Marker Logo HMdb.org THE HISTORICAL
MARKER DATABASE
“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
Hastings in Dakota County, Minnesota — The American Midwest (Upper Plains)
 

Geology of the Dakota County Region

 
 
Geology of the Dakota County Region Marker image. Click for full size.
By Keith L, May 1, 2011
1. Geology of the Dakota County Region Marker
Inscription. Hasting lies just south and East of the last glaciation. About 20,000 years ago a lobe of ice, called the Superior lobe, advanced from the Lake Superior basin and crossed the ancient bedrock valley of the Mississippi River between St. Paul and Hastings. There it filled the valley with ice and sediment (silt, sand, gravel and boulders). Glacial ice trapped in the valley was then covered by more sediment as the ice lobe slowly receded. The melting lobe then deposited a large amount of sediment along its edge creating a swath of hills of which a portion curves around the Twin Cities on the south and west. This deposit of glacial sediment is called the St. Croix moraine. Meltwater streams flowed out from the Superior lobe, breached the moraine, and built a broad outwash plain of sand and gravel. This outwash deposit buried the Mississippi River valley south of the moraine as far as Hastings.

About 16,000 years ago another lobe of ice, the Des Moines lobe, advanced from the northwest through central Minnesota and eventually extended as far south as Des Moines, Iowa. Locally, meltwater from its eastern margin drained eastward and carved a river valley to the Mississippi River at the present site of Hastings. The modern Vermillion River is but a shrunken remnant of that stream.

Ice blocks buried within the St. Croix moraine
Geology of the Dakota County Region Marker image. Click for full size.
By Keith L, May 1, 2011
2. Geology of the Dakota County Region Marker
and filling the ancient bedrock valley of the Mississippi were insulated by sediment and melted very slowly. Eventually, their melting collapsed the moraine and re-established the Mississippi River valley for drainage. As the glacial lobes continued to recede, large volumes of meltwater flowed through the Mississippi again, forming numerous terraces and re-exposing the bedrock valley. When the influx of glacial meltwater ended, the volume of water in the Mississippi decreased greatly to what we see today.

Erected by the Geological Society of Minnesota in partnership with the Minnesota Department of Transportation and the Minnesota Geological Survey 1998
 
Erected 1998 by the Geological Society of Minnesota in partnership with the Minnesota Department of Transportation and the Minnesota Geological Survey.
 
Location. 44° 44.148′ N, 92° 51.474′ W. Marker is in Hastings, Minnesota, in Dakota County. Marker can be reached from 11th Street West near Forest Street. Click for map. Marker is in Roadside Park (along Minnesota Highway 55, mile west of U.S. Highway 61). Marker is at or near this postal address: 510 11th Street West, Hastings MN 55033, United States of America.
 
Other nearby markers. At least 8 other markers are within walking distance of this marker. Roadside Park Veterans Memorial (within shouting
Mississippi River at Hastings image. Click for full size.
By Keith L, May 1, 2011
3. Mississippi River at Hastings
U.S. Highway 61 Bridge
distance of this marker); Going with the Flow (approx. 0.7 miles away); Hastings Spiral Bridge (approx. 0.7 miles away); Downtown Develops (approx. mile away); American Legion Veterans Memorial (approx. mile away); Spiral Bridge (approx. mile away); Mississippi (approx. 0.8 miles away); Veterans Memorial Levee (approx. 0.8 miles away). Click for a list of all markers in Hastings.
 
Also see . . .  Geology of Minnesota. Wikipedia entry. (Submitted on May 7, 2011.) 
 
Categories. Waterways & Vessels
 
 
Credits. This page originally submitted on , by Keith L of Wisconsin Rapids, Wisconsin. This page has been viewed 556 times since then. Photos:   1, 2, 3. submitted on , by Keith L of Wisconsin Rapids, Wisconsin. This page was last revised on June 16, 2016.
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