The Hidden Mission Forum accepts donations via paypal. Support your favorite forum!
0 Members and 2 Guests are viewing this topic.
GeoreactorFrom Wikipedia, the free encyclopediaYou have new messages (diff).Jump to: navigation, searchThe georeactor is a proposal by Dr. J. Marvin Herndon that a nuclear fission reactor may exist and operate at the Earth's core and serves as the energy source for the geomagnetic field. Dr. Herndon had earlier proposed the existence of fission reactors at the centers of large gaseous planets such as Jupiter.Contents [hide]1 Natural Nuclear Reactors 2 Planetary Fission Reactors 3 The Georeactor 4 Stellar Fission Reactors 5 Criticism 6 Planetary Fusion Reactions 7 The Georeactor in Popular Fiction 8 Sources 9 See also 10 External links Natural Nuclear ReactorsSince the 1970s, geochemistry has documented the origin and existence of naturally-occurring slow fission reactors in uranium-bearing geologic formations at Oklo in Gabon, Africa. The Oklo natural nuclear fission reactors operated over 2 billion years ago, when the natural occurrence of the uranium-235 isotope (required for the fission chain-reaction) was much higher.Planetary Fission ReactorsLarge, gaseous planets, such as Jupiter, radiate more energy into space than they receive from the Sun. (In the case of Jupiter, the radiated energy is almost twice the received energy.) The source of this energy is conventionally attributed to gravitational contraction, since gravity seems to be the only force sufficient to account for the quantity of energy released. In 1992, Dr. J. Marvin Herndon, an American nuclear geochemist, postulated that the excess energy could be explained by the existence of a central nuclear reactor. High-density fissile elements (i.e. uranium) would be concentrated at the core and the extreme pressure and temperature at the planet's core would initiate the reaction. Herndon tested this hypothesis using calculations similar to those used in nuclear-reactor design and found that planetary-core natural fission reactors were feasible.The GeoreactorDr. Herndon subsequently realized that the calculations also permitted the existence of a similar reactor at the Earth's core. Dr. Herndon's calculations depend on certain unconventional assumptions regarding the composition of the core, in particular the oxidation state of uranium and the likelihood of its precipitating to the center. He justifies these assumptions by comparison with the composition of enstatite chondrite meteorites, which do have the necessary highly reduced oxidation states.Dr. Herndon argues that the georeactor is the energy source for the Earth's magnetic field, and that variations in the strength and direction of the field can be explained by natural variations in the operation of the georeactor.Stellar Fission ReactorsAnother possible instance of central nuclear fission may occur in protostars. Ignition of fusion reactions in the cores of stars and protostars requires tremendous temperatures and pressures, which are difficult to attain. Dr. Herndon suggests that the fusion reactions may, in fact, be ignited by a central fission reactor in the same manner that a fusion bomb is triggered by a fission bomb.CriticismDr. Herndon's theory is not accepted by most geologists. However, Rob de Meijer and associates at the Nuclear Physics Institute in Groningen, the Netherlands, have proposed an experiment to measure the antineutrino flux from the Earth's core which they believe will validate Herndon's hypothesis. At present they are seeking funding for the project, which involves development of an underground laboratory in Curaçao.The following is taken from a San Francisco Chronicle article by Keay Davidson describing that test:One of Herndon's leading critics is planetary scientist David Stevenson of the California Institute of Technology. He says in an e-mail: "Herndon is a solid and knowledgeable person when it comes to (nuclear) reactors. But the amount of attention this (georeactor) idea has received is out of proportion with its plausibility. ... It's not complete nonsense, but it's highly unlikely. There are many instances in science where this happens. This one has merely received more attention than most. "The idea is based on two very dubious propositions: (a) That uranium (or any heavy element) would naturally go to the center of the Earth. This is almost certainly untrue. It is a misunderstanding of chemistry and statistical physics at a very fundamental level. (b) That there is something about Earth's heat flow or helium that is so wildly discordant with our usual ideas that it requires an outrageous hypothesis to explain it. This is incorrect." Planetary Fusion ReactionsIn seemingly unrelated work, Steven E. Jones of Brigham Young University has speculated on the existence of natural fusion reactions at planetary cores, continuing work initiated by Dr. Paul Palmer (also of BYU) in 1986. Their initial work was also focused on explaining the excess heat given off by Jupiter and then extended to include possible application to Earth. The term geo-fusion is used to describe their theory. Geo-fusion is a form of cold fusion (Althogh geo-fusion is not the type of room-temperature fusion described by Stanley Pons and Martin Fleischmann, Jones was working on muon-catalyzed fusion and was intending to publish his results simultaneously with Pons and Fleischmann, at the nearby University of Utah, when they "scooped" him with their public announcement). Jones hypothesizes that geo-fusion is driven by the high pressures present at planetary cores. Jones has suggested that measurements of the levels of tritium released by volcanic processes may provide a possible confirmation of the theory.The Georeactor in Popular FictionHerndon speculated as to the effects of a possible shutdown of the theoretical fission process in the Earth's core in, which was subsequently, without attribution, paralleled in the pulp science fiction book and film from 2003, The Core.Sources"Nuclear Fission Reactors as Energy Sources for the Giant Outer Planets", Naturwissenschaften 79:7-14, 1992 J.M. Herndon, "Feasibility of a Nuclear Fission Reactor at the Center of the Earth as the Energy Source for the Geomagnetic Field", Journal of Geomagnetism and Geoelectricity 45: 3423-437, 1993 Current Biography 64: 45-49, November, 2003 Discover Magazine, pp 37-42, August, 2002 "Nuclear Georeactor Origin of Oceanic Basalt 3he/4he, Evidence, and Implications", Proceedings of the National Academy of Science 100 pp. 3047-3050, 18 March 2003 Davidson, Keay (Nov. 29, 2004). "Scientific maverick's theory on Earth's core up for a test" San Francisco Chronicle Jones, S.E. and J. Ellsworth (2003) "Geo-fusion and Cold Nucleosynthesis" Tenth International Conference on Cold Fusion. Peat, David E. Cold Fusion: The Making of a Scientific Controversy. Chicago: Contemporary Books, Inc., 1989. ISBN 0809242435. See alsoStephen Baxter's Manifold: Origin Cold fusion External linksNuclear Planet.com Dr. J. Marvin Herndon's Website Retrieved from "http://en.wikipedia.org/wiki/Georeactor"Categories: Geology | Nuclear physics
113) Recent Papers of Steve Jones et al.Ludwik Kowalski (October 9, 2003)Department of Mathematical SciencesMontclair State University, Upper Montclair, NJ, 07043Many interesting papers were presented at the 10th international Conference on Cold Fusion (in Cambridge, August, 2003); some of them are already downloadable from the < http://www.LENR-CANR.ORG > web site. (click of ICCF10 PROCEEDINGS and scroll down to the list of papers). One of the most convincing evidence that the unexplained nuclear processes are real was presented by Jones et al. I am referring to his papers on the emission of neutrons and on the emission of charged particles. 1) The paper on neutrons reminded me of the old argument against cold fusion, absence of neutrons commensurable with the reported amount of excess heat. Suppose that excess heat, generated at the rate of 10 W, is due to well known thermonuclear fusion of deuterons. How many neutrons would be emitted in each second? To answer this question one must know that the amount of energy released from each thermal fusion event is about 3.5 MeV and that, on the average, one out of two events is associated with the release of a neutron. The other half are events associated with the release of protons. Converting 10W into 6.25*1013 MeV/s one finds 1.8*1013 fusion events per seconds and nearly 1013 neutrons per second. This result is by many orders of magnitude higher that what has been observed. The unavoidable conclusion, reached as early as 1989, was that thermonuclear fusion can not possibly by a dominant mechanism generating excess heat in cold fusion experiments. Nuclear reactions taking place in cold fusion remain unexplained (production of heat without emitting a lot of neutrons) but one thing is clear, they are very different from well known thermo-nuclear reactions. Who invented the terms "cold fusion" and “hot fusion?” These unfortunate terms suggest the idea that cold fusion reactions are the same as hot fusion reactions. As far as I know, nobody has ever made such claim, except journalists and some book writers. Did they deliberately create a “straw man” to justify criticism of cold fusion? It is easy to criticize people for claims they do not make. The real claim of scientists studying cold fusion is that some, previously unknown, nuclear processes occur at metals loaded with hydrogen isotopes.Therefore the issue of neutron commensurability, the central argument of those who criticize cold fusion, is totally irrelevant. Even a very small number of neutrons, emitted from metals loaded with hydrogen, is highly significant in the context of showing that something totally unexpected is taking place. That is why I was very impressed by the evidence, presented by Steve Jones et al., that neutrons have been detected. Their experiment was complicated by the fact that the emission rates are very small. The efficiency of detection of neutrons was maximized by using a setup of sixteen detectors in close proximity to metallic foils loaded with deuterium. The arrangement was able to detect approximately one out of ten neutrons, on the average. Additional complications resulted from presence of cosmic ray neutrons. That background was minimized by performing experiments underground (at the depth of 100 meters), by surrounding detectors with layers of additional absorbers and by using an electronic method of partial rejection of neutrons coming from the outside of the experimental setup. In a typical experiment, lasting several hours, the counting rate was about 8 per hour while the background was close to 2 counts per hour. Correcting such raw data for efficiency, and subtracting the background, the counting rate could be as high as 60 neutrons per hour.Counting nuclear particles at a rate which is only four times higher than the background would not prevent one from measuring the net counting rate very accurately if sufficiently long periods of time, for example, several days or weeks, were available. Unfortunately such luxury is not yet available when particles are emitted from metallic foils loaded with deuterium. Conditions favoring nuclear processes have not yet been identified but, according to experimental data, they often disappear after a couple of hours or so. Two methods of creating favorable conditions were used by Jones and his collaborators. The first method consisted of placing hot titanium foils into deuterium gas, the second consisted of treating foils with a weak D2O solution of the unusual sulfuric acid, D2SO4. Not every treatment resulted in creating a nuclear active environment, the rate of success, as far as the emission of neutrons is concerned, was about 40%. In my opinion, this fact should not be used as an argument against cold fusion. Further progress can be very fast when a team of highly trained scientists is already able to observe a new phenomenon in one out of two or three experiments. Something significant is still not under their control and additional research is necessary.2) The second paper presented by Jones and his coworkers described experiments with charged particles. In one experiment such particles, identified as 2.6 MeV protons, were counted at the rate of 2,171 ± 93 counts/hour. This was 400 times higher than the background and the repeatability was as high as 70%. Low energy protons, as described in item #28 (at my cold fusion web site), have already been reported by Lipson and his coworkers. The method of detection used by Lipson was based CR-39 track detectors while the method used by Jones was based on scintillation and silicon detectors. What can be more trustworthy than observation of protons by two teams of highly qualified scientists working in different laboratories and using different experimental techniques? Why are these experimental data ignored by those who keep repeating that cold fusion is voodoo science? The arguments used by them are based on what was known 13 years ago, not on knowledge accumulated in the last ten years. The authors claim the “repeatability” exceeding 70%. I suppose that it means that nuclear particles are not always emitted from thin titanium foils loaded with deuterium. Why is it so? Because something is still not under control of experimentalists. But being successful 70% of time is very significant, considering the absence of a theory. Keep in mind that Jones’s papers are downloadable from the above web site; my purpose is to summarize them, and to comment.3) The third paper of Jones and Ellsworth, downloadable from the LERN_CANR.ORG web site, is very different from the first two. I would call it a vision paper; it focuses on old speculations of great importance to planetary science and on anticipated research in that area. Here is how the essential hypothesis was formulated by the authors. “Natural geo-fusion in the earth occurs in or near the core of the earth, in the hot, hydrogen-bearing metals and minerals which are subjected to extreme off-equilibrium conditions deep in the earth. This hypothesis can be tested by measuring tritium and helium-3 in magmatic fluids from hot-spot volcanoes which tap magmas from plumes arising from the core-mantle boundary. In particular, magmatic waters of Kilauea, Loihi, and Icelandic volcanoes are predicted to contain significant tritium. We predict that tritium is also present in Jupiter, originating from ‘cold’ fusion in or near its metallic hydrogen core.” In the second part of their short paper, the authors speculate that cold fusion might play an important role in nucleosynthesis of elements. Nuclear transmutations, reported by many cold fusion scientists, give credence to such speculations. The article ends with a list of sophisticated analytical tools available to the Department of Physics and Astronomy of Brigham Young University; Steven Jones is a professor in that department. I suppose these tools will soon be used to expand current investigations of new nuclear phenomena. Let me end with another quote from this article; it illustrates a healthy attitude of cold fusion scientists toward research.. “Neither cold fusion nor cold nucleosynthesis is understood at present, nor are the results yet widely accepted by the scientific community. But as we continue to explore together, cooperative experiments at several laboratories giving positive results cannot be ignored much longer.” I hope the authors are right and that the entire field will soon be recognized as a valid area of useful research.Return to the clickable list of items
"Calculations show that more than enough deuterium finds its way into the upper mantle by this route (seawater in subduction zones) to account for the heat emitted by the Earth's core, although the heat obviously comes from other sources as well. The rate of fusion of deuterium nuclei required to produce the observed rations of helium-3 to helium-4 in rocks, diamonds and metals is similar to that observed by Jones in his experiments with electrolytes. Tritium can also be a product of the fusion of deuterium. Jones and his group say that the tritium detected in the gases from volcanoes is further evidence of cold fusion."
Another part of the puzzle regarding non-disclosure may have to do with world finances. Gold is mentioned briefly in Biological Transmutations. Almost all placer gold dust is pitted like a tiny piece of coral. A cubic mile of ocean water has as much gold suspended in it as all the bank vault in the world and it is extremely hard to extract. Hardrock gold veins are ribbons of pure gold at specific gravity 19.3 locked into quartz at specific gravity 2.7. If the gold was deposited in the quartz by magmatic intrusion it would not be suspended in the quartz, it would be in a puddle beneath it. Ask a scientist, any scientist, why there is no lead, mercury or other neuro-toxic elements in the world's ocean? There is none not even at parts per trillion unless a mining concern dumped it. If there were neuro-toxins in the oceans we would not be able to eat tuna (If you eat tuna). For billions of years lead has been leached into the oceans and a bacterium dating back 3 billion years has been eating it and changing it to gold. In British Columbia all gold panning has been on rivers downstream from lead-zinc ore bodies. There has never been an exposed gold ore body as the source of the placer gold dust and nuggets. Gold panning the Yukon River from its mouth led to the giant lead-zinc ore body in Faro, Yukon Territory. The South African hardrock quartz/gold vein is a metamorphized river bottom dating back over a billion years ago. Gold is a biological inert byproduct. It is as if the planet itself billions of years ago determined to make itself free of neuro-toxins in order to support life in the oceans and on land. Without that ancient bacteria there would not be no higher forms of life
Case #6 (Life on Mars):This is a case where an experiment performed on Mars (Viking Lander, 1976) indicated presence of organic molecules. The discovery made by Gilbert Levin was not recognized as a proof. “Almost all the mission scientists erred on the side of caution and declared Viking's discovery a false positive. But was it? The arguments continue to rage, but results from NASA's latest rovers show that the surface of Mars was almost certainly wet in the past and therefore hospitable to life. And there is plenty more evidence where that came from, Levin says. ‘Every mission to Mars has produced evidence supporting my conclusion. None has contradicted it’. " But not contradicting is not the same thing as confirming. The original experiment was not replicated during later missions.
Case #7 (polyneutrons):At the last cold fusion conference (ICCF11) I learned about a suggested theory of cold fusion. That theory of John Fisher was described in item #191. The description, however, does not reflect recent modifications. Several days ago John wrote to me about the new version of the theory; it will be described in an upcoming conference in Italy. A new attempt to identify a polyneutron is apparently in progress in France
Case #9 (Dark energy):The article claims that dark energy (a property of empty space) the most contradictory problem in physics. “In 1998, astronomers discovered that the universe is expanding at ever faster speeds. It's an effect still searching for a cause - until then, everyone thought the universe's expansion was slowing down after the big bang. Theorists are still floundering around, looking for a sensible explanation, .
Case #12 (light from distant quasars):Light emitted 12 billion years ago, and analyzed by spectroscopists on earth was found to contain peaks due to absorption in atoms scattered in the universe. But locations of peaks seems to be shifted with respect to where they are on earth. That is what was discovered in 1997 by an Australian astronomer, John Web. But French astronomers, headed by Patrick Petitjean, failed to confirm this observation. The team is now conducting a new experiment to validate the data. What can be a better illustration of how controversies should always be resolved in science? But progress is not easy. “The more we look at these new data, the more difficulties we see’ wrote another team member, Michael Murphy.
Case #13 (cold fusion):“After 16 years, it's back. In fact, cold fusion never really went away. Over a 10-year period from 1989, US navy labs ran more than 200 experiments to investigate whether nuclear reactions generating more energy than they consume . . . With controllable cold fusion, many of the world's energy problems would melt away: no wonder the US Department of Energy is interested. In December, after a lengthy review of the evidence, it said it was open to receiving proposals for new cold fusion experiments.That's quite a turnaround. The DoE's first report on the subject, published 15 years ago, concluded that the original cold fusion results . . . were impossible to reproduce, and thus probably false. . . . The snag is that fusion at room temperature is deemed impossible by every accepted scientific theory.” Validation of experimental facts should be based on better experiments. Science has been highly successful because it is characterized by unity between theoretical models and experimental data. The principle, as somebody wrote, is that theories guide but experiments decide. In science, unlike in mathematics, validity of theoretical models is based on experiments. Unfortunately, as illustrated in unit # 206, the DoE does not seem to be open to support research in the area of cold fusion.
The Search for Origins For millenia human-kind has wondered if we are alone in the Universe. Astrophysical and biological considerations, of the kind depicted below, lead to the strong suggestion that we are not alone as nothing unique can be identified with the formation of our Solar System and the development of life on this planet with its liquid surface.
Here is what you can consider to be the UO Astronomer official statement on this Asteroid hysteria: In early December 1997, Astronomers discovered a fast moving small asteroid. After 90 days of analyzing the orbit, it has been determined that this asteroid will have a near-earth encounter in 30 years. It is traditional that every new asteroid which is discovered has an error ellipse associated with its orbit that includes the earth. Hence, any time an asteroid is initially discovered, one can make the statement that there is some probability that it will impact the earth. A 90 day window in which to determine a 30 year orbit is an insufficient time to determine an accurate orbit and it is somewhat irresponsible science to do this and then issue a press release. This is similar to the cold fusion event of 1989. The discovery of this asteroid is a triumph for new telescope and detector technology that is surveying the Solar System for small debris. Small objects like this are likely to be common and have simply escaped detection (and impacting the earth) for centuries, but that doesn't mean they aren't there. Currently there is grossly insufficient data to determine with any precision the orbit of this newly discovered object. Doubtless it will pass between the Earth and the Moon, as other objects have previously done. More years of monitoring will better establish whether its time to panic or not. If panic is warranted, perhaps we need to move here:
Abstract:Gold ores worldwide in 1974 averaged 0.15 ounces troy per ton. By 1986 that average had dropped to 0.05 ounces per ton. As the concentration of these minable continental ores continues to diminish, the seas have increasingly become the object of exploration and research into gold reserves. Significant quantities of gold have been mined from ocean beach placers, and mid-oceanic ridges have yielded rich gold ore samples, but the greatest accessible reserve is the ocean itself. Seawater contains vast quantities of dissolved gold, perhaps as much as 10 trillion dollars (US) worth, though in dilute concentrations. Recent evidence suggests that much of the earths continental gold deposits have biological origins. Certain bacteria are believed to have been involved in the precipitation of gold out of dilute hydrothermal solutions. A possible avenue for commercially viable gold recovery from seawater might involve such a bacterium, or a specifically engineered microbe.
Gold nanoparticles show potential for noninvasive cancer treatmentOctober 10, 2005Researchers from the University of California, San Francisco and Georgia Institute of Technology have found a new way to kill cancer cells. Building on their previous work that used gold nanoparticles to detect cancer, they now are heating the particles and using them as agents to destroy malignant cells.The researchers are a father and son, working together on opposite coasts. Their study findings are reported in the on-line edition of the journal Cancer Letters, found at Sciencedirect.com (quicksearch: El-Sayed nanoparticles).
--------------------------------------------------------------------------------Gold from the Sea --------------------------------------------------------------------------------Written by Timothy McNultyCopyright 1994AbstractIntroductionDiscussionConclusionArticles citedAbstract:Gold ores worldwide in 1974 averaged 0.15 ounces troy per ton. By 1986 that average had dropped to 0.05 ounces per ton. As the concentration of these minable continental ores continues to diminish, the seas have increasingly become the object of exploration and research into gold reserves. Significant quantities of gold have been mined from ocean beach placers, and mid-oceanic ridges have yielded rich gold ore samples, but the greatest accessible reserve is the ocean itself. Seawater contains vast quantities of dissolved gold, perhaps as much as 10 trillion dollars (US) worth, though in dilute concentrations. Recent evidence suggests that much of the earths continental gold deposits have biological origins. Certain bacteria are believed to have been involved in the precipitation of gold out of dilute hydrothermal solutions. A possible avenue for commercially viable gold recovery from seawater might involve such a bacterium, or a specifically engineered microbe. Introduction:Humankind seems spellbound when confronted with gold. It is a soft and ductile metal and probably had very little utility to the peoples of the ancient world, but it was prized and sought after none the less. What seems most remarkable is that gold's value has not suffered as the world's currencies of the twentieth century have gone on to other standards. Perhaps gold's most valuable quality then, is its beauty (Weast 1980). Though probably not the first metal to be gathered from the earth, evidence suggests that gold was first mined at least 6000 years ago. It has been a standard of barter and exchange for at least 4000 years. Nearly all of Earth's civilizations have prized it, and yet it is quite rare. Estimates of gold's abundance range from 3 to 6 ppb (parts per billion) in the Earth's crust (Simon 1973, Lucas 1985). That is equivalent to about 1 gram of gold in 275 tons of rock. Much of the gold that has been mined over the course of human history has come from rocks rich with veins of the metal, or panned from the alluvial beds of steams and rivers. As these easily accessible sources become increasingly rare, gold mining has shifted to bulk ores of lesser grades. About 60% of the world's known gold reserves are in the Republic of Sough Africa and the next largest reserves are in Russia (Minerals Yearbook 1985). As the gold of the Earth's continents continues to become more scarce, both dreamers and scientists have been exploring the seas for this noble metal. Discussion:Seawater contains gold in solution. The English chemist, S. Sonstadt, was the first to definitely establish its presence in 1872. Even today, though, precise measurements of its concentration are highly controversial. Owing to gold's extreme dilution, many factors confound its experimental measurement, such as the necessity for ultra pure reagents, gold's affinity for and absorption into the walls of the experimental glassware, and gold's tendency to precipitate out of solution during transportation or preservation (Burk 1989). Though some of the earlier investigations, prior to 1960, have yielded wildly varied values, as high as 4000 ppt (parts per trillion) (Putman 1953), subsequent efforts have been more consistent. When considering only the data gathered since 1980, reported values for the concentration of gold in seawater have ranged from 5 to 50 ppt (Lucas 1985), with the average concentration at about 13 ppt. Some of the highest concentrations recently reported have come from seawater samples taken from the Bering Sea at 50 ppt (Pashkova 1988).Perhaps the higher concentrations of gold found in the Bering Sea can be attributed to the gold rich rivers of Alaska and Siberia that flow into the Bering Sea. Though the oceans of the Earth are mostly homogenous in the concentrations of dissolved minerals and trace elements, it is reasonable to believe that the effluence of gold-rich rivers may be at least partly responsible for the variability of concentrations. The gold concentration of some rivers has been measured in the low 1000's of ppt, and gold's actual solubility limit is about 4000 ppt at 23o C at a 1.8% concentration of chloride ions (Wood 1971). The reason why gold is found in such low concentrations relative to that of a saturated aqueous solution has to do with several natural processes, such as the action of biological scavengers which accumulate gold, the adsorption of gold on clay particles and sediments, and the adsorption of gold by high molecular weight organic matter present in seawater (Krauskopf 1956, Wood 1971, Burk 1989). This might also help explain the higher concentration of gold measured in the polar seas where the abundance of sedimentary deposits of microorganisms is less. Seawater is not the only source of gold from the sea. As previously mentioned, the continental rivers can carry huge quantities of gold to the sea, and not all of it is dissolved or in colloidal solution. The erosive forces of wind, water, and ice can strip the continental rocks of its gold and carry it to the sea. The estuaries and ocean beaches near the mouths of these rivers can and have been commercially exploited. In the region of the Stuart Peninsula of Alaska, the Yukon, Kobuk, and Noatak Rivers pour into Norton and Kotzebue Sounds carrying their gold laden alluvial sands and gravels. By 1898, gold prospectors working the rich placer deposits of the Yukon River and its tributaries had arrived at Anvil Creek near Nome. The ocean beaches within a few miles of Nome yielded the most gold to have yet been mined from the sea. By 1904, nearly 250,000 ounces of gold had been panned and sluiced from the beaches. In October of 1904, two men working a rocker near the mouth of Little Creek recovered in seven hours more than 2,400 ounces of gold (MaClaren 1908, Brooks 1905). Gold is still being profitably mined and dredged from these beaches and more ancient beach gravels in the area of the Stuard Peninsula. Profitable gold beach placers are not limited to Alaska. For instance, the beaches near the mouth of the San Lorenzo River in Santa Cruz, California, were mined periodically during the 1930's when the Great Depression forced many out-of-work Americans into the gold fields of California. It was reported that two men working a sluice could recover an ounce of gold per day when the first miners arrived at the Santa Cruz beaches. Within a year or two the gold had been depleted sufficiently so that only after a large Winter storm, when much of the sands were stripped away revealing the richer sands closer to bedrock, were the beaches again profitable. Some gold ores are associated the Phanerozoic ocean strata. These strata are believed to have been laid down on the ocean floors during periods of deep sea anoxia (Keith 1982, Spencer 1991). Most of these deposits are associated with the passive-margin environments of the lower Paleozoic and the upper Mesozoic eras. Since these strata and anoxia events are also associated with periods of high ocean levels, it is believed that oxygen the minimum zone, currently between at 500 to 1000 meters in depth, extended to the deep seafloors. It is believed that the increase in global temperatures and sea levels at these times interrupted the deep currents that carry the cold oxygen rich currents from the polar regions down to circulate around the ocean basins. The lack of oxygen in the deep ocean caused an enrichment of the sulfide elements and minerals associated with ocean volcanic activity (Spencer 1991). Other areas of the oceans have recently been explored for the possibility of profitable gold ores. Much discussion and many proposals of late have focused on the mining of iron-manganese nodules of the deep sea floor sediments. Some of these have yielded gold concentrations in the range of 1 to 11ppm (parts per million) (Baturin 1988, Burk 1989). Such a concentration of gold is almost twice the average grade of ore mined from the Earth's continents in 1986 (Dworetzky 1988), and yet for these iron-manganese nodules, their gold content is a minor consideration given the much more valuable concentrations of manganese and selenium. However, owing to the cost of recovering and processing these nodules, no commercially viable mining operation is yet in operation, even though several such operations are planed and much research and even a few small scale tests have been conducted. Gold ores have also been located along the mid-ocean ridges of the Atlantic and Pacific Oceans. One such deposit was found in association with the TAG hydrothermal field at 26o North latitude on the mid-Atlantic Ridge at the 3,670 meter water depth (Herzig 1991). The gold ores in these locations are associated with sulfide deposits formed by hydrothermal vents. These vents occur when the spreading seafloor allows water to percolate down in the crustal rocks and reach hot regions deep beneath the seafloor. The heated seawater dissolves mineral in much higher concentrations than can occur in cold water. From the spreading crustal plates the water dissolves various mineral and metals, such as sulfur, iron, copper, among others. Gold and silver are also dissolved but in very small concentrations. From samples of these hot solutions taken from the Sea Cliff hydrothermal field, on the northern Gorda Ridge, gold concentration ranges between 1 and 11ppb, and silver between 14 and 200 ppb (Zierenberg 1990). Temperatures of these solutions range from 100 to 350 deg C. Upon reaching the cold seafloor waters, much of the dissolved minerals and metals precipitate out of solution forming chimney-like vent structures. These chimneys build up and eventually fall over to form again. After enough time has passed, huge mounds of these structures form, being predominantly composed of iron and sulfide compounds. From the samples taken, gold concentrations ranged from 0.06 to 28.40 ppm. Similar, but ancient, sulfide deposits can be found in Australia, Cypress, and elsewhere. Many of these continental deposits have been commercially mined, but it was assumed that the recent oceanic deposits would not likely be of commercial grade because the evidence suggests that the continental deposits have gone through secondary concentration of the gold when ground water or surface weathering dissolves away much of the sulfide and iron matrix, leaving the deposits gold enriched (Herzig 1991). Though most of the mid-Atlantic Ridge sulfide deposits are of the lower grades that correlate to the virgin continental deposits, some, at least, appear to have undergone secondary concentration. It is theorized that this secondary concentration of gold occurs after the initial oxidation of the sulfide assemblages (0.8 to 5.5 ppm Au) and the percolation of the hydrothermal solutions redissolve and then redeposit the gold as pure native metal (at up to 23.0 ppm Au) (Herzig 1988). The discovery of this secondary concentration occurring at the bottom of the seas is important since geologists had previously assumed that sulfide gold ore deposits located on the continental plates would have had to have been exposed to weathering or ground water to be concentrated. It is now apparent that sulfide gold ore deposits may be found in previously unexplored regions. Much about the process of precipitation of gold and other metals from these solutions is unknown, however, it is believed that some sulfur-oxidizing bacteria of the genera Beggiatoa, Thiothrix or Thiovulum play an active role in this precipitation (Zierenberg 1990).These chemosynthetic bacteria derive energy unlike their surface dwelling relatives (assuming that they are related). Instead of deriving energy from the oxidation of organic mater, or from photosyntheses, they oxidize sulfide compounds directly from the scorching hot hydrothermal liquids. How these bacteria can live and even thrive at 200o C is a matter of much discussion and investigation, but evidence suggest that these bacteria can efficiently remove gold, silver, copper, and other metals and minerals from dilute aqueous solutions. Proposed methods for this deposition vary. One such method involves the increase in pH in the micro-environment of the microbial mats that line these vent chimneys. These metals are less soluble at the higher pH's and precipitate out of solution and are then stored within the cell walls (Mullen 1989). Other theories have been proposed regarding the role of gold precipitation from ore solutions by bacteria. Recent evidence suggests that most of the placer gold found in Alaska originated from bacterial scavenging. An analysis of the microstructure of Alaskan placer gold, and that of many of the epithermal deposits around the world, has revealed a fine structure of nearly pure gold microtubuals approximately 1 micrometer in diameter. It has been proposed that these hollow gold structures are the exact shape and size of the cellwall of bacterium genus Pedomicrobia (Watterson 1992). These bacteria are believed to derive energy from the precipitation of gold around themselves. A close examination of the microtubuals reveals branching structures of smaller diameters connected to the larger diameters. This observation is remarkable similar to the observed method of reproduction for Pedomicrobia. Instead of reproducing my fission, the splitting of the cell in two, these bacteria often reproduce by budding, a process remarkable similar in appearance to the gold microtubuals (Rennie 1992). The gold casings around the Pedomicrobia are extraordinary because of their high degree of purity, in excess of 98% gold (Pain 1988). It has been argued by these researchers that much of the Earth's placer gold deposits, have originated from similar biological processes with these or other bacteria. It is believed that the bacteria can concentrate the gold around themselves in such massive amounts because of an electrochemical reaction whereby the gold is gathered on pecifically adapted membrane receptors to which the bacteria discharges excess electrons from its biological processesthus precipitating the gold out of solution (Watterson 1992). The possibility that certain bacteria can concentrate gold in amounts sufficient to comprise a major share of the Earth's gold ores suggest that with the right application, these or similar bacteria may be employed in the extraction of gold from low grade deposits or solutions. Already, there are commercial applications of bacteria in the mining of gold. Specifically, the bacteria Bacillus cereus is being used by the Canadian Genprobe Company to increase the yield of gold from pyrite ores (Anonymous 1989). In this case the bacteria are after the pyrite matrix that binds the gold and prevents economic recovery otherwise. Bacterial processing of these pyrite ores is relatively inexpensive and has increased yields from an average of about 65% to as much as 96% (Dworetzky 1988). Given the affinity that some bacteria have for the concentration of gold, the question arises as to whether it might be feasible to employ such a bacterium, or one specifically engineered for the task, to scavenge gold directly from the dilute concentrations present in sea water. Conclusion:Even at the conservative estimates of 10 ppb of gold in seawater, there is a great deal of gold in solution in the oceans. Humankind has unearthed perhaps a total of 3.3 billion ounces of gold over the course of history, an amount equivalent To a cube of gold 55 feet on a side (Dworetzky 1988), but the sea water of the Earth's oceans contain about 25 billion ounces of gold (Burk 1989). If the ability of some of these bacteria to concentrate gold around their cell membranes to the degree that they form massively dense agglomerations of hollow gold microtubuals, as the evidence suggests, then perhaps a similar bacterium may find a practical application in sea water. It is believed that these bacteria concentrated gold from solution concentrations similar to that of sea water, though perhaps not similar with regard to other constituents. If such a bacterium could be identified and grown in sufficient amounts, it might then be fixed to substrates that could then either be moved through large volumes of sea water, or placed in stationary positions in areas of relatively swift currents. Once enough time had elapsed for these bacteria to gather sufficient amounts of gold, these substrates could then be gathered and processed to recover the gold. The problems in these approaches are not trivial, and the work and research needed for an evaluation of its practicality are not simple. I believe that such research might pursue exploring the precise biochemical and bioelectrical pathways for the deposition of gold in these naturally occurring bacteria. Perhaps with a sufficient understanding of these pathways, these gold scavenging abilities might be artificially promoted or enhanced sufficiently to achieve an economic recovery of gold from sea water.
Opportunity's microscopic imager resolves laminations in layers from Endurance Crater. These layers lie below the rock unit at Eagle Crater. Images suggest that the force at work here was wind, not water. NASA / JPL / Cornell [larger image]
Page created in 0.355 seconds with 28 queries.