History of Exploration and Development of Willows-Beehive Bend Gas Field: ABSTRACT

Abstract

The Willows-Beehive Bend gas field is in the center of the Sacramento Valley, approximately 70 miles north of Sacramento, California. The first gas in the area was discovered in 1937 in the old Willows gas field. A period of inactivity followed until production was developed in 1953 in the Beehive Bend field. A productive area approximately 10 miles in length and 2-3 miles wide has been delineated, with total productive limits not yet defined. The sedimentary column from youngest to oldest is: Tehama formation (non-marine Pliocene); Kione formation (marine Paleocene and/or Upper Cretaceous); and the Chico formation (marine Upper Cretaceous). Gas is produced from sands of the Kione and Chico formations which aggregate End_Page 350------------------------------ End_Page 351------------------------------ 9,000 feet. The oldest Upper Cretaceous rocks are Cenomanian in age (Goudkoff H zone), and these lie unconformably on quartz diorite, Sierra-type basement. Exploration efforts in the initial stages were based on the drilling of what appeared to be structural anomalies. Well control since has indicated that structural closure is a minor contributing factor to gas accumulation. The bulk of the gas accumulation occurs in sand lenses along the flank of a gentle southeasterly plunging nose. Traps primarily are due to lateral and updip disappearance of these sands, and to less degree, to faulting. This lenticularity of sands has resulted in a high dry-hole ratio for normal field development. End_of_Article - Last_Page 352------------