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chert

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Journal Article
Journal: GSA Bulletin
Published: 05 February 2025
GSA Bulletin (2025) 137 (5-6): 2803–2822.
... analyses revealed various sizes of serpentinite, gabbro, basalt, chert, and oceanic-island/seamount and sandstone blocks, which represent a dismembered ophiolite and oceanic plate stratigraphy (OPS) above the ophiolite, in the matrix of deformed sandstones and siltstones. Geochemical analysis revealed...
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Journal Article
Journal: GSA Bulletin
Published: 08 January 2025
GSA Bulletin (2025) 137 (5-6): 2545–2564.
...Yu Yu; Liangbiao Lin; Qian Li; Gang Lu; Fengbin Liu; Fanchi Nan Abstract Unusual accumulations of chert developed worldwide over tens of millions of years during the Permian Period, and they are referred to as the Permian Chert Event. Middle Permian cherts, in the forms of nodules and bedded cherts...
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Journal Article
Journal: GSA Bulletin
Published: 20 December 2024
GSA Bulletin (2025) 137 (5-6): 2389–2406.
... the geology and genesis of the world’s largest wollastonite deposit (69.55 million tonnes [Mt] of wollastonite) at Shizhushan in the Mengshan district, South China. The wollastonite orebodies in the Shizhushan deposit are hosted by chert-bearing limestones within the Permian Makou Formation formed during...
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Journal Article
Published: 01 September 2024
Jour. Geol. Soc. India (2024) 100 (9): 1287–1298.
... mineral i.e., phosphorite in dolomite and carbonate-bearing chert in the Aravalli Supergroup. We applied feature-oriented principal component analysis to derive an image composite for delineating the spatial extent of carbonate rich zones within the Lunaveda Group of rocks. Subsequently, we used image...
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Journal Article
Journal: Geology
Published: 27 June 2024
Geology (2024) 52 (9): 706–711.
...Rosalie Tostevin; Serhat Sevgen Abstract Chert is abundant in Archean and Paleoproterozoic rocks and is commonly densely packed with authigenic Fe(II)-silicate nanoparticles such as greenalite, indicating a close relationship between iron and silica deposition. We investigate the relationship...
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Journal Article
Published: 20 June 2024
Bulletin de la Société Géologique de France (2025) 195 (1): 11.
... periglacial quartzite chert gypsum pseudomorphs France silicification périglaciaire grès calcaire silicifié pseudomorphose gypse France 1. pedogenic − formed on wide piedmont/glacis surfaces and resulting mainly from the alteration of clay materials by leaching of cations (relative...
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Journal Article
Published: 01 June 2024
Italian Journal of Geosciences (2024) 143 (2): 187–209.
... are the Ligurian Units and consist of ophiolites, shales, cherts and limestones of Jurassic to Eocene age, derived from the Ligure-Piemontese oceanic Domain. Within the Ligurian Units, the following tectonic units are distinguished in the study areas: a) the argille a Palombini Ophiolitic Unit derived from...
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Journal Article
Published: 01 June 2024
Italian Journal of Geosciences (2024) 143 (2): 213–225.
... dissection microscope revealed that it was made of strongly cemented sandstone, a lithology virtually absent in that particular alluvial terrace, which otherwise consists of medium-coarse gravel mostly made of limestone pebbles and rare chert clasts derived from the Jurassic-to-Eocene carbonate succession...
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Journal Article
Journal: GSA Bulletin
Published: 24 April 2024
GSA Bulletin (2024) 136 (11-12): 4761–4774.
..., radiolarian-bearing cherts, and volcanic-sedimentary units of various ages. A radiolarian-bearing volcanic-sedimentary unit exhibits a Bouma sequence, in which detrital zircons from a rhyolitic tuff and siliceous-clastic sedimentary rocks yielded youngest ages of 278–273 Ma, which constrain the depositional...
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Journal Article
Published: 26 February 2024
Geological Magazine (2023) 160 (10): 1946–1952.
...Sean McMahon; Corentin C. Loron; Laura M. Cooper; Alexander J. Hetherington; Michael Krings Abstract The ∼407-myr-old Rhynie chert of Scotland contains exquisite body fossils of land plants, animals and microorganisms, which provide our earliest reasonably complete snapshot of a Phanerozoic...
FIGURES
Journal Article
Published: 01 February 2024
Italian Journal of Geosciences (2024) 143 (1): 130–154.
... the post-Toarcian stratigraphy of the Longobucco Basin. The Trionto fm (siliciclastic/carbonate turbidites) of the Longobucco group is locally seen to change upward to grey limestones with black chert (Toarcian p.p. /Bajocian) characterized by Posidonia and bearing carbonate turbidites with shallow...
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Journal Article
Published: 01 January 2024
Russ. Geol. Geophys. (2024) 65 (1): 111–125.
..., and black cherts (silicites). Oil shales and mudstones have the highest organic matter content (average >15%, in some beds up to 35% of organic carbon per rock (C org ). Argillaceous limestones and black silicites contain up to 5% C org , and dolomitic limestones up to 3% C org . The complex...
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Series: EMU Notes in Mineralogy series
Publisher: Mineralogical Society of the United Kingdom and Ireland
Published: 01 January 2024
DOI: 10.1180/EMU-notes.21.7
EISBN: 9780903056687
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Journal Article
Published: 01 October 2023
Italian Journal of Geosciences (2023) 142 (3): 426–442.
... archaeological levels characterised by chert artefacts in primary position (flakes, blades, and cores). Moreover, in the lower part of the section, a palaeo-mudflow deposit within an alluvial conglomerate, contained a now-lost fossil of a human skull. These archaeological levels were radiocarbon dated suggesting...
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Journal Article
Journal: Geology
Published: 19 May 2023
Geology (2023) 51 (7): 683–687.
... (filamentous traits and stromatolites) in Precambrian cherts of Barberton, South Africa, and Gunflint, Canada. The botryoidal habits explored retained self-similar patterns of radially aligned acicular quartz with concentric laminae, which are not documented in biologically built stromatolites. These ancient...
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Journal Article
Published: 16 January 2023
Geological Magazine (2023) 160 (4): 712–731.
... Supplementary Material) is provided in Figure  5 . The samples from Poggio Peloso contain the highest Sb amounts found so far in chalcedonies. Table  5 shows a selection of reference data including chalcedony, carnelian and agate, as well as quartz, amethyst, chert/flint, jasper and quartzites from several...
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Journal Article
Journal: Geology
Published: 04 November 2022
Geology (2023) 51 (1): 33–38.
.... Context and morphology of Dresser Formation (Pilbara, Western Australia) stromatolites. (A) Geological map of the North Pole Dome locality. (B) Out-crop photograph showing finely layered stromatolites interbedded with chert-barite. (C) Hand sample with domical topography (arrowed). Stromatolitic...
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Journal Article
Published: 01 November 2022
Jour. Geol. Soc. India (2022) 98 (11): 1560–1566.
... and chert breccia. The geological setting, litho-stratigraphy and depositional environment of sediments have been studied by Jayaprakash et al. (1987 ) and Jayaprakash (2007 ). The petrographic, geochemical, geodynamic characteristics and depositional environments of arenites and shales have been widely...
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Journal Article
Journal: PALAIOS
Published: 15 September 2022
PALAIOS (2022) 37 (9): 486–498.
... windows that could entomb organic matter to preserve amorphous kerogen and even microbial body fossils before they could be extensively degraded. Some of the best examples of such preservation are found in early diagenetic chert that formed in peritidal environments. This chert contains discrete domains...
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Journal Article
Published: 10 June 2022
Geological Magazine (2022) 159 (10): 1699–1726.
... geochemistry. The topmost AU consists of ocean-island-like alkali basalts with seamount-derived Triassic shallow-marine limestones and Jurassic radiolarian cherts, which are stratigraphically overlain by Upper Cretaceous fore-arc turbidites. The base of the fore-arc sequence is palaeontologically...
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