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Lakes, Rivers, Streams, and Groundwater Principal Watershed Components Aquifers/ groundwater Lakes Rivers/Streams Swamps/Wetlands Soils Hydrologic Connections The Florida Example Geologic Time Line Precambian 4.5 Bya to 500 Mya (Earth formation, cooling, oceans, atmosphere, life, oxygen) Paleozoic 500 Mya to 248 Mya Mesozoic 248 Mya to 65 Mya Cenozoic 65 Mya to present Approximately 250 million years ago Breakup of Pangaea Late Triassic, early Jurassic - 250 Mya Rifting phase 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 Carbonate Deposition Marine Calcium and Magnesium Carbonate CaCO3 MgCO3 Between about 150 Mya and 25 Mya Florida platform was a flooded, submarine plateau dominated by carbonate deposition CaCO3 FL platform The Florida Platform Raised above earth’s crust Dominated by carbonates Formed over millions of years Gently sloping Cenozoic Era Paleocene Eocene 66-58 MYA 58-37 MYA Oligocene Miocene 37-24 MYA 24-5.3 MYA Pliocene 5.3-1.8 Pliestocene 1.8 MY – 10KYA carbonates Before Miocene Late Oligocene-Early Miocene Paleocene Eocene 66-58 MYA 58-37 MYA Oligocene Miocene 37-24 MYA 24-5.3 MYA Pliocene 5.3-1.8 Pliestocene 1.8 MY – 10KYA Georgia Channel Suwannee Current Late Oligocene-Early Miocene Paleocene Eocene 66-58 MYA 58-37 MYA Oligocene Miocene 37-24 MYA 24-5.3 MYA Pliocene 5.3-1.8 Pliestocene 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 Late Oligocene-Early Miocene Paleocene Eocene 66-58 MYA 58-37 MYA Oligocene Miocene 37-24 MYA 24-5.3 MYA Pliocene 5.3-1.8 Pliestocene 1.8 MY – 10KYA sediments Georgia Channel Suwannee Current Siliciclastic Deposition silici- clastic- refers to a chemical composition rich in silicate material 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 Sands sands, silts, clays, rock 25 to 5 Mya Limestone Miocene deposits are siliciclastic: sands, silts, clays, rocks Miocene sediments are marine sediments Megalodon #MG1 Locality: Hawthorne Formation, South Carolina Age:Miocene Size: 6 inches exactly Virtually flawless museum grade specimen. Perfect serrations, black and gray mottling Price: $785.00 SOLD In Gainesville, Miocene clays tend to be fairly thick and, in many cases, close to the surface Alfred A. Ring Park 1801 NW 23rd Boulevard—parking at Elks Lodge 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 Sediment Thickness Alachua County Thin or absent 30 – 200 ft sandy Miocene 30 – 200 ft clayey > 200 ft thick Jurassic To Miocene Thinning Miocene Sediments The thickness of the Miocene sediments has A direct bearing on the formation of springs and sinkholes Carbonate Dissolution Acid (H+) dissolves calcium carbonate Miocene Siliciclastics Marine Carbonates Limestone Cavities Directly underlies Miocene deposits Miocene Siliciclastics Sinkholes 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 Sinkhole Lakes Lakes are hydrologically connected to each other And with the underlying aquifer system Springs Springs form best when the overlying clay layer is thin. 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 Hydrologic Connections