CONGLOMERATES EVALUATION AT LISAMA FORMATION: ASSESSING NEW HYDROCARBON PLAYS IN COLOMBIA. AN EXAMPLE FROM MIDDLE MAGDALENA BASIN

摘要

The field assessed is located in the Middle Magdalenabasin at Colombia. It is currently producing from tworeservoirs including Lisama. Lisama Formation iscomposed mostly of shale with some sandstonepackages in between. The base of the Lisama formationis a very well developed sand body and is consideredthe main reservoir at the field (“Lower Sands”).According to core lithological description from one wellof the field, “Lower Sands” is divided into threesandstone packages: first, the sands at the bottom of theformation (shallow subtidal environment); the middleof the formation (conglomerates and gravellysandstone) and the upper part of the formation(sandstone package shallow subtidal environment).