Magnetotelluric exploration in the South of Chicontepec Basin.

Abstract:

According to the Comisión Nacional de Hidrocarburos (CNH), the peak of production in Mexico has passed the top of oil production in 2004, and to the date, it has consumed approximately 81% of its proven reserves (1P) and 57% of the possible reserves (3P). For this reason, the Chicontepec basin is considered for its proven and possible reserves of major importance for the country’s energy development.

This basin is located in the central-eastern portion of the Mexican republic, on the coastal plain of the Gulf of Mexico , inside in the oil province of Tampico – Misantla. It is made up of large volumes of sandy-clay sediments resulting from multiple turbiditic flows of submarine fan in deep water environments (Busch, 1992). These flows are a great source of hydrocarbon in many deposits around the world, so a detailed exploration and analysis of geophysical data from this site is priority. It has been geophysically investigated in various seismic exploration campaigns by private and governmental companies. But in these investigations, great uncertainties have been recorded in their measurements and interpretations, this is largely due to subvolcanic intrusions and sills which interrupt and hinder the seismic signals because they act like reflectors that mask the response of the said signals laterally and at depth (Grandis et al., 2004; Delpino et al., 2009; Pena et al., 2009; Pena, 2010).

In this investigation, we present an analysis and one preliminary 3D model of electrical resistivities from 65 broad-spectrum magnetotelluric surveys (BMT) in the southern of Chicontepec basin. In which the geometry of the basement of the basin and the main anomalies within sedimentary strata are identified, surely due to the presence of fluids, oil, gas, and/or brines. To carry out this analysis, information of wells is available from CNH, to which parametric surveys were carried out to correlate them with the response of characteristics parameters of the MT surveys. For the 3D inversion, the ModEM algorithm was used (Egbert y Kelbert, 2012; Kelbert et al., 2014).

CONACYT FC project, No. 1787.