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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Eldridge Creek Member*
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
  • AAPG geologic province:
    • Montana folded belt
Publication:

Roberts, A.E., 1964, Geology of the Hoppers quadrangle, Montana: U.S. Geological Survey Geologic Quadrangle Map, GQ-258, 1 sheet, scale 1:24,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_712.htm]


Summary:

Named as the middle member of Cody Shale for exposures near Eldridge Creek in NE1/4 sec 27, T2S, R8E, Park Co, MT, Montana folded belt province. No type locality designated. Is a thin-bedded glauconitic sandstone that is 120 ft thick near its type section [on Eldridge Creek?]. Overlies lower shale member of Cody. Underlies upper shale member of Cody. Has a middle Niobrara fauna. Assigned to Late Cretaceous.

Source: GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Eldridge Creek Member*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Montana folded belt
Publication:

Roberts, A.E., 1965, Correlation of Cretaceous and lower Tertiary rocks near Livingston, Montana with those in other areas in Montana and Wyoming, IN Geological Survey Research 1965: U.S. Geological Survey Professional Paper, 525-B, p. B54-B63.


Summary:

[Includes some information missing from naming paper.] Is a persistent thin-bedded, greenish-gray, fine-grained sandstone 90 to 120 ft thick that forms an excellent marker in the Cody Shale near Livingston, Park Co, MT, Montana folded belt province. Contains a shallow-water marine Niobrara fauna. Assigned to the late Coniacian, Late Cretaceous. Correlation chart.

Source: GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Eldridge Creek Sandstone Member*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Montana folded belt
Publication:

Roberts, A.E., 1972, Cretaceous and early Tertiary depositional and tectonic history of the Livingston area, southwestern Montana, IN Geology of the Livingston area, southwestern Montana: U.S. Geological Survey Professional Paper, 526-C, p. C1-C120, (incl. geologic map, scale 1:62,500)


Summary:

Eldridge Creek Sandstone Member, middle member of Cody Shale. Described from composite measured section: (1) outcrop on north side of Canyon Mountain, in sec. 27, T. 2 S., R. 9 E.; (2) subsurface Deerfield Oil Corp. Strong No. 1 well, in sec. 11, T. 2 S., R. 9 E., Park County, Montana. Consists of platy to thin-bedded, very fine-grained, silty, calcareous, very glauconitic, micaceous, pyritic, greenish-gray sandstone with thin interbeds of calcareous siltstone and silty, calcareous, brownish-gray shale. Thickness 120 feet. Separated from underlying Frontier Formation by lower shale member of Cody, and from overlying Telegraph Creek Formation by upper shale member of Cody. Is a shallow-water marine sandstone. Contains fossils (pelecypods, gastropods, cephalopods). Age is Late Cretaceous (Coniacian). Report includes geologic map, correlation chart, fossil list.

Source: Modified from GNU records (USGS DDS-6; Denver GNULEX).


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Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

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