STRUCTURAL MODELLING AND PETROPHYSICAL CHARACTERIZATION OF THE FRACTURED CRYSTALLINE BASEMENT RESERVOIR ANALOGS IN THE UPPER MAGDALENA VALLEY, COLOMBIA, A NEW EXPLORATION OPPORTUNITY?

Fractured crystalline basement reservoirs can contain significant hydrocarbon reserves in petroleum basins, as shown by their worldwide distribution and recent major gas and oil discoveries in Europe and Asia (England, Indonesia and Yemen). One of the major questions in this type of reservoirs is the nature of the structural network, including fracture and matrix relations, and their connectivity and petrophysical properties. The Upper Magdalena Valley Basin in southern Colombia is a mature basin characterized by Jurassic volcano-sedimentary and plutonic basement, which is commonly covered in discordance by Early Cretaceous fluvial-deltaic clastic rocks that represent the major reservoir of the basin. Subsurface evaluations have also shown that structural traps in the Upper Magdalena Valley include faulted anticlines and inverted faults that deformed the basement and the Cretaceous to Miocene sedimentary cover.
This project seeks to reconstruct the structural evolution and characterization of the fracture system that affects the Jurassic basement of the Upper Magdalena Valley by performing a multi-scale surface evaluation of the exposed basement analogues found as basin limits and intra-basin exposed highs. With this type of study, we expect to understand the spatiotemporal deformational history of the basement by using: (1) cross-cutting relationships of the fractures combined with absolute dating using low-temperature thermochronology and Ar-Ar + U-Pb direct dating of neoformed fabric minerals; (2) The regional pattern of fracturation (regional lineament and morphostructural analysis);
(3) outcrop to micro-scale fracture characterization including 1D and 2D scan-line and window analysis; and (4) complementary 1D or 2D digital analysis of outcrops captured with drone technologies. The mentioned techniques will be combined with petrophysic characterizations of the rock matrix, which will allow us to assess the reservoir quality
potential of the crystalline basement and provide decision elements for a new line subsurface exploration and the development of a new basement play in the Upper Magdalena Basin and other Colombian basins characterized by similar type of basements (Putumayo or Middle Magdalena), contributing to the future increase of hydrocarbon reserves
of the Country.

FIELD ANALOGUE
TECTONOSTRUCTURAL EVOLUTION
UPPER MAGDALENA BASIN
CRYSTALLINE BASEMENT
NATURALLY FRACTURED RESERVOIRS
FRACTURE NETWORK