Browsing by Subject "Cambrian"
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Item Ahrensfeld Creek and Borson Northeast Dye Trace Report 2007-2010 Winona County, MN(2017) Green, Jeffrey A; Alexander Jr., E. Calvin; Alexander, Scott C; Luhmann, Andrew J; Runkel, Anthony C; Peters, Andrew JSoutheastern Minnesota’s karst lands support numerous trout streams. These trout streams are formed by springs discharging from Paleozoic bedrock. Dye tracing has been the tool of choice for mapping the springsheds (karst groundwater basins) that feed these springs. Previous work was focused on the Galena limestone karst. In order to accelerate springshed mapping, a two-year study was funded by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR). Across southeastern Minnesota, numerous springs discharge from the Cambrian St. Lawrence formation. The St. Lawrence is considered to be a confining unit under the Minnesota well code. A dye trace was initiated when a stream sink was discovered in the upper St. Lawrence Formation. The sampling points included springs, stream crossings, and a municipal well that may be at risk for surface contamination. Dye was recovered at one spring in less than two weeks and at two other springs in less than three weeks. This translates into travel times of 200-300 meters/day. The springs all discharge from the lower St. Lawrence Formation. The St. Lawrence contains beds of dolostone; the dye trace demonstrates that there is a karst conduit flow component in this formation. This is evidence that these springs are significantly more susceptible to degradation than previously thought.Item Altura Minnesota lagoon collapses(Proceedings of the First Multidisciplinary Conference on Sinkholes. Orlando, Florida 15-17 October 1984. "Sinkholes: Their Geology, Engineering and Environmental Impact. Edited by Barry F. Beck of the Florida Sinkhole Research Institute, University of Central Florida, Orlando. Page 311 - 318. Taylor & Francis, London, UK. Offprint, 1984-10-17) Book, Paul R; Alexander Jr., E. CalvinIn April 1976, a series of karst sinkholes opened in the holding lagoon of the Altura, Minnesota Waste Treatment Facility. This major failure was preceded by minor sinkhole formation during the construction of the facility in 1974. Subsequent detailed field mapping of the region around the community revealed at least 23 sinkholes not shown on existing maps. The distribution of the sinkholes as well as post-failure investigations of the lagoon indicate that catastrophic collapse is related to the presence of a thin, poorly indurated, jointed sandstone overlying a thick carbonate unit. The sandstone served to collect solutionally aggressive vadose water and to concentrate that water onto specific areas of the underlying carbonate. The resulting differential solution produced voids into which the overlying materials collapsed.Item Altura, MN Waste Treatment Lagoon Failures: A Hydrogeologic Study(1984-02) Book, Paul R; Alexander Jr., E. CalvinIn April 1976, a series of karat sinkholes opened in the holding lagoon of the Altura MN Waste Treatment Facility. Subsequent detailed field mapping of the region around the community revealed at least 22 sinkholes not shown on existing maps. The distribution of the sinkholes as well as post-failure investigations of the lagoon indicate that catastrophic collapse is related to the presence of a thin, poorly indurated, jointed sandstone overlying a thick carbonate unit. The sandstone served to collect solutionally aggressive vadose water and to concentrate that water onto specific areas of the underlying carbonate. The resulting differential solution produced voids into which the overlying materials collapsed. The disabled facility has been diverting partially treated effluent into a nearby dry run since the lagoon collapsed. A dye trace documented that the effluent after sinking underground reemerges from three local springs and then flows into a river which is a regional trout fishery. However, a second dye trace from the sinkhole in the lagoon failed to establish a connection to any local well or spring.Item Groundwater Tracing in the Duschee Creek Karst Basin in Southeast Minnesota(2017-06) Wheeler, Betty JItem REPORT on the 2012-2013 Traces Conducted on Bridge Creek Houston County, Mn(2014) Barry, John D; Green, Jeffrey AItem Report on the 2013 Dye Trace Conducted on Girl Scout Camp Creek Houston County, MN(2014) Barry, John D; Green, Jeffrey AItem South Branch Whitewater River Valley Dye Trace Report Elba/Altura, Winona County, Minnesota(2017-06-30) Ustipak, Kelsi R; Green, Jeffrey A; Wheeler, Betty J; Alexander Jr., E. Calvin; Rutelonis, J. Wes