There is a wide range of crudes in the basin, going from heavy oil to condensates. The best quality oils are located at the foothills (Cusiana condensate) and the northern part of the basin (Caño Limón light oil).
Inside the Eastern Llanos Basin, most of the stratigraphic sequence is immature. However, in the foothills the sequence reaches the late oil and gas window, producing the condensate in the Cusiana field. Kerogen type varies between II and III, being of type II in the foothills and of type III in the foreland. Most samples have less than 2% TOC, but there are intervals with higher values.
The generative potential ranges between 0 and 90 mg HC / g Rock with most samples below 10 mg HC / C Rock. Regarding gas, the C2/C3 vs. d13C + CH4 (ppm) diagram suggests that gas samples are the result of a variety of processes such as mixing, differential thermal maturity and biodegradation. Nevertheless, the C2/C3 vs. d13C C2 - d13C C3 diagrams suggest that most of the analyzed gas samples were originated by primary cracking.