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Article: Groundwater mixing in an alkaline paleolake: Eocene Green River Formation, Wyoming

Baddouh, M'bark / Carroll, Alan R / Jagniecki, Elliot A / Beard, Brian L / Lowenstein, Tim K / Johnson, Clark M

Palaeogeography, palaeoclimatology, palaeoecology. 2021 Jan. 01, v. 561

2021

Abstract: Tufa in the Little Mesa area of the northern Bridger Basin has been interpreted to record carbonate deposition via subaqueous and subaerial springs emanating near the shoreline of Eocene Lake Gosiute. Sedimentary facies record an overall transgression, ... ...

Abstract	Tufa in the Little Mesa area of the northern Bridger Basin has been interpreted to record carbonate deposition via subaqueous and subaerial springs emanating near the shoreline of Eocene Lake Gosiute. Sedimentary facies record an overall transgression, culminating with mound structures that reach up to 9 m in height and 40 m in diameter. Mounds exhibit a strong positive, linear covariance between δ¹³C and δ¹⁸O, defining a slope of ~1. Similar trends occur in many other paleolake deposits, where they are interpreted to reflect changes in evaporation, atmospheric CO₂ exchange, and organic matter burial. However, δ¹³C and δ¹⁸O in this study also covary strongly with ⁸⁷Sr/⁸⁶Sr, a new finding that is inconsistent with previously proposed mechanisms. We conclude that Little Mesa isotopic trends reflect mixing of groundwater with low ⁸⁷Sr/⁸⁶Sr, δ¹⁸O and δ¹³C and lake water with opposite characteristics. Low ⁸⁷Sr/⁸⁶Sr in groundwater likely resulted from interaction with marine carbonate strata within the Sevier fold and thrust belt to the west, whereas drainage from Precambrian-cored uplifts that bounded Lake Gosiute to the north, east, and south was responsible for higher lake water ratios.Little Mesa carbonate facies are all less radiogenic than any time-equivalent facies near the center of the basin, implying horizontal and vertical gradients in Lake Gosiute ⁸⁷Sr/⁸⁶Sr. Previous studies have shown that the lowest ⁸⁷Sr/⁸⁶Sr in basin center deposits correspond to lake highstands. Results of this study support the hypothesis that climatic modulation of surface runoff and spring emanations from the Sevier belt were principally responsible for precessional-scale expansions and contractions of Lake Gosiute. More broadly, groundwater discharge may represent an important but underappreciated contributor to covariance between ⁸⁷Sr/⁸⁶Sr ratios, δ¹³C and δ¹⁸O in closed paleolake systems.
Keywords	Eocene epoch ; basins ; carbon dioxide ; carbonates ; covariance ; drainage ; evaporation ; groundwater ; lakes ; organic matter ; palaeogeography ; paleoclimatology ; paleoecology ; runoff ; shorelines ; spring ; Green River ; Wyoming
Language	English
Dates of publication	2021-0101
Publishing place	Elsevier B.V.
Document type	Article
Note	NAL-AP-2-clean
ZDB-ID	417718-6
ISSN	0031-0182
ISSN	0031-0182
DOI	10.1016/j.palaeo.2020.110038
Database	NAL-Catalogue (AGRICOLA)

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Article: Early Archean biogeochemical iron cycling and nutrient availability: New insights from a 3.5 Ga land-sea transition

Johnson, Clark M. / Zheng, Xin-Yuan / Djokic, Tara / Van Kranendonk, Martin J. / Czaja, Andrew D. / Roden, Eric E. / Beard, Brian L.

Earth-science reviews. 2022 Mar. 10,

2022

Abstract: The chemical and isotopic compositions of Precambrian Fe-rich chemical sedimentary rocks have figured prominently in discussions on the Fe biogeochemical cycle and redox conditions in the early Earth. Broad trends of decreasing δ⁵⁶Fe values for Eoarchean ...

Abstract	The chemical and isotopic compositions of Precambrian Fe-rich chemical sedimentary rocks have figured prominently in discussions on the Fe biogeochemical cycle and redox conditions in the early Earth. Broad trends of decreasing δ⁵⁶Fe values for Eoarchean to Paleoproterozoic iron formations (IFs) and jaspilites (hematite-chert) with decreasing age reflect a general increase in extent of oxidation of aqueous Fe(II) (Fe(II)ₐq) in marine environments, consistent with increasing oxygenation of surface environments, particularly since the Mesoarchean. Such trends may record a shift from anaerobic to aerobic oxidation, in part reflecting increasing nutrient abundances that follow increased emergence of continental crust. It is commonly proposed that the size of the biosphere in the early Archean was largely nutrient limited, specifically P limited. Highly positive δ⁵⁶Fe values for Fe oxides in chemical sedimentary rocks deposited in open marine environments at this time are consistent with excess Fe(II)ₐq. Here, we present new data on Fe isotopes and trace element chemistry for 3.4–3.5 Ga jaspilites from the North Pole region of the Pilbara Craton, including the first example of a land-sea transition preserved in the lower Dresser Formation as jaspilite deposition in restricted basin and open-marine settings. A review of the possible mechanisms of Fe(II)ₐq oxidation in the early Archean - including O₂ generated by oxygenic photosynthesis, UV photo-oxidation, or photoferrotrophy (anoxygenic photosynthesis) - suggests that the latter is most likely, in light of evidence for low-O₂ contents and the strong role that silica plays in inhibiting abiologic Fe(II) oxidation. Y + REE contents of lower Dresser Formation jaspilites indicate a freshwater component in the restricted basin settings, in contrast to exclusively seawater components in the open-marine environments. δ⁵⁶Fe values for open-marine jaspilites are highly positive. (δ⁵⁶Fe ~ +1 to +2.4‰), similar to other jaspilites and IFs of Eoarchean to Paleoarchean age. Assuming photoferrotrophy as the oxidative pathway, this would indicate electron donor (Fe(II)ₐq) excess and nutrient limitation. For the restricted-basin jaspilites of the lower Dresser Formation, δ⁵⁶Fe values extend to slightly negative values (δ⁵⁶Fe ~ −0.4‰), correlating with changes in Y + REE contents that indicate fluid mixing. In toto, there is a range of ~3‰ in δ⁵⁶Fe values across the land-sea transition of the lower Dresser Formation, significantly exceeding the range previously measured in early Archean jaspilites. Combined with an advection-dispersion-reaction model for Fe(II)ₐq oxidation via photoferrotrophy, these observations suggest a range of nutrient abundance with environment, where samples from near-shore or restricted settings record excess nutrients from terrestrial input and hence electron donor limitation. Integrating the new results from the Pilbara Craton with the broader Fe isotope database for Eoarchean through Paleoarchean jaspilites and IFs, as well as a simple mass-balance model relating δ⁵⁶Fe values and P contents, it becomes apparent that the relatively high nutrient abundance seen only in restricted settings at ~3.5 Ga becomes more characteristic of the open oceans by ~3.2 Ga. This expansion of nutrient availability is correlated with a marked increase in ⁸⁷Sr/⁸⁶Sr ratios for seawater, which can be shown to be a proxy for P delivery to the open oceans from the continents via weathering fluxes. Collectively, these findings demonstrate the importance of considering geologic context in interpreting Fe isotope and chemical compositions of jaspilites and IFs. Capture of the land-sea transition of the lower Dresser Formation provides insights into the biosphere that would have been missed in sample suites that only record open-marine conditions.
Keywords	Eoarchean era ; Mesoarchean era ; Paleoarchean era ; Paleoproterozoic era ; basins ; biogeochemical cycles ; biosphere ; databases ; freshwater ; models ; nutrient availability ; photooxidation ; photosynthesis ; seawater ; silica ; Arctic region
Language	English
Dates of publication	2022-0310
Publishing place	Elsevier B.V.
Document type	Article
Note	Pre-press version
ZDB-ID	1792-9
ISSN	0012-8252
ISSN	0012-8252
DOI	10.1016/j.earscirev.2022.103992
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Constraining silicon isotope exchange kinetics and fractionation between aqueous and amorphous Si at room temperature

Zheng, Xin-Yuan / Beard, Brian L. / Johnson, Clark M.

2019

Abstract: Silicon (Si) isotopes are useful tracers for the modern and ancient Si cycle, but their interpretation is limited by inadequate understanding of Si isotope exchange kinetics and fractionation factors at low temperature. This study investigated Si isotope ...

Abstract	Silicon (Si) isotopes are useful tracers for the modern and ancient Si cycle, but their interpretation is limited by inadequate understanding of Si isotope exchange kinetics and fractionation factors at low temperature. This study investigated Si isotope exchange and fractionation between aqueous and amorphous Si at circumneutral pH and room temperature through a series of 29Si-spiked isotope-exchange experiments. Four different amorphous Si solids with varied surface areas were reacted with aqueous Si solutions of high ionic strength similar to seawater, or low ionic strength typical of freshwater, under conditions close to chemical equilibrium with respect to amorphous Si solubility. In contrast to the common perception of negligible Si isotope exchange at low temperature, ∼50–85% isotope exchange was achieved between aqueous and amorphous Si within ∼60 days. Larger solid surface areas and higher aqueous ionic strength generally promoted Si isotope exchange. Drying/aging of Si gel, however, impedes Si isotope exchange between amorphous and aqueous Si relative to freshly prepared Si gels. Excluding the experiments that used the aged Si gel, temporal trajectories of Si isotope evolution of the two phases from all other experiments showed significant curvature in three-isotope space (29Si/28Si and 30Si/28Si). These results can be best explained by a model that comprises two Si isotope exchange processes with different exchange rates and fractionation factors during the interactions between aqueous and amorphous Si towards isotope equilibrium. The faster exchange is associated with surface sites, and slower exchange occurs between exterior and interior Si atoms of the solid. Exchange with surface sites tends to partition heavy Si isotopes in the aqueous phase relative to the solid surface, whereas exchange between surface and interior sites in the solid tends to enrich heavy Si isotopes in the interior. Two experiments that achieved >80% isotope exchange provided the best estimates of equilibrium Si isotope ...
Subject code	541
Language	English
Publisher	Elsevier
Publishing country	de
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Stable potassium (K) isotope characteristics at mid-ocean ridge hydrothermal vents and its implications for the global K cycle

Zheng, Xin-Yuan / Beard, Brian L. / Neuman, Mason / Fahnestock, Maria F. / Bryce, Julia G. / Johnson, Clark M.

2022

Abstract: Highlights • Potassium isotopes of modern hydrothermal fluids are reported for the first time. • Potassium isotope fractionation in hydrothermal systems is resolved and quantified. • Hydrothermal systems cannot explain the heavy K isotope signature of ... ...

Abstract	Highlights • Potassium isotopes of modern hydrothermal fluids are reported for the first time. • Potassium isotope fractionation in hydrothermal systems is resolved and quantified. • Hydrothermal systems cannot explain the heavy K isotope signature of seawater. • Authigenic clay formation likely has a significant role in the global K cycle. Recent discoveries of significant variations in stable K isotope ratios (41K/39K or K) among various terrestrial samples indicate that K isotopes can be a novel tracer for the global K cycle, but a key observation that seawater K is ‰ higher than the bulk silicate Earth remains unexplained. An unconstrained component critical to this puzzle is hydrothermal systems that represent both a major K source and sink in the ocean. Here we report K results on mid-ocean ridge (MOR) hydrothermal fluids from the Gorda Ridge and ∼9°N East Pacific Rise (EPR), including time-series samples that recorded major perturbations in fluid chemistry induced by a local volcanic eruption. Fluid K values range from -0.46‰ to -0.15‰, falling between those of fresh basalts and seawater. K values of “time-zero” fluids collected shortly after the volcanic eruption are shifted towards the seawater value, followed by a return to pre-eruption values within ∼2 years. Fluid K variations are largely influenced by water–rock interactions, but they cannot be solely explained by simple mixing of seawater and K leached from basalts at high temperatures. Instead, these data imply small but significant isotope fractionation that enriches heavy K isotopes in basalts, likely caused by low-temperature alteration during the recharge stage of hydrothermal circulation. Our results preclude MOR hydrothermal systems as the cause for the heavy K value of seawater. Using fluid K data and K isotope fractionation constrained here for hydrothermal systems, a K mass-balance model implies a critical role for a marine sedimentary sink, possibly authigenic clay formation, in the global K cycle. Also, applying the K isotope ...
Subject code	550
Language	English
Publisher	Elsevier
Publishing country	de
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Biologically recycled continental iron is a major component in banded iron formations.

Li, Weiqiang / Beard, Brian L / Johnson, Clark M

Proceedings of the National Academy of Sciences of the United States of America

2015 Volume 112, Issue 27, Page(s) 8193–8198

Abstract: Banded iron formations (BIFs) record a time of extensive Fe deposition in the Precambrian oceans, but the sources and pathways for metals in BIFs remain controversial. Here, we present Fe- and Nd-isotope data that indicate two sources of Fe for the large ...

Abstract	Banded iron formations (BIFs) record a time of extensive Fe deposition in the Precambrian oceans, but the sources and pathways for metals in BIFs remain controversial. Here, we present Fe- and Nd-isotope data that indicate two sources of Fe for the large BIF units deposited 2.5 billion y ago. High-εNd and -δ(56)Fe signatures in some BIF samples record a hydrothermal component, but correlated decreases in εNd- and δ(56)Fe values reflect contributions from a continental component. The continental Fe source is best explained by Fe mobilization on the continental margin by microbial dissimilatory iron reduction (DIR) and confirms for the first time, to our knowledge, a microbially driven Fe shuttle for the largest BIFs on Earth. Detailed sampling at various scales shows that the proportions of hydrothermal and continental Fe sources were invariant over periods of 10(0)-10(3) y, indicating that there was no seasonal control, although Fe sources varied on longer timescales of 10(5)-10(6) y, suggesting a control by marine basin circulation. These results show that Fe sources and pathways for BIFs reflect the interplay between abiologic (hydrothermal) and biologic processes, where the latter reflects DIR that operated on a basin-wide scale in the Archean.
MeSH term(s)	Earth, Planet ; Ferric Compounds/metabolism ; Ferrous Compounds/metabolism ; Geologic Sediments/chemistry ; Geologic Sediments/microbiology ; Geological Phenomena ; Iron/metabolism ; Isotopes/metabolism ; Neodymium/metabolism ; Oceans and Seas ; Oxidation-Reduction ; Radiometric Dating ; Seawater/chemistry ; Seawater/microbiology ; Time Factors
Chemical Substances	Ferric Compounds ; Ferrous Compounds ; Isotopes ; Neodymium (2I87U3734A) ; Iron (E1UOL152H7)
Language	English
Publishing date	2015-06-24
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
ZDB-ID	209104-5
ISSN	1091-6490 ; 0027-8424
ISSN (online)	1091-6490
ISSN	0027-8424
DOI	10.1073/pnas.1505515112
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Article ; Online: Geochemical and Stable Fe Isotopic Analysis of Dissimilatory Microbial Iron Reduction in Chocolate Pots Hot Spring, Yellowstone National Park.

Fortney, Nathaniel W / Beard, Brian L / Hutchings, Jack A / Shields, Michael R / Bianchi, Thomas S / Boyd, Eric S / Johnson, Clark M / Roden, Eric E

Astrobiology

2020 Volume 21, Issue 1, Page(s) 83–102

Abstract: Chocolate Pots hot spring (CP) is an Fe-rich, circumneutral-pH geothermal spring in Yellowstone National Park. Relic hydrothermal systems have been identified on Mars, and modern hydrothermal environments such as CP are useful for gaining insight into ... ...

Abstract	Chocolate Pots hot spring (CP) is an Fe-rich, circumneutral-pH geothermal spring in Yellowstone National Park. Relic hydrothermal systems have been identified on Mars, and modern hydrothermal environments such as CP are useful for gaining insight into potential pathways for generation of biosignatures of ancient microbial life on Earth and Mars. Fe isotope fractionation is recognized as a signature of dissimilatory microbial iron oxide reduction (DIR) in both the rock record and modern sedimentary environments. Previous studies in CP have demonstrated the presence of DIR in vent pool deposits and show aqueous-/solid-phase Fe isotope variations along the hot spring flow path that may be linked to this process. In this study, we examined the geochemistry and stable Fe isotopic composition of spring water and sediment core samples collected from the vent pool and along the flow path, with the goal of evaluating whether Fe isotopes can serve as a signature of past or present DIR activity. Bulk sediment Fe redox speciation confirmed that DIR is active within the hot spring vent pool sediments (but not in more distal deposits), and the observed Fe isotope fractionation between Fe(II) and Fe(III) is consistent with previous studies of DIR-driven Fe isotope fractionation. However, modeling of sediment Fe isotope distributions indicates that DIR does not produce a unique Fe isotopic signature of DIR in the vent pool environment. Because of rapid chemical and isotopic communication between the vent pool fluid and sediment, sorption of Fe(II) to Fe(III) oxides would produce an isotopic signature similar to DIR despite DIR-driven generation of large quantities of isotopically light solid-associated Fe(II). The possibility exists, however, for preservation of specific DIR-derived Fe(II) minerals such as siderite (which is present in the vent pool deposits), whose isotopic composition could serve as a long-term signature of DIR in relic hot spring environments.
MeSH term(s)	Chocolate ; Ferric Compounds ; Geologic Sediments ; Hot Springs ; Iron/analysis ; Isotopes ; Oxidation-Reduction ; Parks, Recreational
Chemical Substances	Ferric Compounds ; Isotopes ; Iron (E1UOL152H7)
Language	English
Publishing date	2020-06-22
Publishing country	United States
Document type	Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
ZDB-ID	2047736-3
ISSN	1557-8070 ; 1531-1074
ISSN (online)	1557-8070
ISSN	1531-1074
DOI	10.1089/ast.2019.2058
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Book ; Conference proceedings: Geochemistry of non-traditional stable isotopes

Johnson, Clark M

(Reviews in mineralogy and geochemistry ; 55)

2004

Institution	Mineralogical Society of America
Event/congress	Meeting (2004.05.15-16, Montreal)
Author's details	Mineralogical Society of America ... Ed.: Clark M. Johnson
Series title	Reviews in mineralogy and geochemistry ; 55
Keywords	Isotopengeochemie ; Stabiles Isotop
Language	English
Size	XV, 454 S, Ill., graph. Darst., Kt
Publisher	Mineralogical Society of America u.a.
Publishing place	Washington, DC
Document type	Book ; Conference proceedings
Note	Literaturangaben
ISBN	0939950677 ; 9780939950676
Database	Former special subject collection: coastal and deep sea fishing

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Book ; Conference proceedings: Geochemistry of non-traditional stable isotopes

Johnson, Clark M

(Reviews in mineralogy and geochemistry ; 55)

2004

Institution	Mineralogical Society of America
Event/congress	Meeting (2004.05.15-16, Montreal)
Author's details	Mineralogical Society of America ... Ed.: Clark M. Johnson
Series title	Reviews in mineralogy and geochemistry ; 55
Keywords	Isotopengeochemie ; Stabiles Isotop
Language	English
Size	XV, 454 S, Ill., graph. Darst., Kt
Publisher	Mineralogical Society of America u.a.
Publishing place	Washington, DC
Document type	Book ; Conference proceedings
Note	Literaturangaben
ISBN	0939950677 ; 9780939950676
Database	Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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Article: U–Th–Pb isotope data indicate phanerozoic age for oxidation of the 3.4Ga Apex Basalt

Li, Weiqiang / Johnson, Clark M / Beard, Brian L

Earth and planetary science letters. 2012 Feb. 15, v. 319-320

2012

Abstract: The occurrence of ferric oxides in Archean rocks has played an important role in discussions on the amount of free oxygen in the atmosphere of the ancient Earth. Recognizing that post-Archean weathering may also produce oxide minerals, drill cores have ... ...

Abstract	The occurrence of ferric oxides in Archean rocks has played an important role in discussions on the amount of free oxygen in the atmosphere of the ancient Earth. Recognizing that post-Archean weathering may also produce oxide minerals, drill cores have been used to obtain samples beneath the depth of Phanerozoic weathering. The first core of the Archean Biosphere Drilling Project (ABDP-1) documented hematite as alteration products in 3.4Ga basalts from the Marble Bar area of the Pilbara Craton, NW Australia, and this has been used to infer the presence of an O₂-bearing atmosphere in the Archean. It is possible, however, that despite recovery of samples from >100m depth, oxidation of the basalts occurred much younger than the depositional age. In this study, the age of oxidation of the Apex Basalt from the ABDP-1 drill core at Marble Bar is constrained by U–Th–Pb geochronology. Lead and U concentrations of the basalts from the ABDP-1 drill core vary greatly, between <1–58ppm and 0.08–1.04ppm, respectively, whereas Th contents are more restricted (0.24–0.71ppm). ²⁰⁶Pb/²⁰⁴Pb ratios are non-radiogenic and vary from 12.44 to 14.69. The linear array in terms of ²⁰⁶Pb/²⁰⁴Pb–²⁰⁷Pb/²⁰⁴Pb variations does not reflect an age but reflects two-component mixing between a non-radiogenic “ore lead” end member and a radiogenic “basalt lead” end member. The samples do not form isochrons on ²³⁸U/²⁰⁴Pb–²⁰⁶Pb/²⁰⁴Pb, ²³⁵U/²⁰⁴Pb–²⁰⁷Pb/²⁰⁴Pb, or ²³²Th/²⁰⁴Pb–²⁰⁸Pb/²⁰⁴Pb diagrams, indicating post-formation U and Pb addition. Comparison of measured U/Th ratios with “model” U/Th ratios calculated based on ²⁰⁸Pb/²⁰⁴Pb–²⁰⁶Pb/²⁰⁴Pb variations indicates that U enrichment most likely occurred in the last 200Ma. The degree of U enrichment in the samples is correlated with Fe⁽ᴵᴵᴵ⁾/FeTₒₜₐₗ ratios, indicating that U addition and oxidation were related, most likely reflecting penetration of oxygenated surface waters in the Phanerozoic along bedding planes and shear zones. These results, therefore, indicate that oxidation of the Apex Basalt did not occur in the Archean, and therefore cannot be used to infer an oxygenated atmosphere at that time.
Keywords	basalt ; biosphere ; drilling ; hematite ; isotopes ; lead ; mixing ; models ; oxidation ; oxides ; oxygen ; surface water ; weathering ; Australia
Language	English
Dates of publication	2012-0215
Size	p. 197-206.
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	1466659-5
ISSN	1385-013X ; 0012-821X
ISSN (online)	1385-013X
ISSN	0012-821X
DOI	10.1016/j.epsl.2011.12.035
Database	NAL-Catalogue (AGRICOLA)

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Article: Exchange and fractionation of Mg isotopes between epsomite and saturated MgSO₄ solution

Li, Weiqiang / Beard, Brian L / Johnson, Clark M

Geochimica et cosmochimica acta. 2011 Apr. 1, v. 75, no. 7

2011

Abstract: The equilibrium Mg isotope fractionation factor between epsomite and aqueous MgSO₄ solution has been measured using the three isotope method in recrystallization experiments conducted at 7, 20, and 40°C. Complete or near-complete isotopic exchange was ... ...

Abstract	The equilibrium Mg isotope fractionation factor between epsomite and aqueous MgSO₄ solution has been measured using the three isotope method in recrystallization experiments conducted at 7, 20, and 40°C. Complete or near-complete isotopic exchange was achieved within 14days in all experiments. The Mg isotope exchange rate between epsomite and MgSO₄ solution is dependent on the temperature, epsomite seed crystal grain size, and experimental agitation method. The Mg isotope fractionation factors (Δ²⁶Mgₑₚₛ–ₛₒₗ) at 7, 20, and 40°C are 0.63±0.07‰, 0.58±0.16‰, and 0.56±0.03‰, respectively. These values are indistinguishable within error, indicating that the Mg isotope composition of epsomite is relatively insensitive to temperature. The magnitude of the isotope fractionation factor (Δ²⁶Mgₑₚₛ–ₛₒₗ=ca. 0.6‰ between 7 and 40°C) indicates that significant Mg isotope variations can be produced in evaporite sequences, and Mg isotopes may therefore, constrain the degree of closed-system behavior, paleo-humidity, and hydrological history of evaporative environments.
Keywords	agitation ; epsomite ; hydrology ; isotope fractionation ; isotopes ; magnesium ; magnesium sulfate ; temperature
Language	English
Dates of publication	2011-0401
Size	p. 1814-1828.
Publishing place	Elsevier Ltd
Document type	Article
ZDB-ID	300305-x
ISSN	0016-7037
ISSN	0016-7037
DOI	10.1016/j.gca.2011.01.023
Database	NAL-Catalogue (AGRICOLA)

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