Name applied to predominantly siltstone sequence in upper part of Tyee formation. Member is more argillaceous than underlying part of the Tyee formation or overlying Coaledo formation. Thickness about 2,000 feet. Member not present beneath Coaledo formation in southwestern part of mapped area either because the siltstone grades laterally into sandstone west of its outcrop or is overlapped by Coaledo formation. Member crops out in southern part of Elkton quadrangle and in easternmost part of Scottsburg quadrangle, and extends beyond south border of mapped area.
Typical strata well exposed in cut along Henderer Road, 1.5 miles west of Elkton, Douglas Co., and in banks of Umpqua River in that vicinity. Entire member exposed between SE/4 sec. 23, T. 22 S., R. 9 W. (base of member), and center of sec. 8, T. 23 S., R. 8 W. (top of member), in cuts along road that parallels lower part of Luntsinger Creek.

Source: US geologic names lexicon (USGS Bull. 1350, p. 240).

Pg. 16. Elkton Siltstone Member of Tyee Formation. Bird (1967) elevates the Elkton Siltstone, Sacchi Beach Siltstone, and the [Lorane] Siltstone Members of the Tyee Formation to formational status under the term of Elkton Formation, and Lovell (1969) treats the units as a formation on his correlation chart. The member status of the units is retained here, however, because the thesis of Bird does not constitute adequate publication for establishing a formation. Moreover, the article of Lovell does not propose to establish a formation, nor does it provide a description or a type locality.
References cited:
Bird, K.J., 1967, "Biostratigraphy of the Tyee Formation," Univ. Wisconsin PhD thesis [unpub.], 209 p.
Lovell, J.P.B., 1969, GSA Bull., v. 80, p. 9-22.

Source: Publication.