Ayala, C., et al., 2017. High resolution magnetic, regional gravity and petrophysical characterization of the Dominican Republic tectonic domains with special focus on the Central Cordillera. Boletín Geológico y Minero, 128 (3): 611-631 ISSN: 0366-0176 DOI: 10.21701/bolgeomin.128.3.005 611 High resolution magnetic, regional gravity and petrophysical characterization of the Dominican Republic tectonic domains with special focus on the Central Cordillera C. Ayala (1,2) , J. L. García-Lobón (1) , J. Escuder-Viruete (1) , C. Rey-Moral (1) , A. Pérez-Estaún (3, †) y A. Padín-Debén (4) (1) Geological Survey of Spain (IGME), C/ La Calera n. 1, 28760 Tres Cantos, Madrid. Tl.: +34 917287218, Fax: +34 917287202 c.ayala@igme.es; jl.garcia@igme.es; j.escuder@igme.es; c.rey@igme.es (2) Now visiting at the Institute of Earth Sciences Jaume Almera-CSIC, C/ Lluís Solé i Sabarís s/n, 08028 Barcelona.
ABSTRACTThe aim of this study is twofold: to make a geological interpretation of available ground gravity and high resolution airborne magnetic surveys carried out over the Dominican Republic, and to define the spatial limits of key tectonic units of the Central Cordillera. Potential fields and petrophysical data allow the establishment of the spatial limits and the relationships of the key tectonic units at local and regional scale. Therefore, gravity and magnetic data have been integrated to produce models of the upper crustal structure across the Central Cordillera following corresponding geological cross-sections that have been extended in depth. Since there are no seismic or borehole data to constrain the models in our study area, modelling is based on potential field data and the analysis of the physical properties that have been measured from surface rocks (586 density and magnetic susceptibility samples). The main features of the potential fields maps are: (1) NW-SE-trending anomalies delineating the main tectonic units, which coincide with the major strike-slip fault zones that limit those units; (2) exceptional geophysical mapping examples of volcano-sedimentary units; and (3) significant anomalies due to a magmatism widely spread all over Hispaniola Island. The modelling results reveal the petrophysical heterogeneities and subsurface geometry of the tectonic units, faults and shear zones. The model shows that Tireo Fm extends up to 7 km in depth. The Duarte Complex has been modelled as a layer of c. 5-7 km in thickness beneath the Tireo Fm and the S. Juan Basin. Some of the intrusive bodies may reach depths of c. 8 km.Key words: Central Cordillera-Dominican Republic, Density, Geophysical mapping, Magnetic susceptibility, Potential field modelling.Caracterización de los dominios tectónicos de la República dominicana, con especial énfasis en la Cordillera Central, mediante datos aeromagnéticos de alta resolución, gravimetría regional y petrofísica Presente (e.g. Mann et al., 1991, 1995 (Bowin, 1975;Lewis and Draper, 1990;Mann et al., , 1995 .
Contexto geológico
La geología de La Hispaniola está formad...