Ohio geology 8th grade power point new and improved

Ohio Rocks!

Lynda Price
The Wilderness Center










This Rocks!

Sedimentary
Igneous
Metamorphic


Sedimentary
Rocks
Weathering
Erosion
Deposition
Sediments
cemented by
pressure
over time.

Sandston
e

Limeston
e

Shale


Igneous
Rocks
Cooling
magma or
lava forms
Igneous
rock.


Granite


Metamorphic
Rocks

Changed by
heat and
pressure.

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


Limestone
Dolomite
•Driveways, concrete
•Building stone
•Fertilizer
•Toothpaste, lipstick

Ocean
mud


Shale
Claystone
•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
Ocean
brine
•Drywall
•Plaster of Paris
•Bakery products