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glendonite

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Journal Article
Published: 18 March 2024
Journal of Sedimentary Research (2024) 94 (2): 179–206.
... The type locality for the upper Oligocene Nuwok Member of the Sagavanirktok Formation (Carter Creek, North Slope, Alaska, USA) contains an abundant occurrence of glendonite, a pseudomorph after the calcium-carbonate mineral ikaite, which typically forms in the shallow subsurface of cold marine sediments...
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Journal Article
Published: 03 October 2022
American Mineralogist (2022) 107 (10): 1960–1967.
.... This mineral is metastable and quickly transforms to calcite at temperatures above 5 °C. Pseudomorphs of calcite after ikaite are known as glendonite. The nanostructure of 25 000–43 000 year old glendonite from Victoria cave (Southern Ural, Russia) was investigated in search of structural features indicative...
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First thumbnail for: Tracing structural relicts of the ikaite-to-calcit...
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Journal Article
Journal: GSA Bulletin
Published: 01 July 2017
GSA Bulletin (2017) 129 (7-8): 771–787.
...Stephen E. Grasby; Gennyne E. McCune; Benoit Beauchamp; Jennifer M. Galloway Abstract Dramatic global climate change in the Early Cretaceous suggests that numerous boreal cool events perturbed otherwise warm conditions. Abundant glendonites in Valanginian and Aptian strata are thought to be key...
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First thumbnail for: Lower Cretaceous cold snaps led to widespread <spa...
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Journal Article
Journal: Geology
Published: 01 June 2017
Geology (2017) 45 (6): 575–576.
... maintained and the product is referred to as glendonite. Glendonite is consequently not a mineral but a pseudomorph of calcite after ikaite. Both ikaite and glendonite have been known for a long time, but the derivation of glendonite from ikaite was only confirmed after crystal aggregates of ikaite...
Journal Article
Journal: Geology
Published: 01 June 2017
Geology (2017) 45 (6): 503–506.
... warming events associated with major carbon cycle perturbations. Paradoxically, many of these extreme greenhouse episodes are preceded or followed by cold climate, perhaps even glacial conditions, as inferred from the occurrence of glendonites in high latitudes. Glendonites are pseudomorphs of ikaite...
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Journal Article
Journal: GSA Bulletin
Published: 19 February 2025
GSA Bulletin (2025) 137 (7-8): 2999–3010.
... in the geological past is very limited due to the paucity of insights that this compound leaves in the rock record after its destabilization. Calcite pseudomorphs after ikaite (CaCO 3 ·6H 2 O), also known as glendonites, are here documented in Oligocene seep carbonates from the Outer Carpathians in southern Poland...
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Journal Article
Journal: Geology
Published: 01 February 2017
Geology (2017) 45 (2): 115–118.
... and paleobiological data are shaping current understanding of Ediacaran evolutionary and environmental history. Here, we report the occurrence of silicified glendonites in the Ediacaran Doushantuo Formation deposited in an inner-shelf environment on the South China block. Petrographic evidence suggests...
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Journal Article
Published: 01 November 2001
American Mineralogist (2001) 86 (11-12): 1530–1533.
...Ian P. Swainson; Robert P. Hammond Abstract Neutron diffraction results are linked to the pre-diffraction, morphological crystallography of E.S. Dana to show that ikaite is the precursor of “glendonite” and “thinolite” and that some of the unusual features of the morphology can easily be explained...
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First thumbnail for: Ikaite, CaCO 3 ·6H 2 O: Cold comfort for <span cla...
Second thumbnail for: Ikaite, CaCO 3 ·6H 2 O: Cold comfort for <span cla...
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Optical characteristics of the studied glendonites and host concretions in plane-polarized light. A) Sample Sn-1 (glendonite). B) Sample Bal-6 (glendonite). C) Sample Bal-2 (Glend, glendonite; Conc, host concretion). D) Sample Bal-4 (host concretion). White arrows point at needle-like calcite crystals at the edge of a glendonite blade, yellow arrows point at dark central zones of the glendonite-composing crystals.
Published: 27 June 2024
Fig. 5. Optical characteristics of the studied glendonites and host concretions in plane-polarized light. A) Sample Sn-1 (glendonite). B) Sample Bal-6 (glendonite). C) Sample Bal-2 (Glend, glendonite; Conc, host concretion). D) Sample Bal-4 (host concretion). White arrows point at needle
Journal Article
Published: 01 September 2001
South African Journal of Geology (2001) 104 (3): 265–272.
...I. R. McLachlan; H. Tsikos; B. Cairncross Abstract Glendonites are carbonate pseudomorphs after monoclinic crystals of ikaite (calcium carbonate hexahydrate: CaCO 3 .6H 2 O). Ikaite forms at present within organic-rich marine or brackish sediments that are at near freezing temperatures...
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Stable-isotope data plot of glendonite calcite and related materials. S brach = brachiopods from Sydney Basin strata containing glendonites; S bulk = Sydney Basin bulk glendonite calcite; T bulk = Tasmania Basin bulk glendonite calcite; S amber = Sydney Basin glendonite amber-brown calcite handpicked separate; T amber = Tasmania Basin glendonite amber-brown calcite handpicked separate; S clear = Sydney Basin glendonite clear-white calcite handpicked separate; T clear = Tasmania Basin glendonite clear-white calcite handpicked separate; S spar = Sydney Basin hydrothermal calcite; Bowen = Bowen Basin glendonite data from Huggett et al. (2005).
Published: 01 November 2007
Figure 5 Stable-isotope data plot of glendonite calcite and related materials. S brach = brachiopods from Sydney Basin strata containing glendonites; S bulk = Sydney Basin bulk glendonite calcite; T bulk = Tasmania Basin bulk glendonite calcite; S amber = Sydney Basin glendonite amber-brown
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Mineralogical maps of glendonite interiors, showing distribution of calcite types in crystals and corresponding polished reflected-light images. A) Small Type A glendonite, cut perpendicular to crystal long axis. B) Same specimen as Part A, cut parallel to long axis of primary crystal. C, D) Cross sections of large Type A glendonites, cut perpendicular to long axis of crystal, found in situ at 55 m. E) Type B glendonite, cut perpendicular to long axis of crystal.
Published: 18 March 2024
Fig. 9. Mineralogical maps of glendonite interiors, showing distribution of calcite types in crystals and corresponding polished reflected-light images. A) Small Type A glendonite, cut perpendicular to crystal long axis. B) Same specimen as Part A, cut parallel to long axis of primary crystal
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Pseudomorphic glendonites from the Doushantuo Formation (China). A: Stellate cluster of glendonite in thin section. B–D: Mg, P, and Si elemental maps of rectangle in A, with brighter colors denoting greater relative concentrations. E–G: Incompletely silicified glendonites in polished slabs (E–F) and thin section (G), showing warping sedimentary laminae and pore spaces in glendonites filled with phosphatic dolostone sediments (E). A stringer of phosphatic sediments extends into glendonite in G (red arrow). Black granules are phosphatic intraclasts. H: Microscopic stellate glendonite in thin section, showing pyramidal crystal terminations (yellow arrows). I, J: Hand samples of stellate clusters of glendonites on bedding surface (I) and in vertical cross section (J). K: X-ray microcomputed tomography reconstruction of an unexposed stellate glendonite cluster in a drill-core sample (Figs. DR2H and DR2I [see footnote 1]), with bedding surface (x*y) parallel to plane of view. Twinning angles are marked with dotted lines.
Published: 01 February 2017
Figure 2. Pseudomorphic glendonites from the Doushantuo Formation (China). A: Stellate cluster of glendonite in thin section. B–D: Mg, P, and Si elemental maps of rectangle in A, with brighter colors denoting greater relative concentrations. E–G: Incompletely silicified glendonites in polished
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Comparison of δ13С and δ18O stable isotopes of glendonites from the Kobyume River (Siberia) section, at the river cut exposure, with those from the Permian of eastern Australia (Frank et al., 2008, 2015) and with isotopes of Cretaceous glendonites from Siberia (Rogov et al., 2017). Isotopically, glendonites from the Kobyume River are similar to Permian glendonites in eastern Australia, but do not overlap Cretaceous samples; the latter are less altered than the former. Photo shows glendonites from the upper Lugovaya Formation, sample 19VD35 (#16 in the table), collected at 1812 m. carb—carbonate; V-PDB—Vienna Peedee belemnite; TOC—total organic carbon.
Published: 26 April 2022
Figure 4. Comparison of δ 13 С and δ 18 O stable isotopes of glendonites from the Kobyume River (Siberia) section, at the river cut exposure, with those from the Permian of eastern Australia ( Frank et al., 2008 , 2015 ) and with isotopes of Cretaceous glendonites from Siberia ( Rogov et al
Journal Article
Published: 27 June 2024
Journal of Sedimentary Research (2024) 94 (4): 355–366.
...Fig. 5. Optical characteristics of the studied glendonites and host concretions in plane-polarized light. A) Sample Sn-1 (glendonite). B) Sample Bal-6 (glendonite). C) Sample Bal-2 (Glend, glendonite; Conc, host concretion). D) Sample Bal-4 (host concretion). White arrows point at needle...
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Morphology of the studied glendonites. W, wood fragment; G, glendonite; C, carbonate concretion; Sh, bivalve shell fragment.
Published: 27 June 2024
Fig. 3. Morphology of the studied glendonites. W, wood fragment; G, glendonite; C, carbonate concretion; Sh, bivalve shell fragment.
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Photomicrographs (plane light) of glendonite and associated sediment. Wandrawandian Siltstone, Sydney Basin, NSW. A) Section of glendonite illustrating displacive growth of original ikaite crystal. Note abundant bioclasts. Scale in mm. B) Interior of glendonite illustrating darker (amber-brown) calcite with lighter clear-white calcite cement. Scale in mm. C) Glendonite with included bioclasts. Scale in mm. D) Bioclastic siltstone. Note Ca-phosphate infill of spines and punctae (arrows).
Published: 01 November 2007
Figure 4 Photomicrographs (plane light) of glendonite and associated sediment. Wandrawandian Siltstone, Sydney Basin, NSW. A) Section of glendonite illustrating displacive growth of original ikaite crystal. Note abundant bioclasts. Scale in mm. B) Interior of glendonite illustrating darker
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Macroscopic and microscopic views of glendonite specimens from Siberia (Russia). A,B: Medium-size stellate-shape glendonite; upper Pliensbachian, profile and transverse views, respectively. C,D: Succession of carbonate cements observed in glendonites (Ros—rosette oriented crystals; Rov—rosette calcite overgrowths; Bot—botryoids); upper Bajocian, transmitted and ultraviolet light (UV), respectively. Rosettes contain black UV-fluorescent impurities resulting from organic particles. Some botryoidal carbonates have highly fluorescent rim that may be due to microbial film. E: Fluid exhaust microstructure associated with dissolution event (DE) disbanding rosette overgrowths (Rov) of glendonite and reworking nonconsolidated host sediment (Sed); upper Bajocian. F: Conglomerate of reworked and broken glendonites containing rosette overgrowths (Rov) in sandy matrix with crinoid fragments (Cr), and highlighting early fossilization of ikaite; upper Bajocian.
Published: 01 June 2017
Figure 2. Macroscopic and microscopic views of glendonite specimens from Siberia (Russia). A,B: Medium-size stellate-shape glendonite; upper Pliensbachian, profile and transverse views, respectively. C,D: Succession of carbonate cements observed in glendonites (Ros—rosette oriented crystals; Rov
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Measured stratigraphic sections through glendonite-bearing horizons in the Deer Bay (DB1) and Christopher Formations (CH1 and CH2) exposed on Ellef Ringnes Island (locations are shown in Fig. 3). Mudstone is subdivided on the basis of texture (related to silt content) and weathering profile in outcrop. Carbonaceous mudstones, concretions, and nodules, and glendonite occurrences are shown. Glendonite-bearing horizons are highlighted in gray.
Published: 01 July 2017
Figure 4. Measured stratigraphic sections through glendonite-bearing horizons in the Deer Bay (DB1) and Christopher Formations (CH1 and CH2) exposed on Ellef Ringnes Island (locations are shown in Fig. 3 ). Mudstone is subdivided on the basis of texture (related to silt content) and weathering
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A) Stellate cluster of large glendonite pseudomorphs in the Wandrawandian Siltstone, Sydney Basin, New South Wales. B) "Pineapple" glendonite crystal array, Kola Peninsula. Scale in mm and cm.; C) Porous glendonite crystal array within concretion, Kola Peninsula. Note bivalve shell cemented within concretion. Scale in mm and cm.
Published: 01 November 2007
Figure 3 A) Stellate cluster of large glendonite pseudomorphs in the Wandrawandian Siltstone, Sydney Basin, New South Wales. B) "Pineapple" glendonite crystal array, Kola Peninsula. Scale in mm and cm.; C) Porous glendonite crystal array within concretion, Kola Peninsula. Note bivalve shell