The Philip M. Smith Graduate Research
Grant for Cave and Karst Research
2017
Grants
Samantha Feist ($2,000)
M.S. Candidate
School of Geography and Earth Science
McMaster University
Understanding sediment pathways in Hidden River Cave, Kentucky
Abstract - Examining sediment
transport in cave systems is difficult due to the complex nature of
karst systems, and it is not as well understood as surficial systems.
Cave sedimentology studies explore sediment transport and deposition
within cave systems. The objectives of this study are to better
understand sediment transport in karst cave systems by examining the
sedimentological record in Hidden River Cave in Horse Cave, Kentucky.
Hidden River Cave is an active cave system recovering from
contamination, providing a unique opportunity in the sediment record to
understand past sedimentation in the system. Additionally, current
research has uncovered microplastics, “plastic particles less than 5mm
in diameter”1 in surficial sediment samples from Hidden River Cave.
Further exploring the extent of microplastic contamination combined
with exploring the sediment record in the cave will allow for better
understanding of sediment transport in Kentucky cave systems and others
in similar karst landscapes.
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Robert J. Scharping ($3,000)
Ph.D. Student
Department of Cell Biology, Microbiology, and Molecular Biology
University of South Florida
Impacts of groundwater extraction on a
karst aquifer ecosystem and the use of ecological surrogacy for the
management of underwater caves
Abstract- Karst springs in
Florida support important surface ecosystems and provide valuable
services to humans. Spring water is sourced from underlying aquifers,
which support their own taxonomically rich microbial communities.
Microbial communities are particularly sensitive to environmental
disturbance and may therefore be useful indicators of aquifer ecosystem
condition. One type of disturbance occurring naturally in karst
aquifers is spring flow reversal, which brings surface water directly
into dissolution conduits. This natural phenomenon has yet to be
recorded as a result of human activity, but it may be happening at
Sulphur Springs, Tampa, FL, due to groundwater extraction and drawdown
of the local water table. We will deploy acoustic Doppler velocimeters
and water quality multiprobes in the Sulphur Springs karst conduit to
characterize the hydrological and physical profiles of this site. We
will also analyze water nutrient profiles spectrophotometrically and
characterize the groundwater biological community through molecular
methods. We will simultaneously study the same ecological parameters at
a pristine site, Crab Creek Spring, as a reference. Resource managers
of the City of Tampa will work with us to experimentally manipulate the
activity of municipal pumps at Sulphur Springs, which will alter the
flow within the conduit and potentially induce spring reversals. This
research will identify if spring reversals at Sulphur Springs are
caused by groundwater extraction, and what impacts hydrological
condition has on aquifer ecology. We will also identify the ecological
factors that should be managed for the conservation of karst spring
ecosystems in Florida and around the world.
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Natasha Sekhon ($2,000)
Ph.D. Student
Department of Geological Sciences
University of Texas at Austin
Validating near-entrance cave deposits as a high-resolution sub-annual paleotemperature proxy in New Mexico
Abstract - The geochemistry of
speleothems (cave deposits) are used to reconstruct past terrestrial
climate (i.e., rainfall amount, moisture source, vegetation) on annual
(high-resolution) or centennial (low-resolution) time-scales, have been
commonly studied from deep parts of caves. Recent studies of
speleothems from the traditionally overlooked near-entrance cave zones
(Webster et al., 2007) and shallow caves (Flohr et al., 2017) have
displayed the potential to study climate variability on a seasonal
timescale from these locations. Speleothem scientists have long avoided
the near-entrance cave zones and shallow caves because of concerns
regarding evaporation, kinetic isotope effects and biological activity.
A recent cave monitoring and speleothem calcite study (Feng et al.,
2014) from a small, well-ventilated, near-entrance cave zone (Westcave)
in central Texas shows temperature of surface air as the primary
control of calcite growth on a seasonal time scale. I propose to couple
modern cave monitoring, stable isotope (δ18O) and trace element (Mg/Ca
and Sr/Ca) analysis in a shallow cave to test the potential of
recording seasonality of temperature in speleothems. The focus of the
study is a shallow cave from New Mexico in the southwestern United
States similar to the Westcave setting of being well ventilated with
near-atmospheric CO2 concentrations and temperatures. The added
motivation to study southwestern United States is that it is a moisture
limited and drought-prone region, which is poorly studied for severity
of pre-instrumental droughts. The results from the study will have
implications for reconstructing high-resolution terrestrial
paleoclimate records to study seasonality in temperature in
drought-prone regions using speleothems.
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Hali Steinmann ($1,600)
M.S. Student
Department of Geography and Geology
Western Kentucky University
A geomorphic approach to understanding
karstification in the late‐Mississippian Pennington Formation, Savage
Gulf State Natural Area, Tennessee
Abstract - Karst processes
drive landscape evolution on the Cumberland Plateau, a physiographic
province spanning from northern Alabama and Georgia through Tennessee
into southeastern Kentucky. Situated near the crown of the plateau’s
stratigraphic sequence is the Pennington Formation, a heterogeneous
geologic unit that contains intermittent soluble rock layers such as
limestone and dolostone, along with varying amounts of shale,
siltstone, and sandstone. This research will take a geomorphological
approach with the goal of understanding solutional processes and
structural and lithologic controls on drainage in the Pennington
Formation in Tennessee’s Savage Gulf State Natural Area. The research
questions are: 1) what are the major controls on speleogenesis in the
Pennington Formation?, 2) how might the presence of soluble rocks in
this unit influence the overall karstification and denudation of the
Cumberland Plateau?, and 3) How can morphometric indices be applied to
cave survey data in order to distinguish between cave types and
interpret the effects of speleogenetic processes? The proposed research
will consist of geologic mapping and a karst feature inventory of the
Pennington Formation, a detailed survey of Pennington caves,
fluorescent dye tracer tests and chemical analysis of the hydrologic
system, morphometric analysis of cave survey data, and spatial analysis
using a GIS. Karstification of the Pennington Formation has
implications not only for geomorphology, but also for local ecology and
biodiversity, water quality, and land management.
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Barbara E. Wortham ($2,400)
Ph.D. Candidate
Department of Earth and Environmental Sciences
University of California, Davis
Reconstructing paleo-linkages between central California’s hydroclimate and global climate change
Abstract - Prolonged drought
over several years severely impacted California’s water resources,
indicating the need for a better understanding of how global climate
can affect California’s precipitation patterns. I propose to monitor
the evolution of surface precipitation geochemistry in response to
cave-related processes by measuring environmental surface conditions
above and within two Sierran foothill caves. The monitoring project
will allow for a greater understanding of how individual storms and
seasons impact the isotopic and physical parameters of the cave system
and will lead to a framework to be used in interpreting speleothem
based paleoclimate proxies. Cave monitoring is intrinsically linked to
the longer research goal, which is to develop and investigate the
feasibility of using speleothem fluid inclusion stable isotope and
noble gas compositions to assess quantitative changes in California
temperature and precipitation. Results from this work will include
seasonal variability in the stable isotopes in precipitation and drip
water in these locations, how individual storms impact those values,
how sensitive noble gas concentrations in dripwater are to changes in
cave air temperature, and how in cave systematics relate to
precipitated calcite. The proposed project is of great societal
significance as it will lead to a better understanding of California
hydroclimate and the link to global climate change.
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last updated or validated on January 26, 2019