Strontium Isotope Upper

Strontium isotopes: applications - UC Santa Cruz

Strontium’s stable isotopes Capo RC, Stewart BW, Chadwick OA (1998) Strontium isotopes as tracers of ecosystem processes: theory and methods. Geoderma 82: 197-225 87 Rb half life is (87Ga) so the 87 Sr that exists on Earth is what was there when the …

Strontium isotope systematics for plagioclase of the ...

Abstract. We present in situ laser ablation–multicollector–inductively coupled plasma–mass spectrometry Sr isotope data for plagioclase from a reference stratigraphic profile of the entire Layered Series and Upper Border Series of the Skaergaard intrusion (East Greenland). Plagioclase Sr isotope compositions and anorthite contents vary systematically from the margins of the intrusion ...

Larger foraminifera and strontium isotope stratigraphy of ...

Steuber T, Korbar T, Jelaska V, Gusic I (2005) Strontium isotope stratigraphy of Upper Cretaceous platform carbonates of the island of Brac (Adriatic Sea, Croatia): implications for global correlation of platform evolution and biostratigraphy. Cretac Res 26:741–756 CrossRef Google Scholar.

Evolution of the upper mantle of the Earth’s Moon ...

Evolution of the upper mantle of the Earth’s Moon: Neodymium and strontium isotopic constraints from high-Ti mare basalts GREGORY A. SNYDER,’ DER-CHUEN LEE,~ LAWRENCE A. TAYLOR,’ ALEX N. HALLIDAY,’ and ERIC A. JERDE’

Origins of invasive piscivores determined from the ...

Apr 04, 2012· We examined strontium isotope ratios (87Sr/86Sr) in fish otoliths to determine the origins of invasive piscivores in the Upper Colorado River Basin (UCRB, western USA). We examined 87Sr/86Sr from fishes in different reservoirs, as well as the temporal stability and interspecies variability of 87Sr/86Sr of fishes within reservoirs, determined if 87Sr/86Sr would be useful for “fingerprinting ...

Strontium-isotope stratigraphy of Upper Cretaceous rudist ...

Strontium-isotope stratigraphy (SIS) uses the changing Sr-isotopic composition of seawater (McArthur, 1994, Veizer et al., 1997) and provides an alternative tool to establish a chronology of first and last occurrences of benthic fossils, because it correlates these with well-defined biostratigraphical zonations of other marine fossils, irrespective of depositional environment and ...

RI0195. Deposition and Diagenesis in a Marine-to-Evaporite ...

RI0195. Deposition and Diagenesis in a Marine-to-Evaporite Sequence: Permian Upper Wolfcamp Formation and Lower Wichita Group, Palo Duro Basin, Texas Panhandle, by R. S. Fisher and H. H. Posey. 34 p., 22 figs., 3 tables, 1990. ISSN: 0082335X: Print. To purchase this publication as a downloadable PDF, please order RI0195D.

Strontium and stable isotope evidence of human mobility ...

13 days ago· Here, we present temporal variations in the Sr isotope composition of 14 human deciduous teeth and the N and C stable isotope ratios of four human remains from the Grotta Paglicci site (Apulia ...

Revised Middle–Upper Jurassic strontium isotope ...

Sep 05, 2017· The Middle–Upper Jurassic strontium isotope stratigraphy has a great potential because of significant variations in the seawater 87 Sr/ 86 Sr ratios, common occurrences of well-preserved belemnite rostra and oyster shells, and its potential applicability to dating of hydrocarbon source rocks.

Strontium isotope stratigraphy of the Comanchean Series in ...

We have used the results from 135 strontium isotope analyses from fossils and rocks collected from 43 sites to define the “middle” Cretaceous path of seawater 87 Sr/ 86 Sr during Comanchean time. The section represents an estimated duration of 19.3 m.y., from late Aptian through late Cenomanian.

Strontium isotope disequilibrium of ... - SpringerLink

Jun 21, 2013· Abstract. We report in situ Sr isotope data for plagioclase of the Bushveld Complex. We found disequilibrium Sr isotopic compositions on several scales, (1) between cores and rims of plagioclase grains in the Merensky pyroxenite, the Bastard anorthosite, and the UG1 unit and its noritic footwall, (2) between cores of different plagioclase grains within thin sections of anorthosite and ...

Isotopes of strontium - Wikipedia

Because strontium has an electron configuration similar to that of calcium, it readily substitutes for Ca in minerals. In addition to the four stable isotopes, thirty-one unstable isotopes of strontium are known to exist (see Table, below): the longest-lived of these are 90 Sr with a half-life of 28.9 years and 85 Sr

Strontium isotope tracing in animal teeth at the ...

mobility of ancient animal and human populations. Strontium isotopes in fossil tooth enamel are compared to a geological, bio-available strontium isotope map, to determine whether teeth are from local or migrant individuals. This study was carried out on the Upper Pleistocene site of Les Pradelles (Marillac-le-Franc, Charente,

Strontium isotopic variations in Jurassic and Cretaceous ...

A high-resolution seawater strontium isotope curve has been generated through the analysis of well-dated and well-preserved belemnites and oysters from the Middle and Upper Jurassic and the Lower Cretaceous of Great Britain. Analysis of Fe and Mn concentrations in these fossils has yielded criteria for eliminating samples that are ...

Dolomitization by hypersaline reflux into dense ...

Strontium isotopes. Strontium isotope (87 Sr/ 86 Sr) analyses of TMD (Table 2) in the current study show a wide range of values (0·7080 to 0·7117), far higher than the marine 87 Sr/ 86 Sr ratio of 0·70775 measured by Korte et al. on brachiopods of the Muschelkalk Sea. Hauptmuschelkalk dolomites show values around 0·710, except for one ...

Variations in the strontium isotope composition of ...

Strontium isotope variations closely parallel sea level and benthic δ 18 O changes during the late Paleocene and early Eocene, supporting previous studies linking tectonic reorganization and increased volcanism to high sea level, high CO 2, and warm global temperatures.

The lead and strontium isotope geochemistry of ...

The lead and strontium isotope geochemistry of metalliferous sediments associated with Upper Cretaceous ophiolitic rocks in Cyprus, Syria, and the Sultanate of Oman N. H. Gale, , E. T. C. Spooner, and , P. J. Potts ...

USING STRONTIUM ISOTOPES IN CONJUNCTION WITH …

USING STRONTIUM ISOTOPES IN CONJUNCTION WITH MAJOR, AND TRACE ELEMENTS TO IDENTIFY WATER/ROCK INTERACTION IN THE UPPER KITTITAS COUNTY, WASHINGTON by James D. Patterson August 2017 The complex bedrock lithologies in the Upper Kittitas County provide an ideal setting for developing isotopic methodology to identify groundwater sources and track

The evolution of strontium isotopes in the upper ...

Apr 26, 1990· We argue here that the strontium isotope paradox instead largely reflects the gradual increase in Rb/Sr with time in the upper continental crust. ... The evolution of strontium isotopes …

Strontium isotope evidence for late Pleistocene ...

Here we resolve the timing of Lake Victoria's overflow by using strontium isotopes as a tracer for water from the principal lakes and rivers of the Upper Nile. Our data demonstrate that overflow of Lakes Victoria and Albert into the Nile drainage network occurred no later than 11.5 14 C ka.

STRONTIUM ISOTOPE DATING OF SPICULITIC PERMIAN …

Jun 23, 2010· Eight samples of brachiopod shell material have been analyzed for their strontium isotope composition in order to more accurately date Lower to Upper Permian siliceous biogenic strata of Spitsbergen (Kapp Starostin Formation) and the southern Barents Sea (Røye Formation).

SEAWATER STRONTIUM ISOTOPES, OCEANIC ANOXIC …

the end of the strontium-isotope excursion, whereas the two Cretaceous OAEs oc-curred at the onset of the accompanying strontium-isotope excursions. The possible causes of these excursions were evaluated by successively examining the changes in the riverine strontium fluxes, riverine 87Sr/86Sr ratios, or hydrothermal