The Analysis of Cave Dripwaters and Cave Calcite Deposits with GIS Resources

Central Texas Cave Project

Constituents of Concern Include:

Central Texas Cave Project Constituents of Concern Include: Driprates of Cave Dripwaters Pic of Dripping stalagtite

Central Texas Cave Project Constituents of Concern Include: Calcite Growth

Central Texas Cave Project Constituents of Concern Include: Dripwater Geochemistry

Central Texas Cave Project Constituents of Concern Include: Dripwater Geochemistry  pH  Conductivity  Major Ions  Isotopic Compositions (Oxygen, Deuterium, Carbon)  Alkalinity

What affects the geochemistry of these waters? What affects the rates of calcite growth? What affects the geochemistry of these waters? What affects the rates of calcite growth?

Project Objectives 1) Precipitation 2) Overlying Soils 3) Land Cover Use GIS to determine:

Study Area  Caverns of Sonora  Natural Bridge Caverns  Innerspace Caverns

Project Objectives 1) Precipitation 2) Overlying Soils 3) Land Cover Use GIS to determine:

Texas Average Annual Precipitation Source: Texas Water Development Board

Central Texas Average Annual Precipitation Source: Texas Water Development Board

Central Texas Average Annual Precipitation  Caverns of Sonora lies within inches per year Source: Texas Water Development Board

Central Texas Average Annual Precipitation  Caverns of Sonora lies within inches per year  Natural Bridge Caverns and Innerspace Caverns lie within inches per year Source: Texas Water Development Board

Are differences in precipitation evident in cave driprates?

Driprates Caverns of Sonora has average driprates much smaller than Innerspace Caverns and Natural Bridge Caverns

Are differences in precipitation evident in cave calcite growth?

Calcite Precipitation Caverns of Sonora isn’t growing much calcite!

Project Objectives 1) Precipitation 2) Overlying Soils 3) Land Cover Use GIS to determine:

Are differences in soil type above each cave evident in cave dripwater geochemistry?

Source: Statsgo Soil Database

Caverns of Sonora- MUID TX544 Natural Bridge Caverns- MUID TX105 Innerspace Caverns- MUID TX153 Source: Statsgo Soil Database

Natural Bridge Caverns Innerspace Caverns Caverns Of Sonora Source: Statsgo Soil Database

Project Objectives 1) Precipitation 2) Overlying Soils 3) Land Cover Use GIS to determine:

How do differences in land cover change the geochemistry of the cave dripwaters?

Source: NLCD 1992 Land Cover Dataset

Caverns of Sonora Innerspace Caverns Natural Bridge Caverns Source: NLCD 1992 Land Cover Dataset

Conclusions  GIS is a useful tool for delineating spatial heterogeneity over land surfaces  GIS is useful in bringing together many different parameters in which relationships may exist

Future Work  Determine other factors (fractures, bedrock, evapotranspiration) that may be influencing the different chemical constituents that are analyzed in the caves  Use tracking analyst to determine driprate and geochemical response to rainfall events