Abstracts with Programs - Geological Society of America

SESSION NO. 19
19-2 BTH 20 Doughty, Travis M. [218754]
TRACE METAL CHEMISTRY AND MINERALOGY OF SEDIMENTS HOSTED IN CAVES OF
THE SPRINGFIELD (MO) PLATEAU: A LINK TO SUBTERRANEAN BIODIVERSITY?
DOUGHTY, Travis M., Natural Sciences, Northwest Missouri State University, 800 University
Dr, Maryville, MO 64468, s507452@nwmissouri.edu and JOHNSON, Aaron W., Natural
Sciences, Northwest Missouri State University, 800 University Drive, Maryville, MO 64468
We used X-ray fluorescence (XRF) and X-ray diffraction (XRD) to compare the heavy metal
chemistry and mineralogy of sediments accumulating in caves in rural and urban areas to the
chemistry and mineralogy of sediments from a control cave in a relatively undisturbed watershed
in the Springfield (MO) Plateau. Sediment from the control cave exhibited the smallest peak
sizes for Zn and Mn and a moderately-sized Pb peak. Sediment from the rural caves exhibited
larger peaks of Zn and Mn and a smaller Pb peak. Sediment from the urban cave had the largest
Zn, Mn and Pb peaks. X-ray diffraction indicated that all samples contained calcite and quartz,
which is unsurprising since the caves are hosted in the Burlington Limestone, which is noted for
abundant chert nodules. However, minor mineralogy varied widely, and included traces of clay
minerals, metal oxides, metal hydroxides, garnet, and complex aluminum-sulfates. Additionally
the carbon content of some samples was high enough to trigger an elemental carbon peak that
was not consistent with graphite or diamond. These data indicate that trace amounts of base and
heavy metals present in sediment are not hosted in sulfides or other primary phases. Instead,
these metals likely occur as cations adsorbed onto the surfaces of clay minerals or as metal
hydroxides such as wulfingite, an amphoteric zinc hydroxide mineral that was indicated by XRD
analysis. Metals hosted in these phases may be liberated by dilute acid solutions. This finding
has important implications for the health of troglobitic species, and may explain the apparent
relationship between species presence and low metal concentrations in cave sediments outlined
in an earlier pilot study. The presence of metals as hydroxides or adsorbed phases in sediments
could prove harmful to troglobites that spend a significant portion of their life cycle in sediment
(e.g. isopods), especially those species that digest sediment. The acidic digestive tract may
increase metal concentrations in primary consumers, potentially reducing fecundity. In addition,
secondary consumers may suffer from bioaccumulation as they prey upon species with higher
tissue metal concentrations.
19-3 BTH 21 Norton, M.S. [218357]
MODELING SOIL EROSION WITHIN THE MILL CREEK WATERSHED, YOUNGSTOWN, OHIO
NORTON, M.S. and MATTHEUS, C.R., Geological and Environmental Sciences, Youngstown
State University, One University Plaza, Youngstown, OH 44555, msnorton@student.ysu.edu
Mill Creek Park, established in 1896, is one of the largest metro-parks in the US, providing a
variety of outdoor activities to the city of Youngstown, Ohio, and its surrounding areas. Popular
attractions within the park include a number of man-made ponds and lakes, which have rapidly
silted in since their construction, forcing several sediment-excavation projects. An investigation
is underway to elucidate information from lake deposits to help develop an erosion model for
contributing watersheds.
A preliminary erosion model based on the Universal Soil Loss Equation was established for
a small subset of the Mill Creek watershed. This model incorporates existing datasets on soil
characteristics, topography, and climate in an effort to constrain a parameter for land cover;
information on sediment yield was used to solve for this unconstrained factor. Lily Pond is a 3-acre
catch basin that receives sediment from surrounding forested hillslopes, typical terrain and landcover
types within the park. A 1974 excavation of the pond provided a baseline for assessing
subsequent sediment sequestration, quantified from detailed bathymetric surveys and cores.
Sediment-yield calculations were compared to the watershed-erosion model and provided a
refined land-cover factor for future modeling within the park.
Current research is now underway to provide additional model-parameter constraints
utilizing similar methodologies. Differences in sediment yield between watersheds of similar
size, topography, and soil characteristics provide clues regarding the influence of land-cover
types, which vary tremendously across the region. The Indian Run watershed, for example, is
characterized by 21% urban land cover and 23% agricultural land cover whereas the Bears
Den watershed is characterized by 66% and 0%, respectively. Improving individual parameters
using comparison studies that incorporate empirical data on sediment yield are critical to the
development of an erosion model that is regionally applicable.
SESSION NO. 20, 1:30 PM
Thursday, 2 May 2013
T19. Hydrogeologic Investigations for Improved
Assessment of Water Availability and Use in the
Glaciated United States (Posters)
Schneider Hall, Courtyard
20-1 BTH 22 Wyman, Davina A. [218128]
THE EFFECTS OF ROAD SALT ON ASYLUM LAKE GEOCHEMISTRY
WYMAN, Davina A., Geosciences Department, Western Michigan University, 1187 Rood
Hall, Kalamazoo, MI 49008, davina.a.wyman@wmich.edu and KORETSKY, Carla M.,
Geosciences Department, Western Michigan University, 1903 W Michigan Ave, Kalamazoo,
MI 49008-5241
Asylum Lake is a 19.8 ha kettle lake located in Kalamazoo, MI near three major roadways, thus
it is expected to receive runoff with significant concentrations of road salts in winter and spring.
Road salts contribute unreactive Cl-to surface and groundwaters, which can accumulate and
significantly increase water density. Typical lakes in Michigan experience turnover events in fall
and spring, during which water from the epilimnion is mixed with water from the hypolimnion. With
enough of an increase in water density, lake turnover events may be delayed or prevented (e.g.
Wetzel, 2001, Limnology). The objective of this study is to determine if road salts in Asylum Lake
are preventing turnover events and, if so, how this changes the lake geochemistry.
Lake water column samples have been collected monthly at the deepest point in the lake,
beginning in September 2012; sampling will continue for one year. In situ measurements of
dissolved oxygen (DO), conductivity, temperature, and pH are measured at .5 m intervals. Four
water samples per 1 m depth are collected at 1m intervals, filtered (.2 μM), and two are preserved
with HNO . Samples are immediately analyzed upon return to the lab for Fe 3 2+ , Mn2+ 3- + , PO , NH4 ,
4
26 2013 GSA Abstracts with Programs
alkalinity, and H S via colorimetry. Within one week of collection, samples are analyzed on an
2
ICP-OES for Ca2+ , Mg2+ , K + , and Na + . Within two weeks, samples are analyzed for Cl- on an ion
2- chromatograph and for SO via a turbidity technique.
4
Data thus far shows Asylum Lake to be a eutrophic lake with anoxic benthic waters throughout
+ 2+ 3- summer and early fall. In the anoxic hypolimnion, there is a build-up of NH , Mn , PO4 , and H2S 4
to levels as high as 220, 40, 11, and 87 μM, respectively, but Fe2+ levels are always at or below
detection limits of 3.5 μM. Concentrations of Cl-reach up to 180ppm. Conductivity increases with
depth in the summer and fall but becomes nearly constant during one sampling event in early
winter. On this date, temperature and DO also vary much less with depth, which suggests that fall
turnover occurred, but was significantly delayed.
20-2 BTH 23 Lotimer, Leslea [218488]
THE NATURE OF TILL AND DRUMLINS IN PETERBOROUGH AND THE IMPLICATIONS FOR
DEVELOPING A COMMUNITY GROUNDWATER SUPPLY
LOTIMER, Leslea, McMaster University, Hamilton, ON L8S4L8, lotimelp@mcmaster.ca
In the Peterborough area of Ontario, Canada, there is a well-documented and extensive drumlin
field. While the origin of the drumlins is widely debated despite many years of study, one aspect
remains certain; drumlins and till have significant implications for groundwater movement and
public water supply. The late Wisconsin Northern Till, deposited by the Laurentide Ice Sheet,
is found in the area of the Peterborough drumlin field, and is considered to be a deformation
till up to 65 meters thick. The till overlies proglacial and glaciolacustrine sediments and shows
considerable textural and thickness variability within the drumlin field. Coarse-grained interbeds
are common within the till and allow it to function as a ‘leaky aquitard’ as opposed to most till
units which are considered to be regional aquitards. The presence of significant coarse-grained
interbeds within the till produces groundwater flow pathways that are not easy to predict and
which can have significant implications for contaminant transport and groundwater supply. A First
Nations community located within the Peterborough Drumlin field has been attempting to find a
more sustainable groundwater supply in the drumlizined terrain. Currently, homes are supplied
by private wells. Options are being considered for improving individual wells or developing a
communal water supply. A recent field program involved drilling a fully cored and geophysically
logged borehole through till on the flanks of a large drumlin as well as the construction of a
well by air rotary. The extracted core consists primarily of sand-rich till with interbeds of sand
and gravel. Correlation of data between the two recently drilled wells and lithological and
hydrogeological data obtained from local water well records allows analysis of the till stratigraphy
within this portion of the drumlin field. This till stratigraphy provides a foundation for understanding
local groundwater movement and the potential for public water supply. This preliminary
interpretation of the local stratigraphy will guide further field work and provide the basis for
improving the supply of drinking water for the community.
20-3 BTH 24 Bunda, Jacob [218445]
QUALITY AND DYNAMICS OF THE MINK RIVER ESTUARY
BUNDA, Jacob, UW-River Falls, River Falls, WI 54022, jacob.bunda@my.uwrf.edu
The Mink River Estuary (MRE) is a freshwater environment connecting with Rowley’s Bay on
the northeast side of Door County, Wisconsin. Spring complexes originating in the surrounding
wetland exchange mineral enriched groundwater with the water of Lake Michigan within the
estuary. Seiche motion originating in the body of Lake Michigan is pronounced in the calm
water of the MRE and encourages mixing of spring and Lake Michigan waters. A gradational
geochemical pattern exists throughout the estuary from the spring to its mouth and is influenced
by the lake’s water level. Water level data show a direct relationship between Lake Michigan
water level and the water level within the MRE. In-situ water quality data reveal the composition of
spring and estuary water. Temperature data is included and show variation over time in different
parts of the estuary and northwest spring complex. Linear regression of the MRE’s chemical
gradient over time reveals change in the variation of the chemical pattern along the estuary axis.
The state of the estuary is dependent on its quality and quantity of water, monitoring of water
levels and other parameters in the MRE is helpful for understanding how the environment may be
affected by groundwater influences and Lake Michigan water level. This project builds on studies
done by the Wisconsin Geological & Natural History Survey (WGNHS).
20-4 BTH 25 Nagelkirk, Ryan L. [218198]
PREDICTING THE IMPACTS OF CLIMATE CHANGE ON AGRICULTURAL YIELDS AND WATER
RESOURCES IN THE MAUMEE RIVER WATERSHED
NAGELKIRK, Ryan L. 1 , KENDALL, Anthony D. 2 , BASSO, Bruno2 , and HYNDMAN, Dave3 ,
(1) Geological Sciences, Michigan State University, 288 Farm Lane, East Lansing, MI 48824,
nagelki4@msu.edu, (2) Department of Geological Sciences, Michigan State University, 206
Natural Sciences Bldg, Michigan State University, East Lansing, MI 48824, (3) Geological
Sciences, Michigan State University, 206 Natural Science, East Lansing, MI 48824
Climate change will likely have considerable effects on agriculture in the Midwestern United
States. Under current climate projections, end-of-century temperatures rise by approximately
4°C, while precipitation stays relatively unchanged despite a potential increase in heavy rainfall
events. These trends have already been observed over the last century: rising temperatures have
extended the growing season two days per decade and heavy rainfall events have become twice
as common. In an effort to understand the likely effects of climate change on agriculture, maize
and soybean yields in the Maumee River Watershed were simulated using the Systems Approach
to Land Use Sustainability (SALUS) crop model. SALUS calculates daily crop growth in response
to changing climate, soil, and management conditions. We test the hypotheses that 1) despite any
positive effects of CO2 fertilization and allowing for higher yielding varieties, longer and warmer
growing seasons will lead to excessive water- and heat-stress, lowering yields under current
management practices, and 2) that double-cropping maize and soybeans successively in the
same season to offset these losses may become feasible if sufficient late-season soil moisture
is made available. Outputs of daily Leaf Area Index (LAI) and root mass from a range of SALUS
models are then distributed spatially to drive regional hydrologic simulations using the Integrated
Landscape Hydrology Model (ILHM). These coupled simulations demonstrate the response of
streamflow and groundwater levels to different management strategies.