Deleted
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Post by Deleted on Oct 21, 2013 14:11:06 GMT -5
I know the acid water in the river ate away a gorge or river channel thru the limestone. The steep walls of limestone are staring at you as you float on the river when it is low. On top of those walls is the coral. But the coral that was sitting over the river on the limestone is all sitting in the bottom of the river since the limestone was dissolved out from under it. Also sitting on the top of the limestone walls is dense clays that the coral is imbedded in. If the limestone /cherty coating on the coral i sent you Scott was sitting in the acid water for a long period of time is it possible that it is neutral in ph ? Or even acidic... Petrified wood and coral replacements puzzle me too. I see so many partial silicifications of the coral. And hollow botyroidal/drusy cavities is another story. But the other partial silicifications are in many strange forms in the coral. Typically breaking into tubes with hex cross sections. You called them spaghetti Scott. I never see healed silicifications in the coral-never. Like shrinkwood and breccias. And many of the silicifications are glass like. And the glassier they are the less anatomy preserved... The more incomplete the silicification the more anatomy that was preserved, to a point. I started a new thread so as to not take Tela's thread too far afield. BUT I would like to explore this topic further. We have too many smart people here to not follow this path intelligently. #1) none of the coral you have sent me has any limestone. None of it reacts to hydrochloric acid. It is all silica stuff. #2) based on your observations; it seems to me that there is a "continuum" from what you describe as "glassy" with no internal coral anatomy (casts) to fully anatomy-ed coral fossil specimens. Some of the coral is completely dissolved away by acidic streams, others less so and some (perhaps rarely) are left untouched by acid. Then the silica-event happens and silica-fies the specimen in question. #3) coprolites smell like poop when cut with water. Been there smelled that! This seems to indicate the poop is indeed petrified leaving the original meadow muffin intact. *** #4) it is pretty clear petrified wood follows the same path as I describe for the coral above. A continuum from fully petrified wood to fully "casted" wood shapes and every single step in between. Therein lies my dilemma. To silicify anything we need a source of silica. Pet wood, palm, coprolites... = volcanic action. In your region I can visualize diatoms being this silica source. As you know I am studying the synthesis of lapidary grade agates. I am close and feel I understand the basic chemistry pretty well. To transport silica from the source (lava/diatom beds) we need a HIGH pH. That is a pH well over 9. We can get a high pH from the carbonates in solution, but calcium carbonate buffers a solution to a pH of 8.0 not high enough to transport silica. In the volcanic method we can get high pH solutions from volcanic ash dissolved in rainwater. The following questions are posed to all whom may wish to share knowledge. Where is the source of alkali in the fossil coral formation scheme? Is there another chemistry that allows for silica transport than the one I explain? Do you know how old your fossil coral is? Is there some volcanic action I am unaware of (easily the case) that coincides in era with the fossil coral formation? *** (actually despite the bad odor, this is really kinda cool to consider. Think about it for a moment, you can actually smell the stench of living dinosaurs, millions of years later!)
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grayfingers
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Post by grayfingers on Oct 21, 2013 15:03:35 GMT -5
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Post by Deleted on Oct 21, 2013 16:30:04 GMT -5
Sure, of course. The source of silica is there. Diatoms, sponges and perhaps others. The missing piece to that part of the puzzle is the source of the alkali to make the silica solution and re-deposit into the corals happen. Or did you mean to say the alkali could come from the sponges? That website is nice. They have figure 2-3 reversed, but otherwise quite nice. He mentions sponges as No doubt. Silica by itself is not mobile. We need some alkali to dissolve it into a mobile solution form. In the case of Indo fossil corals, they have no shortage of volcanic activity to provide the alkali (and silica for that matter). Utah and other western fossil corals, same story.
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Post by Deleted on Oct 21, 2013 16:38:07 GMT -5
This websiteputs volcanic activity in the Georgia/Florida region This seems too old. Same webpage Still seeking alkali for the Florida coral fossils! lol
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Post by Deleted on Oct 21, 2013 17:27:15 GMT -5
Too much brain power needed. I'm not worthy. Jim
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Sabre52
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Post by Sabre52 on Oct 21, 2013 17:49:42 GMT -5
*LOL* I had initially intended to become a large animal vet but chemistry killed me in college. So chemical explanations are beyond me. I do know Florida/ Georgia coral is relative young, maybe 10 million years as is Texas pet wood. AZ pet wood is like 65 million years old I think. I thought all pet wood and coral was a simple cellular replacement and limestone itself and coral being calcium carbonate are themselves alkali not acidic. At least we are all limestone soil here and its highly basic.
That being said, all coral and pet wood, being organic in origin, are pretty permeable and porous. I figured the silica gel simply penetrated the fossils and replaced them to some degree. Same as with sagenite or other pseudomorphs that are replacements of calcium structures by silica. That makes me think the silica gel must be in a slightly acidic solution too. As some have said, only the specimens where complete silica replacement has occurred are agate hard all over. Many pet wood specimens still have wood fibers inside and many corals still have soft calcium spots. Coprolites also often have organics still in suspension in the agate. Casts of course are simply voids left by total decomposition of the organic specimen that have been filled in with silica to create opal or chalcedony.....Mel
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Post by Deleted on Oct 21, 2013 19:17:34 GMT -5
Silica gel in a solution less than about pH 10 solidifies into solid form. This is verifiable, even on this website. In the tutorial for using water glass to stabilize stones it mentions using vitamin C to harden the gel.
Where I am going with this is a possibility for an alternate chemistry. One that makes Jim's coral harder/tougher than normal agatized stuff. I'd like to sort out that chemistry for my experiments.
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jamesp
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Post by jamesp on Oct 21, 2013 20:02:09 GMT -5
I have listened to a geologist or two from Florida talk about the coral. They said that something about the process was very unique and specific to the Florida coral formation.
Scott, i would say that the calcium is long gone. The coral is in the river bottom because acid water flowed over it. How long? Long enough to eat away the limestone bedrock it was sitting on. Like 10-50 feet of it. It kept dissolving away and the coral sat on top of it the whole time it dissolved away, getting lower and lower. The coral does not exist in the limestone bedrock. It is sitting on top of it(from another age i think). So it has been in a heck of an acid bath.
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jamesp
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Post by jamesp on Oct 21, 2013 20:09:34 GMT -5
Could it be radiation that silicified it?(being a smart ass here) Look at the color. From a desk lamp.... Very well silicified coral slab 1.25 inches thick Plain natural light 5000K halide lamp from Home depot shining into thick slab. Same light used in above photo.
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Post by rockpickerforever on Oct 21, 2013 20:18:44 GMT -5
Would the silica have to come from volanic activity? Why not fallout from the Chicxulub meteor that crashed into the Yucatán Peninsula? That ash would also be silica, right? So that would have been, oh, 66 million years ago, the end of the Cretaceous.
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jamesp
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Post by jamesp on Oct 21, 2013 20:21:40 GMT -5
I magnified a partial silicification so the tube can be seen in a close up. Not a solution to the silica dilemma but interesting. This hollow arrangement keeps me challenged in finding solid silicifications. So many are like this and you never know till you perform hammer surgery.
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jamesp
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Post by jamesp on Oct 21, 2013 20:25:05 GMT -5
I have heard ash theory from the meteor that hit the Yucatan. That is one thing i have heard. Jean, you jogged my memory on that one. Some think Florida is part of a rim from a meteor impact.
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jamesp
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Post by jamesp on Oct 21, 2013 20:36:50 GMT -5
I have never found a cast of coral. i will tell you why. Every one that is sawn or tumbled has pores in every cubic centimeter. Not easy to see but visible in glare. Like the white coral above that glows weird when back lit has thousands of tiny capillaries in it. You would guess cast but they are never casts. They all have that fingerprint. Artifacts have the same fingerprint giving away their makeup. They always know if the artifact is coral. On any conoidal chip the capillaries are visible.
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Post by rockpickerforever on Oct 21, 2013 20:56:45 GMT -5
Silica replacements, not casts for sure. Replacements would happen cell by cell, replacing the original structures - silica for calcium, or limestone or whatever. Casts would be some object being encased in sediment, then dissolving or rotting away, leaving a void - consider it a mold. Then this fills in with another substance. Just the outer shape is the same, no structure whatsoever.
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Post by Deleted on Oct 22, 2013 12:04:18 GMT -5
jamesp - it's here. lol I thought you had said that you had casts because some were glassy with no coral anatomy. My bad. I'd love to hear from the Florida educator about them.
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jamesp
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Post by jamesp on Oct 22, 2013 12:32:46 GMT -5
I remember thinking i had casts but with those capillaries in every piece it spells replacement.
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jamesp
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Post by jamesp on Oct 22, 2013 12:34:55 GMT -5
Coral collection is so attacked by Florida info has been swept under carpet. I will start hunting.
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jamesp
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Post by jamesp on Oct 22, 2013 13:06:35 GMT -5
We already know this
They are found in ancient ocean beds, where silica rich groundwater has percolated through them and over time has replaced it's calcium carbonate skeleton with a hard variety of Chalcedony. This leaves the ornamental fossil with a sometimes banded stone look.
It is about 38-25 million years old and from the Oligocene-Miocene period. These fossils are found in a variety of colors- white, gray, brown, black, yellow and red. Different trace minerals in the agate create these colors.
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jamesp
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Post by jamesp on Oct 22, 2013 13:13:32 GMT -5
And about the same as above
Identification: Agate, or chalcedony, is a variety of cryptocrystalline quartz (SiO2). It is found in a variety of colors, typically gray, brown, black, white, and sometimes red. Fossil corals and mollusks may be replaced with agate deposited by silica-rich ground water percolating through limestone. In 1979 the Florida Legislature designated agatized coral as the Florida State Stone. It is described in the statute as “a chalcedony pseudomorph after coral, appearing as limestone geodes lined with botryoidal agate or quartz crystals and drusy quartz fingers, indigenous to Florida.” Occurrence: Much of Florida’s agate, including the Tampa Bay agatized coral, formed in the Oligocene-Miocene Hawthorn Group sediments (see time scale). Once abundant at Ballast Point in Tampa, it is occasionally dredged up in the Tampa and Clearwater areas. It also occurs in limestones along the Econfina, Withlachoochee and Suwannee Rivers. An Oligocene variety is sometimes found in Suwannee Limestone quarries north of Tampa. Use: Agatized coral, particularly in the form of large geodes, is prized by gem and mineral collectors.
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jamesp
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Post by jamesp on Oct 22, 2013 13:36:28 GMT -5
This info is created by the St. John's River Water Management 'agency' and is descriptive of typical Ocala Aquifer ground water for S. Georgia and N. Florida. I know that Salt Springs has a long list of constituents that have unique effects like eroding a trough through the ceramic coating on a bathroom sink at a leak running across it, growing plants as if fertilizer and micronutrients have been added to the water, preventing you from washing soap off your body, noted for supplying a high PH to the acidic environment, creating prostrate problems that drink sweet tea made out of it, removing protective coating from bait minnows, and keeping me and early Spanish explorers youthful-a la the fountain of youth.
Note what it says about silica under sodium.
Definitions of water quality variables
Alkalinity Alkalinity is an indicator of the capacity of solutes in water to react with and neutralize acid. Alkalinity is produced by the reaction of carbon dioxide and water in the atmosphere or the soil zone, the dissolution of calcite and dolomite, and the oxidation of organic materials by microorganisms. Bicarbonate is the dominant anion in natural waters and is the dominant constituent of alkalinity. As reported for the spring data, alkalinity (as CaCO3) includes bicarbonate (HCO3–), carbonate (CO32–), and other anions that can be neutralized by a strong acid.
Calcium The calcium ion (Ca2+) is dissolved from most soils and rocks, and especially from limestone, dolomite, and gypsum. Calcium is a dominant cation resulting from the chemical weathering of the mineral calcite (CaCO3) in limestone and the mineral dolomite (CaMg(CO3)) in dolostone. Calcium is also present in large concentrations in some brines, seawater, and connate water. The concentration of dissolved calcium is a result of the water’s contact with aquifer materials, residence time, and flow path, with highest concentration in alkaline waters that are in equilibrium with aquifer materials. Calcium causes water to be hard and contributes to the scale-forming properties of water.
Chloride The sources of chloride (Cl–) in Florida’s aquifer systems are the lateral intrusion of recent seawater, residual seawater in an aquifer, and marine aerosols. Chloride is a relatively inert element that does not readily enter into mineral reactions, so the occurrence of chloride is useful for identifying laterally intruded seawater and mixing of fresh groundwater with residual seawater. Concentrations above 300 mg/L in combination with sodium give a salty taste to water. The drinking water standard for chloride is 250 mg/L.
Fluoride Fluoride (F–) in Florida’s aquifer systems is derived mostly from the weathering of carbonate-fluorapatite in the Hawthorn Group, indicating that the water has come into contact with the Hawthorn Group at some time in the past, or from the mixing of seawater with groundwater. The drinking water standard for fluoride, which addresses toxicity, is 2.0 mg/L. In small amounts of less than 1.0 mg/L, fluoride is considered beneficial for preventing cavities.
Magnesium Magnesium (Mg2+) is dissolved from practically all soils and rocks, especially magnesium-rich clays in the Hawthorn Group and dolomite in the Floridan aquifer. Magnesium is present in large concentrations in some brines, seawater, and connate water. It causes water to be hard and contributes to the scale-forming properties of water.
Nitrate + Nitrite Nitrogen compounds occur in groundwater as a result of specific land uses, the leaching of organic soils, and from precipitation. Sources of nitrogen from man’s activities include agricultural fertilizers, animal wastes, and human wastes. Nitrogen is transformed between organic nitrogen (TKN), ammonium (NH4+), nitrite (NO2–), nitrate (NO3–) and other nitrogen compounds depending on oxidation/reduction conditions, microbial activity, and plant utilization. Nitrate is the stable form of nitrogen in oxidizing environments. Nitrite is unstable in the presence of oxygen and is present in small concentrations in most waters. Once nitrate enters the aquifer and is isolated from environments where denitrification and plant fixation occur, nitrate behaves more-or-less conservatively and can move long distances in aquifers. The drinking water standard for nitrate is 10 mg/L as nitrogen, which is intended to protect human health and is not based on the protection of ecological systems. Elevated nutrient concentrations may lead to increases in algae growth, which decreases water clarity and changes the aesthetic qualities and ecology of springs.
Phosphorus / Orthophosphate Sources of phosphate (orthophosphate, PO43–) in groundwater include the dissolution of phosphate-rich sediments, leaching from organic sediments and plant materials, agricultural fertilizers, human waste effluent (such as from septic tank systems), industrial effluent, and other waste disposal practices. The orthophosphate ion is soluble in acidic waters, such as occur in siliciclastic horizons of the surficial aquifer system, but insoluble in alkaline aquifers, such as occur in the Floridan aquifer. In carbonate-rich aquifers, orthophosphate is removed by precipitation of carbonate-hydroxylapatite and alkaline waters seldom have detectable phosphate as a result.
pH The variable pH reflects the potential for acid-base reactions in water. The pH of aquifer water is a result of past chemical reactions, and it is also a measure of the potential for reactions, if chemical equilibrium between the water and surrounding rock has not been established. The pH of a water sample is a measure of the activity of hydrogen ions and is expressed in logarithmic units, with pH representing the negative base-10 log of the hydrogen ion activity in moles per liter. The pH of pure water at 25°C is 7.00, or neutral. Values less than 7.00 are acidic and values greater than 7.00 are basic, or alkaline. Dissolved gases such as CO2, SO2, and NO2 increase the number of hydrogen ions and cause waters to be acid. Carbonates, bicarbonates, hydroxides, phosphates, silicates, and borates decrease the number of hydrogen ions and cause waters to be basic. The hydrogen ion (H+) is generally the cause of acidity, and bicarbonate (HCO3–) is generally the source of alkalinity. Water with pH less than 6.5 is likely to be corrosive and have high iron and phosphate levels. Water with pH greater than 8.5 may result in turbidity from the precipitation of carbonate minerals, or high pH values may be the result of well drilling fluids remaining in the well after construction. Rainwater has a pH of about 5.5. As rainfall infiltrates into the ground, it reacts with carbon dioxide in the soil, resulting in low pH values typically measured in surficial aquifer wells. As water moves downward and interacts with aquifer minerals, acidity is consumed and alkalinity is produced, resulting in higher pH levels. For example, carbonate minerals such as calcite in the Floridan aquifer are highly reactive, raising pH levels.
Potassium The principal sources of the potassium ion (K+) are the mixing of fresh groundwater with seawater in coastal transition zones and with connate water, and from the weathering of clays and feldspars. Weathering of potassium feldspars and clays is not considered a dominant process in Florida due to the scarcity of these minerals in aquifer sediments and slow weathering reaction rates. Potassium is rarely present in concentrations over a few milligrams per liter because potassium-rich sediments are scarce in the aquifer system and because potassium is immobilized as a nutrient by plants and sorbed onto clays.
Specific conductance Specific conductance is a measure of the ability of water to conduct electric currents and is dependent on the concentrations and types of ions in the water and on temperature. Specific conductance has a strong positive correlation with TDS and with chloride concentrations. It is expressed in micromhos per centimeter at 25°C. There is a good statistical correlation between specific conductance and the total dissolved solids concentration and it can be used to approximate the dissolved-solids concentration of water.
Sodium The primary sources of sodium (Na+) in Florida’s aquifer systems are the mixing of fresh groundwater with seawater along the coast and in coastal transition zones, upconing of seawater from deeper zones, the weathering of sodium-rich minerals such as clays or feldspars, and marine aerosols. Sodium-rich minerals are found in siliciclastic horizons of the surficial and intermediate aquifer system and minor amounts occur in the Floridan aquifer. The drinking water standard for sodium is 160 mg/L.
Sulfate Sources of sulfate (SO42–) in groundwater include the dissolution of gypsum and anhydrite, the weathering of pyrite and iron sulfides, residual formation water, the lateral intrusion of seawater, precipitation that contains sulfur oxides, and marine aerosols. Sulfate is usually present in mine waters and some industrial waters. Sulfate in water containing calcium forms a hard scale in steam boilers; in large concentrations, sulfate in combination with other ions gives a bitter taste to water. The occurrence of sulfate depends upon the reduction/oxidation potential of the water. In reducing conditions, sulfate reduction produces hydrogen sulfide, which is the cause of the rotten egg odor in some wells. In oxidizing conditions, sulfides may be oxidized to sulfates. The drinking water standard for sulfate is 250 mg/L.
Temperature The temperature of groundwater is controlled by climatic conditions, cultural activities, heat flow from the earth’s interior, and chemical reactions in the aquifer system. In shallow aquifers, water temperature is usually controlled by climatic conditions, as opposed to other possible causes. Water that has recently entered the aquifer system normally reflects atmospheric temperature at the time of recharge. In deeper aquifer systems, temperature can be affected by recharge from shallow environments, earth heat flow, and chemical reactions. Temperature measurements are recorded in the field.
Total dissolved solids Dissolved solids in groundwater are the result of mineral dissolution reactions. Total dissolved solids (TDS) is a general measure of the total mass of ions dissolved in water and is usually determined from the weight of the dry residue remaining after evaporation of the volatile portion of an aliquot of the sample. Total dissolved solids values are widely used in evaluating and comparing water quality. Water that has recently entered an aquifer in recharge areas has had less time to dissolve minerals than has water that has traveled for some greater distance through the aquifer. TDS concentrations are higher for water from an aquifer comprised of reactive materials, such as limestone, than for an aquifer composed of quartz sand materials, which are relatively inert. TDS has a guidance criteria in groundwater of 500 mg/L. Water with a high TDS concentration may have an unpleasant taste, may contribute to the development of kidney stones, and may result in scale or precipitates in hot water heaters.
Total organic carbon All natural waters contain organic material. The amounts present are small compared to the inorganic concentrations, but even small amounts can have significant effects on chemical properties. Organic carbon concentrations in groundwater are normally smaller than in surface waters.
Isotopes
An analysis of stable and radioactive isotopes is also provided for selected springs. Stable isotopes are used to identify sources of water and to learn more about hydrologic processes such as recharge, evaporation, mixing, and water-rock interactions. Radioactive isotopes are generally used for age-dating water because these isotopes decay over a period of time at a known rate.
Isotopes are atoms of the same chemical element that differ in mass because of a difference in the number of neutrons in the nucleus. There are two types of isotopes: stable and radioactive. Stable isotopes are used in hydrologic studies to identify sources of water and to learn more about hydrologic processes such as recharge, evaporation, mixing, and water-rock interactions. They are also useful in age-dating. Stable isotopes monitored for age-dating are helium-3, helium-4, and neon. Radioactive isotopes are generally used for age-dating water because these isotopes decay over a period of timeat a known rate. The radioactive isotopes monitored in age-dating are tritium and carbon-14.
Helium-3, Helium-4 and Neon Concentrations of helium-3 and helium-4 can be used to determine an age for a water sample. Helium-3 is a radiogenic isotope of helium. It is produced by the radioactive decay of tritium. Both helium-3 and helium-4 are stable isotopes of helium. Helium-3 was measured to calculate the tritium/helium-3 age of the sample. Helium-4 was measured to correct the helium-3 concentration for contamination of helium-3 due to atmospheric sources — that is, helium-3 concentrations arising from equilibration with air during recharge and entrainment of air bubbles. Neon is a noble gas. Neon was measured to correct helium-4 for helium produced through the uranium and thorium decay series. The helium-3 in the water is assumed to be of atmospheric and tritogenic origin. This condition usually prevails in shallow aquifers containing predominantly young waters occurring in sediments and rocks of relatively low uranium and thorium content. Additional helium sources may be present in aquifers where the rocks are enriched in uranium or thorium, or in groundwater samples in which young water has mixed with relatively old water containing radiogenic helium. In these cases, the measured neon content can be used to calculate the additional helium.
Tritium Tritium is a radioactive isotope of hydrogen that is produced naturally in small amounts by the interaction of cosmic rays with the earth's atmosphere. Cosmogenic tritium enters groundwater by way of rainfall at a concentration of approximately 3 to 5 tritium units (TU; a tritium unit equals 3.2 picocuries/liter) (Kaufman and Libby 1954; Robertson and Cherry 1989). With the onset of atmospheric nuclear testing in 1953, the tritium concentration in rainfall began to increase. At Ocala, Florida, the tritium concentration in rainfall increased to as high as 700 TU in 1963. In 1988, the tritium concentration in rain at Ocala was not measurably different from the estimated pre-1953 concentration. Because of the difference in tritium concentration in rainwater before and after 1953, tritium has been used as a hydrologic tracer to date recent groundwater. The half-life of tritium is 12.43 years, which means that the tritium concentration decreases by one-half every 12.43 years. Tritium decays to Helium-3.
Tritium/Helium-3 The age determined by measuring the tritium and helium-3 concentrations in the sample is referred to as the piston flow age. It would be the age the water sample would have if the water traveled as a slug or “piston” through the aquifer.
Carbon-14 Carbon-14 is a radioactive isotope of carbon formed by the reaction between cosmic rays and nitrogen in the atmosphere. Carbon-14 combines with oxygen to form carbon dioxide, which is taken up by plants or adsorbed by rain and is found in surface water bodies. When plants, animals, and groundwater are no longer exposed to atmospheric carbon dioxide, the carbon-14 content begins to decline through radioactive decay. The radiocarbon content of groundwater decreases at a rate equal to the half-life of carbon-14, which is 5,730 years. Therefore, water that has been underground for an extended period of time will have a lower concentration of carbon-14 than water that has only recently entered the ground. The measured carbon-14 content of groundwater is expressed as a percentage of the modern carbon-14 content of groundwater, or percent modern carbon (pmc). Because the content of carbon-14 in the atmosphere increased after 1953, the base year for modern carbon-14 is 1950. The carbon-14 age is based on the Fontes and Garnier (1979) model for a system open to carbon dioxide. It represents the age for a leaky aquifer or an aquifer near a recharge area.
Carbon-13 Carbon-13 is a stable isotope of carbon. It normally is expressed with a delta notation which means it is measured with respect to a standard. The standard for carbon-13 is the PeeDee belemnite (PDB) or Vienna PDB carbonate standard. Carbon-13 is generally used to correct the measured concentration of carbon-14 for reactions along the flow path. Dissolution of limestone dilutes the concentration of carbon-14 in the system. Delta carbon-13 is used to correct for this dilution. Delta carbon-13 is generally near -12 in recharge areas and increases (becomes more positive) in discharge areas.
Laboratory water quality variables and field measurements
Variable EPA Storet Discharge, cfs 61 Alkalinity, total, mg/L as CaCO3 410 Calcium, dissolved, mg/L as Ca 915 Calcium, total, mg/L as Ca 916 Chloride, total, mg/L as Cl * 940 Fluoride, dissolved, mg/L as F 950 Fluoride, total, mg/L as F 951 Magnesium, dissolved, mg/L as Mg 925 Magnesium, total, mg/L as Mg 927 Nitrate + nitrite, total, mg/L as N * 630 Nitrate + nitrite, dissolved, mg/L as N 631 Orthophosphate, total, mg/L as P * 70507 pH, field 400 Phosphorus, total, mg/L as P 665 Potassium, dissolved, mg/L as K 935 Potassium, total, mg/L as K 937 Sodium, dissolved, mg/L as Na 930 Sodium, total, mg/L as Na 929 Specific conductance, field, µmhos/cm at 25 °C 94 Specific conductance, lab, µmhos/cm at 25 °C 95 Sulfate, total, mg/L as SO4 * 945 Total dissolved solids, mg/L * 70300 Total organic carbon, mg/L as C 680 Water temperature, °C 10 Units: µmhos/cm = micromhos per centimeter mg/L = milligrams per liter cfs = cubic feet per second * Data for these variables are graphed and analyzed for trends if spring sampled at least 8 times
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