GILMER-THESIS-2013

187 Pages·2013·5.45 MB·English

GEOARCHAEOLOGICAL INVESTIGATIONS OF SITE FORMATION PROCESSES

IN AREA 15 AT THE GAULT SITE, BELL COUNTY, TEXAS

Presented to the Graduate Council of
Texas State University-San Marcos
in Partial Fulfillment
of the Requirements

for the Degree

Master of ARTS

by

Anastasia Gilmer, B.S.

San Marcos, Texas
August 2013
GEOARCHAEOLOGICAL INVESTIGATIONS OF SITE FORMATION PROCESSES

IN AREA 15 AT THE GAULT SITE, BELL COUNTY, TEXAS

Committee Members Approved:

C. Britt Bousman, Chair

Michael B. Collins

Charles Frederick
Approved:

J. Michael Willoughby
Dean of the Graduate College
COPYRIGHT

by

Anastasia Gilmer

2013
FAIR USE AND AUTHOR’S PERMISSION STATEMENT
Fair Use
This work is protected by the Copyright Laws of the United States (Public Law 94-553,
section 107). Consistent with fair use as defined in the Copyright Laws, brief quotations
from this material are allowed with proper acknowledgment. Use of this material for
financial gain without the author’s express written permission is not allowed.

Duplication Permission
As the copyright holder of this work I, Anastasia Gilmer, authorize duplication of this
work, in whole or in part, for educational or scholarly purposes only.
DEDICATION

To my parents. Thank you for your love, support, and encouragement.
ACKNOWLEDGEMENTS

Particular thanks to my committee members for their insights, encouragement,
and time: Dr. Bousman for his support and always making time for me when I needed to
talk, Dr. Collins for his guidance and wisdom, and Dr. Frederick for his advice and
unending patience while I was at his lab.
My sincerest appreciation goes to the Gault School of Archaeological Research
for providing me with the opportunity to conduct this research. Clark Wernecke, Nancy
Littlefield, and Steve Howard were always willing to answer my questions and be out at
the site when I needed to be there.
I would like to thank the Center for Archaeological Studies at Texas State and
especially David Yelacic for helping me with the magnetic susceptibility equipment.
Analyses were conducted at Charles Fredericks’ laboratory. The generous
support provided by himself and Brittney Gregory is appreciated.
The preliminary research results of Sergio Ayala, Jennifer Gandy, and Nick
Rodriguez, were discussed here and provided invaluable archaeological data to
supplement this geoarchaeological study. Also, a spreadsheet created by Paul Lehman
was used to calculate texture as well as the mean and standard deviation for each sample.
Finally, I would like to thank Robert Lassen for his comments on an earlier draft.
This manuscript was submitted on April 29, 2013.

vi
TABLE OF CONTENTS

Page
ACKNOWLEDGEMENTS ............................................................................................... vi
LIST OF TABLES ...............................................................................................................x
LIST OF FIGURES ........................................................................................................... xi
CHAPTER
1. INTRODUCTION .............................................................................................1

Objectives and Justification of Research .....................................................1
Archaeological Investigations at the Gault Site ..........................................3
Geoarchaeological Investigations at the Gault Site ....................................6
The Cultural Components at the Gault Site .................................................6
OSL Dating the Gault site ................................................................8
Brief Outline.................................................................................................9

2. REDEFINING CLOVIS ..................................................................................11

Subsistence and Mobility ...........................................................................13
Traditional View as Hunting Specialists .......................................13
Growing View as Generalized Hunters and Gatherers .................14
Fauna at Gault ...............................................................................16
Clovis Lithic Technology ...........................................................................16
Clovis Lithics .................................................................................16
Lithic Insights from Gault ..............................................................17
The Clovis-First Paradigm ........................................................................19
Pre-Clovis Occupations .................................................................19
Why the Slow Rate of Acceptance? ................................................21

3. ENVIRONMENTAL SETTING ....................................................................24

Site Location ..............................................................................................24
Modern Environment .................................................................................30
Climate ...........................................................................................30
vii
Hydrology ......................................................................................32
Flora ..............................................................................................33
Fauna .............................................................................................34
Relationship between site setting and cultural history at Gault ....36
Bedrock Geology of the Balcones Escarpment and Edwards Plateau ......37
The Cretaceous System ..................................................................37
Geology of the Balcones Escarpment ............................................38
Geology of the Edward’s Plateau ..................................................38
Soils of the Edwards Plateau .....................................................................39
Soils at the Gault and Friedkin Sites .............................................40
Late Quaternary Environmental History and Landscape Evolution in
Central Texas .......................................................................................40
Stable Isotopic Analyses ................................................................43
Pollen Analyses ..............................................................................46
Faunal Analyses .............................................................................48
Geomorphic Analyses ....................................................................50
Archaeological Site Preservation and Formation Processes on the
Edward’s Plateau.................................................................................52
Cultural Remains versus the Original Cultural Component .........53
Geomorphic Processes...................................................................53
Pedoturbation ................................................................................54
Landscape Evolution and Formation Processes within Buttermilk Creek
Valley ...................................................................................................57
Landscape Evolution and Alluvial History ....................................57
Site Formation Processes ..............................................................59
Summary ....................................................................................................64

4. METHODS ......................................................................................................65

Field Descriptions and Profile Drawings ..................................................65
Sample Collection ......................................................................................66
Particle-Size Analysis ................................................................................66
Organic Carbon and Organic Matter Content ..........................................72
Calcium Carbonate Content ......................................................................75
Magnetic Susceptibility ..............................................................................78

5. RESULTS ........................................................................................................80
General comments .....................................................................................80
Column A ...................................................................................................83
Texture Analysis .............................................................................83
Calcium Carbonate ........................................................................86
Organic Carbon and Organic Matter ............................................86
Magnetic Susceptibility ..................................................................87
Field Observations .........................................................................87
Artifacts ..........................................................................................87
Column B ...................................................................................................88
viii
Texture Analysis .............................................................................88
Calcium Carbonate ........................................................................90
Organic Carbon and Organic Matter ............................................90
Magnetic Susceptibility ..................................................................90
Artifacts ..........................................................................................90
Column C ...................................................................................................90
Texture Analysis .............................................................................92
Calcium Carbonate ........................................................................92
Organic Carbon and Organic Matter ............................................92
Magnetic Susceptibility ..................................................................93
Field Observations .........................................................................93
Column D ...................................................................................................93
Texture Analysis .............................................................................93
Calcium Carbonate ........................................................................93
Organic Carbon and Organic Matter ............................................95
Magnetic Susceptibility ..................................................................95
Field Observations .........................................................................95
Artifacts ..........................................................................................95

6. DISCUSSION ..................................................................................................96

Area 15 .......................................................................................................96
Sedimentary Processes...................................................................96
Pedogenic Processes ....................................................................103
Post-Depositional Processes .......................................................108
Buttermilk Creek Valley ...........................................................................111
Sedimentary and Pedogenic Processes ........................................111
Post-Depositional Processes .......................................................113
Central Texas ...........................................................................................115
Where to Look for “Old Dirt” .................................................................116
Possible Directions of Future Research ..................................................118
Photo-Sieving ...............................................................................118
Size-Sorting ..................................................................................118
OSL dating ...................................................................................118

7. CONCLUSIONS............................................................................................120

APPENDIX A: GEOLOGIC PROFILES AND DESCRIPTIONS .................................123

APPENDIX B: RESULTING DATA FROM ANALYSES ...........................................137

REFERENCES CITED ....................................................................................................155

ix
LIST OF TABLES

Table Page
1. Legend for map unit symbols in Figure 13 ..................................................................42
2. Simplified characterization of site types and settings in Central Texas ......................54
3. Multiple-aliquot OSL ages on quartz grains ................................................................81
4. Summary of the changes in the hydrologic regime at Area 15 ..................................101
5. The relationships between the cultural horizons, soil horizons, and stratigraphic units
in Columns A, B, and C .............................................................................................105
6. Comparison between the stratigraphic units at Fort Hood, Buttermilk Creek, and Area
15................................................................................................................................112
7. Comparison between the stratigraphy in Area 8 and Area 15 ...................................113

x