Presentation is loading. Please wait.

Presentation is loading. Please wait.

Data Exploration: Characterization of the Groundwater resources of the Leona Aquifer Lloyd Hemphill December 3, 2002.

Similar presentations


Presentation on theme: "Data Exploration: Characterization of the Groundwater resources of the Leona Aquifer Lloyd Hemphill December 3, 2002."— Presentation transcript:

1 Data Exploration: Characterization of the Groundwater resources of the Leona Aquifer Lloyd Hemphill December 3, 2002

2 Introduction Why should shallow alluvial aquifers be studied? Convenient source of groundwater.. Abundant worldwide. Recharge areas for deeper aquifers. Easily contaminated. The Pleistocene age Leona Formation is a prime example.

3 Geologic Background

4 Goals Use GIS to: Gather data in a useable format. Assess extent of existing data in space and time. Examine the spatial changes in water quality in the Leona Aquifer. Create a map to aid in locating wells. Compare water quality in the Leona Aquifer to surrounding aquifers.

5 Data Included in Geodatabase National Elevation Dataset DEM for San Marcos Basin. USGS HUC for San Marcos Basin. River reach data. TX-DOT.DGN of Highways for Caldwell Co. TWDB well data: Well locations, water levels, and water quality.

6 Topography of the Leona Formation Northwest to Southeast slope: 0.002 or 0.12 degrees. Very Flat! Inverted topography.

7 Wells in Caldwell County, TX

8 Nitrate in the Leona Aquifer (1946) MCL is 44.27 mg/l as Nitrate Note the Nitrate hotspot near Lockhart

9 Nitrate in Wilcox Group Wells (1946) Note the Nitrate hotspot near Lockhart.

10 Chloride in the Leona Aquifer (1946) Secondary MCL is 250 mg/l.

11 Chloride Concentration Changes in Lockhart, TX

12 Water Table Elevation in the Leona Aquifer (1964) Hydraulic gradient is very small: 0.0027 (0.15 degrees ). Groundwater flow is to the southwest and toward the margins of the formation.

13 Water Level Change in the Leona Aquifer

14 Future Work Add digital geologic map to geodatabase. Compare water level change and precipitation data. Examine land use to determine possible sources of NO3 and Cl.

15 Questions?


Download ppt "Data Exploration: Characterization of the Groundwater resources of the Leona Aquifer Lloyd Hemphill December 3, 2002."

Similar presentations


Ads by Google