Showing 1 - 20 results of 712 for search '"Proterozoic"', query time: 0.20s Refine Results
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    Enigmatic Mid‐Proterozoic Orogens: Hot, Thin, and Low by Christopher J. Spencer, Ross N. Mitchell, Michael Brown

    Published 2021-08-01
    “…Alternatively, secular change in crustal thickness is attributed to orogenic style, namely the prevalence of hot, thin, and low orogens in the mid‐Proterozoic.…”
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    Proterozoic, Archeam and other weeds in the Precambrian rock garden by K. Rankama

    Published 1970-12-01
    “…The use of the terms Precambrian; Proterozoic, Algonkian, and Archean; Cryptozoic and Archeozoic; and Eocambrian, Infracambrian, and Subcambrian is discussed. …”
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    Morphometric convergence between Proterozoic and post-vegetation rivers by Alessandro Ielpi, Robert H. Rainbird, Dario Ventra, Massimiliano Ghinassi

    Published 2017-05-01
    “…It has been previously assumed that deep river channels could not have developed in the Proterozoic due to lack of vegetation. Here, the authors present remote sensing and outcrop data to show that large scale and deeply channelled river networks did exist in the Proterozoic despite the absence of vegetation.…”
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    Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans by Bing Shen, Lin Dong, Shuhai Xiao, Xianguo Lang, Kangjun Huang, Yongbo Peng, Chuanming Zhou, Shan Ke, Pengju Liu

    Published 2016-01-01
    “…Molar tooth structures are common in early- to mid-Proterozoic carbonates but extremely rare in rocks younger than 750 Ma. …”
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    CO-EVOLUTION OF PROTEROZOIC CRATONIC FRAGMENTS IN WESTERN AND NORTHERN MONGOLIA by Uyanga Bold, Francis Macdonald, Yukio Isozaki

    Published 2017-09-01
    “…In order to better constrain Precambrian tectonic evolution of the CAOB, it is important to revisit Precambrian terranes of Mongolia as outlined in Badarch et al. [2002] that contain Archean to Proterozoic metamorphic basement and Neoproterozoic metasedimentary and volcanic rocks.…”
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    Microbial communities and organic biomarkers in a Proterozoic-analog sinkhole by Hamilton, T. L., Welander, P. V., Albrecht, H. L., Fulton, J. M., Schaperdoth, I., Bird, L. R., Freeman, K. H., Macalady, J. L., Summons, Roger E

    Published 2018
    “…Our results indicate that the mats carry out light-driven primary production in the absence of oxygen production—a mechanism that may have delayed the oxygenation of the Earth's oceans and atmosphere during the Proterozoic Eon. Furthermore, our observations of the production of 2-methyl hopanoids by Cyanobacteria under conditions of low oxygen and low light are consistent with the recovery of these structures from ancient black shales as well as their paucity in modern marine environments.…”
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    Niche expansion for phototrophic sulfur bacteria at the Proterozoic–Phanerozoic transition by Cui, Xingqian, Liu, Xiao-Lei, Shen, Gaozhong, Ma, Jian, Husain, Fatima, Rocher, Donald, Zumberge, John E, Bryant, Donald A, Summons, Roger E

    Published 2021
    “…The cyanobacterial carotenoid synechoxanthin, and its immediate biosynthetic precursors, contain thermally labile, aromatic carboxylic-acid functional groups, which upon hydrogenation and mild heating yield mixtures of products that closely resemble those found in the Proterozoic fossil record. The Neoproterozoic–Phanerozoic transition in fossil carotenoid patterns likely reflects a step change in the surface sulfur inventory that afforded opportunities for the expansion of phototropic sulfur bacteria in marine ecosystems. …”
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    Niche expansion for phototrophic sulfur bacteria at the Proterozoic–Phanerozoic transition by Cui, Xingqian, Liu, Xiao-Lei, Shen, Gaozhong, Ma, Jian, Husain, Fatima, Rocher, Donald, Zumberge, John E, Bryant, Donald A, Summons, Roger E

    Published 2022
    “…The cyanobacterial carotenoid synechoxanthin, and its immediate biosynthetic precursors, contain thermally labile, aromatic carboxylic-acid functional groups, which upon hydrogenation and mild heating yield mixtures of products that closely resemble those found in the Proterozoic fossil record. The Neoproterozoic–Phanerozoic transition in fossil carotenoid patterns likely reflects a step change in the surface sulfur inventory that afforded opportunities for the expansion of phototropic sulfur bacteria in marine ecosystems. …”
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    On the enigmatic mid-Proterozoic: Single-lid versus plate tectonics by Roberts, NMW, Salminen, J, Johansson, Å, Mitchell, RN, Palin, RM, Condie, KC, Spencer, CJ

    Published 2022
    “…In our reappraisal of the mid-Proterozoic geological record, we not only assess the viability of the single-lid hypothesis for each line of evidence, but also that of the plate tectonic alternative. …”
    Journal article
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    Molybdenum isotope evidence for widespread anoxia in mid-Proterozoic oceans. by Arnold, G, Anbar, A, Barling, J, Lyons, T

    Published 2004
    “…How much dissolved oxygen was present in the mid-Proterozoic oceans between 1.8 and 1.0 billion years ago is debated vigorously. …”
    Journal article