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Full-Text Articles in Physical Sciences and Mathematics
The Modern Mississippi: Provenance Indicators And Human Impact, Brittney Gregory
The Modern Mississippi: Provenance Indicators And Human Impact, Brittney Gregory
Brittney Gregory
No abstract provided.
Geochemistry Of The Great Valley Group: An Integrated Provenance Record, Kathleen Surpless
Geochemistry Of The Great Valley Group: An Integrated Provenance Record, Kathleen Surpless
Kathleen D. Surpless
Sedimentary geochemistry of fine-grained strata of the Great Valley Group (GVG) in California documents a provenance signal that may better represent unstable, mafic minerals and volcanic clasts within sediment source regions than the provenance signal documented in the petrofacies and detrital zircon analysis of coarser sedimentary fractions. Geochemistry of the GVG provides an overall provenance framework within which to interpret sandstone petrofacies and detrital zircon age signatures. The geochemical signature for all Sacramento Valley samples records an overall continental arc source, with significant variation but no clear spatial or temporal trends, indicating that the geochemical provenance signal remained relatively consistent …
Lithofacies Control In Detrital Zircon Provenance Studies: Insights From The Cretaceous Methow Basin, Southern Canadian Cordillera, Kathleen Surpless, J. Mahoney, Joseph Wooden, Michael Mcwilliams
Lithofacies Control In Detrital Zircon Provenance Studies: Insights From The Cretaceous Methow Basin, Southern Canadian Cordillera, Kathleen Surpless, J. Mahoney, Joseph Wooden, Michael Mcwilliams
Kathleen D. Surpless
High-frequency sampling for detrital zircon analysis can provide a detailed record of fine-scale basin evolution by revealing the temporal and spatial variability of detrital zircon ages within clastic sedimentary successions. This investigation employed detailed sampling of two sedimentary successions in the Methow/Methow-Tyaughton basin of the southern Canadian Cordillera to characterize the heterogeneity of detrital zircon signatures within single lithofacies and assess the applicability of detrital zircon analysis in distinguishing fine-scale provenance changes not apparent in lithologic analysis of the strata. The Methow/Methow-Tyaughton basin contains two distinct stratigraphic sequences of middle Albian to Santonian clastic sedimentary rocks: submarine-fan deposits of the …
Detrital Zircon Provenance Analysis Of The Great Valley Group, California: Evolution Of An Arc-Forearc System, Kathleen Surpless, Stephan Graham, Joseph Wooden, Michael Mcwilliams
Detrital Zircon Provenance Analysis Of The Great Valley Group, California: Evolution Of An Arc-Forearc System, Kathleen Surpless, Stephan Graham, Joseph Wooden, Michael Mcwilliams
Kathleen D. Surpless
The improved resolution of sediment provenance from detrital zircon analysis of Great Valley stratigraphy enables recognition of previously undocumented arc magmatism and the evolution of regional drainage systems within the Cretaceous arc-forearc system related to uplift, magmatism, and structure in the arc. Great Valley detrital zircon age data confirm previous studies that indicate that the locus of the sediment source in the southern Sierra Nevada arc migrated east with the active volcanic front and suggest rapid rates of uplift and unroofing of the southern arc. Sacramento Valley detrital zircon age data indicate a more complex history of drainage in the …
Provenance Of The Pythian Cave Conglomerate, Northern California: Implications For Mid-Cretaceous Paleogeography Of The U.S. Cordillera, Kathleen D. Surpless, Gregory Alan Augsburger
Provenance Of The Pythian Cave Conglomerate, Northern California: Implications For Mid-Cretaceous Paleogeography Of The U.S. Cordillera, Kathleen D. Surpless, Gregory Alan Augsburger
Kathleen D. Surpless
Provenance analysis of middle Cretaceous sedimentary rocks can help distinguish between disparate tectonic models of Cretaceous Cordilleran paleogeography by establishing links between sediment and source, as well as between currently separated basins. This study combines new detrital zircon age data and compositional data with existing provenance data for the Pythian Cave conglomerate, an informally-named unit deposited unconformably on the eastern Klamath Mountains, to test possible correlations between the Pythian Cave conglomerate and similar-age deposits in the Hornbrook Formation and the Great Valley Group. These provenance results indicate that restoring Late Cretaceous clockwise rotation of the Blue Mountains adds a significant …
Trace Element Chemistry Of Zircons From Oceanic Crust: A Method For Distinguishing Detrital Zircon Provenance, C B. Grimes, B E. John, P B. Kelemen, F K. Mazdab, J L. Wooden, M J. Cheadle, K Hanghoj, J J. Schwartz
Trace Element Chemistry Of Zircons From Oceanic Crust: A Method For Distinguishing Detrital Zircon Provenance, C B. Grimes, B E. John, P B. Kelemen, F K. Mazdab, J L. Wooden, M J. Cheadle, K Hanghoj, J J. Schwartz
Barbara John
We present newly acquired trace element compositions for more than 300 zircon grains in 36 gabbros formed at the slow-spreading Mid-Atlantic and Southwest Indian Ridges. Rare earth element patterns for zircon from modern oceanic crust completely overlap with those for zircon crystallized in continental granitoids. However, plots of U versus Yb and U/Yb versus Hf or Y discriminate zircons crystallized in oceanic crust from continental zircon, and provide a relatively robust method for distinguishing zircons from these environments. Approximately 80% of the modern ocean crust zircons are distinct from the fi eld defi ned by more than 1700 continental zircons …