsevier Ltd