Exam II.Kc
Describe the 6 main coastal regions in FL. JEREMY - WHAT SHOULD WE KEEP?
1. Northwest Barrier Chain (NW panhandle) - Apalachicola River: 1,359 m max. elevation: 50,500 km 2 basin area. Significant siliciclastic sediment supply to coast. Citronelle Formation and Miocene siliciclastic rich strata. Bathymetry shows evidence of large sediment depocenters at shelf break (~ 120 m) and on shelf. 2. Big Bend Marsh Coast (the armpit of FL) - The lack of ancient large streams flowing across peninsular Florida in the area of the modern marsh coast is also a factor explaining the dearth of quartz sands. Other rivers emanate from springs fed by the Floridan Aquifer and travel only a few kilometers across the coastal plain before reaching the Gulf of Mexico. Holocene sea level rise has flooded a low gradient, karstified, bare rock surface of the ancient carbonate bank where well cemented, shallow marine skeletal limestones of Eocene/Oligocene age are exposed. 3. West-Central Barrier Chain (west of Tampa) -The barrier inlet system on the west central peninsula of Florida has the most diverse morphology of any barrier system in the world. It extends for about 300 km and includes 29 barrier islands and 30 tidal inlets. Included are long, narrow, wave dominated barriers of both spit and upward shoaling origins and mixed energy drumstick barriers of a range of sizes and shapes. Spring tidal range is just under 1 m and mean annual wave height is about 25 cm at the shore. The coastal barrier system is one of mixed tidal and wave energy. Some individual barriers are indicative of more wave (e.g., Captiva Island) than tidal influence (e.g., Siesta Key). The morphology of the barriers is the result of the interplay between these coastal processes. Slight modifications to either tidal or wave parameters can cause a significant shift in the morphology of the barrier inlet system, especially along a low energy coast. The general condition is one of a sediment starved coast with virtually all Holocene terrigenous sediments having been supplied through reworking during the transgression of the past 7,000 years and continuing to the present. The Holocene sediment prism is thickest under the barriers and thins offshore, so that at depths of 5 to 6 m there is little or no quartz sand overlying the pre-Holocene. There is also a thinning shoreward with the marine Holocene pinching out at the mainland coast. The total Holocene sequence at any given location along this coast is typically less than 7 to 8 m and may be as little as 3 m. Once the islands became emergent, they were frequently overwashed until beach foredune ridges became sufficiently elevated to prevent this process. The islands where sediment was abundant built prograding ridge systems, whereas those in areas of little sediment were extended along shore and remained narrow 4. Ten Thousand Mangrove Coast (SW FL west of Everglades) - The southwest coast at the southern end of the west central barrier coast is dominated by mangroves. This coastal segment is tide dominated due to the broad, gently sloping continental shelf and the very low mean annual wave height (10 cm) coupled with the broadly embayed coastal configuration. The mangrove coast is can be divided into sections: (1) the northern portion, commonly called the Ten Thousand Islands, and (2) the southern portion, which is adjacent to the Everglades and lacks numerous discrete mangrove islands. Intertidal vermitid reefs provided the topographically high areas for mangrove colonization, which eventually led to the domination of the coast by mangrove islands. The combination of the presence of these islands and the mud accumulation that they foster has resulted in a 2 m thick progradational sequence during the very slowly rising sea level of the late Holocene. 5. Florida Keys - The Florida reef tract forms a thin belt of Holocene sediments and reefs between the Pleistocene Keys and the edge of the platform (18 m contour) to the east. Pleistocene Carbonates consist of: 1) the Key Largo Limestone (a fossilized (120 130 ka) Pleistocene coral reef forms the upper Keys), and 2) the lower Keys, composed of the Pleistocene Miami Oolite (preserved tidal bars). The upper surface of all Pleistocene limestones throughout the area, whether oolitic or coralline, is karstic and generally calcrete coated. The deposits were leached, cemented and coated with calcrete when sea level fell more than 100m between 120 and 100 ka. The modern keys consist of a hermatypic coral reef track that started formation ~8 kya. Wind and waves have a dominating influence on reef development and carbonate sand distribution. Aerial photos show many areas where fan like deposits of carbonate sand have spilled seaward through depressions between reefs. Hurricanes are the most likely cause of these fans. 6. FL East Coast Barrier Chain - The longest barrier island/tidal inlet system (550 km) of any state. The present east coast of Florida is dominated by Holocene quartz sand barrier islands significant areas, however, (e.g., Anastasia Island, Cape Canaveral) where carbonate rich Pleistocene strata (i.e., Anastasia Formation) outcrop or underlie coastal sands. receives long period swell, but not influenced as regularly by intense extratropical storms as are the Outer Banks, Long Island, and Cape Cod to the north. Broader shelf off the northeast Florida coast and Bahama Banks also provide protection. The relatively low frequency of high intensity storms (including hurricanes) coupled with a regional abundance of sand, both on the Florida coastal plain to the west and the submerged shelf to the east, have formed a relatively stable, barrier island chain.
What are the three main controls on Florida coastal geology (and coastal geology in general) emphasized by Dr. Jaeger?
1. Sediment supply: river vs. longshore drift vs. local 2. accommodation space: room to accumulate sediment 3. sediment dispersal energy: waves and tides
Cite two natural conditions that impact the frequency of sinkhole activity.
1. Water levels dropping/drought 2. Oxidation of Histosols (muck and peat soils)
Generally, how old are the barrier islands on the US East coast thought to be?
18,000 years
Where is the Apalachicola River's drainage basin?
20K miles2 in western Georgia, eastern Alabama, and central panhandle Florida
About how many lakes are in Florida?
30,000 that cover a little more than 3 million acres.
About how many first magnitude springs are in Florida?
33
How does first magnitude springs in FL compare with other places in the US?
33 out of 78
Which lake type is most common in FL?
70% of Florida lakes are seepage lakes
Where is the St. John's River's drainage basin and mouth?
9500 miles2 in NE Florida mouth above Jacksonville flows north
What is a typical age for these lakes (in general)?
<10,000 years old
What physical characteristic tends to control the tendency for Florida lakes to be monomictic or polymictic?
???? Depth?
Define and characterize eutrophic lakes.
A eutrophic water lake has high biological productivity. • Low water clarity, dense landward vegetation, nutrient rich, dense, less diverse aquatic population, high sedimentation
Old lakes in Florida?
A few Florida lakes are old and held water in the Pleistocene (Annie, Tulane, Sheelar, Camel). •They are relatively deep (>20 m). • Deeper lakes in Florida are warm monomictic (mix ~ January-March, stratify ~March-December)
What is Karst topography?
A landscape is shaped by dissolution of rock (particularly by groundwater)
What is the potentiometric surface?
A potentiometric surface is the imaginary plane where a given reservoir of fluid will "equalize out to" if allowed to flow. Groundwater separated from atmospheric pressure by relatively impermeable material is termed confined groundwater. When such zones are penetrated by wells, the water rises above the point at which it was first found because a confined aquifer is under pressure exceeding that of atmospheric pressure.
Define Perched water table:
A small (often ephemeral) zone of saturation elevated above the main water table
What is the purpose of aquifer storage and recovery?
ASR is capturing water when it is abundant, storing the water in the subsurface in brackish aquifers, and recovering the water when needed. ASR wells are used to store water in the ground and recover the stored water for drinking water supplies, irrigation, industrial needs, or ecosystem restoration projects.
What is peat?
Accumulation of organic materials, precursor to coal (if buried deep and long enough), used for horticulture and fuel
Define and characterize oligotrophic lakes.
An oligotrophic lake is a lake with low primary productivity, as a result of low nutrient content. • High water clarity, sparse landward vegetation, nutrient poor, sparse aquatic population, low sediments
What are the materials mined here in Florida?
Anhydrite Aragonite Calcite CO3-OH-apatite CO3-F-apatite Dolomite Gibbsite Goethite Gypsum Hematite K-feldspar K-Mica Kaolinite Opal (-A, -CT) Palygorskite/Sepiolite Pyrite Quartz Smectite: (Montmorillonite & Nontronite)
What is the largest river in Florida
Apalachicola
What are the 5 largest rivers in Florida?
Apalachicola Suwannee Choctwhatchee Escambia St. Johns
What is aquifer storage and recovery?
Aquifer storage and recovery (ASR) is the direct injection of surface water supplies such as potable water, reclaimed water (i.e. rainwater), or river water into an aquifer for later recovery and use.
Why do good aquifer strata (rock or sediment materials) need to be both porous and permeable?
Aquifer strata needs to be porous and permeable to let water in, store it, and move it.
What is an aquifer?
Aquifers is a term for a type of soil that can hold and transfer water.
What is an aquitard (or aquiclude)?
Aquitard/aquiclude is impermeable rock or strata that is a barrier to groundwater flow.
Define Zone of Saturation:
Area of the subsurface where pores spaces are completely filled with water
What is a barrier island?
Barrier Islands are type of island made up of long stretches of sand that are parallel to the mainland.
Where does Cody Escarpment occur?
Between the Gulf Coastal Lowlands and Northern Highlands
What conditions are necessary for karst formation?
Carbonic acid (dissolution of CO2 in water); areas where limestone (or gypsum, marble, etc.) is a dominant rock type at or near the surface; sufficient precipitation/humid climate; warm climate;
What is the boulder zone?
Cavernous zone of fractured dolomite
Where is Lake Okeechobee?
Center South Florida
Where is the Kissimmee River?
Central Florida
Where is the Apalachicola River?
Central Panhandle Florida
What is Fuller's earth?
Clay
Give one example of a geologic material that makes a good aquitard.
Clay, shale, and intrusive igneous rocks make good aquitards. Mostly Clay
Describe cover collapse sinkholes.
Clay-rich, cohesive overburdens can bridge limestone cavities --> changes in water table level (pumping effect) weakens the bridging overburden, resulting in collapse -->lack of support on falling water table--> -->upward pressure in the case of a rising water table
Ignoring weather-related geohazards (hurricane, lightning, etc.) which common geohazards (volcanoes, earthquakes, coastal flooding, river flooding, sinkhole activity pose significant threat in Florida?
Coastal flooding, river flooding, sinkhole activity
What areas of Florida have the highest occurrence of sinkholes?
Concentrated in north central/west central FL, along the Cody Escarpment/Gulf Coastal Plain and in west central FL (SW FL WMD)
Why isn't sinkhole activity randomly distributed around the state? Cite two natural (i.e. not anthropogenic)
Conditions that impact the frequency of sinkhole activity: • Water levels dropping/drought • oxidation of Histosols (muck and peat soils)
Describe cover-subsidence sinkholes.
Cover is mainly non-cohesive, permeable sand; developed by gradual subsidence; generally only a few feet in diameter and depth; generally remain small, cavities are filled as fast as they develop.
Which is in a more mature state of karst development, Cuba or Florida?
Cuba
Discuss stratification in FL lakes. Which lakes tend to stratify? Which do not?
Deep lakes tend to stratify. Shallow lakes tend to be wind mixed.
What has boulder zone been used for in S. Florida?
Deep well injection of treated sewage
How does depth to the Floridan Aquifer generally vary along the FL Peninsula?
Depth increases in south. The Floridan aquifer averages 1,000 feet thick, and freshwater can extend to a depth of 2,000 feet below land surface. Freshwater is thickest in the central portions of the state and rapidly thins toward the coast and the south.
What are three different methods of detection of void space in the subsurface?
Detection Methods: • Ground penetrating radar Depth dependent on materials (<1m up to 15m in rock/sed) • Resistivity surveying • Drilling • Seismic studies • Microgravity
What are some issues of concern related to groundwater resources in the Floridan aquifer?
Drawing down the aquifer ETC. (FILL IN!)
What are three different methods of detection of void space in the subsurface?
Drilling, ground penetrating radar (limited to depth can look dependent on materials), resistivity surveying (inexpensive)
What are the characteristics (age, lithology, confinement, etc.) of the Floridan aquifer?
Eocene limestone, Miocene clay
What is the character of the middle confining unit of the Floridan?
Eocene, part of Avon Park Formation, limestone
How do evaporation rates vary (or not) in Florida?
Evaporation rates increase down the peninsula from about 45"/yr in the NE to 54"/yr in the SW (which receives only 0-3"/yr rainfall in excess of evaporation)- Due to the decline in humidity, southern Florida appears to have increased evaporation and evapotranspiration (through vegetation).
Compare/contrast the sands along beaches on the Florida east coast north of the keys from that in the Keys. Explain the cause of any differences.
FL east coast siliciclastic from longshore transport; Keys localized carbonates
Over what timescale can significant change happen to a barrier island?
Feels like this should have a real number, but I'm not finding one. • Significant change can happen on a larger time scale as sea-level fluctuations occur, or wave action erosion.
To what extent is Florida a player in overall US petroleum production?
Florida is a Minor player in US petroleum production
What causes wave refraction?
Friction with the sea bed as waves approach the shore causes the wave front to become distorted or refracted as velocity is reduced
What are magotes?
Generally-isolated steep-sided residual hill composed of either limestone, marble, or dolomite. Mogotes are surrounded by nearly flat alluvial plains. The hills typically have a rounded, tower-like form. Several mogotes along a ridge are called pepinos.
Why was the Pleistocene an important time in the karstification of the Florida Platform?
Glaciation causing sea levels to drop
Why is understanding these characteristics important when considering matters of groundwater pollution?
Groundwater contamination and saltwater intrusion
Cite two ways in which human activity might affect sinkhole formation activity. Make specific reference to data presented in the Tihansky Paper.
Groundwater pumping and lowering of water table (and potentiometric surface). 1. Pumping for crop freeze protection, 2. Heavy pumping during dry months (March-May)
About how much of Florida's water input comes from groundwater inflow?
Groundwater=176 billion gallons/day
Where in Florida are the major recharge zones for the Floridan Aquifer?
Gulf Coastal Lowlands
How did sea level at the interglacial high stand (~150ka) compare to that of today?
Higher
What are the minerals that comprise titanium ores?
Ilmenite, Rutile, Leucoxene
About how many people are employed directly in FL mining? Indirectly?
In 2012 18,630 directly employed in mining, Another 62,270 employed in total (direct and indirect)
How might one interpret the potentiometric surface in an unconfined aquifer?
In an unconfined aquifer the water table is the top of the aquifer and therefore establishes the potentiometric surface.
Chemical reaction leading to karstification?
In the presence of limestone, carbonic acid dissolves the calcite: CaCO3 + CO2 + H2O <-> Ca++ + 2HCO3-
Give two examples of geologic materials that make good aquifers.
It is a layer of rock that has high porosity and permeability. Glacial till, sandy soils are common materials where aquifers develop. Other material are sandstones, conglomerates and fractured limestones.
Are all high porosity rocks permeable and low porosity rocks impermeable? Give examples to support your answer
It is assumed that soils or material with high porosity should also be permeable, but there are weird instances. Clay is porous but is least permeable, clay acts as an aquitard, preventing water to flow. Chalk is highly porous, unless it is squeezed, and the air pores are reduced.
How did sea level in the Pliocene at ~ 4Ma compare to that of today? Identify one Florida geographic/geologic feature associated with that time and shoreline?
It was much higher, as observed along the orangeburg scarp. Also, the sedimentary rocks have a marine record in these wave-cut scarps.
Where besides the Florida can one find karst topography?
Kentucky, Indiana, West Virginia, Illinois, Cuba, southeast Asia
What is Fuller's earth used for?
Kitty litter, oil absorbency, toilets.
Where is the Kissimmee River's mouth?
Lake Okeechobee
Describe solution or subsidence sinkholes.
Limestone is exposed at or near the surface --> covered by soil and insoluble materials as the depression forms; usually not large; bowl shaped (steepness often indicator of the rate of subsidence)
What causes longshore transport?
Longshore transport is the movement of sand and sediment parallel to the coastline and is caused by most waves reaching the shore at a small angle, and as each one arrives, it pushes water along the shore
Define and characterize mesotrophic lakes
Mesotrophic lakes are lakes with an intermediate level of productivity. • Medium water clarity, increasing landward vegetation, increasing nutrient, diverse and increasing aquatic population, increasing sediments
From what age deposits is Fuller's earth mined?
Miocene
From what age strata are these materials being extracted?
Miocene clastic sediments
What age and type of material forms the upper confining layer for the Floridan?
Miocene, Hawthorne Formation, limestone (The upper confining unit includes all lowpermeability late and middle Miocene beds (sequence of clastic sediments), where present, and locally includes lowpermeability postMiocene beds (Miller, 1986). It contains the intermediate aquifer system and Brunswick aquifer system, which locally interact with the Floridan and surficial aquifer systems.)
How did Florida's landmass compare at last glacial maximum to today (general description)?
More of Florida basement was subaerially exposed
Where is the St. John's River?
NE Florida
Was Florida the only place where concentrated phosphate deposition occurred at this time?
No, North Carolina too
What solid products are left behind from the chemical reaction leading to karstification?
None
What are the 5 water management districts in FL?
Northwest Suwannee Southwest South St Johns
What are some concerns with Lake Okeechobee?
Nutrification flooding water shortages nutrient release
What conditions allowed these economically extractable phosphate deposits to form?
Oxygen rich bottom waters, and organic poor sediment deposits. Seamounts are common landscapes to have phosphate deposits.
Define permeability.
Permeability is the ability a soil or surface has to allow water to infiltrate. a measure of a materials ability to transmit a fluid (in this case water)
In what materials (non place-value) is Florida a significant contributor on a national or global scale?
Phosphate and Fullers earth production (clay)
Define Spring:
Place where groundwater flows out onto the surface.
From what Florida geologic deposits are titanium ores mined?
Plio-Pleistocene beach ridges
When and how did heavy mineral deposits form?
Plio-Pleistocene beach ridges e.g., Trail Ridge
How do the porosity and permeability differ?
Porosity is the measurement of air pores in soil (rock space) permeability is the ability a soil or surface has to allow water to infiltrate.
Define porosity.
Porosity is the measurement of air pores in soil (rock space). the volume of open spaces in a material (in this case rock or soil)
Define Aquifer:
Porous, permeable rock or sediment through which groundwater flows (and can be extracted)
What is the Cody escarpment?
Prehistoric shoreline, Floridan aquifer is confined to its east and unconfined to its south and west
Darcy's Law
Q=kiA
Define Darcy's law including all of its terms.
Q=kiA Q=flux of groundwater (discharge) k=hydraulic conductivity (permeability specific to water) i= hydraulic gradient (the gradient of the potentiometric surface) A= cross-sectional area of aquifer
What areas receive the most precipitation? The least?
Rainfall averages 54 inches/year in FL, highest in Panhandle and SE coast (~60"/yr), lowest in central peninsula (~48"/yr)
Define Zone of aeration (also known as the vadose zone):
Region of subsurface where pore spaces are not completely filled with water (generally above zone of saturation)
How will rising sea level affect the US barrier island system?
Rising sea levels eventually overtake and drown barrier islands
Where is most of the phosphate mining done?
SW Central Florida
Where is the driest area in Florid in terms of the amount of precipitation relative to evaporation?
SW Florida (which receives only 0-3"/yr rainfall in excess of evaporation)
Discuss the role of Pleistocene sea level changes on the coastline of Florida.
Sea level drops due to glaciers forming at poles
How did sea level at the last glacial maximum (~18ka) compare to that of today?
Sea level was low as Earth's water was frozen in polar ice and continental glaciers
Generally speaking, how does the typical residence time for water in Florida Seepage (closed basin) lakes compare to drainage lakes that are more common in other areas? Why might this be some concern for Florida Lakes?
Seepage lakes are concerning due to their high residence time. This allows pollutants longer time to infiltrate the water table.
What general lake forming processes are the most common mechanism for lake formation in FL?
Sinkholes?
Where is peat found in Florida?
South Florida - Pleistocene, occurs in 7 geologic environments (e.g., river valley, lakes, swamps, coastal marsh)
What FL areas tend to have low occurrence of sinkholes and why?
South and Northeast FL
What is the significance of the "hydrologic divide" that occurs in the central part of the Florida peninsula?
South of the hydrologic divide Florida receives only rainfall input. Only 44% of precipitation falls south of the divide, but 78% of the population lives there.
In which water management districts(s) does Alachua Co. fall?
St Johns and Suwanee
How does a karstified terrain change in its appearance from the early stages of karstification to the most advance, mature karstified terrains?
Start with landscape dotted with sinkholes --> collapse of surface --> continued subsurface dissolution causes sinkholes coalesce and caverns to cause surface subsidence to form solution valleys--> continued erosion of limestone leaves tower (erosional remnants of limestone as in SE Asia)
What are some expected impacts/negative consequences of sea level rise in Florida?
State drowns. ☹ Economy retracts. Living areas retreat upland. Saltwater intrusion into the drinking water supply. New Yorkers find some other place to wait to die.
Where is the Apalachicola River's mouth?
Sumatra, center Panhandle
What are the main processes by which water moves through the water cycle?
Surface and groundwater inflow, evapotranspiration, rainfall, surface and groundwater outflow to the ocean, consumption
What was the basis by which the district boundaries were established?
Surface flow of water
About how much of Florida's water input comes from surface water inflow?
Surface=26 billion gallons/day
Where in Florida has the highest concentration (and number) of springs?
Suwannee River Water Management District
Identify one Florida geographic/geologic feature associated with the interglacial high stand (~150ka) and shoreline?
Terraces as old shorelines, old deltaic features indicating old shorelines, coral reefs higher than today (e.g., outcrop in Key West)
Discuss the overall role of the Cody escarpment in affecting the hydrology of N central Florida making specific note of differences in surface drainage and springs in the different terrains that it helps to define.
The Cody escarpment separates the northern highlands and the southern lowlands. It also approximates the transition area between the confined and undefined Floridan aquifer system. The northern highlands are a system overlain by a thick layer of clay, the south and west regions is unconfined, and the clay units are absent. Also, many of the rivers that cross the Cody Scarp goes underground and reemerges downstream as a spring (except for the Suwannee).
What is wave refraction and what causes it?
The bending of a wave as it propagates over different depths
Compare the karst of Florida to the Karst of Cuba?
The difference is age and uplift. Cuban karst is older (150 Ma) than Florida's (25-60 Ma) and has undergone uplift making it subaerially exposed. • Cuba=150 ma (Late Jurassic) Allochthonous carbonate sequence. The Miocene karst systems range from low elevation platform flow systems similar to Florida • Florida=25-60 Ma similar to that of Cuba.
What are some of the consequences of wave refraction?
The effects of wave refraction is that the waves strike the shoreline at a lesser angle than the angle of approach; in other words, the waves strike more nearly parallel to shore, not completely parallel, but more nearly parallel. The effects of wave refraction also tend to concentrate wave energy on headlands or protrusions that stick out of the coastline and tend to defocus or diverge the energy in embayments.
What is the current approximate rate of Global Sea level rise?
The global sea level rise rate in 2016 is estimated at 3.4 millimeters per year
What is the difference between the zone of saturation and the zone of aeration?
The zone of saturation (max water capacity) lies beneath the water table, while the zone of aeration lies above the zone of saturation and below the surface. It is known as the unsaturated zone (there is dry porosity)
How does the thickness of the Floridan Aquifer generally vary along the FL Peninsula?
Thicker and more deeply buried in south
What is the mixing zone and why is it an area of extensive carbonate dissolution?
This is a portion of the aquifer, where the initial dilution of discharge takes place. This is because reverse reactions such as mineral dissolution and dedolomitization occur in carbonate aquifer systems. The geochemical reactivity of the fresh-water/salt-water mixing zone results from the nonlinearity of geochemical parameters as a function of ionic strength and causes extensive dissolution in coastal carbonate rocks.
Define Water table:
Uppermost surface of the zone of saturation (separates the zone of saturation from the zone of aeration).
For lakes that do stratify which months to they tend to stratify and during which months are they well mixed?
Warm monomictic lakes tend to mix in the winter and stratify in the summer.
Define Groundwater:
Water found in the pores of soil and sediment, plus narrow fractures in bedrock
How has water use/demand in Florida changed in recent decades? What has been the primary factor driving that change?
Water usage in Florida has increased overall water usage by 21% mostly because of public supply. Although agriculture has increased by 34% public supply has increased by 17%, Florida's population has increased by 8.5 million in the last 25 years.
Why is the Floridan Aquifer unconfined there?
Wave erosion during sea level lowstands
How does pumping water from a well affect the water table?
Withdrawing water from wells forms a cone of depression in the potentiometric surface (which in the case of an unconfined aquifer is the water table). The locally steepened hydraulic gradient allows one to pump water from the well faster than the water can come in from farther away to replace it. This can lead to groundwater depletion. (Cone of depression)
What are some landforms and geologic features associated with karstified terrains?
sinkholes, solution cavities (caves, caverns), speleothems (stalactites, stalagmites), poorly developed surface drainage systems/patterns, disappearing streams, solution valleys, tower karst (mature)
Identify relict coastal forms associated it former shorelines in peninsular Florida.
~60 m below current sea level, we see what appear to be old coastal shorelines, more specifically, old barrier islands
Discuss the specific geologic conditions in Florida that most favor formation of each type as discussed in the Tihansky paper?
· Solution/subsidence/dissolution sinkholes - most intensive where the water first contacts the rock surface; where flow is focused in preexisting openings in the rock, such as along joints, fractures, and bedding planes, and in the zone of water-table fluctuation where ground water is in contact with the atmosphere. · Cover-subsidence sinkholes - the covering sediments are permeable and contain sand. · Cover collapse sinkholes - the covering sediments contain a significant amount of clay.
Which regions are not dominated by barrier islands?
• Big Bend Marsh Coast (the armpit of FL) • Ten Thousand Mangrove Coast (SW FL west of Everglades)
What are some issues of concern related to groundwater resources in southeast Florida?
• Biscayne Aquifer's limitations • Saltwater intrusion WHAT ELSE?!?!
What are the two main lake classifications based on drainage characteristics:
• Drainage Lake - contains surface outflow (shorter residence times, level reflects outflow elevation) • Seepage Lake - no surface outflow (longer residence times, level reflects water table)
What are the main aquifers that are used in Florida to provide municipal water supplies? List each of the main aquifers, and describe them in terms of their lithology and degree of confinement. In each case identify the region of Florida that uses that aquifer for their supply.
• Floridan Aquifer - • Intermediate Aquifer - • Surficial Aquifer - • Biscayne Aquifer -
What is the chemical reaction that leads to karstification?
• H2O(l) + CO2(aq) <-> H2CO3(aq) (known as carbonic acid) • H2CO3(aq) + CaCO3(s) <-> Ca2+(aq) + 2HCO3-(aq) [2HCO3-(aq) <-> H2O + CO2]
What is the difference between a monomictic lake and a polymictic lake?
• Monomictic lake - seasonal mixing and stratification • Polymictic lake - wind mixed, therefore mixes multiple times per year • Warm monomictic lake - mixing occurs in the winter and stratifies in the summer
Define the 6 main coastal regions in Florida as discussed by Dr. Jaeger. Identify each on a diagram or map of Florida?
• Northwest Barrier Chain (NW panhandle) • Big Bend Marsh Coast (the armpit of FL) • West-Central Barrier Chain (west of Tampa) • Ten Thousand Mangrove Coast (SW FL west of Everglades) • Florida Keys • FL East Coast Barrier Chain
Which regions are dominated by barrier islands?
• Northwest Barrier Chain (NW panhandle) • West-Central Barrier Chain (west of Tampa) • FL East Coast Barrier Chain
Identify the dominating influence (tide/wave) on the 6 main coastal regions in Florida as discussed by Dr. Jaeger.
• Northwest Barrier Chain (NW panhandle) - Small waves & very small tides • Big Bend Marsh Coast (the armpit of FL) - Small waves & very small tides • West-Central Barrier Chain (west of Tampa) - ??? • Ten Thousand Mangrove Coast (SW FL west of Everglades) - Small tides>no waves • Florida Keys - Small tides>no waves • FL East Coast Barrier Chain - Medium tides>medium small waves
From what kinds of deposits are heavy minerals mined (an example would be the Trail Ridge deposit)?
• Occur in counties of NE Florida •Plio-Pleistocene beach ridges (e.g. Trail Ridge) •Major product is titanium ores •Secondary products are • Zircon •Monazite •Staurolite (only current US producer as of 2013) • Major product is titanium ores (Ilmenite, Rutile, Leucoxene) • Use in paint, paper, foods, and abrasives.
What are the strata associated with petroleum exploration? When did they form?
• Original discovery in SW Florida in 1940s: Cretaceous Sunniland Limestone • Major discovery in the 1960s in the Panhandle-Jurassic Smackover Ls and Norphlet Sandstone (Jay Field) • 6,000 barrels/day (U.S.>9,000,000 barrels/day)
For which commodity(ies) is Florida the #1 US producer? Which other ones do we have a significant impact (top 5).
• Rank 1st in phosphate production (65% of US production of fertilizers) • Rank of 6th among 50 states in non-fuel minerals • Only current US producer of Staurolite as of 2013. • Heavy minerals • Fuller's Earth • Produce & sugar cane.
What are the three major types of sinkholes? Define/discuss each including overall morphology and the manner in which each form.
• Solution or subsidence sinkholes • Cover-subsidence sinkholes • Cover collapse sinkholes
What part(s) of Darcy's Law defines flow velocity?
• The movement (direction and rate) of groundwater flow is governed by a scientific law called Darcy's Law. • Groundwater flows from regions of high pressure (places where the potentiometric surface is high) to regions of low pressure. Flow direction is directly down gradient. Flow velocity is a function of the steepness of the pressure gradient and the permeability of the rocks or sediments.
What is the economic impact of Florida's mining industry to the state?
•Contribute 5.47 billion to GDP •2011 Non-fuel production valued at 3.43 billion •193 mining operations in the state
From what age strata are these materials being extracted? What conditions allowed these phosphate deposits to form?
•Deposited in Miocene (upwelling) •Reworked/concentrated in Pliocene •Richest Phosphate (phosphorite) deposits in Bone Valley Member of Peace River Fm which is part of the Hawthorn group
Florida Aquifers characterization
•Provides 60%+ of domestic supply •Mostly Eocene limestone with a Miocene clay confining unit except in the Gulf coastal lowlands (west of Cody Escarpment where the Miocene clays are not present.)
