Sacramento basin Guinda frac encouraging
An early program to frac the Cretaceous Guinda, a zone just below the staple Forbes formation in California's Sacramento basin, has yielded encouraging results, said Venoco Inc., Denver.
By OGJ editors
HOUSTON, Nov. 12 -- An early program to frac the Cretaceous Guinda, a zone just below the staple Forbes formation in California's Sacramento basin, has yielded encouraging results, said Venoco Inc., Denver.
Guinda is present under a large part of Venoco's 235,000 gross acres in the basin, where the company has more than 500 gas wells, more than 300 of which are active. However, only 9 wells penetrate the Guinda, said Timothy Marquez, Venoco's chairman and chief executive officer.
Operators in the basin's development heyday in the 1950s and 60s favored natural completions and didn't touch the Guinda, a low-permeability zone with high pressure and good gas shows, Marquez said.
Venoco ran fracs on three wells last week, including one Guinda well, and obtained a combined flow of more than 3 MMcfd. It may frac the formation in other wells later this year and has budgeted 12 Guinda fracs through 2008.
So far, the company has booked no reserves in the Guinda formation. Most of its operations in the basin involve recompletions and downspacing to 20 acres.
Venoco entered the basin in late 1996 with the purchase from the former Mobil Oil Corp. of Grimes and Willows, the state's second and third largest gas fields. The fields' reservoirs, each then producing less than 10 MMcfd, were found to be made up of lenticular rather than continuous sands. No two wells are alike, Marquez noted.
The company's 2008 budget in the basin is $130 million to drill 110 wells and rework more than 100.