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We present techniques to reduce noise and enhance seismic quality, making possible the first multi-attribute analysis of a 3D seismic volume in the Llanos Foothills (La Florida anticline) of Colombia using coherency and ant-tracking techniques for fault and fracture detection. The results could help reduce risk in models of reservoir fracture porosity and permeability. The dominant fracture strike direction in the studied seismic volume (La Florida anticline) is NE–SW (055 ± 20°), parallel to the structural strike of the adjacent Eastern Cordillera Foothills. The application of the ant-tracking technique also reveals the NE-SW fracture set for the reservoir rocks in the La Florida anticline as well as in the non-folded reservoir rocks to the SE. We compared the fracture intensity and orientation in folded rocks with the fracture intensity and orientation in non-folded rocks. Our study showed NE-SW, NW-SE, and E-W fracture orientations in the non-folded seismic volume, suggesting that regional stresses could produce these fracture sets, not just folding processes as previously proposed. The NW-SE and WNW-ESE fracture sets are only found in the Guayabo Formation (11 Ma–Present). A right–lateral strike–slip displacement on the nearby Algeciras fault system in the last 2 m.y. may have generated WNW-ESE and NW-SE Riedel-type shear fractures in the study area.

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Modern petrophysical software has broad capabilities for the display and manipulation of subsurface digital log data and for its integration with core data. Color and scale are two of the most important display attributes that can be used to enhance the visualization and interpretation of rock properties. The gamma-ray (GR) log, the most important log used in subsurface interpretation, is conventionally displayed on a linear scale of American Petroleum Institute (API) units. This makes it difficult to interpret in very clean lithologies with low API values or where the range of values is very large. We determine how displaying GR values on a logarithmic scale enhances the recognition of cyclicity in lithofacies with low GR values concurrently with rocks with very high API values. We further enhance the GR curve with a color-fill pattern that is intuitive and suggests the lithofacies. We calibrate the core-derived lithofacies data to the color-fill pattern, interactively “tuning” it to match lithofacies boundaries, further increasing the value of the methodology. Because of the many factors that cause variation in recorded API values, we normalized the GR curves, either by bulk shifts or statistical means, so that they display the same colors for equivalent lithologies in all wells in a cross section. We have developed two integrated studies demonstrating techniques to improve the display and interpretation of borehole logs, specifically those of Mesozoic carbonates and evaporites of the Middle East and Cenozoic siliciclastic fluvial and marginal marine systems of the Llanos Foothills of Colombia. Many examples of custom color-fill patterns for petrophysical logs could be suggested, the possibilities being limited only by the data available and the interpretation being presented.