RICOA, Formation

TERTIARY (upper Oligocene)

State of Falcón, Venezuela

Author of name: H. G. Kugler, 1946 (private report).

Original reference: A. L. Payne, 1951, p. 1854.

Original description: ibid., p. 1856, 1857.

Payne (1951, p. 1856, 1857) stated that the Ricoa formation of upper Oligocene age is the oldest formation exposed in the Cumarebo area. It is essentially argillaceous. He pointed out that a thickness of 8,000 feet has been computed for the thickness of the Ricoa in the type area. Payne mentioned that the thickness is made up of 2,000 feet of Acurigüita shale and of a rest of 6,000 of the formation. However, the thickness may be greater than 8 000 feet, inasmuch as the Acurigüita shale was approximately 3,900 feet thick in the well Las Pailas N° 1, the only well in which this shale was completely penetrated. The three sand members, the Turaguapo, Solito and Lomas sands, though well developed at and near the type surface localities, shale out or lense out on the north, northeast, and east, as indicated by surface geology and by subsurface data.

Most geologists now consider the Ricoa formation to be equivalent to the combined Agua Clara, Solito and Querales formations They regard the Turaguapo sand and the Acurigüita shale as middle and lower members, respectively, of the Agua Clara formation in the Cumarebo area. The Solito sand is given formation rank and the Las Lomas sand is carried as the upper member of the Querales formation in the Cumarebo area.

Leo Weingeist