Results 11 to 20 of about 1,847 (178)

Proterozoic and early Cambrian protists: evidence for accelerating evolutionary tempo. [PDF]

Proc Natl Acad Sci U S A, 1994
In rocks of late Paleoproterozoic and Mesoproterozoic age (ca. 1700-1000 million years ago), probable eukaryotic microfossils are widespread and well preserved, but assemblage and global diversities are low and turnover is slow.
Knoll AH.
europepmc   +3 more sources

MEZOPROTEROZOIC BASITE MAGMATISM OF THE BASHKIRIAN MEGANTICLINORIUM (SOUTHERN URALS): AGE CONSTRAINTS, PETROLOGICAL AND GEOCHEMICAL FEATURES

Геодинамика и тектонофизика, 2020
Among the Riphean–Vendian dyke complexes of the basic composition, which intersect the Precambrian strata of the Bashkirian meganticlinorium (Southern Urals), one of the most common is the Kurgas gabbro-dolerite complex dated to the Early – Middle ...
A. O. Khotylev, A. V. Tevelev, Ya. V. Bychkova, A. V. Latyshev, M. B. Anosova   +4 more
doaj   +1 more source

Chemostratigraphy of Neoproterozoic carbonates: implications for 'blind dating' [PDF]

, 2001
The delta C-13(carb) and Sr-87/Sr-86 secular variations in Neoproteozoic seawater have been used for the purpose of 'isotope stratigraphy' but there are a number of problems that can preclude its routine use.
Aharon P., Anthony E. Fallick, Anton B. Kuznetsov, Bowring S.A., Brand U., Brasier M.D., Brasier M.D., Brasier M.D., Burns S.J., Calver C.R., Corsetti F.A., Fairchild I.J., Fairchild I.J., Gao G., Gorokhov I.M., Gorokhov I.M., Gorokhov I.M., Grotzinger J.P., Grotzinger J.P., Hoffman P.F., Igor M. Gorokhov, Kaufman A.J., Kennedy M.J., Kirschvink J.L., Knoll A.H., Knoll A.H., Knoll A.H., Kupecz J.A., Kuznetsov A.B., Kuznetsov A.B., Lambert I.B., Magaritz M., McArthur J.M., McArthur J.M., McCulloch M.T., Melezhik V.A., Morton J.P., Ovchinnikova G.V., Pelechaty S.M., Podkovyrov V.N., Pokrovsky B.G., Pokrovsky B.G., Pokrovsky B.G., Saylor B.Z., Semikhatov M.A., Singh U., Smith L.H., Tronnes R.G., Tucker M.E., Tucker M.E., Veizer J., Veizer J., Victor A. Melezhik, Wada S.-I., Walter M.R., Wang Da-Rui   +55 more
core   +1 more source

Polychronous zircons of volcanics of the Navysh complex of the Lower Riphean Ai Formation (Southern Urals)

Georesursy, 2020
The volcanics of the Navysh complex of the Lower Riphean Ai Formation in the Southern Urals are well studied petrochemically and dated by several methods.
Artur A. Krasnobaev, Victor N. Puchkov, Nina D. Sergeeva, Sofia V. Busharina   +3 more
doaj   +1 more source

Paleomagnetism of Upper Vendian sediments from the Winter Coast, White Sea region, Russia: Implications for the paleogeography of Baltica during Neoproterozoic times [PDF]

, 2002
Paleomagnetic results from an Upper Vendian sedimentary sequence exposed along the White Sea shoreline, NW Russia are described. These classical exposures have been the subject of intense paleontological investigations due to their well-preserved ...
Alexander Iosifidi, Alexei Khramov, Bingen, Dalziel, Fedonkin, Fisher, Grazhdankin, Hargraves, Hoffman, Jennifer Tait, Kirschvink, Knoll, Martin, McCabe, McFadden, McKerrow, Meert, Meert, Piper, Piper, Pisarevsky, Poorter, Poorter, Powell, Smethurst, Sokolov, Storetvedt, Torsvik, Torsvik, Torsvik, Valerian Bachtadse, Van der Voo, Viktor Popov, Williams, Zijderveld   +34 more
core   +1 more source

Provenance reconstructions. Article 2. Litho- and isotope-geochemical approaches and methods

Литосфера, 2020
Research subject. In this paper, we consider specific features of the use of litho- and isotopic-geochemical data for the purposes of provenance reconstruction.Methods and materials.
A. V. Maslov, O. Yu. Melnichuk, G. A. Mizens, Yu. V. Titov, M. V. Chervyakovskaya   +4 more
doaj   +1 more source

TIME CONSTRAINTS ON THE FORMATION OF THE KANDALAKSHA AND KERETSK GRABENS OF THE WHITE SEA PALEO-RIFT SYSTEM FROM NEW ISOTOPIC GEOCHRONOLOGICAL DATA

Геодинамика и тектонофизика, 2021
Initially, the age and stratigraphic position of the Tersk formation were determined with respect to the fact that this formation overlaps the Early Proterozoic granitoids.
N. B. Kuznetsov, A. S. Baluev, E. N. Terekhov, S. Yu. Kolodyazhnyi, E. S. Przhiyalgovskii, T. V. Romanyuk, A. S. Dubensky, V. S. Sheshukov, S. M. Lyapunov, T. B. Bayanova, P. A. Serov   +10 more
doaj   +1 more source

Neoproterozoic Microfossils from the Margin of the East European Platform and the Search for a Biostratigraphic Model of Lower Ediacaran Rocks [PDF]

, 2010
A ca. 600 m thick siliciclastic succession in northern Russia contains abundant and diverse microfossils that document early to middle Ediacaran deposition along the northeastern margin of the East European Platform.
Knoll, Andrew Herbert, Sergeev, Vladimir N., Vorob’eva, Nataliya G.   +2 more
core   +1 more source

Reconstruction of the conditions for the formation of red-colored sandstones of the Tersky coast based on a comparative analysis of the structure of ancient and modern deposits (Kola Peninsula)

Vestnik MGTU, 2023
The paper presents the results of studying the Riphean red-colored sandstones of the Tersky coast of the White Sea. 21 structural elements characterizing the conditions of rock formation have been considered, including 15 ancient and 6 modern deposits ...
Neradovsky Yu. N.
doaj   +1 more source

⁸⁷Sr/⁸⁶Sr chemostratigraphy of Neoproterozoic Dalradian limestones of Scotland and Ireland: constraints on depositional ages and time scales [PDF]

, 2004
New calcite ⁸⁷Sr/⁸⁶Sr data for 47 limestones from the metamorphosed and deformed Neoproterozoic-Cambrian Dalradian Supergroup of Scotland and Ireland are used to identify secular trends in seawater <sup>
Ellam, R.M., Fallick, A.E., Graham, C.M., Thomas, C.W.   +3 more
core   +1 more source