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Rock Formations

Measure

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Topo

Ecoregions

Public Lands

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BASEMAPS

Default Weather

Temperature

Smoke

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WEATHER

Judith River Formation (MTKjr;0)

Geologic Formation in MT

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Lithology

Geologic Age

Campanian (83.8 Ma – 72.3 Ma ago)

Geologic Unit Label

Kjr

Light brown to light gray, fine- to coarse-grained sandstone with interbeds of gray to black carbonaceous shale, silty shale, and thin coal. Local Parkman Sandstone Member (lower part of formation):yellowish gray to brownish gray and olive green, fine- to medium-grained, cross-bedded sandstone interbedded with yellowish gray, silty shale. Estuarine, brackish, and nearshore marine. Thickness as much as 305 m (1000 ft).

— USGS

Hadrosaur Hadrosauridae (family), “Hadrosaurid”

15 Observations

Chordate Fossil Chordata (phylum), “Chordates”

10 Observations

Meniscoessus GENUS

Polypodiales ORDER

Taxonomy

Geographic Places

Geological Feature

Geologic Formation

Classified As

Geologic Formation

Judith River Formation (MTKjr;0)

Judith River Formation (MTKjr;0)

Judith River Formation (MTKjr;0)