1. Regional Groundwater Flowpath in Trans-Pecos, West Texas
Thandar Phyu
CE 394K-GIS in Water Resources
12/05/2000

2. Outline Introduction Isotopes Procedure Summary and Further Work
87Sr/86Sr
Procedure
Summary and Further Work
Acknowledgement

3. Location – Trans-Pecos

4. DEM Rustler Hills Wild Horse Flat Apache Mtn. Elevation Range
In meters
Apache Mtn.
Star Mtn

5. 87Sr/86Sr Used as a flowpath tracer Sr isotopes
no significant fractionation during mineral-water interaction
87Sr/86Sr reflects the Sr composition of mineral
Daughter product of 87Rb
Stable
higher 87Sr/86Sr with age

6. General Geology
Uliana, 2000

7. Procedure: 87Sr/86Sr Distribution
from (x,y) to decimal degrees
*.dbf – add event theme – create TIN from features
87Sr/86Sr Range

8. Convert To Grid 87Sr/86Sr Range 0.707-0.708 0.708-0.709 0.709-0.710
No data

9. 87Sr/86Sr Contour Lines
Exported as a *.shp from SURFER 7.0

10. Composite
No data

11. Comparison ArcView 3.2, Surfer 7.0 - Macromedia FreeHand 7.0

12. Conceptual Groundwater Flowpath
regional flowpath
Uliana, 2000

13. Summary and Further Work
Created Sr grid
Sr contours (SURFER 7.0)
Limitation – not enough data
Potentiometric Surface Map

14. Dept. of Geological Sciences
Acknowledgement
Mathew Uliana
Ph.D Candidate
Dept. of Geological Sciences
UT - Austin