Field Trip #3: Paleozoic Rocks II Cretaceous Stratigraphy of Central Texas

Field Trip #3: Paleozoic Rocks II

Cretaceous Stratigraphy of Central Texas

420K, 2006, Trip 3 – Paleozoic Rocks II

SATURDAY, March 4 SUNDAY, March 5 Ben’s Lab Crossy’s Lab 1 2 3 4 5 6 7 8 9 10 11 12

AL AWAMI; AHMED BENSCH; CATY LAVONNE FISHER; FRANK J. FRANCIS; LUKE KENNETH GREENE; LAUREN ELAINE PAPE; JAMES RUSSELL PINKSTON; DANIEL PATRICK RANDALL; BLAKE ANDREW RAWLINGS; COREY BROOKS STRYK; COURTNEY RENEE TURPIN; SARAH ASHLEY WALKER; ISABELLE NEWTON

1 2 3 4 5 6 7 8 9 10 11 12

ALBUTAIRI; FAHAD EMAD A CARLIN; JOSEPH PATRICK CORNELIUS; MELODY ANNE DUERSON; APRIL C. HOWARD; MELISSA ANN JOHNSON; BRANDON EVERETT KATERNDAHL; TIFFANY ANNE MOOTE; ERIC PAUL OCHOA; CARLOS EDUARDO RUSSO; MATT STEPHEN SCHEY; BJORN THOMAS WHITE; PHILLIP KYLE

Thomas’ Lab (Ryan) Ryan’s Lab (Thomas) 13 14 15 16 17 18 19 20 21 22 23 24 25 26

AHMED; SUMIYYAH COLLINS; ANA CRISTINA DLUBAC; KATHERINE ISIS DOROBEK; RUSSELL EDWARD GARBER; JOSHUA MICHAEL HERON; BRETANI REBECCA HEWLETT; ALICIA CHRISTINE KWONG; CALVIN KA-FEI LEE; PATRICIA LIN LLADO; LESLIE ELISABETH MATHIAS; WHITNEY DANIELLE NIKMANESH; PARNIA WICKMAN; TERRANCE JOSEPH WILSON; ALEXANDER COALE

13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

BEHRMAN; DEREK LAINE CHATFIELD; TOMMY LOYD COLEMAN; JOSEPH MACDONALD DE LEON; RYAN JOSEPH DICKERSON; TYLER ANDREW FLY; STERLING HARPER IV FREYTAG; DALE ROSS PICKELL; MICHAEL JOHN STACKHOUSE; STANLEY B. STANLEY; BLAIR AVANT STRONG; BRYAN JORDAN THOMPSON; JEFFREY ALAN TREVINO; RICHARD JAMES TURNER; ANDREW VAVOURAKIS; CONSTANTINE J

------------------------------------------------------------------------------------------------------------ Extra Saturday Extra Sunday 27 BAITIS; ELKE ELISE 28 SKELTON; CHRISTINA M. 28 29 30

CHRISTIANSON; PERRY A. AL-JOHAR; MISHAL MANSOUR KING; WILLIAM PRENTICE

29 30

SWANSON; TRAVIS ERIC KNOWLES; JENNIFER NICOLLE


• Location

• Geology

• Assignment / Methods

• Reminders

Text: Manual, p. 267-278; Compton, p. 166-171; 182-184; 242-243.

Location Hamilton Creek

road cut near Max Starke Dam

Stop 1

Stop 2

(E. McBride)

(E. McBride)

(Luis Garcia)

Location

Creek near Stop 2

Geology

Geology

Bastrop

N

5 miles

Paleozoic Sedimentary Rocks

Pennsylvanian – Smithwick Shale

Ordovician – Honeycut Formation of Ellenburger Group

(Manual, p. 272)

Paleozoic Events

Geology

• Flooding by Shallow Seas

• Uplift Ouachita Mts (Penn)

• Faulting (Penn)

• Erosion of Ouachitas (P-J)

• sabkha

• evaporites

• karst

• natural gas - subsurface

Ellenburger Group

Geology

(nps.gov)

Geology

Guidebook of the Geology of Travis County

• marine

• high sediment supply

• turbidites

Smithwick Shale

Geology

(E. McBride)


• Location

• Geology


• Reminders


Assignment / Methods

1) Smithwick Shale Paleocurrent and Deformation Features

• measure and plot the orientation of:

1) joints

2) faults

3) sandstone dikes

4) fossil wood fragments

5) current ripples and solemarks

• water-saturated sediment

• excess pore pressure

sandstone feeder bed

sandstone dike

(416M)


clastic dikes and joints


(E. McBride) (E. McBride)

solemarks

416M

groove castsAssignment / Methods

flute casts

(416M)

(416M)


• plot features in 4 rings

• show # of measurements

• show bi-directional trends


2) Honeycut Formation Checklist

road cut near Max Starke Dam(E. McBride)

limestone

vs

dolomite


Dolomite - Thin Section

Dolomite - SEM

(Soil Science Society of America)

(Soil Science Society of America)

stylolites

vs

stromatolites


(Luis Garcia)

(Earth and Ocean Sciences at UBC)

fault breccia

vs

solution collapse breccia


(Compton, p. 183)

• solution collapse breccia – filled cave

• fault breccia – repeated crushing / cementation

soft-sediment deformation

vs

brittle deformation


(Compton, p. 243)

• faults break more resistant layers only

• mottled textures in shear zone

teepee structure

and

geopetal structure


(Matt Campbell)

Geopetal – Thin Section


• Location

• Geology


• Reminders


Reminders

• Water

• Lunch

• Clipboard

• Colored Pencils

• Ruler & Protractor

• Extra Paper

• Brunton

• Rock Hammer

• HCl Acid

• Hand Lens

• Field Notebook

• Lab Manual




• Paleogeography and Sea Level

• Stratigraphy

http://www4.nau.edu/geology/master.html?http://www4.nau.edu/geology/

Late Cretaceous Paleogeography

Paleogeography and Sea Level


• Paleogeography and Sea Level

• Stratigraphy

(Manual, p. 272)

Stratigraphy

• relatively flat-lying

• retreating escarpment

(Duex and Lock, Univ. LA)

Stratigraphy

• resistant and non-resistant limestone

(www.cretaceousfossils.com)

Glen Rose Limestone Stairsteps

Hensell Sand Badlands

• hard (pure) and soft (clay-rich)

• shallow subtidal and supratidal

• sand, conglomerate, paleosols

• terrestrial environment

(www.cretaceousfossils.com)

Stratigraphy

Oyster-rich Del Rio Clay

• pure limestone and dolomite

• chert-rich

• carbonaceous clay

• pyrite – anoxic lagoon

Edwards Limestone “Swiss Cheese”

Stratigraphy

Documents

Field Trip #3: Paleozoic Rocks II Cretaceous Stratigraphy of Central Texas