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Nelson Eby1, Robert Hermes2, Norman Charnley3 & John A. Smoliga4 University of Massachusetts, Low... more Nelson Eby1, Robert Hermes2, Norman Charnley3 & John A. Smoliga4 University of Massachusetts, Lowell, Massachusetts, USA (Nelson_Eby@uml.edu), Los Alamos National Laboratory, New Mexico, USA, University of Oxford, Oxford, UK, Roxbury, Connecticut, USA On 16 July 1945, the first atomic bomb was detonated at the Alamogordo Bombing range in New Mexico, USA. Swept up into the nuclear cloud was the surrounding desert sand, which melted to form a green glassy material called ‘trinitite’. Contained within the glass are melted bits of the first atomic bomb and the support structures and various radionuclides formed during the detonation. The glass itself is marvelously complex at the tens to hundreds of micrometre scale, and besides glasses of varying composition also contains unmelted quartz grains. Air transport of the melted material led to the formation of spheres and dumbbell shaped glass particles. Similar glasses are formed during all ground level nuclear detonations and contain fore...

ABSTRACT Zinc mining first began in the Franklin, New Jersey, area in the 1700’s. In the late 180... more ABSTRACT Zinc mining first began in the Franklin, New Jersey, area in the 1700’s. In the late 1800’s the individual claims were consolidated into a single entity known as the New Jersey Zinc Company. The two mining operations were at Sterling Hill and Franklin Furnace. The major ore minerals were franklinite [(Zn,Mn2+,Fe2+)(Fe3+,Mn3+)2O4], willemite [Zn2SiO4], and zincite [(Zn,Mn2+)O]. These two mines are well-known to mineral collectors the world over as more than 300 different mineral species, including ~90 fluorescent minerals, have been identified at the two mines. In 1898 New Jersey Zinc built a smelter (West plant) at what became Palmerton, PA (named after Palmer, the president of New Jersey Zinc) and in 1911 a second smelter (East plant) was built. Smelting operations continued at these two plants until 1980. Ores from both mines were processed in Palmerton, but after 1954 (when the Franklin Furnace mine closed) only ores from Sterling Hill were processed in Palmerton. When operating, it was estimated that the smelters emitted 47 tons/yr of Cd, 95 tons/yr Pb, and 3,575 tons/yr Zn plus significant amounts of sulfur dioxide. The site of the abandoned smelters is now an EPA (Environmental Protection Agency) superfund site. A tree ring core was extracted from an oak tree approximately 2 km downwind from the zinc smelters. The core encompasses approximately 150 years of history starting in 1860. Ten segments of this core (ranging in mass from 167 to 351 mg) were analyzed for 25 elements using Instrumental Neutron Activation Analysis (INAA). This is the method of choice in this case because (1) it obviates the problem of obtaining a complete solution which is required by solution methods, (2) its high sensitivity for a number of the elements of interest, and (3) it is nondestructive (the same samples were subsequently used for a stable isotope study). Metals can be delivered to the tree either by deposition on the leaves or by cycling of the metals through the soil-root system. The metals are subsequently incorporated into the tree and are lodged in the ring wood. The data from the tree ring sequence reveal the following (1) by 2005 for most metals the concentration had returned to pre-smelter values, (2) Au and Co increased throughout the period of smelter operation, (3) Se, Sb, As, Sc, and U values increased from the time that smelter operations started until around 1950 when their concentrations began to decline, perhaps a response to the suspension of smelting of the Franklin Furnace ores, (4) Na and Zn concentrations remained relatively constant, and (5) K concentration declined throughout the period of smelter operation, which may reflect the loss of K due to acid deposition. Thus, the tree rings record the history of smelter operations and reflect the impact of the contaminants on the tree.

1 Geokimia Lingkungan Principles of Environmental Geochemistry By G Nelson Eby, 2004

ABSTRACT Since the inception of the term A-type by Loiselle and Wones (1979), this class of grani... more ABSTRACT Since the inception of the term A-type by Loiselle and Wones (1979), this class of granitoids has proven to be the most controversial and least understood member of the granitoid alphabet soup. Eby (1990, 1992) suggested that there were a variety of granitoids that fell within the A-type classification and that there were multiple petrogenetic pathways that could lead to rocks that met the largely chemical definition of A-type granitoids. The A1-type (often referred to as anorogenic) was a distinct group that had characteristics of magma derived from an OIB source and was inferred to be the fractionation product of an OIB-like basalt magma. The A2-type (often referred to as post-collisional or post-orogenic) represented all A-type granitoids not derived by fractionation of an OIB-like magma. These granitoids were generally emplaced shortly after an orogenic period and may have originated by melting of mantle material with crustal interaction or solely by the melting of crustal material. The North Nyasa and Chilwa alkaline provinces of Malawi and the White Mountain igneous province of the northeastern US are classic examples of A1-type magmatic provinces. An extreme range of lithologies is found in all three provinces from carbonatites through a variety of both silica-undersaturated and silica over-saturated silicate rocks to alkali granites. Trace element and isotopic data indicate that an OIB-source is an important component in the magmatic history. The White Mountain province is an instructive example. Two periods of A-type magmatism are recognized in this province, the older from 200 to 160 Ma and the younger confined to a narrow time interval centered around 123 Ma. The older White Mountain series essentially consists of silica-saturated felsic (syenite to alkali granite) igneous rocks. Mafic rocks are only significant in the Pliny Range. Nepheline-bearing syenites are found at Red Hill and Rattlesnake, indicating that silica-undersaturated magmas were present at the time the silica-saturated sequences were emplaced. Detailed studies of the largest unit in the series, the White Mountain batholith, suggest that all the igneous rock groups (syenites, metaluminous granties, peralkaline granites and rhyolites) can be related through variable interactions of mantle-derived melts with the subcontinental lithosphere. The younger White Mountain series and the temporally and spatially related Monteregian Hills province of Quebec, Canada, shows the extreme range of lithologies often typical of the A1-type association. Mafic rocks are significant in these two provinces and basalts and rhyolites are found in several intrusions. Based on trace element and isotopic chemistry, a successful model for the origin of the various lithologies involves various degrees of partial melting of a garnet lherzolite source (depleted mantle based on isotopic characteristics) and subsequent variable interaction of the basaltic magmas with the continental crust. An example of an A2-type province is the Jurassic granitoids and associated bi-modal volcanics of southern China. These sequences were emplaced in a rift structure that developed shortly after continent-continent collision. The basaltic magmas are continental tholeiites and the rhyolites and the granites apparently formed by differentiation of the basaltic magmas with some crustal contamination. It is suggested that A-type granitoids can form via three different petrogenetic pathways. The A1-types form by differentiation of a basaltic magma, with variable degrees of crustal contamination, derived from an OIB-like source. The A2-types form either by differentiation of a continental tholeiite, with variable degrees of crustal interaction, or by direct melting of a crustal source that had gone through a previous melting episode. The challenge, in the case of the A2-types, is determine which of these pathways was followed by a particular granitoid.

Journal of the Geological Society of India, 1990

ABSTRACT A-type granites are emplaced in either within plate anorogenic settings or in the final ... more ABSTRACT A-type granites are emplaced in either within plate anorogenic settings or in the final stages of an orogenic event (sometimes referred to as post-orogenic). The universal commonality is that the tectonic environment has become extensional and the granites do not show any tectonic fabric (although such fabric may be introduced by later tectonic events). In a number of provinces A-type granites are associated in space and time with silica-undersaturated lithologies. In some cases, mafic rocks are closely associated with the A-type granites. The A-type granites have been characterized chemically in terms of their Ga/Al ratio versus a variety of trace and major elements and they plot in the Within Plate Granite fields on tectonic discriminant diagrams. They range from peraluminous to peralkaline in composition. In primitive mantle normalized plots they generally show significant enrichment in Cs and Rb, significant depletion in Ba, Sr, Eu, Ti, and P, and no or minor Nb and Ta depletion. Chondrite normalized REE plots are variable from relatively flat patterns with large negative Eu anomalies to more LREE enriched patterns with relatively small Eu anomalies. In most cases the isotopic data indicate mantle involvement. Given the variable settings and associated lithologies, one petrogenetic model cannot be used to explain the origin of A-type granites. The 130 – 120 Ma Chilwa alkaline province is located at the southern end of the current day East African Rift system. Magmatic activity started with the eruption of basanitic lavas followed a few million years later by the emplacement of nepheline syenites, syenites, granites, and carbonatite. The sequence of emplacement is from silica undersaturated rocks to silica oversaturated rocks. Elemental and isotopic data indicate that the magmas were derived from an OIB-like mantle source. AFC processes led to the variety of felsic rock types seen in the province, with the most contaminated magmas yielding the granites. The White Mountain igneous province of the northeastern United States is comprised of a number of ring dike complexes and associated stock-like intrusions. The igneous activity occurred in two discrete time intervals – 190 to 160 Ma and ~122 Ma. The large intrusions of the older event are dominantly felsic and silica saturated while the generally smaller intrusions of the younger event have significant associated mafic rocks. The younger event is also time-correlative with the Monteregian Hills alkaline province of Quebec which shows the whole conceivable range of silica-undersaturated to silica over-saturated alkaline rock types. Elemental and isotopic data indicate an OIB-like source, with mafic magmas variably contaminated by crustal material. The Carboniferous granites of western Argentina were emplaced at the end of a long period of orogenesis and are related to a major shear zone. These granites are peraluminous to metaluminous and elemental and isotopic data indicate a subcontinental lithospheric mantle component, but the magmas were largely derived from the crust. The above examples indicate the variety of settings in which A-type granites can occur. In all cases there is evidence for a mantle component, although this component seems to be less significant in the case of post-orogenic granites.

Canadian Journal of Earth Sciences, 1990

The late Precambrian Coldbrook Group comprises basal basaltic flows and pyroclastic rocks, fragme... more The late Precambrian Coldbrook Group comprises basal basaltic flows and pyroclastic rocks, fragmental andesitic to rhyolitic rocks, and minor capping sedimentary strata, all deformed and metamorphosed to prehnite–pumpellyite grade. Sr-isotope data indicate metasomatism, and probably deformation and metamorphism, took place long after deposition, possibly during major Carboniferous deformation of the Bay of Fundy region. Geochemical data suggest that the Coldbrook Group formed in a subduction-related ensialic volcanic-arc environment, although some specimens appear transitional to within-plate tholeiites. Magma evolution was dominated by fractionation of ilmenite, pyroxene, and plagioclase. Trace-element ratios suggest crustal contamination of virtually all Coldbrook Group rocks, with the amount of crustal component larger in the more salic portion. Comparison of data for the Coldbrook Group with data of other late Precambrian volcanic sequences in Atlantic Canada suggests that simil...

Journal of the …, 1995

Journal of the Geological Society, London, Vol. 152, 1995, pp. 689-701, 11 figs, 4 tables. Printe... more Journal of the Geological Society, London, Vol. 152, 1995, pp. 689-701, 11 figs, 4 tables. Printed in Northern Ireland ... The Cretaceous Separation Point batholith, New Zealand: granitoid magmas ... 'Department of Geology, University of Canterbury, Private Bag 4800, Christchurch, ...

Journal of Volcanology …, 2007

New Zealand Journal of Geology and Geophysics

Ion microprobe U‐Pb zircon ages have been obtained from four samples of Cretaceous granitoid and ... more Ion microprobe U‐Pb zircon ages have been obtained from four samples of Cretaceous granitoid and two samples of volcanogenic sediment from the northwest Nelson‐Westland region of the South Island of New Zealand. Crow Granite, which intrudes lower Paleozoic metasedi‐mentary rocks in the Buller Terrane on the eastern side of the Karamea Batholith, has given a crystallisation age of 137 ±

New Zealand. Journal of …, 1998

Page 1. Reproduced with permission of the copyright owner. Further reproduction prohibited withou... more Page 1. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Geochronology and geochemistry of a Mesozoic magmatic arc system, Fiordland, ... RJ ...

Nelson Eby1, Robert Hermes2, Norman Charnley3 & John A. Smoliga4 University of Massachusetts, Low... more Nelson Eby1, Robert Hermes2, Norman Charnley3 & John A. Smoliga4 University of Massachusetts, Lowell, Massachusetts, USA (Nelson_Eby@uml.edu), Los Alamos National Laboratory, New Mexico, USA, University of Oxford, Oxford, UK, Roxbury, Connecticut, USA On 16 July 1945, the first atomic bomb was detonated at the Alamogordo Bombing range in New Mexico, USA. Swept up into the nuclear cloud was the surrounding desert sand, which melted to form a green glassy material called ‘trinitite’. Contained within the glass are melted bits of the first atomic bomb and the support structures and various radionuclides formed during the detonation. The glass itself is marvelously complex at the tens to hundreds of micrometre scale, and besides glasses of varying composition also contains unmelted quartz grains. Air transport of the melted material led to the formation of spheres and dumbbell shaped glass particles. Similar glasses are formed during all ground level nuclear detonations and contain fore...

ABSTRACT Zinc mining first began in the Franklin, New Jersey, area in the 1700’s. In the late 180... more ABSTRACT Zinc mining first began in the Franklin, New Jersey, area in the 1700’s. In the late 1800’s the individual claims were consolidated into a single entity known as the New Jersey Zinc Company. The two mining operations were at Sterling Hill and Franklin Furnace. The major ore minerals were franklinite [(Zn,Mn2+,Fe2+)(Fe3+,Mn3+)2O4], willemite [Zn2SiO4], and zincite [(Zn,Mn2+)O]. These two mines are well-known to mineral collectors the world over as more than 300 different mineral species, including ~90 fluorescent minerals, have been identified at the two mines. In 1898 New Jersey Zinc built a smelter (West plant) at what became Palmerton, PA (named after Palmer, the president of New Jersey Zinc) and in 1911 a second smelter (East plant) was built. Smelting operations continued at these two plants until 1980. Ores from both mines were processed in Palmerton, but after 1954 (when the Franklin Furnace mine closed) only ores from Sterling Hill were processed in Palmerton. When operating, it was estimated that the smelters emitted 47 tons/yr of Cd, 95 tons/yr Pb, and 3,575 tons/yr Zn plus significant amounts of sulfur dioxide. The site of the abandoned smelters is now an EPA (Environmental Protection Agency) superfund site. A tree ring core was extracted from an oak tree approximately 2 km downwind from the zinc smelters. The core encompasses approximately 150 years of history starting in 1860. Ten segments of this core (ranging in mass from 167 to 351 mg) were analyzed for 25 elements using Instrumental Neutron Activation Analysis (INAA). This is the method of choice in this case because (1) it obviates the problem of obtaining a complete solution which is required by solution methods, (2) its high sensitivity for a number of the elements of interest, and (3) it is nondestructive (the same samples were subsequently used for a stable isotope study). Metals can be delivered to the tree either by deposition on the leaves or by cycling of the metals through the soil-root system. The metals are subsequently incorporated into the tree and are lodged in the ring wood. The data from the tree ring sequence reveal the following (1) by 2005 for most metals the concentration had returned to pre-smelter values, (2) Au and Co increased throughout the period of smelter operation, (3) Se, Sb, As, Sc, and U values increased from the time that smelter operations started until around 1950 when their concentrations began to decline, perhaps a response to the suspension of smelting of the Franklin Furnace ores, (4) Na and Zn concentrations remained relatively constant, and (5) K concentration declined throughout the period of smelter operation, which may reflect the loss of K due to acid deposition. Thus, the tree rings record the history of smelter operations and reflect the impact of the contaminants on the tree.

1 Geokimia Lingkungan Principles of Environmental Geochemistry By G Nelson Eby, 2004

ABSTRACT Since the inception of the term A-type by Loiselle and Wones (1979), this class of grani... more ABSTRACT Since the inception of the term A-type by Loiselle and Wones (1979), this class of granitoids has proven to be the most controversial and least understood member of the granitoid alphabet soup. Eby (1990, 1992) suggested that there were a variety of granitoids that fell within the A-type classification and that there were multiple petrogenetic pathways that could lead to rocks that met the largely chemical definition of A-type granitoids. The A1-type (often referred to as anorogenic) was a distinct group that had characteristics of magma derived from an OIB source and was inferred to be the fractionation product of an OIB-like basalt magma. The A2-type (often referred to as post-collisional or post-orogenic) represented all A-type granitoids not derived by fractionation of an OIB-like magma. These granitoids were generally emplaced shortly after an orogenic period and may have originated by melting of mantle material with crustal interaction or solely by the melting of crustal material. The North Nyasa and Chilwa alkaline provinces of Malawi and the White Mountain igneous province of the northeastern US are classic examples of A1-type magmatic provinces. An extreme range of lithologies is found in all three provinces from carbonatites through a variety of both silica-undersaturated and silica over-saturated silicate rocks to alkali granites. Trace element and isotopic data indicate that an OIB-source is an important component in the magmatic history. The White Mountain province is an instructive example. Two periods of A-type magmatism are recognized in this province, the older from 200 to 160 Ma and the younger confined to a narrow time interval centered around 123 Ma. The older White Mountain series essentially consists of silica-saturated felsic (syenite to alkali granite) igneous rocks. Mafic rocks are only significant in the Pliny Range. Nepheline-bearing syenites are found at Red Hill and Rattlesnake, indicating that silica-undersaturated magmas were present at the time the silica-saturated sequences were emplaced. Detailed studies of the largest unit in the series, the White Mountain batholith, suggest that all the igneous rock groups (syenites, metaluminous granties, peralkaline granites and rhyolites) can be related through variable interactions of mantle-derived melts with the subcontinental lithosphere. The younger White Mountain series and the temporally and spatially related Monteregian Hills province of Quebec, Canada, shows the extreme range of lithologies often typical of the A1-type association. Mafic rocks are significant in these two provinces and basalts and rhyolites are found in several intrusions. Based on trace element and isotopic chemistry, a successful model for the origin of the various lithologies involves various degrees of partial melting of a garnet lherzolite source (depleted mantle based on isotopic characteristics) and subsequent variable interaction of the basaltic magmas with the continental crust. An example of an A2-type province is the Jurassic granitoids and associated bi-modal volcanics of southern China. These sequences were emplaced in a rift structure that developed shortly after continent-continent collision. The basaltic magmas are continental tholeiites and the rhyolites and the granites apparently formed by differentiation of the basaltic magmas with some crustal contamination. It is suggested that A-type granitoids can form via three different petrogenetic pathways. The A1-types form by differentiation of a basaltic magma, with variable degrees of crustal contamination, derived from an OIB-like source. The A2-types form either by differentiation of a continental tholeiite, with variable degrees of crustal interaction, or by direct melting of a crustal source that had gone through a previous melting episode. The challenge, in the case of the A2-types, is determine which of these pathways was followed by a particular granitoid.

Journal of the Geological Society of India, 1990

ABSTRACT A-type granites are emplaced in either within plate anorogenic settings or in the final ... more ABSTRACT A-type granites are emplaced in either within plate anorogenic settings or in the final stages of an orogenic event (sometimes referred to as post-orogenic). The universal commonality is that the tectonic environment has become extensional and the granites do not show any tectonic fabric (although such fabric may be introduced by later tectonic events). In a number of provinces A-type granites are associated in space and time with silica-undersaturated lithologies. In some cases, mafic rocks are closely associated with the A-type granites. The A-type granites have been characterized chemically in terms of their Ga/Al ratio versus a variety of trace and major elements and they plot in the Within Plate Granite fields on tectonic discriminant diagrams. They range from peraluminous to peralkaline in composition. In primitive mantle normalized plots they generally show significant enrichment in Cs and Rb, significant depletion in Ba, Sr, Eu, Ti, and P, and no or minor Nb and Ta depletion. Chondrite normalized REE plots are variable from relatively flat patterns with large negative Eu anomalies to more LREE enriched patterns with relatively small Eu anomalies. In most cases the isotopic data indicate mantle involvement. Given the variable settings and associated lithologies, one petrogenetic model cannot be used to explain the origin of A-type granites. The 130 – 120 Ma Chilwa alkaline province is located at the southern end of the current day East African Rift system. Magmatic activity started with the eruption of basanitic lavas followed a few million years later by the emplacement of nepheline syenites, syenites, granites, and carbonatite. The sequence of emplacement is from silica undersaturated rocks to silica oversaturated rocks. Elemental and isotopic data indicate that the magmas were derived from an OIB-like mantle source. AFC processes led to the variety of felsic rock types seen in the province, with the most contaminated magmas yielding the granites. The White Mountain igneous province of the northeastern United States is comprised of a number of ring dike complexes and associated stock-like intrusions. The igneous activity occurred in two discrete time intervals – 190 to 160 Ma and ~122 Ma. The large intrusions of the older event are dominantly felsic and silica saturated while the generally smaller intrusions of the younger event have significant associated mafic rocks. The younger event is also time-correlative with the Monteregian Hills alkaline province of Quebec which shows the whole conceivable range of silica-undersaturated to silica over-saturated alkaline rock types. Elemental and isotopic data indicate an OIB-like source, with mafic magmas variably contaminated by crustal material. The Carboniferous granites of western Argentina were emplaced at the end of a long period of orogenesis and are related to a major shear zone. These granites are peraluminous to metaluminous and elemental and isotopic data indicate a subcontinental lithospheric mantle component, but the magmas were largely derived from the crust. The above examples indicate the variety of settings in which A-type granites can occur. In all cases there is evidence for a mantle component, although this component seems to be less significant in the case of post-orogenic granites.

Canadian Journal of Earth Sciences, 1990

The late Precambrian Coldbrook Group comprises basal basaltic flows and pyroclastic rocks, fragme... more The late Precambrian Coldbrook Group comprises basal basaltic flows and pyroclastic rocks, fragmental andesitic to rhyolitic rocks, and minor capping sedimentary strata, all deformed and metamorphosed to prehnite–pumpellyite grade. Sr-isotope data indicate metasomatism, and probably deformation and metamorphism, took place long after deposition, possibly during major Carboniferous deformation of the Bay of Fundy region. Geochemical data suggest that the Coldbrook Group formed in a subduction-related ensialic volcanic-arc environment, although some specimens appear transitional to within-plate tholeiites. Magma evolution was dominated by fractionation of ilmenite, pyroxene, and plagioclase. Trace-element ratios suggest crustal contamination of virtually all Coldbrook Group rocks, with the amount of crustal component larger in the more salic portion. Comparison of data for the Coldbrook Group with data of other late Precambrian volcanic sequences in Atlantic Canada suggests that simil...

Journal of the …, 1995

Journal of the Geological Society, London, Vol. 152, 1995, pp. 689-701, 11 figs, 4 tables. Printe... more Journal of the Geological Society, London, Vol. 152, 1995, pp. 689-701, 11 figs, 4 tables. Printed in Northern Ireland ... The Cretaceous Separation Point batholith, New Zealand: granitoid magmas ... 'Department of Geology, University of Canterbury, Private Bag 4800, Christchurch, ...

Journal of Volcanology …, 2007

New Zealand Journal of Geology and Geophysics

Ion microprobe U‐Pb zircon ages have been obtained from four samples of Cretaceous granitoid and ... more Ion microprobe U‐Pb zircon ages have been obtained from four samples of Cretaceous granitoid and two samples of volcanogenic sediment from the northwest Nelson‐Westland region of the South Island of New Zealand. Crow Granite, which intrudes lower Paleozoic metasedi‐mentary rocks in the Buller Terrane on the eastern side of the Karamea Batholith, has given a crystallisation age of 137 ±

New Zealand. Journal of …, 1998

Page 1. Reproduced with permission of the copyright owner. Further reproduction prohibited withou... more Page 1. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Geochronology and geochemistry of a Mesozoic magmatic arc system, Fiordland, ... RJ ...

Fission-track ages have been determined for carbonatites and their associated alkaline rocks from... more Fission-track ages have been determined for carbonatites and their associated alkaline rocks from three geographic areas: the Parana Basin, Brazil and Paraguay; the Arkansas alkaline province, U.S.A.; and the Oka complex, Canada. Apatite ages were determined by the population method, and sphene ages using an external mica detector. Fluence was determined relative to NBS standard glass SRM962. Multiple age determinations were carried out for the same sample, and for samples from the same lithologic unit, in order to minimize experimental error. Using this approach it appears possible distinguish events that differ by as little as 5% in absolute age. In essentially all cases, apatite and sphene ages are concordant indicating a shallow depth of emplacement. This observation is in agreement with geologic inference. For both the Parana Basin and the Arkansas province there are a number of independent radiometric (largely conventional K-Ar) ages. A comparison between the different geochronologic techniques reveals that in the large majority of cases the fission-track ages agree within experimental error with the other independently determined ages. The results of these studies suggest that the fission-track method can yield precise results in thermally undisturbed rocks, and that repetitive analyses of samples may make it possible to distinguish between geologic events that differ by as little as 5% in absolute age.

ABSTRACT Conference title - Second international maar conference, Copyright - GeoRef, Copyright 2... more ABSTRACT Conference title - Second international maar conference, Copyright - GeoRef, Copyright 2012, American Geosciences Institute. Reference includes data supplied by Hungarian Geological Library, Budapest, Hungary, Date revised - 2009-01-01, Language of summary - English, Pages - 59, ProQuest ID - 50556381, SubjectsTermNotLitGenreText - boron; chemical composition; diatremes; igneous rocks; intrusions; maars; volcanic features; volcanic rocks, SuppNotes - Pieces: 107., Last updated - 2012-06-07, CODEN - #05177, docISBN - 9636712409, Corporate institution author - Gmeling, Katalin; Nemeth, Karoly; Martin, Ulrike; Eby, N, DOI - 2009-000424; 9636712409; #05177

The Atomic age began the morning of July 16, 1945, with the detonation of an atomic device (a plu... more The Atomic age began the morning of July 16, 1945, with the detonation of an atomic device (a plutonium bomb) near Socorro, New Mexico, USA. Almost seventy years later, with the advent of international terrorism, this event has led to significant research efforts on the characterization of the products of an atomic detonation with the intent to be able to identify the source of the material. Much of this work has focused on the glass (trinitite) produced during the first atomic bomb test, an ideal situation given that the source of the material in the glasses is either desert sand or metals directly associated with the bomb test (bomb casing, steel tower, lead bricks, copper wire). However, if an atomic device should ever be detonated in an urban area, characterization of the bomb materials will be greatly impeded by the large amount of material contributed by the local environment. Fission-track mapping, which provides the spatial distribution of the fissionable isotope(s) can be u...

A-type granites are emplaced in either within plate anorogenic settings or in the final stages of... more A-type granites are emplaced in either within plate anorogenic settings or in the final stages of an orogenic event (sometimes referred to as post-orogenic). The universal commonality is that the tectonic environment has become extensional and the granites do not show any tectonic fabric (although such fabric may be introduced by later tectonic events). In a number of provinces A-type granites are associated in space and time with silica-undersaturated lithologies. In some cases, mafic rocks are closely associated with the A-type granites. The A-type granites have been characterized chemically in terms of their Ga/Al ratio versus a variety of trace and major elements and they plot in the Within Plate Granite fields on tectonic discriminant diagrams. They range from peraluminous to peralkaline in composition. In primitive mantle normalized plots they generally show significant enrichment in Cs and Rb, significant depletion in Ba, Sr, Eu, Ti, and P, and no or minor Nb and Ta depletion...

International Journal of Radiation Applications and Instrumentation. Part D. Nuclear Tracks and Radiation Measurements, 1990

Alkaline rocks comprise a minor amount of the total volume of igneous rocks, but in terms of vari... more Alkaline rocks comprise a minor amount of the total volume of igneous rocks, but in terms of variety and complexity they have challenged petrologic thinking for decades. Alkaline magmatism is widely distributed both spatially and throughout geologic time. Most alkaline provinces show significant lithological diversity and classic examples of this diversity are the Chilwa Alkaline Province (CAP) of southern Malawi and the Monteregian Hills - White Mountain (MHWM) province of Quebec and New England. CAP magmatism started at ca 133 Ma and continued to ca 110 Ma. Initial magmatism was marked by the eruption of nephelinitic and basanitic magmas (now preserved as large enclaves in later syenite intrusions). Subsequent intrusions systematically progressed from silica undersaturated sodalite-nepheline syenites through syenites, and the igneous activity culminated with the emplacement of a large alkali granite body. Spatially related carbonatite magmatism occurred ca 126 Ma. Sr, Nd, and Pb i...

Zinc mining first began in the Franklin, New Jersey, area in the 1700’s. In the late 1800’s the i... more Zinc mining first began in the Franklin, New Jersey, area in the 1700’s. In the late 1800’s the individual claims were consolidated into a single entity known as the New Jersey Zinc Company. The two mining operations were at Sterling Hill and Franklin Furnace. The major ore minerals were franklinite [(Zn,Mn2+,Fe2+)(Fe3+,Mn3+)2O4], willemite [Zn2SiO4], and zincite [(Zn,Mn2+)O]. These two mines are well-known to mineral collectors the world over as more than 300 different mineral species, including ~90 fluorescent minerals, have been identified at the two mines. In 1898 New Jersey Zinc built a smelter (West plant) at what became Palmerton, PA (named after Palmer, the president of New Jersey Zinc) and in 1911 a second smelter (East plant) was built. Smelting operations continued at these two plants until 1980. Ores from both mines were processed in Palmerton, but after 1954 (when the Franklin Furnace mine closed) only ores from Sterling Hill were processed in Palmerton. When operating,...

Archean alkaline complexes (and carbonatites) are rare worldwide. Only a few tens complexes in th... more Archean alkaline complexes (and carbonatites) are rare worldwide. Only a few tens complexes in the Canadian Shield (Superior Province), Greenland, and Australia (Yilgarn craton) are known to date. They are composed of alkali and nepheline syenites, foidolites, carbonatites, peralkaline granites, lamprophyres, and potassic volcanic rocks. The age of the oldest alkaline rocks is estimated at 2.70-2.65 Ga. The Archaean alkaline complexes belong to the potassic series, the saturated and oversaturated rock series show sanukitoid affinities (i.e. they share geochemical characteristics with high-Mg andesites found in modern arc settings). The most of rocks are depleted in high field strength elements (HFSE) and enriched in some large ion lithophile (LILE) and compatible (Ba, Sr, Ni, Co, Cr) elements. Therefore, the geodynamic setting of the Archean alkaline rocks is interpreted as a subduction-related environment and the depleted mantle is thought to be their source. The Archean subduction...

The Keivy alkali granite complex consists of 2650-2660 Ma aegirine-arfvedsonite granites (six she... more The Keivy alkali granite complex consists of 2650-2660 Ma aegirine-arfvedsonite granites (six sheet-like massifs of a few hundred meters thickness and a total exposure area of ca. 2500 km2), 2670 Ma aegirine-augite-lepidomelane-ferrohastingsite syenogranites that occur in the margins of some massifs, and 2680 Ma lepidomelane-ferrohastingsite syenite dykes that intrude the TTG basement of the Central Kola terrane (NE Fennoscandian shield). Small dike-like bodies of 2610 Ma nepheline syenite cut the West Keivy alkali granite massif. On standard trace element discriminant diagrams (Whalen et al., 1987; Pearce et al., 1984; Eby, 1990) the Keivy alkali granites plot as within-plate or post-collisional A-type granitoids. The least evolved syenogranites plot in the EM2-field on the εSr - εNd diagram. The low Y/Nb and Yb/Ta ratios for the associated nepheline syenite indicate an OIB affinity. The rocks of the Keivy complex are extremely enriched in Zr (300-5000 ppm), Y (40-500 ppm), Nb (20-...

The Central Atlantic Magmatic Province (CAMP) extends approximately 5000 km north to south on bot... more The Central Atlantic Magmatic Province (CAMP) extends approximately 5000 km north to south on both sides of the Atlantic Ocean. The magmatic activity occurred at the Triassic-Jurassic boundary (~200 Ma). In New England and the Maritime provinces this magmatic event is represented by two major suites of Mesozoic dikes emplaced between 225 and 230 Ma (Coastal New England, CNE) and at ~200 Ma (CAMP). In New England the CAMP magmatism is immediately followed by the emplacement of a distinctly different suite of igneous rocks (the older White Mountain Igneous Province, OWM) between ~200 Ma and 160 Ma. In the Cretaceous (~122 Ma) a more diverse group of rocks, ranging from carbonatites to alkaline granites, here referred to as the Monteregian Hills White Mountain Igneous Province (MHWM), are emplaced in Quebec and New England. The OWM is dominated by feldspathic silica-saturated rocks (syenites, quartz syenites, and granites), but silica-undersaturated rocks are found at Red Hill and Ratt...

Granites are found in essentially all tectonic environments, are derived from a wide variety of s... more Granites are found in essentially all tectonic environments, are derived from a wide variety of sources, and evolve along multiple pathways. The classification of granites should be devoid of petrogenetic implications because the same mineralogical and textural outcomes can be achieved via different petrogenetic pathways. Various schemes used to classify granites and discriminant diagrams will be discussed and critiqued. The identification of the petrogenetic process responsible for a particular granite, and associated igneous rocks, is a continuing challenge in petrology. Granitic magmas may arise from direct melting of a variety of crustal source rocks, by differentiation of mantle derived melts, and via various magma mixing scenarios. Major and trace element geochemistry, stable and radiogenic isotopes, and geochronology utilizing both whole rocks and minerals, are used to unravel this history. This presentation will focus on granitoids formed in subduction and collision settings...

The Late Archean (2.6-2.8 Ga) is remarkable for the earliest manifestation of syenite-granodiorit... more The Late Archean (2.6-2.8 Ga) is remarkable for the earliest manifestation of syenite-granodiorite-granite magmatism of alkaline affinity. From the published data this magmatism can be related to either “sanukitoid” (subduction) or “A-type granitoid” (anorogenic) magmatism. Key examples from the Superior, Yilgarn, and Baltic shields were studied to discriminate their origin: 2680-2670 Ma alkaline granites, syenites and associated nepheline syenites of the Abitibi greenstone belt (Sutcliffe et al., 1990; Corfu et al., 1991); 2650-2630 Ma alkaline granites and syenites of the Eastern Goldfields granite-greenstone terrane (Libby, 1989; Smithies & Champion, 1999); and 2610-2680 Ma alkaline granites, syenogranites, and associated nepheline syenites of the Keivy complex of the Central Kola granite-greenstone domain (Mitrofanov et al., 2000; Zozulya et al., 2005). The first two examples consist of small (10-90 km2) stocks spatially and temporally associated with potassic volcanics and lamp...

A suite of massif-type anorthosites and peralkaline granites is found in the Archean Keivy terran... more A suite of massif-type anorthosites and peralkaline granites is found in the Archean Keivy terrane of the NE Baltic shield. The 2660-2680 Ma Keivy anorthosite complex consists of several large (up to the 170 km2) lopoliths composed mainly of anorthosite and gabbro-anorthosite and marginal gabbro-norite and titanomagnetite-rich troctolite bodies. The Keivy anorthosites have low REE abundances (Ce 5-23 and Yb 1.5-6.8 times chondrites), fractionated REE distributions (chondrite-normalized La/Yb ratios are 4-10) and positive Eu anomalies. The comagmatic gabbro-norites have similar REE patterns, but no or negligible positive Eu anomalies. The rocks show high compatible element (Sc, 25-40 ppm and Sr, 460-670 ppm) abundances. As the chondrite-normalized La/Yb ratios do not correlate with REE abundances, an enriched source for the primary magmas is proposed. The enriched source for the Keivy anorthosites has low Nd (-0.15 to -0.24) and low Y/Nb ratios (0.6-1.3). From the geochemical data i...

Archean alkaline complexes are extremely rare but are of particular interest because the magmas h... more Archean alkaline complexes are extremely rare but are of particular interest because the magmas have a mantle origin. Given their high Sr and Nd contents, crustal contamination has only a minor impact on the mantle-derived isotopic signatures. Therefore, they can provide valuable information on the isotopic composition of the subcontinental mantle and geodynamics in Archean. The previously reported Late Archean alkaline complexes (2.7-2.6 Ga) from the Canadian and Australian shields belong to the potassic series, are depleted in LIL and HFS elements, and are related to subduction, thereby forming in a compressive tectonic environment and having a depleted mantle source. The absence of Archean sodic alkaline complexes forming in extensional environments was mainly ascribed to the absence of metasomatic processes in the mantle and lower lithosphere (Blichert-Toft et al., 1996). Greenland Archean alkaline complexes (2698-2664 Ma syn- to post-kinematic pyroxenites, hornblendites, norite...

Forensic Geology can be used as a vehicle to introduce students to geological concepts and princi... more Forensic Geology can be used as a vehicle to introduce students to geological concepts and principles using an inquiry driven approach - i.e., crime solving. We have developed such a course largely based on case studies. The course was designed for non-science majors, but biology, chemistry, and physics majors have taken the course as a technical elective. The Case of the Sandy Body is an example of the approach we use in this course. The case starts with a body dumped in a classroom. The body is wrapped in cloth and there is abundant sand. Students first exam the crime scene and collect evidence using standard forensic techniques. The students are then provided with a narrative concerning the whereabouts of the victim in the past 24 hours and samples of sand from locations where the victim was sighted. The students do a size analysis of the sand associated with the victim and the various possible crime scene locations. They microscopically examine the various sand samples and chara...

Since the inception of the term A-type by Loiselle and Wones (1979), this class of granitoids has... more Since the inception of the term A-type by Loiselle and Wones (1979), this class of granitoids has proven to be the most controversial and least understood member of the granitoid alphabet soup. Eby (1990, 1992) suggested that there were a variety of granitoids that fell within the A-type classification and that there were multiple petrogenetic pathways that could lead to rocks that met the largely chemical definition of A-type granitoids. The A1-type (often referred to as anorogenic) was a distinct group that had characteristics of magma derived from an OIB source and was inferred to be the fractionation product of an OIB-like basalt magma. The A2-type (often referred to as post-collisional or post-orogenic) represented all A-type granitoids not derived by fractionation of an OIB-like magma. These granitoids were generally emplaced shortly after an orogenic period and may have originated by melting of mantle material with crustal interaction or solely by the melting of crustal mater...