Abstract
In the Upper Magdalena Valley, 70 kilometers south of Neiva La Hocha Field is located, on the low side of the San Jacinto Fault, structurally defined by a "Z" type anticline with dips between 45 and 90 degrees. Its geological information is obtained from wells and is standard requirement to run image logs to characterize the structure dip and fracture behavior. Uncertainty related to fractures trends and structural dip, are principal reasons of this analysis.
Micro resistivity image interpretation, core data, core tomography images, field closeness to a regional fault (between 0 and 600 meters) and reservoir production information have allowed identifying it as naturally fractured. Recently, a core was acquired, analyzed with high resolution tomography and integrated with micro resistivity image logs, to characterize and integrate the rock with well logs, then to extrapolate the results to other wells in the field.
The integration allowed confirming planes originally associated with structural dips, identifying fractures on the core that the image log resolution did not permit, interpreting fractures using core tomography radial images, similarly as in image logs. Several features were interpreted and based on fracture dip and strike direction three fracture families were defined, with a predominant strike direction of NW-SE.
This combined analysis helped to establish a fracture trend pattern or criteria that represents great information for future fracture and structural models in La Hocha field. Additionally, this pattern will be extrapolated to other wells with micro resistive image log in the field, adjusting and improving those results, obtaining a better model.
