The Ely basin is a Lower Pennsylvanian (principally upper Morrowan) sedimentary feature which developed in the central part of the Cordilleran miogeosyncline in eastern Nevada and western Utah. The name serves to designate an area where sediments consisting of interbedded sandstone, calcareous siltstone and silty limestone, calcarenite, and micrite thicken toward a depositional center near Ely, Nevada. Marginal sediments are predominantly light-colored and well oxidized; those near the basin center are mainly dark-colored and bituminous. Sedimentary patterns differ in successive faunally recognizable subdivisions of the Lower Pennsylvanian and reflect changes in the source and distribution of sediments and in their environments of deposition.

The Ely basin area was not a persistent depositional center from Mississippian through Permian time. On the contrary, both Middle Mississippian and Upper Pennsylvanian records show a shift of the western Utah high to encompass much of the basinal area. Thus, both basinal and mildly positive elements of less than systemic duration appear to have existed in the same part of the Cordilleran miogeosyncline during the Late Paleozoic.