More than 327 million bbl of oil have been produced from Paleozoic carbonate reservoirs in 15 fields along the Cedar Creek anticline. This pronounced fold developed through a geologic history of recurrent tectonic movements along a northwest-southeast-striking fault zone. Four major periods of tectonism from early Paleozoic through mid-Tertiary are documentable in the Cedar Creek area.

Post-Silurian to pre-Middle Devonian:
Uplift and fault movement accompanied north and east tilting of the main Cedar Creek block. Several hundreds of feet of Silurian strata were eroded and a karst plain developed on the Silurian surface. Middle and Upper Devonian sediments onlapped and infilled the uplifted, northwest-plunging element.

Late Devonian to pre-Mississippian:
During latest Late Devonian and possibly earliest Mississippian, the Cedar Creek block was uplifted and tilted north and east. Extensive erosion resulted in the near peneplanation of the structure and significant truncation of Upper Devonian strata.

Late Mississippian (Chester) through Triassic:
During the Late Mississippian (Chester) and Early Pennsylvanian, the central and northern portion of the Cedar Creek area underwent gentle downwarping and periods of subsidence occurred with relative down-to-the-east fault movement along most of the ancestral master and subsidiary faults. Similar fault movement(s) and subsidence continued during the Permian and Triassic Periods. Relative tectonic stability was attained by the Middle Jurassic and essentially maintained until post-Paleocene time.

Post-Paleocene:
The Cedar Creek block underwent its greatest magnitude of uplift during post-Paleocene tectonism resulting in an extensive, linear belt of symmetric drape-folding generally aligned with the ancestral fault zones, and deep fault adjustment. During epeirogenic phases of the mid-Tertiary in the northern Rocky Mountain region, 1,500 ft (457 m) of Paleocene and Upper Cretaceous strata were eroded along the axis of the present structure.

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