Exploring Sub-Basement Traps In The Upper Magdalena Valley Of Colombia

Aplicación del método de iluminación por campo de onda en un modelo subthrust en la Cuenca del Valle Superior del Magdalena (Colombia)

“…The velocity model needs to be consistent with the structural geology and stratigraphy following the sequence in age and using details about velocity information (Etris et al, 2001). For this reason; our velocity model was compound using the velocities described in Figure 3, estimated for this study area in Neiva Sub-Basin using the reported velocities in Macellari et al (2003), where used basement velocities from a stratigraphic well and we also took the velocities reported in Duarte et al (2019), where used velocity information from wells and seismic velocities. According to Yan and Xie (2016), illumination analysis by wavefield provides vital information regarding the response of an imaging system to subsurface structures.…”

“…The last years Neiva Sub-Basin have been underexplored, because the most prospective areas are associated with subthrust structures and the majority of drilled wells have been unsuccessful (De Freitas, 2000). In this context, the oil exploration is linked with the Saldaña Formation (basement) that is overlying the sedimentary sequence (De Freitas, 2000;Macellari et al, 2003).…”

“…The geology and stratigraphy of the Neiva Sub-Basin have been described in several works (Carrera-Ortiz, 2015;Jiménez-Díaz, 2008;Mojica and Franco, 1990) but due to lack of high quality in 2D seismic images and new exploration concepts (De Freitas, 2000;Macellari et al, 2003), little attention has been paid to the subthrust structures, principally in the possible prospective zones beneath Chusma, San Francisco and Upar faults. Also, the most recent (2015 -2017) 2D and 3D seismic information (which possibly has better image quality) is confidential in this area of Colombia.…”

“…Also, the most recent (2015 -2017) 2D and 3D seismic information (which possibly has better image quality) is confidential in this area of Colombia. The main target of this work is to try a 2D geophysical modelling applying wavefield illumination method, from two different seismic interpretations associated to one velocity scenario built from wells and seismic velocities (Macellari et al, 2003;Duarte et al, 2019) in a two stages methodology; in order to evaluate if the illumination could be improved for this section even in the zones under Chusma and Upar faults.…”

“…There is a structural configuration that exhibits possible structural traps located below the Chusma and Upar faults which present high dips that produce fault shadow zones. Therefore, the proposed structural styles and geological models were first studied (Blanco and De Freitas, 2003;Jiménez-Díaz, 2008;Macellari et al, 2003) and two different geological models were interpreted for the same seismic image (PSDM), taking into account that the stratigraphy in this part of the basin shows strong velocity contrasts (rocks of the Saldaña Formation overlying the sedimentary sequence) (Macellari et al, 2003;Duarte et al, 2019).…”