Results 91 to 100 of about 21,047 (239)

A new method for amino acid geochronology of the shell of the bivalve mollusc Arctica islandica [PDF]

Geochronology
The bivalve mollusc Arctica islandica can live for hundreds of years, and its shell has provided a valuable resource for sclerochronological studies and geochemical analyses for understanding palaeoenvironmental change. Shell specimens recovered from the
M. L. G. Conti, P. G. Butler, D. J. Reynolds, T. Trofimova, J. D. Scourse, K. E. H. Penkman   +5 more
doaj   +1 more source

Origin of carbonate-silicate rocks of the Porya Guba (the Lapland-Kolvitsa Granulite Belt) revealed by stable isotope analysis (δ18O, δ13C)

Записки Горного института
Carbonate-silicate rocks of unclear origin have been observed in granulites of the Porya Guba of the Lapland-Kolvitsa Belt within the Fennoscandinavian Shield.
Dmitrii P. Krylov, Ekaterina V. Klimova
doaj  

Geochemical characterization of Gubanovskaya intrusion of rapakivi granites (Wiborg massif)

Vestnik MGTU
The paper presents new data on geology and composition of rapakivi granites of Gubanovskaya intrusion (Wiborg massif). Petrographic and geochemical characteristics of rapakivi granites of the second (ovoid) and third (trachytoid) phases of intrusion, as ...
Rogova I. V., Skublov S. G., Berezin A. V., Petrov D. A.   +3 more
doaj   +1 more source

An optimization tool for identifying multiple-diffusion domain model parameters [PDF]

Geochronology
The multiple-diffusion domain (MDD) model empirically describes the diffusive behavior of noble gases in some terrestrial materials and has been commonly used to interpret 40Ar/39Ar stepwise degassing observations in K-feldspar.
A. L. Gorin, A. L. Gorin, J. M. Gorin, M. Bergelin, D. L. Shuster, D. L. Shuster   +5 more
doaj  

Short communication: Nanoscale heterogeneity of U and Pb in baddeleyite from atom probe tomography – ²³⁸U series alpha recoil effects and U atom clustering [PDF]

Geochronology
Atom probe tomography (APT) of 238U and 206Pb has been applied to baddeleyite crystals from the Hart Dolerite (1791±1 Ma) and the Great Dyke of Mauritania (2732±2 Ma) in an effort to constrain the average nuclear recoil distance of 238U series daughter ...
S. Denyszyn, D. W. Davis, D. Fougerouse
doaj   +1 more source

Trace element composition of silicate minerals from Kunashak Meteorite (L6)

Записки Горного института
Major (EPMA) and trace (SIMS) element geochemistry in the silicate minerals (olivine, pyroxene and plagioclase) of Kunashak equilibrated ordinary chondrite (L6) is described. No variations in the major element concentrations of the silicate minerals have
Kristina G. Sukhanova, Olga L. Galankina
doaj  

Nonparametric estimation of age–depth models from sedimentological and stratigraphic information [PDF]

Geochronology
Age–depth models are fundamental tools used in all geohistorical disciplines. They assign stratigraphic positions to ages (e.g., in drill cores or outcrops), which is necessary to estimate rates of past environmental change and establish timing of events
N. Hohmann, D. De Vleeschouwer, S. Batenburg, S. Batenburg, E. Jarochowska   +4 more
doaj   +1 more source

Early Cretaceous trachytes and basement rocks from northeastern Mongolia: a Sr-Nd-Pb isotope study

Frontiers in Earth Science, 2023
Maksim V. Kuznetsov, Valery M. Savatenkov, Valery M. Savatenkov, Thomas C. Sheldrick, Lidiya V. Shpakovich   +4 more
doaj   +1 more source

Lithostratigraphy of the Lower Cretaceous of Southwestern and Central Crimea

Russian Journal of Earth Sciences
The revision and updating of the local geological units of the Lower Cretaceous in the Southwestern and Central Crimea have been carried out. For this purpose, the materials presented in numerous publications and the results obtained by the authors ...
Dubkova K. A., Shishlov S. B., Kolbanova A. V.   +2 more
doaj   +1 more source

Zircon Internal Deformation and Its Effect on U-Pb Geochronology: A Case Study from the Himalayan High-Pressure Eclogites

Zircon, with a chemical formula of ZrSiO4, is a widely used mineral for determining the crystallization age of igneous rocks. It is also used to constrain the timing of metamorphic events from its overgrowth or recrystallized domains.
Hafiz U. Rehman
core   +1 more source