Field Studies of Breton Sound Blocks 37, 39 and 49, Offshore Louisiana
C. J. John, B. L. Jones, B. J. Harder, R. J. Bourgeois, and R. P. McCulloh
Louisiana Geological Survey, Baton Rouge, LA
Basic geological information on individual oil and gas fields are not commonly found in the geologic literature. This study is designed as part of a series of field studies being conducted at the Louisiana Geological Survey to fill this need. Deltaic depositional environments, often in conjunction with structural elements have created significant oil and gas accumulations in South Louisiana and the Breton Sound area is no exception. Data presented includes structure maps, type log, number of wells, productive horizons and depth, cross sections, Louisiana Office of Conservation orders and production information. The Breton Sound Block 37 field discovery well was drilled to a depth of 8,865 ft and completed in August, 1966. Since that time 23 wells have been permitted. The field is located on a west-northwest trending anticlinal structure bisected by an east-northeast striking south dipping normal fault. Twelve producing zones in this field range in depth from 2,650 ft to 7,802 ft and are of Middle-Upper Miocene age: Block 37 has produced (1966-1998) 15,209,364 mcf of gas, 1,905,981 bbls of oil, 105,202 bbls of condensate and 3,087,911 mcf of casinghead gas. The discovery well in Block 39 field was completed in July 1966 and has a total depth of 13,100 ft. Ten wells have been permitted, and the two productive zones in this field range in depth from 6,270 ft to 7,538 ft (Middle-Upper Miocene). The field is associated with a subtle closure on the downthrown block of a northeast- striking down-to-the-basin fault, and with a small horst block upthrown to this fault where it is joined from the west by an eastwest striking and north dipping normal fault. This gas field has produced 1,629,465 mcf gas through the end of 1998. The Breton Sound Block 49 field discovery well drilled to a depth of 10,082 ft was completed in March 1961 and nine wells have been permitted. The field has two productive zones ranging in depth from 8,836 ft to 11,344 ft (Middle Miocene) and a domal structure broken by an east-northeast and a southeast-striking fault. Field production totals (1961-1998) are 54,613 mcf of gas, 202,147 bbls of oil, 1,692 bbls of condensate and 1,865,418 mcf of casinghead gas.
AAPG Search and Discovery Article #90901©2001 GCAGS, Annual Meeting, Shreveport, Louisiana