A trip through the geographic time scale in the not so magical

school bus. .

MSPG 2010

BRYAN COUNTY AREABRYAN COUNTY AREA

.

.

Dexter Sandstone• Approximately 90 million

years old• Kwd (Cretaceous System, Gulfian Series,

Woodbine Formation, Dexter Member, Dexter Sandstone)

• Sandstone is formed from sediment cemented together from particles found in shallow oceans

• Yellowish-brown, fine to medium grained, clay ironstone beds

BRYAN COUNTY AREABRYAN COUNTY AREA

……..

Bennington Limestone• Bokchito Formation of the Cretaceous Period• Blue-gray• Heavy bedded to massive• Line to medium• Crystaline Limestone• Weathers yellow-brown, pitted, & honeycombed• Fossililerous

BRYAN COUNTY AREABRYAN COUNTY AREA

PawPaw Sandstone – McNutt Limestones

40 to 45 million years

The PawPaw Sandstone and McNutt Limestone are found in the Bokchito Formation of the Cretaceous Period.

PawPaw Sandstone allows water to seep through.

Under the PawPaw layer the McNutt Limestone holds the water. As a result the water backs ups through the sandstone to the surface. This provides a constant flow of water allowing for the growth of cattails on the side of the road.

BRYAN COUNTY AREABRYAN COUNTY AREA

SOPER LIMESTONESoper limestone lies between the Weno and Denton Shale

BRYAN COUNTY AREABRYAN COUNTY AREA

Kiamichi Formation

• Dark gray to black fissile shales interbedded in upper parts with thin beds of yellow-gray, fossilferous limestones forming the “shell beds” composed of abundant textgryphae navia.

• Thickness of layer: 30-40 feet• Oldest rock formation in the Cretaceous Period seen on Day

1. The fact that we found this Kiamichi Formation is a testimony to the amount of erosion that has taken place over the past 65 million years in Bryan County.

JOHNSTON COUNTY AREAJOHNSTON COUNTY AREA

Antlers Sandstone•White to yellow-brown•Ferruginous•Crossbedded•Non fossililerous•Line- to medium-grained sandstone•Poorly cemented•Friable pack sand: Interbeds of gray to black to purple • Ferruginous clay•Found in the Trinity Group of the Cretaceous Period•Unique Characteristics – Used by the Cardinal Glass Company

Cardinal Glass Sand Quarry

Woodford Shale• From the Mississippian-

Divonian Period (MDsw)• 360-408 million years old• Formed from water

particles settling and cementing together in deeper ocean areas

• Varied in color: light & dark gray, yellow, rusty

• Indicator for oil and natural gas

• Phosphate nodules present

Granitic Gneiss

•Medium to fine-grained

•Pervasive metamorphic textures

Ordovician Dolomite•This rock was found in the Cool Creek McKenzie Hill Formation.

•Approximate age • 505 – 438 million years.

•Environment of deposition • Deep ocean.

•It is non-clastic.

•It is composed of mineral magnesium instead of pure calcium carbonate, therefore it does not react to hyrdrochloric acid as dramatically as other limestone.

•This picture was taken at the Blue River Hunting and Fishing area.

Grandodiorite

• Precambrian

•Medium-grained gray : hornblende-biotite

Tishomingo Granite

About 1.3 billion years old

Used for the ground floors of the state capitol in Oklahoma City

West Spring Creek Limestone

• Tombstone Topography• Limestone: tan to gray• Chert nodules scattered

throughout formation• Ordovician Period (Ow), 438-

505 million years old• Mostly sea during that time• Lower Zone (224ft)• South limb of the West

Spring Creek Anticline

Butterly Dolomite

• Oldest member of the upper Arbuckle Group

• Located at the Ordovician/Cambrian boundary

• Pink/gray

• Medium to coarse grained sandy dolomite

• Contains milky quartz

Kindblade Formation/West Spring Creek Formation

• Tectonic breccia in the Kindblade• The breccia is found in the Ordovician period

Collins Ranch Conglomerate

South on I35 to first turnout, at the entrance-I35-marker 29, north end west side-wet turnout

Graben and syncline, Conglomerate pebbles and cobbles ranging in age from West Spring Creek to Reagan Sandstone, deposited into a graben

The Conglomerate is from the Pennsylvania period 320-286 million years ago

West Spring Creek Formation/Collins Ranch

Conglomerate

• Fault line for the north boundary of the Graben runs north of the road to the sign

West Spring Creek Formation• Marker 25 ft. below

top of Kindblade Limestone, one side of marker Kindblade Limestone [OK], one side is West Spring Creek Limestone [OW]

• Ordovician 438-505 million yrs.

• Gray, fine grained thick bedded

• Quartzose Sandstone marks the base of the West Spring Creek

North limb of the West Spring Creek Anticline

Kindblade Formation

• Ordovician Period, (Ok)

• 438-505 million years ago

• Mostly sea at that time

Royer Dolomite

• Cambrian Period (Cry), only sample• 505-545 million years old• Mostly sea at that time• Pink to gray in color• Massive Dolomite

Stratigraphic Sequence of

Rocks Observed this

Week.

Time Period Rock Name Environment of Deposition

Cretaceous Dexter Sandstone Shallow ocean

Bennington Limestone Deep ocean

PawPaw Sandstone Shallow ocean

McNutt Limestone Deep ocean

Soper Limestone Deep ocean

Caddo Formation Limestone & Shale Deep ocean

Kiamichi Formation Limestone & Shale Deep ocean

Antlers Sandstone Shallow ocean

Pennsylvanian Collings Ranch Conglomerate River

Mississippian Woodford Shale Deep ocean

Ordovician Keel Limestone Deep ocean

Sylvan Shale Deep ocean

Viola Group Limestone Deep ocean

Joins Group Limestone Deep ocean

West Spring Creek Form. Limestone Deep ocean

Kindblade Form. Limestone Deep ocean

Cool Creek Form. Limestone Deep ocean

McKenzie Hill Form. Limestone Deep ocean

Butterly Dolomite

Cambrian Royer Dolomite

Precambrian Granitic Gneiss

Tishomingo Granite

Troy Granite

Granodiorite