Pg. 184 (fig. 68) [preprint 1941]. Elder Creek group. Shown as lowermost group of Knoxville series. Underlies Grindstone group (new). Age is Late Jurassic (Knoxville).

Source: US geologic names lexicon (USGS Bull. 1200, p. 1224-1225).

Pg. 924, 925-926. Elder Creek group. Basal beds, as exposed near Redbank Creek, consist of dark-reddish-brown greatly indurated shale or thin-bedded cherty strata standing at a high angle and in part slightly overturned. In Bennett Creek area, a thick succession of alternating thin-bedded shales and calcareous sandstone layers constitute major part of group. Maximum thickness 6,600 feet. To the north, group is overlapped by early Shasta (Paskenta) beds; farther south, it is overlapped by conglomerates of Grindstone group. Lowest exposed beds rest upon or against pre-Knoxville meta-andesite of Klamath complex. Age is Late Jurassic (Knoxville).
Traceable northwest from Redbank Creek for a short distance and toward the south for more than 40 mi to latitude of Elder Creek village, Tehama Co., northern CA.

Source: US geologic names lexicon (USGS Bull. 1200, p. 1224-1225).