This integrative approach helps to place these events in a more robust temporal framework. When coupled with chemo- (⁸⁷Sr/⁸⁶Sr and ¹⁸⁷Os/¹⁸⁸Os isotopes) and bio-stratigraphy (ammonite and coccolith), our ReOs ages correlate with regional and global stratigraphic tie points corresponding to pivotal points of Early Jurassic time, such as the Sinemurian–Pliensbachian boundary event, T-OAE, and late Toarcian, that are otherwise weakly constrained by isotopic methods. Our ReOs age results bracket sediment deposition between the late Sinemurian-early Pliensbachian (192.11 ± 0.77 Ma and 193.83 ± 1.34 Ma ) and late Toarcian (180.10 ± 2.68 Ma ). Here, we report the first high-precision ReOs ages of organic-rich shale packages of the Gordondale and basal Poker Chip Members of the Lower Jurassic Fernie Formation of Northwestern Alberta, Canada from the Western Canadian Sedimentary Basin (WCSB). The cause of imprecision in ReOs ORS age dates, at least for the Toarcian, has been linked to subtle chemostratigraphic variations in ¹⁸⁷Os/¹⁸⁸Osi values. Despite this, most studies to date have failed to obtain high precision, geologically meaningful, ages for such Lower Jurassic rocks. The Lower Jurassic rock record contains abundant organic-rich mudrocks suitable for refining Early Jurassic time using ReOs organic-rich shale (ORS) geochronometry, such as those associated with the Sinemurian–Pliensbachian boundary event or the Toarcian Ocean Anoxic Event (T-OAE). 160 Ma ago) was very unradiogenic (187Os/188Os 0.26) at the same time that the seawater Sr-isotope curve recorded its lowest value for the Phanerozoic, indicating that global continental weathering rates were very low at c. New results show that the Os-isotope composition of Callovian seawater (c. The present contribution reviews some recent developments in the application of the Re–Os isotope system to geochronological and palaeoenvironmental problems in the Mesozoic and earlier. The seawater Os-isotope record has yielded valuable information about several major episodes of past environmental change, and is particularly powerful when used in conjunction with other marine isotopic tracers such as carbon and strontium. Additionally, Re–Os analyses of ancient mudrocks have provided the best means so far of determining temporal changes in the Os-isotope composition of pre-Cenozoic seawater. Re and Os are also concentrated from seawater in organic-rich sediments and have been used to obtain absolute ages for the deposition of marine mudrock successions directly. * There's that whole collection of files that you wanted to convert to Mp3, but you first wanted to normalize them and make them fade in and out nicely.The rhenium–osmium (Re–Os) isotope system occupies a unique position amongst commonly used radiogenic parent–daughter isotope pairs on account of its siderophilic geochemical characteristics. * Amadeus Pro fully supports multitrack WAVE files and allows you to render sound on up to 5 different loudspeakers simultaneously. * Each track can have its volume adjusted independently from the others. * Amadeus Pro is a fully featured multitrack editor. Here are some key features of "Amadeus Pro": To purchase/download applications via the App Store an Apple account is required. NOTE: The Amadeus Pro 2.0 app can only be purchased via the Mac App Store (the buy link redirects you to its App Store page).
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