Hell Creek Formation
Hell Creek Formation is a famous Late Cretaceous and Paleocene geological formation that stretches across Montana, North Dakota, and South Dakota. Known for world-class dinosaur fossils including T. rex and Triceratops, it offers layered sediments ideal for fossilquarrying, stratigraphic studies, and understanding the terminal Cretaceous extinction. Visitors often seek guided fossil hunting, scenic exposures, and interpretive programs based on the geological heritage and fossil record.
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Geography
| Continent | North America |
|---|---|
| Region | Great Plains |
| Subregion | High Plains |
| Country | United States |
| State | Montana |
| County | Valley County |
| District | Hell Creek Formation |
| Timezone | AmericaDenver |
| Latitude | 48.264 |
| Longitude | -105.167 |
| Maps |
7:13 PM LOCAL TIMEHell Creek Formation spans approximately 200 square kilometers across northeast Montana and neighboring states, forming a relatively thin (~10-15 meter) sequence of fluvial and overbank deposits. It preserves a late Maastrichtian to Paleocene ecosystem dominated by *titanosaur sauropods, T. rex, Anzu, Pachycephalosaurus, and Dakotadactylus — with a flora of leaves, conifers, and ferns. The formation’s layered sandstones, mudstones, and claystones made it a prime river plain; fossil-bearing beds are often near channel-levee contacts or overbank deposits. Due to its age and well-preserved fossils, Hell Creek is central to research on extinction at the Cretaceous–Paleocene boundary and paleoenvironments. Visitors today find exposed outcrops and dig sites where guided tours, transient field days, and museum specimens provide insights into a world of dinosaurs*, floating fish, and early mammals. Access is mostly via local roads and trailheads near key quarries and interpretive centers.
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