John Strong Newberry, director of the Ohio State Geological Survey, first identified the formation in 1870.

[2][4] It is fairly fissile,[6][5][7] breaking into thin, irregularly shaped sheets[10] or flakes[4] that occasionally display crystals of pickeringite.

[2] Relieved of stress once exposed, the Cleveland Shale is nonplastic[4] and can appear as if fragmented into blocks due to jointing.

[7] Portions of the pyrite layer, known as Skinner's Run Bed,[7] contain fragments of petrified wood and fossilized fish bones worn smooth by the action of water.

[14][15] Thin beds of gray or brown siltstone, lumps of pyrite, and layers of silica-heavy limestone with cone-in-cone structures are found in the lower part.

[5] The lower part is famous for its extensive and well-preserved fossil Chondrichthyans (including Cladoselache), Conodonts, Placodermi,[7][5] and palaeoniscinoids ray-finned fishes.

[22] The giant predatory placoderms Dunkleosteus terrelli, Gorgonichthys clarki, Gymnotrachelus hydei, Heintzichthys gouldii, and five subspecies (including the type specimen) of Titanichthys were all discovered in the Cleveland Shale.

Typical early shark preservation includes soft tissue outlines and impressions, fin rays, gill musculature, cartilage, and stomach contents.

[36] Other undescribed osteichthyans (bony fish) from the Cleveland Shale include a new species of Kentuckia and an unnamed Mesopoma-like palaeoniscoid.

[47][26] The Cleveland Shale is approximately 362.6 to 360.1 million years old, daing to the very latest part of the Devonian period, the Famennian,[14] based on biostratigraphy from conodonts[15] and plant spores.

This led to a significant drop in marine oxygen (an anoxic event) and atmospheric carbon dioxide, and then a brief glaciation.

[51] While the Cleveland Shale was being deposited, extensive organic matter from the land was swept into the sea then lying over Ohio.

[52] Although there is dispute over how deep this sea was, the Dasberg event meant that oceans could support few to no bottom-dwelling animals.

This feature is interpreted as having been caused when two different depositional environments (in this case, the oxygenated sea which laid down the Chagrin Shale and the anaerobic sea rich in organic matter which laid down the Cleveland Shale) moved repeatedly back and forth over the same area.

This likely led to exposure and erosion of the Cleveland Shale, with sediment which became the Bedford Formation filling in these gullies.

They also observe that there is evidence of diapirism (the intrusion of deformable Cleveland Shale upward into the more brittle Bedford Formation), as well as intertonguing.

[7] The high organic content of the Cleveland Shale makes it eminently suitable for the formation of fossil fuels.

One 1981 study found that the Cleveland Shale can yield an average of 14 US gallons (53 L; 12 imp gal) of petroleum per 1 short ton (0.91 t) of rock.