HR: 0800h
AN: ED31B-1209 [Abstracts]
TI: Investigation of a playa lake bed using geophysical electrical methods
AU: * Herrmenn, M
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Gurrola, H
EM: harold.gurrola@ttu.edu
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: William, R
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Montalvo, R
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Horton, S
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Homberg, J
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Allen, T
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Bribiesca, E
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Lindsey, C
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Anderson, H
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Seshadri, S
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Manns, S
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Hassan, A
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AU: Loren, C
ED31B-1209
AF: Texas Tech, Dept. of Geoscinces
Texas Tech University, Lubbock, TX 79409
United States
AB:
The 2005 undergraduate applied geophysical class of Texas Tech University conducted a geophysical survey of a playa lake
approximately 10 miles northwest of Lubbock Texas. The playa lake is primarily used as grazing land for two llamas and a hand
full of sheep, and has been recently used as a dump for broken down sheds and barrels. Our goal was to model the subsurface
of the transition from the playa to plains geology and investigate the possible contamination, of the soil and the data, by
the metal dumped at the surface.
We conducted our survey with and EM31 and homemade D.C. resistivity and SP equipment that allowed students to grasp the
theories more clearly. SP readings were collected using clay pots constructed from terracotta pots and copper tubing
purchased at the local hardware store and voltage measurements collected with handle held multi-meters. D.C. resistivity data
were collected in a dipole-dipole array using 20 nine volt batteries connected in series with a large enough variable
resistor and amp meter to regulate steady current flow. A multi meter was used to collect voltage readings. Wenner array
data were collected using a home-made multi-filament cable connected switch box to allow a central user to regulate current
and take voltage reading.
A map of conductivity produced from a 10 m of EM31 reading show that conductivity anomalies mirror topography. The SP
profiles show high values in the playa lake that drop off as we move from the clay rich lake bed to normal grassland.
Analysis of both the Dipole-Dipole and Wenner array data support a model with 3 flat layers increasing in resistivity with
depth. It appears that these remain flat passing beneath the playa and the playa is eroded into these layers.
DE: 0800 EDUCATION
DE: 0810 Post-secondary education
DE: 0825 Teaching methods
DE: 0840 Evaluation and assessment
DE: 0845 Instructional tools
SC: Education and Human Resources [ED]
MN: Fall Meeting 2005