Results 31 to 40 of about 61,505 (248)

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

Earth's middle age [PDF]

, 2014
This research was funded through Natural Environment Research Council (grant NE/J021822/1) and the APC was paid through the RCUK OA block grant.Earth's middle age, extending from 1.7 to 0.75 Ga, was characterized by environmental, evolutionary, and ...
Cawood, Peter Anthony, Hawkesworth, Chris   +1 more
core   +1 more source

The Lomagundi-Jatuli carbon isotopic event recorded in the marble of the Tandilia System basement, Río de la Plata Craton, Argentina [PDF]

, 2019
The “Lomagundi-Jatuli event” corresponds to the most important δ13C positive anomaly (≥5‰) globally reported in Palaeoproterozoic marine carbonates (between ∼2.30 and 2.06 Ga).
Ballivian Justiniano, Carlos Alberto, Cingolani, Carlos Alberto, Etcheverry, Ricardo Oscar, Lajoinie, Maria Florencia, Lanfranchini, Mabel Elena, Recio, C., Sial, A.N.   +6 more
core   +1 more source

MAIN STAGES OF CONTINENTAL CRUST FORMATION IN THE WESTERN ALDAN SHIELD: CONSTRAINTS FROM SM-ND ISOTOPE SYSTEMATICS OF CENOZOIC SANDS IN THE CHARA AND TOKKA BASINS

Геодинамика и тектонофизика, 2017
Previous geochronological and Sm-Nd isotopegeochemical studies have identified the main stages of the Precambrian continental crust formation in the central and eastern parts of the Aldan Shield [Kotov et al., 2006], while its western part (Chara-Olekma ...
A. B. Коtоv, T. M. Skovitina, V. P. Kovach, S. D. Velikoslavinsky, D. V. Lopatin, E. V. Sklyarov, E. V. Tolmacheva, O. V. Bobrovskaya   +7 more
doaj   +1 more source

Thermochronologic Constraints on the Extensional History of the Ibex Hills, Southeastern Black Mountains, Death Valley, California

Geological Journal, EarlyView.
A. Modeled T‐t paths for samples in the northern Ibex Hills, showing steady cooling throughout much of the Cenozoic, until rapid Miocene cooling. B. Weighted mean paths for each sample in this study. Note that all show a rapid cooling event at or just after 10 Ma, which is interpreted to represent exhumation as a result of regional extenstion ...
Zachariah D. Fleming
wiley   +1 more source

An airborne geophysical survey of part of west Dyfed, South Wales, and some related ground surveys [PDF]

, 1986
A detailed airborne geophysical survey has been made of part of west Dyfed at a flying height of 75 m with magnetic, electromagnetic (VLF-EM) and radiometric equipment mounted in a helicopter.
Cave, R., Cornwell, J.D.
core  

Fossil biomass preserved as graphitic carbon in a late paleoproterozoic banded iron formation metamorphosed at more than 550°C [PDF]

, 2019
Metamorphism is thought to destroy microfossils, partly through devolatilization and graphitization of biogenic organic matter. However, the extent to which there is a loss of molecular, elemental and isotope signatures from biomass during high ...
De Gregorio, BT, Drost, M, Kilcoyne, DA, Marbach, H, Nittler, L, Papineau, D, Sagar, J, Thornton, G, Thorogate, R, Wang, J   +9 more
core   +2 more sources

Notable Impact of Paleotectonic Stress on Gold Mineralisation in the West Qinling Orogen

Geological Journal, EarlyView.
By applying fuzzy clustering and multiple inverse methods, we systematically processed the data of vein and fault slip in this ore deposit to reveal the transition of orogenic geological environment and paleotectonic stress field. Our research results show two different stress states: the northwest–southeast extensional stress field and the northeast ...
Hongyan Wang, Aibing Chen, Jian Yang, Yuan Zhang   +3 more
wiley   +1 more source

Carbonate alteration of ophiolitic rocks in the Arabian–Nubian Shield of Egypt: sources and compositions of the carbonating fluid and implications for the formation of Au deposits [PDF]

, 2016
Ultramafic portions of ophiolitic fragments in the Arabian–Nubian Shield (ANS) show pervasive carbonate alteration forming various degrees of carbonated serpentinites and listvenitic rocks.
Azer, Mokhles K., Boskabadi, Arman, Boyce, Adrian, Broman, Curt, Cooper, Matthew J., Majka, Jaroslaw, Mohamed, Fathy H., Pitcairn, Iain K., Stern, Robert J., Teagle, Damon A.H.   +9 more
core   +2 more sources

Raman Line Scan Analyses and a New Hypothesis for the Formation of Anatase‐Hosting Microbialites: Study of the Stromatolites From Saint‐Jean‐de‐la‐Rivière, Cotentin, France

Journal of Raman Spectroscopy, EarlyView.
Micrometer analysis of millimeter lines of Raman spectra concludes in the association of anatase and graphitized organic matter (graphogen). The photosynthetic microorganisms at the origin of the microbialites produce O2, which is transformed by TiO2 into reactive species that, in turn, decompose the organic matter of the microorganisms. ABSTRACT Raman
Marie‐Paule Bassez
wiley   +1 more source