MENE GRANDE, Formation

TERTIARY (upper Eocene)

State of Zulia, Venezuela

Author of name: R. Arnold, 1915 (private report).

Original reference: G. E. Tash, 1937, p. 165.

Original description: ibid.

The name Mene Grande series has first been used by Arnold, geologist of Caribbean Petroleum Co. in private reports. Tash (1937, p. 165) gives the first full description quoting directly from Arnold's report of 1915. The name is taken from the Mene Grande oilfield, in the district of Baralt, southeastern Zulia, where the best section is found in a small quebrada which originates near the north end of the Mene Grande oil seep and runs west toward the lake. According to Tash (1937, p. 165-166) the term Mene Grande series was used for the upper member of the Paují formation which is described as follows (Dagenais, quoted by Tash): the upper part of the Paují shale is made up of a succession of thinly bedded, dark gray sandstone and black shale. Occasional reefs and lenses of orbitoidal limestone are in places intercalated with the sandstone. The approximate thickness of this sandy phase of the Paují is about 328 feet. According to Tash, the Mene Grande varies in thickness from 75 to 475 meters. The Mene Grande formation rests on the Paují formation with apparent conformity, it is covered discordantly by the nonmarine Miocene Isnotú formation, according to Sutton (1946, p. 1685).

Sutton (1946, p. 1685) uses the name Mene Grande formation, as well as the Staff of Caribbean Petroleum Co. (1948, p. 569) and Liddle (1946, p. 376).

The Mene Grande formation, like the Paují formation, is upper Eocene in age, and both formations have many foraminiferal species in common. The Mene Grande can be readily distinguished by the presence of certain species of larger foraminifera and species of Bathysiphon, Bulimina, Cassidulina, Cibicides, Clavulina, Dorothia, Globigerina, Spiroplectammina, Textularia, Trochammina, Uvigerina, Verneuilina and Valvulina, according to Tash (1937, p. 170). For fossil lists of larger foraminifera determined by various paleontologists, see Sutton (1946, p. 1686).

The Mene Grande formation crops out near the Mene Grande oilfield and extends from the Rio San Pedro northward as far as the Santa Bárbara-Los Barrosos road. According to the Staff of Caribbean Petroleum Co. (1948, p. 569), the thickness of the Mene Grande formation observed in the Mene Grande field ranges from almost nothing to 120 feet, but east of the field, in the Raya syncline, the total thickness is estimated to be about 2150 feet.

The Mene Grande formation of Garner (1926, p. 682) consists of alternating massive, brown and, red, coarse, soft sandstones and white to brown ferruginous clays, outcropping in the hills immediately north of Mene Grande.

The age indicated by Garner is Miocene and it is possible that these sediments are post-Eocene indeed.

W. A. Mohler