480 likes | 817 Views
WHAT IS KARST?. SLOVENIA. ITALY. TWO DOMINANT TYPES OF KARST LANDSCAPE?. Determined by the origin or “genesis” of the waters doing the solution. TWO DOMINANT TYPES OF KARST LANDSCAPE?.
E N D
WHAT IS KARST? SLOVENIA ITALY
TWO DOMINANT TYPES OF KARST LANDSCAPE? Determined by the origin or “genesis” of the waters doing the solution
TWO DOMINANT TYPES OF KARST LANDSCAPE? 1. Autogenic: Waters originate as precipitation directly over the region of Karst. Auto = “self” genesis
TWO DOMINANT TYPES OF KARST LANDSCAPE? 1. Autogenic: Waters originate as precipitation directly over the region of Karst……. Auto = “self” genesis. 2. Allogenic: Waters originate in some region other than the Karst and then flow over the limestone – generally as a river….. Allo = Spanish “Allí” = “there” … i.e. Not here!
WHAT ARE THE TYPICAL FEATURES OF AN AUTOGENIC KARST LANDSCAPE? Central and South Florida
Sand Limestone
H20 + CO2 = H2CO3 Sand Limestone
H20 + CO2 = H2CO3 Sand Infiltration Capillary Water Limestone
H20 + CO2 = H2CO3 Sand Infiltration Capillary Water CO2concentration in soil 10x that of atmosphere! Limestone
H20 + CO2 = H2CO3 Sand Infiltration Capillary Water Limestone Highly acid water low CaCO3 content. Aggressive! Picks out layers (bedding planes) and vertical joints for erosion.
H20 + CO2 = H2CO3 Sand Infiltration Capillary Water Limestone Bedding planes and vertical joints enlarged by erosion.
H20 + CO2 = H2CO3 Sand Infiltration Capillary Water Groundwater table Limestone
H20 + CO2 = H2CO3 Sand Infiltration Capillary Water Groundwater table rises - more water, greater soil mass Limestone
Period of heavy rains such as tropical storms, hurricanes or stationary fronts H20 + CO2 = H2CO3 Sand Infiltration Capillary Water Heavy, saturated soil collapses into underground cavern system, causing surface sinkhole. Limestone
During protracted drought the water table drops, leaving some caverns near the surface empty of water. Sand Limestone
Roof of cave collapses when no longer supported by water, and soil falls into sinkhole Sand Limestone
Most local streams flow into, but not out of lakes. They leave the region underground via the cave system. Sand Limestone
WHAT ARE THE TYPICAL FEATURES OF AN ALLOGENIC KARST LANDSCAPE? North Central Florida
100’ LIMESTONE South Gainesville North Gainesville
150’ CLAY 100’ LIMESTONE South Gainesville North Gainesville
SAND 150’ CLAY 100’ LIMESTONE South Gainesville North Gainesville
SAND High Infiltration Rates
SAND High Infiltration Rates CLAY Low Infiltration Rates
SAND High Infiltration Rates Excess Water fills pores – “perched” or “surficial” water table CLAY Low Infiltration Rates
SAND High Infiltration Rates Excess Water fills pores – “perched” or “surficial” water table CLAY Low Infiltration Rates Free or Gravitational Water moves horizontally along the geologic junction.
Water table intersects land surface as “springs” and “seeps”, the origin of most creeks in Gainesville
BOULEWARE SPRINGS HOGTOWN CREEK GLEN SPRINGS
SAND 150’ CLAY 100’ LIMESTONE Payne’s Prairie South Gainesville North Gainesville
SAND 150’ CLAY 100’ LIMESTONE Biven’s Arm Kanapaha Prairie South Gainesville North Gainesville
O’Leno and River Rise State Parks SAND 150’ CLAY 100’ LIMESTONE South Gainesville North Gainesville
O’LENO STATE PARK RIVER RISE STATE PARK