Results 61 to 70 of about 829 (171)

Variable Sr Diffusion and Implications for Rb–Sr Biotite Geochronology

Journal of Metamorphic Geology, Volume 44, Issue 6, Page 417-439, July 2026.
ABSTRACT The rubidium–strontium (Rb–Sr) system has a long pedigree as a geochronological tool that relies on the application of an isochron approach. In particular, biotite contains strongly radiogenic Rb–Sr isotopes, and thus can yield meaningful crystallisation or cooling ages via this approach. However, the response of the Rb–Sr system in biotite to
Riley Rohrer, Christopher L. Kirkland, Hugo Olierook, Tim Johnson, Katy Evans   +4 more
wiley   +1 more source

Geology of the central uplift of the Kamestastin Lake impact structure, Labrador, Canada

Meteoritics &Planetary Science, Volume 61, Issue 7, Page 1417-1433, July 2026.
Abstract The ~28 km Kamestastin (Mistastin) Lake impact structure is a relatively well‐preserved and well‐exposed complex impact structure. The central uplift of this structure is accessible as two islands in the middle of Kamestastin Lake. We present an updated, detailed geological map and description of Horseshoe and Bullseye islands that provides ...
A. C. Singleton, G. R. Osinski
wiley   +1 more source

Highly fractionated chromium isotopes in Mesoproterozoic-aged shales and atmospheric oxygen

Nature Communications, 2018
There is a long standing debate whether low atmospheric oxygen levels during the Mesoproterozoic Era hindered the evolution of crown-group animals. Here, the authors show with shale-hosted chromium isotopes that sufficient atmospheric oxygen for crown ...
Donald E. Canfield, Shuichang Zhang, Anja B. Frank, Xiaomei Wang, Huajian Wang, Jin Su, Yuntao Ye, Robert Frei   +7 more
doaj   +1 more source

New Detrital Zircon Age of the Paleo-Mesoproterozoic Xiong’er Group, Southern North China Craton

Frontiers in Earth Science, 2021
Xiaoguang Liu, Xiaoguang Liu
doaj   +1 more source

Weathering in a world without terrestrial life recorded in the Mesoproterozoic Velkerri Formation

Nature Communications, 2019
Prior to the expansion of life on to land, abiotic weathering may have resulted in different boundary conditions affecting the composition of the biosphere.
Mehrnoush Rafiei, Martin Kennedy
doaj   +1 more source

The United States Magnetotelluric Array and the National Impedance Map

Reviews of Geophysics, Volume 64, Issue 2, June 2026.
Abstract The United States Magnetotelluric Array (USMTArray) data set, collected in the years 2006–2024, consists of more than 1,700 long‐period magnetotelluric stations covering the entirety of the contiguous United States on a quasi‐regular 70 km grid.
Anna Kelbert, Paul A. Bedrosian, Adam Schultz, Gary D. Egbert, Louise Pellerin, Jeffrey J. Love, Andrew Frassetto, Benjamin S. Murphy   +7 more
wiley   +1 more source

Early Mesoproterozoic sedimentary-volcanic sequence in the Ordos Basin, North China Craton: A possible link to the breakup of the Columbia supercontinent and implications for hydrocarbon exploration

Energy Exploration & Exploitation
In the Jinshan aulacogen on the southern margin of the Ordos Basin, volcanic rocks of the Mesoproterozoic Changchengian System Xiong'er Group were first encountered by Well PT1, and the drilling operations have revealed the complete strata of ...
Xing Pan, Gang Liu, Hai-feng Bai, Lei Zhang, Jian-wu Zhang, Xiang-hui Jing, Jun-feng Ren, Xiao-qing Pan   +7 more
doaj   +1 more source

Tectonic evolution of the southern margin of the Amazonian craton in the late Mesoproterozoic based on field relationships and zircon U-Pb geochronology

Anais da Academia Brasileira de Ciências, 2014
New U-Pb zircon geochronological data integrated with field relationships and an airborne geophysical survey suggest that the Nova Brasilândia and Aguapeí belts are part of the same monocyclic, metaigneous and metasedimentary belt formed in the late ...
GILMAR J. RIZZOTTO, LÉO A. HARTMANN, JOÃO O.S. SANTOS, NEAL J. MCNAUGHTON   +3 more
doaj   +1 more source

Recently Identified Mesoproterozoic Strata in South‐Central Idaho Document Late‐Stage Rifting of the Nuna Supercontinent in Western Laurentia

Geochemistry, Geophysics, Geosystems
Sedimentary basins are valuable archives of tectonic processes involved in continental rifting. The northern Rocky Mountains preserve the Belt Supergroup, one of the most complete records of Mesoproterozoic strata on Earth; however, debate remains about ...
J. P. Lever, K. E. Sundell, D. M. Pearson, D.T. Brennan   +3 more
doaj   +1 more source

Environment controls on Mesoproterozoic thrombolite morphogenesis: A case study from the North China Platform

Journal of Palaeogeography, 2013
Thrombolites are widespread in the Mesoproterozoic Wumishan Formation in the North China Platform. This study shows that they mainly concentrated in subtidal carbonate facies with relatively low hydrodynamic conditions, rather than in intertidal zone as ...
Tang Dongjie, Shi Xiaoying, Jiang Ganqing, Pei Yunpeng, Zhang Wenhao   +4 more
doaj   +1 more source