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ejecta

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Journal Article
Journal: Economic Geology
Published: 01 May 2020
Economic Geology (2020) 115 (3): 505–525.
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Journal Article
Published: 17 January 2020
Journal of the Geological Society (2020) 177 (2): 449–451.
.... Their lithic clast provenance approach is novel but it is vital to specify the context of individual clasts. Spallation ejecta beneath the impact deposit may have a different source from clasts within it yet both may originate from the same basement terrain if movement is from east to west, along-strike...
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Journal Article
Published: 17 January 2020
Journal of the Geological Society (2020) 177 (2): 452–454.
... and 2 ). Our observations of the disrupted pre-existing sedimentary strata suggest that little information can be gained on the direction the impact ejecta travelled. The sandstone raft noted by Simms does indeed have over-steepened beds but it is unclear whether it is still attached to the strata...
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Journal Article
Published: 13 December 2019
Journal of the Geological Society (2020) 177 (2): 447.
... ) was based largely on field observations that, amongst other things, indicated that the Stac Fada Member impact ejecta preserved at outcrop had come from the east (despite claims to the contrary by others; Amor et al. 2008 , 2019 ). When subsequently I became aware of the LGL I realized that its location...
Journal Article
Published: 13 December 2019
Journal of the Geological Society (2020) 177 (2): 443–446.
... of the Stoer Group of NW Scotland as a proximal ejecta blanket of late Mesoproterozoic age ( Amor et al. 2008 ) has led to the search for the impact crater from which it originated. One prominent suggestion has been that this crater lies buried beneath east-central Sutherland, broadly centred on the village...
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Journal Article
Published: 01 April 2019
American Mineralogist (2019) 104 (4): 611–614.
... uncertain. Hydrogen has profound effects on properties and processes on microscopic-to-global scales. Here we report the discovery of the first hydride (VH 2 ) ever reported in nature. This phase has been found in the ejecta of Cretaceous pyroclastic volcanoes on Mt Carmel, N. Israel, which include abundant...
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Series: GSA Field Guide
Published: 10 December 2018
DOI: 10.1130/2018.0051(17)
EISBN: 9780813756516
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Journal Article
Published: 27 November 2018
Journal of the Geological Society (2019) 176 (2): 209–224.
... and remobilization of ejecta blankets from major meteorite impact events, before returning to background after some hundreds to thousands of years. We review the 44 largest confirmed craters and evaluate the potassium feldspar content of their target rocks, which range from c. 0 to >30%. By combining crater size...
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Journal Article
Journal: Geology
Published: 19 July 2018
Geology (2018) 46 (9): 739–742.
.... The actual mechanism whereby coesite forms in these symplectic regions, i.e., direct transformation from quartz or crystallization from hot silica melts jetted into the collapsing pore ( Kieffer et al., 1976 ), is still unclear. Symplectic regions were identified in shocked sandstone ejecta samples from...
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Journal Article
Journal: Geology
Published: 20 December 2017
Geology (2018) 46 (3): 203–206.
... of the source crater. 13 09 2017 22 11 2017 27 11 2017 © 2017 Geological Society of America 2017 Tektites are glassy impact ejecta that are important for understanding impact processes, as they occur over widely dispersed “strewn fields”, and can preserve geochemical information...
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Journal Article
Journal: Geology
Published: 12 December 2017
Geology (2018) 46 (2): 171–174.
.... However, it is highly unusual to find unmelted crystals from the actual impactor within an ejecta layer. Here we detail the first recorded occurrence of vanadium-rich osbornite (TiVN) on Earth, from two sites on Skye, northwest Scotland, which are interpreted as part of a meteoritic ejecta layer. TiVN has...
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Journal Article
Journal: Geology
Published: 03 October 2017
Geology (2017) 45 (12): 1063–1066.
... is reached, ballistic trajectories are calculated for ejecta using tracer velocities. The trajectories determine when and where material will be emplaced outside of the elliptical transient crater. Inside the rim of the final ∼2500-km-diameter elliptical crater but outside the transient crater, post...
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Journal Article
Published: 14 August 2017
Geological Magazine (2019) 156 (1): 1–24.
... . 3.7 km diameter crater with a well-preserved ejecta blanket. It has been hypothesized to be either of impact or volcanic origin in our previous work. Observations during our 2007 expedition and related sample analyses give further support for an impact origin. The evidence includes the presence...
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Journal Article
Journal: Geology
Published: 01 October 2016
Geology (2016) 44 (10): 811–814.
... of an eruption, explosion mechanisms, and ultimately hazards associated with an eruption, it is important to recognize the contribution of recycled clasts to ejecta deposits ( Houghton and Smith, 1993 ). Recycling can involve individual juvenile or lithic clasts, clasts composed of a combination of the two...
Journal Article
Journal: Geology
Published: 01 July 2016
Geology (2016) 44 (7): 519–522.
...Jennifer L. Whitten; Bruce A. Campbell Abstract Ejecta from impact craters on Venus are a major source of fine-grained materials across the planet, and crater spatial distribution has been studied as a guide to the relative age and resurfacing rates of large regions. Of particular interest...
Journal Article
Journal: Geology
Published: 01 March 2016
Geology (2016) 44 (3): 195–198.
..., but between magma and a water-saturated slurry of previously erupted ejecta that fills the vent. We examined hundreds of blocks and bombs on Surtsey (63°18′N, 20°36′W) during fieldwork in 2013 and 2014. The blocks consist of xenolithic seafloor sedimentary rock (estimated 15% of total), and dike...
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Journal Article
Published: 01 November 2015
American Mineralogist (2015) 100 (11-12): 2426–2442.
... produced a range of experimental and theoretical data sets on bubble nucleation, growth, and coalescence in magmatic systems. A robust experimental database is required to calibrate (theoretical and empirical) modeling approaches, which allow the calculation of magma ascent rates from volcanic ejecta...
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Series: GSA Special Papers
Published: 01 October 2015
DOI: 10.1130/2015.2518(03)
... This study compares results of crater diameter, shape, ejecta morphologies, and interior morphologies in the northern hemisphere of Mars between older results reported from a Viking -derived crater catalog and a new crater catalog obtained from analysis of higher-resolution data sets...
Journal Article
Journal: Geology
Published: 01 April 2015
Geology (2015) 43 (4): 299–302.
... asteroid impacts on Earth. Spherules in these layers are interpreted as molten impact ejecta, condensation products from impact plumes, or impact ejecta melted during atmospheric reentry. Past research has shown that some spherule layer samples from the BGB carry ultrahigh abundances of siderophile...
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Journal Article
Journal: Geology
Published: 01 March 2015
Geology (2015) 43 (3): 251–254.
...Bruce M. Simonson; Steven Goderis; Nicolas J. Beukes Abstract Thin layers rich in formerly molten spherules interpreted as distal ejecta from large impacts by extraterrestrial bodies have been found in 8 stratigraphic units deposited between ca. 2.63 Ga and 2.49 Ga and attributed to a minimum of 4...
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