Ohio Rocks!

Lynda PriceThe Wilderness Center

This Rocks!

Sedimentary

Igneous

Metamorphic

SedimentaryRocks

Weathering ErosionDeposition

Sediments cemented by pressure over time.

Limestone

Shale

Sandstone

IgneousRocks

Cooling magma or lava forms Igneous rock.

Granite

Pumice

MetamorphicRocks

Changed by heat and pressure.

Gneiss

Slate

Geologic Time

1 million days = 2,740 years

1 million hours = 114 years

Precambrian•Basement rocks

•13,000 – 2,500 feet deep.

•Igneous and metamorphic rocks

Ohio earthquakes are caused from faults in these rocks.

Mississippian

Pennsylvanian

•Cambrian rocks not exposed.

•Oil and gas from abundant marine life.

•Warm shallow sea

•Limestone and shale

•Ohio is world famous for its fossiliferous Ordovician rocks in the Cincinnati area.

Cephalopods - squids in a shell

Crinoids – sea lilies

LimestoneDolomite

•Driveways, concrete

•Building stone

•Fertilizer

•Toothpaste, lipstick

Ocean mud

ShaleClaystone

•Pottery

•Bricks

•Concrete

•Antacids

Mud

•Dry land, then warm, shallow to deep seas

•Reef building formed barriers, restricted water flow: salts accumulated.

•Limestone, dolomite, shale, gypsum.

Salt deposits under lake Erie.

Gypsum

•Drywall

•Plaster of Paris

•Bakery products

Oceanbrine

Rock Salt

•Snow and ice control

•Seasoning

•Water softening

Oceansalt

•Dry land at first, then warm shallow seas. (Deposited the Columbus & Delaware limestone.)

•Seas became stagnant and “anoxic”. (Deposited the Ohio Shale.)

The Ohio Shale:

• Huron Shale Member

• Chagrin Shale Member

•Cleveland Shale Member

Dunkleosteus

Berea sandstone economically important.

Black Hand sandstone Hocking Hills & Mohican

•Muddy to sandy seas deposited shale and sandstone.

•Appalachian Mts. begin to form as plates collide. Supercontinent Pangea

begins to form.

Sandstone

•Building stone

•Glass

•Golf sand traps

•Furnace liners

Sand

Hocking Hills State Park

Flint

•Ohio’s official gemstone

•Spearpoints

•Flintlock guns

Volcanic ash in streams

•Tropical forests and swamps.

•Seas level rises and falls.

•Appalachian Mts. continue to rise. Supercontinent Pangea complete.

Marine rocks: shale, limestone, flint.

Non-marine rocks: conglomerate, sandstone, shale, clay and coal.

Coal

•Electric power

•Heating

•Steel production

Decayed plants

Permian

•Coastal plains swamp.

•Sandstone, shale, coal.

• Uplift and erosion

• No dinosaur fossils in Ohio

Clay

Sand & Gravel

Sand and Gravel

•Road building

•Concrete

•Groundwater source

SedimentaryIgneous &

Metamorphicrocks

Ohio Geology

Lynda PriceThe Wilderness Center

Clifton Gorge State Nature Preserve