Earth Sciences Commons^™

Assessment And Behaviour Of Secondary Iron(Iii) Minerals In Acid Sulphate Soil Materials, Chamindra Vithana

Chamindra Vithana

This study examined two aspects of acidity generating secondary Fe(III) minerals (i.e. schwertmannite and jarosite) in acid sulfate soils (ASS) environments: i) accurate identification and quantification, and ii) improving our understanding of their behaviour in ASS.The study showed that current assessment methods have a number of limitations and are not reliable for accurate estimation of both minerals in ASS environments. The study also showed that in natural environments, these minerals can behave in a manner different to current conceptual understanding. The broad implication of this study was identification of the need for development of improved management techniques for ASS.

Controls On Trace Metal Authigenic Enrichment In Reducing Sediments: Insights From Modern Oxygen-Deficient Settings, Susan Little, Derek Vance, Timothy Lyons, James Mcmanus

James McManus

Any effort to reconstruct Earth history using variations in authigenic enrichments of redox-sensitive and biogeochemically important trace metals must rest on a fundamental understanding of their modern oceanic and sedimentary geochemistry. Further, unravelling the multiple controls on sedimentary enrichments requires a multi-element approach. Of the range of metals studied, most is known about the behavior of Fe, Mn, and Mo. In this study, we compare the authigenic enrichment patterns of these elements with a group whose behavior is not as well defined (Cd, Cu, Zn, and Ni) in three oxygen-poor settings: the Black Sea, the Cariaco Basin (Venezuela), and the …

Microbial Utilization Of Abiogenic Carbon And Hydrogen In A Serpentinite-Hosted System, Susan Lang, G. Früh-Green, S. Bernasconi, M. Lilley, G. Proskurowski, S. Méhay, D. Butterfield

Susan Q. Lang

No abstract provided.

Serpentinization, Carbon, And Deep Life, M. Schrenk, W. Brazelton, Susan Lang

Susan Q. Lang

No abstract provided.

Elevated Concentrations Of Formate, Acetate And Dissolved Organic Carbon Found At The Lost City Hydrothermal Field, Susan Lang, D. Butterfield, M. Schulte, D. Kelley, M. Lilley

Susan Q. Lang

No abstract provided.

Stable Isotope Analysis Of Organic Carbon In Small (Μg C) Samples And Dissolved Organic Matter Using A Gasbench Preparation Device, Susan Lang, S. Bernasconi, G. Früh-Green

Susan Q. Lang

No abstract provided.

Sources And Cycling Of Carbon In Continental, Serpentinite-Hosted Alkaline Springs In The Voltri Massif, Italy, E. Schwarzenbach, Susan Lang, G. Früh-Green, M. Lilley, S. Bernasconi, S. Méhay

Susan Q. Lang

No abstract provided.

Purification Of Fire Derived Markers For Μg Scale Isotope Analysis (Δ13c, Δ14c) Using High Performance Liquid Chromatography (Hplc), M. Gierga, M. Schneider, D. Wiedemeier, Susan Lang, R. Smittenberg, I. Hajdas, S. Bernasconi, M. Schmidt

Susan Q. Lang

No abstract provided.

Dissolved Organic Carbon In Ridge-Axis And Ridge-Flank Hydrothermal Systems, Susan Lang, D. Butterfield, M. Lilley, H. Johnson, J. Hedges

Susan Q. Lang

No abstract provided.

Determination Of The Cec In Srs Soils And The Capability Of Epa Model 9081 For Cec Of Acidic Soils, Alexandra Simpson

Alexandra M Simpson

No abstract provided.

Determination Of The Cec In Srs Soils And The Capability Of Epa Model 9081 For Cec Of Acidic Soils, Alexandra Simpson

Alexandra M Simpson

No abstract provided.

Arsenic Mobilization And Iron Transformations During Sulfidization Of As(V)-Bearing Jarosite, Scott Johnston, Edward Burton, Annabelle Keene, Britta Planer-Friedrich, Andreas Voegelin, Mark Blackford, Greg Lumpkin

Associate Professor Edward D Burton

Jarosite (KFe3(SO4) 2(OH)6) is an important host-phase for As in acid mine drainage (AMD) environments and coastal acid sulfate soils (CASS). In AMD and CASS wetlands, jarosite may encounter S(−II) produced by sulfate reducing bacteria. Here, we examine abiotic sulfidization of As(V)-bearing K-jarosite at pH 4.0, 5.0, 6.5 and 8.0. We quantify the mobilization and speciation of As and identify corresponding Fe mineral transformations. Sulfide-promoted dissolution of jarosite caused release of co-precipitated As and the majority of mobilized As was re-partitioned to a readily exchangeable surface complex (AsEx). In general, maximum As mobilization occurred in the highly sulfidized end-members of …

Plio-Quaternary Exhumation History Of The Central Nepalese Himalaya: 2. Thermo-Kinematic Model Of Thermochronometer Age Prediction Model, David Whipp Jr, Todd Ehlers, Ann Blythe, Katharine Huntington, Kip Hodges, Douglas Burbank

Ann Blythe

[1] In the Himalaya and other active convergent orogens, linear relationships between thermochronometer sample age and elevation are often used to estimate long-term exhumation rates. In these regions, high-relief topography and nonvertical exhumation pathways may invalidate such one-dimensional (1-D) interpretations and lead to significant errors. To quantify these errors, we integrate apatite fission track (AFT) ages from the central Himalaya with a 3-D coupled thermokinematic model, from which sample cooling ages are predicted using a cooling-rate-dependent algorithm. By changing the slip partitioning between faults near the Main Central thrust and the Main Frontal thrust system at the Himalayan range front, …

The Diachroneity Of Alluvial-Fan Lithostratigraphy?: A Test Case From Southeastern Ebro Basin Magnetostratigraphy, Nicholas Swanson-Hysell, David Barbeau

David L Barbeau Jr

Alluvial-fan strata contain valuable proxy data for kinematic, climatic and sediment-flux phenomena associated with high-relief source regions. Proper application of this data is dependent upon acquisition of accurate high-resolution chronostratigraphic data, best achieved through magnetostratigraphy. Collection of magnetostratigraphic and other proxy data from composite alluvial-fan sections assumes the chronostratigraphic significance of lithostratigraphy. We present the first test of this assumption with new magnetostratigraphy collected from Paleogene rocks of the southeastern Ebro basin. We report five new magnetostratigraphic sections that collectively sample 850 m of alluvial-fan and associated fluvial strata. One-hundred meters of lithostratigraphic overlap between these sections reveals equivalent magnetic …

Knowledge Discovery From Multispectral Satellite Images, Arun D. Kulkarni

Arun Kulkarni