Karst Landscapes The Interaction of Groundwater and Rock

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Karst LandscapesThe Interaction of Groundwater
and Rock

• Philip Reeder, Ph.D.
• Director, Environmental Science and Policy
  Program
• Department of Geography
• University of South Florida
• Tampa, Florida 33620

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Today I Will Discuss

• Geologic Aspects of Karst Landscapes
• Controlling Factors in Karst Landscape Formation
• Process and Form as Related to Karst Landscapes
• The Florida Karst
• The Floridan Aquifer
• Karst Springs
• Karst Environmental Hazards
• Understanding the Whole Picture of Florida Karst

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It all starts with the rock
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It all starts with the rockLimestone - chemical
vs. fossiliferous
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It all starts with the rockLimestone - chemical
vs. fossiliferous
There are also dolostones and evaporites, but
they are of limited extent in FL
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Geology of Florida
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Geology of Florida
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How the Weathering Processes Interact With the
Rock
Weathering Physical and chemical breakdown of
parent rock.
Short-Moderate
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How the Weathering Processes Interact With the
Rock
Weathering Physical and chemical breakdown of
parent rock.
Florida
Short-Moderate
The Chemical Weathering Type Solution The
Dissolution Process
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The Openings in the RockConcept of Karst
Porosity Permeability
Yorkshire Dales, England
Polk County, Florida
Yorkshire Dales, England
Floridan Aquifer Florida
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The Openings in the RockPorosity open space
Permeability connectivity
Yorkshire Dales, England
Polk County, Florida
Yorkshire Dales, England
Floridan Aquifer Florida
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Importance of the Nature of the Openings (Lines
of Weakness)Horizontal and Vertical Lines of
Weakness
Faults
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Importance of the Nature of the Openings (Lines
of Weakness)Horizontal and Vertical Lines of
Weakness
Faults
Lines of weakness exert control on pattern of
weathering
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A Key Controlling Factor IsPrimary vs. Secondary
Permeability
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Limestone PermeabilityThe Evolving End-Member
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Limestone PermeabilityThe Evolving End-Member
Links the rock (limestone) with a process
(weathering)
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The Dissolution ProcessAn Important Part of
the Continuum
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The Dissolution ProcessAn Important Part of
the Continuum
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The Dissolution ProcessAn Important Part of
the Continuum
Result equals dissolution along lines of weakness
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The Dissolution Process, Geologic Implications,
and Development and Evolution Of Karst Landscapes
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Implications of Subsurface vs. Surface Processes
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Karst AquifersProcess and Form
Vadose Zone
Phreatic Zone
Mixing Zone Corrosion
Dissolution concentrated along areas of highest
secondary permeability
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Karst LandscapesSurface and Subsurface
Relationships
Development of the subsurface plumbing network
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Spatial Perspective on KarstKarst Regions
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Spatial Perspective on KarstKarst Regions
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Spatial Perspective on KarstKarst Regions
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Spatial Perspective on KarstKarst Regions
Mantled Karst
Mantled Karst
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The Florida Platform
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Dynamic Nature of the Florida Platform Reflected
in the Geology of Florida
55 my Expanse of Geologic Time
Mix of Exposed and Mantled Karst Landscapes
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Geology Also Influenced the Floridan Aquifer
System
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The Floridan Aquifer
Fractured limestone mantled by surficial sand
deposits in some locations has created an
outstanding physical environment for the
formation of a large, well integrated aquifer
system.
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Karst Spring as Part of the Floridan Aquifer
System
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Karst Springs in Florida
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1st and Second Magnitude Springs in Florida
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The coming together of all of these occurrences
and processes produced the Florida Karst that we
see today
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Environmental Hazards---Karst Landforms
FEMA
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Environmental Hazards---Karst Landforms
FEMA
Groundwater Contamination
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Environmental Hazards---Karst Landforms
FEMA
Groundwater Contamination
Sinkholes
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Karst Hazards
Sinkhole Collapse
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Karst Hazards
Sinkhole Collapse
Sinkhole Flooding
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Karst Hazards
Sinkhole Collapse
Sinkhole Flooding
Karst Groundwater Contamination
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Karst Groundwater Contamination
Point and Non-Point Source Pollution
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Karst Groundwater Contamination
Concentrated Recharge
Conduit flow
Point and Non-Point Source Pollution
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Karst Groundwater Contamination
Concentrated Recharge
Conduit flow
Point and Non-Point Source Pollution
Domestic Source
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Sinkhole Flooding
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Karst Hazards Sinkhole Collapse
Winter Park, FL
Crooked Lake, FL
Guatemala City
Tucson, AZ ----Karst??
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Sinkhole Formation/Collapse
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Sinkhole Formation/Collapse
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Types of Sinkholes
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Subsidence Sinkhole
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Gradually Subsiding Solution Sinkhole
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Cover Collapse Sinkhole
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Buried Sinkhole
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Sinkhole Transition
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Conclusion Understanding Process and Form Leads
to.
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Understanding the Whole Picture