Showing papers in "Precambrian Research in 2018"

TL;DR: The Nyong Complex of the Eburnian-Transamazonian orogen has been found to have a trace element pattern similar to those of mid-ocean ridge basalts, indicating that the precursor melts formed in a depleted mantle source as mentioned in this paper.

TL;DR: Zhang et al. as discussed by the authors reported new zircon U-Pb age and Hf-isotope as well as geochemical analyses of the recently discovered Archean-Paleoproterozoic Zhongxiang Complex in the northern-central Yangtze Craton, South China, and interpret the early crustal evolution of the Yangtse Craton.

TL;DR: In this paper, the authors carried out an integrated study of petrology, whole-rock geochemistry, as well as zircon morphology, trace element, U-Pb and Lu-Hf isotopes for granitic gneisses and leucogranites from the Yudongzi complex, a poorly studied Archean outcrop in the northwestern Yangtze Block.

TL;DR: In this paper, the authors presented new U-Pb ages, and the first Lu-Hf in zircon signatures from those complexes, ranging from c 2250 to c 1850.

TL;DR: In this paper, the start of the Cryogenian Period and the onset of the Sturtian Snowball Earth glaciation at ca. 717.4 ± 0.2 were investigated in the northern Wernecke Mountains of Canada.

TL;DR: The Borborema Province BP (NE Brazil) consists of a complex metasedimentary belts that amalgamate Archean-to-Paleoproterozoic gneiss-migmatite complexes as discussed by the authors.

TL;DR: The origin of magmatic episodes between final assembly and initial breakup of Rodinia is crucial for deciphering geodynamic transition and continental crust growth processes in the Tarim Craton as discussed by the authors.

TL;DR: Zhang et al. as discussed by the authors presented new field mapping results, U-Pb zircon ages, and geochemistry of the Paleoproterozoic rock sequence (i.e. volcano-sedimentary rocks and gneissic granites) from the Xiuyan area of the Central JLJB.

TL;DR: The first high precision U-Pb zircon age for the end Sturtian recorded in the Wilyerpa Formation of South Australia has been reported in this article, which supports previously published ages and is permissive with a globally synchronous deglaciation.

TL;DR: In this article, a combined study of zircon U-Pb isotopic data, whole-rock geochemistry and Sm-Nd isotope analyses are reported for these rocks to investigate their sources, petrogenesis and tectonic settings.

TL;DR: In this paper, the authors investigate the Konkanhundi gabbro-anorthosite suite from Peninsular India, adjacent to the major collisional suture between the Western and Eastern Dharwar cratonic blocks.

TL;DR: In this article, the early Cryogenian metamorphic magmatic rocks (including amphibolites and granitic gneisses) from the North Lhasa terrane of the central Tibetan plateau were reported.

TL;DR: In this article, the authors present a new estimate of early to middle Neoproterozoic (Tonian and Cryogenian) eukaryotic richness developed by use of the CONOP seriation algorithm; this approach permits inclusion of poorly dated and un-dated units and allows for greater resolution.

TL;DR: The Cassiterita Orthogneiss is the oldest pluton so far found within the Mineiro belt as discussed by the authors, with an in situ zircon U-Pb ages of between 2472 and 2414.

TL;DR: In this paper, the authors provided a new perspective to help resolve this problem by using three typical magmatic events marked by a 175 Ga charnockite, 164 Ga gabbro and 135 ga dolerite dykes in SW Siberia are identical with 175′Ga anorthosite, 163′ Ga basalt and 135'gabbro sills in the northern North China craton.

TL;DR: In this article, the authors presented a systematic study of petrology, geochemistry and geochronology of paragneisses and intermediate to basic intrusions from the Hualong Group, which represents the lower part of Precambrian basement of the block.

TL;DR: The Middle Marker horizon H1 of the Hooggenoeg Formation as discussed by the authors is the oldest sedimentary horizon in the Barberton greenstone belt and one of the earliest sedimentary horizons on Earth.

TL;DR: The Bougmane complex as mentioned in this paper is a Neoproterozoic tectonic unit located south of the Bou Azzer ophiolite in the Moroccan Anti-Atlas orogen.

TL;DR: In this article, the authors analyzed Cr-isotope and Ce-anomaly data of carbonates from the Ediacaran Doushantuo and Dengying formations in the Yangtze Gorges area, South China, in order to reconstruct oxygenation variations in the atmosphere and shallow seawaters of the YE during the Ediciaran Period.

TL;DR: Baddeleyite from a mafic dyke near Bhanupratappur of the central Bastar Craton (India) yielded a weighted-mean 207Pb/206Pb age of 1882.

TL;DR: In this paper, the authors used the LA-ICP-MS detrital zircon U-Pb age data to provide new age constraints on the upper Roper Group and reveal spatial and temporal provenance variations illustrating the evolution of the basin and its margins that are linked to a major provenance change caused by the coeval collision of the combined South Australian Craton/North Australian Crato with the West Australian craton.

TL;DR: Wang et al. as mentioned in this paper conducted systematic sedimentological analyses of six sections/cores of the Nantuo Formation, and three facies associations were recognized: the proximal glaciomarine, distal gliomarine and non-glacial marine facies association.

TL;DR: In this article, the authors report new U-Pb ages from Precambrian granites from boreholes in the Central Tarim Terrain (CTT) to constrain the timing of the assembly of the northern and southern Tarim terranes.

TL;DR: In this paper, the authors suggest that the ferroan (A-type) granitoids occurring in the north-eastern part of the Chotanagpur Granite Gneissic Complex (CGGC) are the results of melting of Palaeoproterozoic crust, triggered by mantle upwelling and increased heat transfer resulting from crustal extension associated to the fragmentation of the Indian landmass during the breakdown of the Columbia supercontinent.

TL;DR: In this article, the authors focus on the timing of magmatism and metamorphism, as well as on the thermal metamorphic conditions of garnet-free UHT granulites of the Guaxupe nappe, southernmost Brasilia orogen, located close to the Paranapanema cratonic block.

TL;DR: In this paper, the first evidence for Ediacaran magmatic rocks, including gabbros, tonalites, and rhyolites, were reported in the North Lhasa terrane, Tibet, and they were interpreted as a result of the Andean-type subduction along the Gondwanan Proto-Tethyan margin.

TL;DR: Zhang et al. as mentioned in this paper employed geochronology and Hf isotopic compositions of three newly discriminated gneissic granitoids in the Hongshuihe, Dangennaomuru and south Bokalike areas to elucidate the Neoproterozoic tectonics of EKO.

TL;DR: The Andrelândia Nappe System migration was probably restricted to the 635-600 Ma interval, followed by the thinning of the orogenic crust as discussed by the authors.

TL;DR: In this article, high-K granitoids were found to have meta-to peraluminous characteristics in the A/NK versus A/CNK plots in the TAS classification diagram and in the SiO2 and K2O diagram.

TL;DR: The Spektakel Suite has geochemical and isotopic compositions suggesting that it was derived from recycled Palaeoproterozoic crust with Mesoprotechnology input as mentioned in this paper.