Pg. 73, 74. Coffee Mill Hammock marl. Shell marl, 2 feet maximum thickness. Rests on fresh-water limestone at top of Fort Thompson beds. Although removed by erosion at the rapids this marl is very persistent. Is seen in place at Goodno's Landing, Fort Thompson, and at Coffee Mill Hammock [De Soto County, southern Florida], 12 miles above Labelle [La Belle]. Predominating fossil is CHIONE CANCELLATA, shells of which have been thrown out in great profusion by the dredge. [Age is Pleistocene.]
Source: US geologic names lexicon (USGS Bull. 896, p. 482).
†Coffee Mill Hammock marl. Deposits named "Coffee Mill Hammock marl" by Sellards are included in Fort Thompson formation, and name is considered unnecessary.
Source: US geologic names lexicon (USGS Bull. 896, p. 482).
Pg. 73. Name Coffee Mill Hammock marl revived and given member status in Fort Thompson formation. Member is contemporaneous with upper part of Anastasia formation. [Age is Pleistocene.]
Source: US geologic names lexicon (USGS Bull. 1200, p. 872-873).
Pg. 136 (fig. 4), 145, 146-147. Coffee Mill Hammock marl. At type locality and at most river localities, Coffee Mill Hammock marl conformably overlies a fresh-water marl or limestone and is, in turn, overlain unconformably by sands of Pamlico formation or by Lake Flirt marls. Thickness at type locality 3 to 6 feet; in some areas, marl does not form actual bed but is preserved as fillings in solution holes and pockets in limestone below. In this report, all Fort Thompson deposits that underlie Coffee Mill Hammock marl have been grouped together and named Okaldakoochee [Okaloacoochee] marl. [Age is Pleistocene.]
Source: US geologic names lexicon (USGS Bull. 1200, p. 872-873).
Coffee Mill Hammock Formation of Fort Thompson Group. Undifferentiated "Chione" shelly sand, RANGIA is dominant in the Okeechobee basin. Top formation of Fort Thompson Group. Age is Pleistocene.
Source: Publication.
Coffee Mill Hammock is retained as a separate unit of formation rank overlying the Fort Thompson Formation. Other workers have included the Coffee Mill Hammock as a member of the Fort Thompson. Age of the Coffee Mill Hammock has been determined at 0.13 to 0.11 Ma. Further work is needed to define the age and stratigraphic extent of the Fort Thompson.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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