Carbonate Sedimentation in Ferruginous Lakes
Location
CSU Ballroom
Start Date
20-4-2015 2:00 PM
End Date
20-4-2015 3:30 PM
Student's Major
Chemistry and Geology
Student's College
Science, Engineering and Technology
Mentor's Name
Chad Wittkop
Mentor's Email Address
chad.wittkop@mnsu.edu
Mentor's Department
Chemistry and Geology
Mentor's College
Science, Engineering and Technology
Description
Ferruginous lakes provide a window through which geologists can study the geochemistry and biogeochemistry of Earth’s oceans prior to oxygenation by photosynthetic life. A lake is considered ferruginous if it has permanently anoxic deep waters and high iron concentrations. By studying the sediments of these lakes, it is possible to understand the development of microbialites that thrived when vast quantities of iron were deposited within Earth’s oceans. Two sites were selected for detailed analysis; Lake Malawi, Africa (MAL) and Otter Lake, Michigan (OL). Sediment core samples were obtained from the LacCore Facility based on iron carbonate (siderite) concentrations. X-ray Diffractometer (XRD) data are used to compare siderite compositions and X-ray fluorescence spectrometer (XRF) data are used to analyze elemental abundance. XRD and XRF data will be compared between OL and MAL, specifically comparing iron to aluminum (Fe:Al), iron to sulfur (Fe:S), and iron to phosphorous (Fe:P). Preliminary results show OL sediment are enriched in iron and manganese with generally low sulfur ratios. Continuing research will compare the results from OL analyses to that of MAL, which is known to contain siderite. If similarities are found this will indicate a common environment of formation between the lakes.
Carbonate Sedimentation in Ferruginous Lakes
CSU Ballroom
Ferruginous lakes provide a window through which geologists can study the geochemistry and biogeochemistry of Earth’s oceans prior to oxygenation by photosynthetic life. A lake is considered ferruginous if it has permanently anoxic deep waters and high iron concentrations. By studying the sediments of these lakes, it is possible to understand the development of microbialites that thrived when vast quantities of iron were deposited within Earth’s oceans. Two sites were selected for detailed analysis; Lake Malawi, Africa (MAL) and Otter Lake, Michigan (OL). Sediment core samples were obtained from the LacCore Facility based on iron carbonate (siderite) concentrations. X-ray Diffractometer (XRD) data are used to compare siderite compositions and X-ray fluorescence spectrometer (XRF) data are used to analyze elemental abundance. XRD and XRF data will be compared between OL and MAL, specifically comparing iron to aluminum (Fe:Al), iron to sulfur (Fe:S), and iron to phosphorous (Fe:P). Preliminary results show OL sediment are enriched in iron and manganese with generally low sulfur ratios. Continuing research will compare the results from OL analyses to that of MAL, which is known to contain siderite. If similarities are found this will indicate a common environment of formation between the lakes.
Recommended Citation
Torgeson, Joshua. "Carbonate Sedimentation in Ferruginous Lakes." Undergraduate Research Symposium, Mankato, MN, April 20, 2015.
https://cornerstone.lib.mnsu.edu/urs/2015/poster_session_B/23
