Lakes, Rivers, Streams, and Groundwater

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Lakes, Rivers, Streams, and Groundwater
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Principal Watershed Components
Aquifers/ groundwater
Lakes Rivers/Streams Swamps/Wetlands Soils
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Hydrologic Connections
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The Florida Example
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Geologic Time Line
Precambian 4.5 Bya to 500 Mya Paleozoic 500
Mya to 248 Mya Mesozoic 248 Mya to 65
Mya Cenozoic 65 Mya to present
(Earth formation, cooling, oceans, atmosphere,
life, oxygen)
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Approximately 250 million years ago
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Breakup of Pangaea
Late Triassic, early Jurassic
- 250 Mya
Rifting phase
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Approximately 150 - 200 million years ago
Late Jurassic
High Sea Levels
Flooded, stable platform for marine sedimentation
FL platform/plateau
For the next several million years the platform
was dominated by carbonate deposition
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Carbonate Deposition
Marine Calcium and Magnesium Carbonate
CaCO3 MgCO3
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Between about 150 Mya and 25 Mya
Florida platform was a flooded, submarine plateau
dominated by carbonate deposition
CaCO3
FL platform
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The Florida Platform
Raised above earths crust Dominated by
carbonates Formed over millions of years Gently
sloping
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Cenozoic Era
Paleocene Eocene Oligocene Miocene
Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA
5.3-1.8 1.8 MY 10KYA
carbonates
Before Miocene
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Late Oligocene-Early Miocene
Paleocene Eocene Oligocene Miocene
Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA
5.3-1.8 1.8 MY 10KYA
Georgia Channel
Suwannee Current
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Late Oligocene-Early Miocene
Paleocene Eocene Oligocene Miocene
Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA
5.3-1.8 1.8 MY 10KYA

• Events
• Lifting of the Florida Platform
• Lowering of Sea Levels, diversion of the Gulf
  Stream,
• interruption of Suwannee Current
• Rejuvenation of Appalachians, increased sediment
  load
• Filling of Georgia Channel
• Rising sea levels, lack of Suwannee Current
• Continental depositional influence on Fl. platform

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Late Oligocene-Early Miocene
Paleocene Eocene Oligocene Miocene
Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA
5.3-1.8 1.8 MY 10KYA
sediments
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Siliciclastic Deposition
silici- refers to a chemical composition
rich in silicate material
clastic- refers to the origin of the particles as
clasts, products or fragments of silicate
rocks.
Typical earth materials Silicon-based sands,
silts, clays, rocks, rock fragments
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Sands
25 to 5 Mya
sands, silts, clays, rock
Limestone
Miocene deposits are siliciclastic sands, silts,
clays, rocks
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Miocene sediments are marine sediments
Megalodon MG1Locality Hawthorne Formation,
South CarolinaAgeMioceneSize 6 inches
exactlyVirtually flawless museum grade specimen.
Perfect serrations, black and gray
mottling Price 785.00 SOLD
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In Gainesville, Miocene clays tend to be fairly
thick and, in many cases, close to the surface
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Alfred A. Ring Park
1801 NW 23rd Boulevardparking at Elks Lodge
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The thickness of and depth to Miocene sediments
varies
0-500 ft thick in the North-central part of state
Up to 40 phosphorus
Also contains uranium
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Sediment Thickness
Alachua County
Thin or absent
Miocene
30 200 ft sandy
30 200 ft clayey
Jurassic To Miocene
gt 200 ft thick
Thinning Miocene Sediments
The thickness of the Miocene sediments has A
direct bearing on the formation of springs and
sinkholes
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Carbonate Dissolution
Acid (H) dissolves calcium carbonate
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Miocene Siliciclastics
Marine Carbonates
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Limestone Cavities
Directly underlies Miocene deposits
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Miocene Siliciclastics
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Sinkholes
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Solution (sinkhole) lakes
The most common origin of lake formation in
Florida
Limestone bedrock is dissolved by acids
Land subsidence into dissolved limestone cavity
creates depressions filled with water
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Sinkhole Lakes
Lakes are hydrologically connected to each
other And with the underlying aquifer system
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Springs
Springs form best when the overlying clay layer
is thin.
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Calcareous streams
originate from springs
colder temperatures
clear water
rich in calcium and phosphorus
Direct hydrologic connection with the carbonate
aquifer
Santa Fe Ichetucknee Weeki Wachee
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Hydrologic Connections
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