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You are here: Categories > Time periods > Geologic time periods > Phanerozoic > Paleozoic

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PDF Assessment of undiscovered oil and gas resources of the Devonian Marcellus Shale of the Appalachian Basin Province [More info]
We estimated a mean undiscovered natural gas resource of 84,198 billion cubic feet and a mean undiscovered natural gas liquids resource of 3,379 million barrels using a geology-based assessment methodology.
Divisions of geologic time-major chronostratigraphic and geochronologic units [More info]
Revised geologic time scale indicating the ages of the lower bounds of chronostratigraphic and geochronologic units as they are currently known. Modifications to those ages made since the previous time scale was released (2007) are clearly marked.
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