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Fig. 7.

(A) Rounded quartz grain with bulbous edges showing numerous upturned plate...

Published: 12 February 2015
Fig. 7. (A) Rounded quartz grain with bulbous edges showing numerous upturned plates (arrows). (B) Near-spherical quartz grain with abundant upturned plates (arrows). Grain also shows small depressions attributed to grain collision during saltation. (C) Rounded elongate grain with bulbous edges
Journal Article

Submicroscopic Frosting on Eolian and Subaqueous Quartz Sand Grains

STANLEY V MARGOLIS, DAVID H KRINSLEY
Journal: GSA Bulletin
Published: 01 December 1971
GSA Bulletin (1971) 82 (12): 3395–3406.
DOI: https://doi.org/10.1130/0016-7606(1971)82[3395:SFOEAS]2.0.CO;2
... by simulating wind abrasion, is most pronounced on projections from the surface of the grains. Examination with a scanning electron microscope shows that this pattern consists of minute upturned plates of quartz that overlap each other and appear to be dipping in a direction possibly consistent with internal...
View PDF for article title, Submicroscopic Frosting on Eolian and Subaqueous Quartz Sand Grains
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Journal Article

Scanning electron microscope (SEM) microtextural analysis as a paleoclimate tool for fluvial deposits: A modern test

Curtis Smith, Gerilyn S. Soreghan, Tohru Ohta
Journal: GSA Bulletin
Published: 02 March 2018
GSA Bulletin (2018) 130 (7-8): 1256–1272.
DOI: https://doi.org/10.1130/B31692.1
... of upturned plates, interpreted to reflect the influence of high-stress eolian saltation on grains that subsequently underwent fluvial entrainment. Grains from proglacial systems exhibited a higher incidence of fracture faces, possibly attributable to the effects of both freeze-thaw weathering and glacial...
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View PDF for article title, Scanning electron microscope (SEM) microtextural analysis as a paleoclimate tool for fluvial deposits: A modern test
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Journal Article

Use of Quartz Microtextural Analysis To Assess Possible Proglacial Deposition For the Pennsylvanian–Permian Cutler Formation (Colorado, U.S.A.)

Leslie J. Keiser, Gerilyn S. Soreghan, Michal Kowalewski
Published: 01 November 2015
Journal of Sedimentary Research (2015) 85 (11): 1310–1322.
DOI: https://doi.org/10.2110/jsr.2015.81
..., straight grooves, deep troughs, and mechanically upturned plates have been found to be distinctive of glacial processes in particular. SEM analysis of quartz microtextures from the proximal (< 1 km) lacustrine, medial (1–3 km) lacustrine, and fluvial (> 3 km) facies of the Pennsylvanian–Permian...
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View PDF for article title, Use of Quartz Microtextural Analysis To Assess Possible Proglacial Deposition For the Pennsylvanian–Permian Cutler Formation (Colorado, U.S.A.)
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Journal Article

Early Cambrian coastal dunes at Vassbo, Sweden

BILL WALLIN
Journal: GSA Bulletin
Published: 01 November 1990
GSA Bulletin (1990) 102 (11): 1535–1543.
DOI: https://doi.org/10.1130/0016-7606(1990)102<1535:ECCDAV>2.3.CO;2
... deposits. Compared to the medium-grained facies, the fine-grained facies is characterized by negative skewness and better sorting. Additional evidence supporting an eolian origin of the upper facies is a wind-abraded pattern, characterized by "upturned plates," which have been observed on the quartz grain...
View PDF for article title, Early Cambrian coastal dunes at Vassbo, Sweden
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Journal Article

Grain-surface textures of late Wisconsinan sands from the Canadian Beaufort Shelf

Philip R. Hill, Odette C. Nadeau
Published: 01 December 1984
Journal of Sedimentary Research (1984) 54 (4): 1349–1357.
DOI: https://doi.org/10.1306/212F85D5-2B24-11D7-8648000102C1865D
... fractures; (b) angular grains with conchoidal fractures modified by solution/precipitation and edge abrasion; (c) irregularly shaped, rounded grains with mechanical v-marks and linear grooves; (d) well-rounded grains with dish-shaped concavities and upturned plates; and (e) type C and D grains with large...
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(a) Sub rounded quartz grain with straight steps, (b) Quartz grain showing flat faces, which indicates that the small sand grains have been broken mechanically, (c) Quartz grain with extremely irregular edges and conchoidal fractures, (d) Quartz grain showing irregular breakage blocks showing upturned plates, (e) Upturned plates, solution and precipitation, (f) Smoothness of the surface of quartz grain is due to chemical action giving rise to bulbous top (Surface of quartz grain has been smoothened by chemical action. Depressions marked by ellipses in the photo are the result of solution. Precipitation of silica in the form of globules giving rise to flowery structure).

(a) Sub rounded quartz grain with straight steps, (b) Quartz grain showi...

Published: 01 February 2020
blocks showing upturned plates, (e) Upturned plates, solution and precipitation, (f) Smoothness of the surface of quartz grain is due to chemical action giving rise to bulbous top (Surface of quartz grain has been smoothened by chemical action. Depressions marked by ellipses in the photo
Image
Scanning electron microscopy images of microtextures on quartz sand grains from the Fountain Formation. A, Angular quartz grain displaying high-relief, subparallel linear fractures (lf) and a deep trough (dt). B, Straight grooves (sg) on a fracture face. C, Straight grooves (sg) and linear steps (ls). A euhedral quartz overgrowth (ov) has formed at the terminus of the grooves. D, Irregularly shaped grain displaying high-relief and arc-shaped steps (as). The grain surface is coated with turtle-skin silica, local clay minerals, and a mica grain. E, Fractured grain surface covered with turtle-skin silica displaying remnant crescentic gouges (cg). F, Mechanically upturned plate (mup) on grain surface with local pockets of quartz precipitation (qp) on upturned plate.

Scanning electron microscopy images of microtextures on quartz sand grains ...

Published: 14 March 2014
with turtle-skin silica displaying remnant crescentic gouges (cg). F , Mechanically upturned plate (mup) on grain surface with local pockets of quartz precipitation (qp) on upturned plate.
Image
A: Photo of sandstone outcrop 39.9115, showing meter-scale cross-bedding (dashed white lines), color, and contacts (solid lines) typical of eolian strata. B: Scanning electron microscopy photo of a typical grain from eolian strata, showing pitted surface with irregular depressions and upturned plates.

A: Photo of sandstone outcrop 39.9115, showing meter-scale cross-bedding (d...

Published: 11 September 2018
and upturned plates.
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Scanning electron microscope micrographs of grains from Ocean Drilling Program Site 696. (A) Grain type A with an angular outline, high relief, large conchoidal fracture, subparallel linear fracture, straight steps, fracture face, straight groove, and solution pits. (B) Grain type A with a subangular outline, medium relief, large conchoidal fracture, subparallel linear fracture, and adhering particles. (C) Grain type B with a subangular outline, medium relief, dissolution weathering, and adhering particles. (D) Grain type B with subangular outline, medium relief, dissolution weathering, adhering particles, and granular precipitation. (E) Grain type C with a subrounded outline, medium relief, and upturned plates. (F) Grain type D with an angular outline, low relief, euhedral overgrowth, and dissolution etching. (G) Grain type E with a rounded outline, medium relief, dissolution weathering, and edge abrasion. (H) Grain type E with a subrounded outline, medium relief, irregular dish-shaped depressions, impact craters, solution pits, granular precipitation, and a bulbous feature. AP—adhering particles; DW—dissolution weathering; GP—granular precipitation; UP—upturned plates; EU—euhedral overgrowth; DE—dissolution etching; EA—edge abrasion; IC—impact craters; SP—solution pits; BF—bulbous feature; ID—irregular dish-shaped depression; SS—straight steps; LCF—large conchoidal fracture (&gt;10 µm); SLF—subparallel linear fracture; FF—fracture face; SG—straight groove.

Scanning electron microscope micrographs of grains from Ocean Drilling Prog...

Published: 14 May 2024
, adhering particles, and granular precipitation. (E) Grain type C with a subrounded outline, medium relief, and upturned plates. (F) Grain type D with an angular outline, low relief, euhedral overgrowth, and dissolution etching. (G) Grain type E with a rounded outline, medium relief, dissolution weathering
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Scanning electron microscope images show quartz-grain surfaces of aeolian sandstones from the Baiyin-Jingyuan Basin. (A) Rounded outline and low relief of quartz grain surfaces. (B) Crescentic percussion marks (white arrows) on the surface. (C) Low relief and solution pits (white arrows) on the surface. (D) Upturned plates (black arrows) and crescentic percussion marks (white arrows) on the surface.

Scanning electron microscope images show quartz-grain surfaces of aeolian s...

Published: 06 April 2023
) on the surface. (D) Upturned plates (black arrows) and crescentic percussion marks (white arrows) on the surface.
Image
SEM images of a variety of microtextures from quartz sand grains from the Fountain Formation. A) Well-rounded quartz grain recovered from marine shoreface facies. This grain displays numerous randomly oriented v-shaped cracks (vc; only a few highlighted for clarity) and is coated with turtle-skin silica and local authigenic clay minerals. B) Angular quartz grain displaying high-relief, subparallel linear fractures (lf) and a deep trough (dt). C) Straight grooves (sg) on a fracture face. D) Straight grooves (sg) and linear steps (ls). A euhedral quartz overgrowth (ov) has formed at the terminus of the grooves. E) Irregularly shaped grain displaying high-relief and arc-shaped steps (as). Grain surface is coated with turtle-skin silica, local clay minerals, and mica grain. F) Fractured grain surface covered with turtle-skin silica displaying remnant crescentic gouges (cg). G) Fracture face (ff) on grain surface shows evidence for edge rounding (er) fracturing including v-shaped cracks (vc). H) Mechanically upturned plate (mup) on grain surface with local pockets of quartz precipitation (qp) on upturned plate. I) Well-rounded grain recovered from marine shoreface facies showing randomly oriented v-shaped cracks (vc).

SEM images of a variety of microtextures from quartz sand grains from the F...

Published: 01 July 2010
) Fracture face (ff) on grain surface shows evidence for edge rounding (er) fracturing including v-shaped cracks (vc). H) Mechanically upturned plate (mup) on grain surface with local pockets of quartz precipitation (qp) on upturned plate. I) Well-rounded grain recovered from marine shoreface facies
Image
Abundances of V-shaped cracks (vc) and precipitation features (pf), upturned plates (up), and fracture-striae, consisting of fracture faces (ff), subparallel linear fractures (slf), curved grooves (cg), straight grooves (sg), and deep troughs (dt). Moraine samples are illustrated with filled symbols. The 95% confidence regions of the population mean (solid line) were drawn following the method described in Weltje (2002) and Thió-Henestrosa and Martín-Fernández (2005). NO—Norway, PE—Peru, CA—California, and PR—Puerto Rico.

Abundances of V-shaped cracks (vc) and precipitation features (pf), upturne...

Published: 02 March 2018
Figure 8. Abundances of V-shaped cracks (vc) and precipitation features (pf), upturned plates (up), and fracture-striae, consisting of fracture faces (ff), subparallel linear fractures (slf), curved grooves (cg), straight grooves (sg), and deep troughs (dt). Moraine samples are illustrated
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SEM images of selected quartz grains from the medial facies in the Cutler Formation. A) A straight groove (sg) is shown covered in precipitation features (pf) on a slightly rounded quartz grain. B) Mechanically upturned plate (mup), adhering particles (ap), and linear steps (ls) are present on this quartz grain surface. C) A pronounced curved groove (cg) is displayed on this quartz grain as well as a crescentic gouge (crg), subparallel linear fractures (sf). Edge rounding (er) is present as well. See Table 1 for explanation of microtextures.

SEM images of selected quartz grains from the medial facies in the Cutler F...

Published: 01 November 2015
Fig. 7.— SEM images of selected quartz grains from the medial facies in the Cutler Formation. A) A straight groove (sg) is shown covered in precipitation features (pf) on a slightly rounded quartz grain. B) Mechanically upturned plate (mup), adhering particles (ap), and linear steps (ls
Image
Fig. 8.

(A) Rounded grain (originally triangular) with bulbous edges. Grain has its...

Published: 12 February 2015
of silica. (C) Quartz grain with irregular depressions (arrows at top) and abundant upturned plates (bottom right). (D) Quartz grain with triangular depression. This depression could be related to grain collisions in an eolian environment or during violent collision in subaqueous transport, which creates V
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Typical sedimentary and grain surface structures in association I of the Sikouzi section. a, Graded bedding lamination. b, Small-scale deformation structures. c, Cross-cutting relationships in meter scale, showing the first- and second-order bounding surfaces. d, Cross-cutting relationships in tens of centimeters scale, showing the second- and third-order bounding surfaces drawn in dashed white lines. e, Pool deposits (brick red) hosted in the eolian sequences. f, Scanning electron microscopy (SEM) image showing the dish-shaped depressions. g, SEM image showing the upturned plates.

Typical sedimentary and grain surface structures in association I of the Si...

Published: 09 June 2015
relationships in tens of centimeters scale, showing the second- and third-order bounding surfaces drawn in dashed white lines. e , Pool deposits (brick red) hosted in the eolian sequences. f , Scanning electron microscopy (SEM) image showing the dish-shaped depressions. g , SEM image showing the upturned
Image
A, Subround quartz from 831-Cz2 with pronounced bulbous microfeatures, V-shaped percussion cracks (lower and upper right facets), minor troughs, striae, adhering particles, conchoidal and subparallel fractures, mostly lightly covered with salts and very thin Fe coats in places. Considerably thick accumulations of salts, mainly gypsum to left. B, Subangular orthoclase grain with fewer adhering particles. Minor troughs and striae on the right facet, with scattered V-shaped percussion cracks on the upper surface along with minor upturned plate. The upper outer rim appears with discontinuous salt coatings.

A , Subround quartz from 831-Cz2 with pronounced bulbous microfeatures, V-s...

Published: 18 February 2015
. Considerably thick accumulations of salts, mainly gypsum to left. B , Subangular orthoclase grain with fewer adhering particles. Minor troughs and striae on the right facet, with scattered V-shaped percussion cracks on the upper surface along with minor upturned plate. The upper outer rim appears
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Relative abundances of polygenetic, high-stress and percussion fractures (following definition of Sweet and Soreghan 2010a) on quartz grains from the proximal lacustrine, medial lacustrine, and fluvial facies associations of the Cutler Formation. High-stress fractures are defined as straight and curved grooves, deep troughs, and mechanically upturned plates. V-shaped cracks, edge rounding, and dissolution etching are considered to be percussion fractures. Polygenetic fractures are fracture faces, subparallel linear fractures, conchoidal fracture, arc-shaped steps, linear steps, and breakage blocks. High-stress fractures are more abundant in the proximal lacustrine facies whereas percussion fractures are more abundant in the fluvial facies.

Relative abundances of polygenetic, high-stress and percussion fractures (f...

Published: 01 November 2015
as straight and curved grooves, deep troughs, and mechanically upturned plates. V-shaped cracks, edge rounding, and dissolution etching are considered to be percussion fractures. Polygenetic fractures are fracture faces, subparallel linear fractures, conchoidal fracture, arc-shaped steps, linear steps
Image
SEM images of selected quartz grains from the proximal lacustrine facies in the Cutler Formation. A) Angular quartz grain displays numerous high-stress fractures such as a straight groove (sg), crescentic gouge (crg), and mechanically upturned plate (mup). Subparallel linear fractures (sf), conchoidal fracture (cf), adhering particles (ap), and precipitation features (pf) are also present. B) Angular quartz grain displaying a deep trough (dt) and straight groove (sg) as well as subparallel linear fractures (sf), conchoidal fractures (cf), and precipitation features (pf). C) Quartz grain with abundant precipitation superimposed on a curved groove (cg) and deep troughs (dt). See Table 1 for explanation of microtextures.

SEM images of selected quartz grains from the proximal lacustrine facies in...

Published: 01 November 2015
Fig. 6.— SEM images of selected quartz grains from the proximal lacustrine facies in the Cutler Formation. A) Angular quartz grain displays numerous high-stress fractures such as a straight groove (sg), crescentic gouge (crg), and mechanically upturned plate (mup). Subparallel linear fractures
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Selected textures documented in this study. (A) Grid layout of individual grains on a scanning electron microscope (SEM) stub. (B) Grain surface displaying a V-shaped crack (vc) and triangular dissolution etching (de). (C) Straight groove (sg) and a curved groove (cg). (D) Grain showing arc-shaped steps (as), and nonlinear step features. (E) Deep trough (dt) on an angular grain. (F) Grain showing heavy precipitation features (pf), with arc-shaped steps (as) and linear steps (ls). (G) Grain showing subparallel linear fractions (slf). (H) Close-up view of triangular dissolution etching (de) and conchoidal fractures (cf; polygenetic fractures characterized by a curved smooth appearance) on the bottom edge. Note that all dissolution etch pits have the same orientation. (I) Grain surface showing upturned plate (up).

Selected textures documented in this study. (A) Grid layout of individual g...

Published: 02 March 2018
(de) and conchoidal fractures (cf; polygenetic fractures characterized by a curved smooth appearance) on the bottom edge. Note that all dissolution etch pits have the same orientation. (I) Grain surface showing upturned plate (up).