Karst -- Brief explanation of karst in Minnesota with diagrams (PDF document)
Cliff view -- Photo from a high elevation cave entrance. This cave was abandoned and the valley floor eroded as the landscape developed.
Speleothems -- Diagrams illustrating main forms of speleothems.
Speleothems -- Representative examples of stalagmites and stalactites.
Speleothems -- Representative examples of stalagmites and flowstone.
Multi-level cave -- Caves can form major passages on more than a single level. (karst is 3-dimensional)
Circular cave opening -- This circular cave opening is at the elevation of the cliff view picture. It's circular form indicates that it was created below the water table (phreatic origin). It is now abandoned and far above the current water table.
Sinkhole -- Typical sinkhole in a field.
Spring -- Water emerging from the base of a limestone bluff.
Stratigraphy -- Diagram showing stratigraphy of geologic unit in southeastern Minnesota. Caves and karst features are found in the carbonate units. (From MGS IC-6)
Speleothem ages -- Histogram showing U/Th disequilibrium age dates for speleothem samples from Minnesota and surrounding states. Width of columns are proportional to 1std statistical error.
Extent of glaciations -- Diagram showing the general maximum extent of glacial ice in North America.
Dates -- Diagram showing typical sampling sites and age ranges for speleothem U/Th disequilibrium dates.
Karst Stratigraphy -- Diagram showing how karst features such as caves and springs fit stratigraphically into a profile of the modern landscape.
Unless otherwise specified, photos and diagrams are credited to Richard Lively, Minnesota Geological Survey