Eagle Ford; Hydrocarbon quality prediction from mud-gas logging while drilling
Angel Callejon, Tao Yang, Lisset Sousa, Remy Basquet, Michael Ghazizadeh, Alfonso Zaza and Alison Faust
Statoil farmed-in a joint venture with Talisman Energy in the Eagle Ford play in 2010. Fifty one PVT analyses from hydrocarbons collected from the Cretaceous Eagle Ford Formation where interpreted and integrated with geological and geochemical information to derive a protocol that allows the prediction of the quality and nature of hydrocarbons encountered while drilling.
At this point the evaluated data prove that a mud-gas systems with constant volume and temperature best represent the gas composition from the formation. Variations inside the formation still needs further investigation and the relation between chemical composition and our developed Gas Index may help to identify sweet spots in unconventional reservoirs