ESCUQUE, Formation

TERTIARY (probably middle Eocene)

State of Trujillo, Venezuela

Author of name: M. L. Krueger, 1927 (private report).

Original reference: A. Salvador, 1950, Ph. D. Thesis, Stanford University.

Original description: ibid.

The name Escuque was introduced by M. L. Krueger (private report) for exposures of this formation in Rio Caús and Quebrada Honda, 15 kilometers west-southwest of the town of Escuque. The formation was later described by A. Salvador (1950) who selected as type locality the Alto de Escuque, a prominent ridge north of the town of Escuque.

According to Salvador (1950) the formation is composed of light to dark gray, thick-bedded to massive, medium to coarse-grained occasionally conglomeratic, quartzitic sandstones. Beds of brownish to grayish sandy shale, from an inch to 10 feet in thickness, are commonly interbedded with the sandstones. The Escuque formation varies in thickness from about 1,200 feet in southwestern Trujillo (Río Caús; Krueger, private report) to 130 feet in northern Trujillo (Chejendé; Salvador, 1950). Outcrops of the formation extend along the Andean mountain front from southwest Lara through Trujillo, southeast Zulia and northern Mérida.

The Escuque conformably overlies either the Ranchería or Valle Hondo formations, and is overlain conformably by the Caús formation. The contact with the Caús is sharp but with no indication of erosional surface or hiatus.

With the exception of occasional Nalymenites, the formation is barren of fossils; however, the age is determined as upper middle Eocene or possible lower upper Eocene due to its position overlying the Valle Hondo formation (Salvador, 1950; de Cizancourt, 1951, p. 47).

The Escuque formation is believed to be the equivalent of the "main sandstone" of Tash (1937, p. 167-168), the Mirador formation in Táchira, the Misoa sandstone of Liddle (1946, p. 325-331) and of González de Juana (1951, p. 274-275, 285). It is not equivalent to Sutton's Misoa as he included the Cuicas member (Valle Hondo formation) at the base (1946, p. 1666-1669).

Gordon A. Young