Surface textures of quartz grains from Recent sedimentary environments along the Mediterranean Coast, Egypt

Abdalla, Mohamed A.

doi:10.1016/0899-5362(91)90100-d

Cited by 9 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…10), and this includes all kinds of tills that have been subglacially impacted. Available data from the surface microtextures support the interpretation that the present sand grains are from former fluvial, beach or continental shelf environments, but not from high-energy environments such as tectonic or subglacial settings (Abd-Alla, 1991, Prusak & Mazzullo, 1987Johnsson et al, 1991;Mahaney, 2002;Molén, 2014). Even if all History-2 fractures (F2, f2) are reinterpreted and assumed to be primary (F1, f1), the grains do not display any surface microtextures that are similar to those from grains transported by glaciers of any size (Molén, 2014), i.e., there are no fractures on grains that are irregularly abraded.…”

Section: Geađgefális and Viernjárgamentioning

confidence: 78%

The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general

Molén¹

2017

Geologos

View full text Add to dashboard Cite

Upper Precambrian diamictites in Varangerfjorden (northern Norway) have been examined for evidence of origin, whether glaciogenic, gravity flow or polygenetic. Studies of geomorphology, sedimentology and surface microtextures on quartz sand grains are integrated to provide multiple pieces of evidence for the geological agents responsible for the origin of the diamictites. The documented sedimentary and erosional structures, formerly interpreted in a glaciogenic context (e.g., diamict structure, pavements and striations) have been reanalysed. Field and laboratory data demonstrate that, contrary to conclusions reached in many earlier studies, the diamictites and adjacent deposits did not originate from glaciogenic processes. Evidence from macrostructures may occasionally be equivocal or can be interpreted as representing reworked, glacially derived material. Evidence from surface microtextures, from outcrops which are believed to exhibit the most unequivocal signs for glaciation, display no imprint at all of glaciogenic processes, and a multicyclical origin of the deposits can be demonstrated. The geological context implies (and no geological data contradict this) an origin by gravity flows, possibly in a submarine fan environment. This reinterpretation of the diamictites in northern Norway may imply that the palaeoclimatological hypothesis of a deep frozen earth during parts of the Neoproterozoic has to be revised.

show abstract

Section: Geađgefális and Viernjárgamentioning

confidence: 78%

The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general

Molén¹

2017

Geologos

View full text Add to dashboard Cite

show abstract

“…While there is some variability in the sediment size fraction between samples, the material used to model the human form and encase the mummies appears to have similar pedogenic characteristics and contains similar clay and salt morphologies. The abundance of well‐rounded and pitted sand grains exhibiting little fracturing suggests an aeolian history and the lower occurrence of silt‐ and clay‐sized particles suggests a regional origin and longer transport histories (Abd‐All 1991; Mahaney 1998, 2000). The clays are probably weathered from local parent material, which provides abundant chlorite and biotite (Bisdom et al .…”

Section: Discussionmentioning

confidence: 99%

Characterizing the Micromorphology of Sediments Associated With Chinchorro Mummification in Arica, Chile Using Sem and Eds

Hoesen

Arriaza

2011

Archaeometry

View full text Add to dashboard Cite

We use scanning electron microscopy (SEM) and energy‐dispersive spectroscopy (EDS) to analyse clay sediments used during the mummification process of Chinchorro mummies from northern Chile. The significance of this study is that no prior work has characterized the sediment used by the Chinchorro during mortuary preparation and this approach offers a necessary preliminary step towards identifying modern equivalents for the materials used by the Chinchorro. Understanding the unique characteristics of this material may also help understand why they are so well preserved and aid in the future curation of Chinchorro mummies.

show abstract

“…The increasing rate of evaporation and the existence of saline brine generally increase the pH which affects the quartz grains and influence the development of chemical features (Udayaganesan et al, 2011). Abd-Alla (1991) found the dominance of chemical features on the surface of quartz grains in the Mediterranean coast of sabkha deposits. The types and frequency of chemical features of quartz grains from sabkha deposits suggest that the grains have been subjected to high energy chemical dissolution.…”

Section: Coastal Sedimentsmentioning

confidence: 99%

Microtextures of Quartz Grain Surface from Recent Sedimentary Environments along Al-Khowkhah- Al-Mokha Coastal Area, Southern Red Sea, Yemen

Wasel¹

2012

مجلة جامعة الملك عبدالعزيز-علوم البحار

View full text Add to dashboard Cite

Scanning electron microscopy (SEM) analyses of quartz grains from Recent sedimentary environments such as beach, coastal duns,sabkha and wadi deposits in the Al-Khowkhah and Al-Mukha coastal area along southern Red Sea, Yemen, revealed variations in surface textures. Results of this study reveals the existence of distinguished surface features that reflect the effect of mechanical and chemical actions on the quartz grains. Quartz grains of beach, coastal dune and wadi deposits show significant abundance of both mechanical and chemical surface features developed during transportation of the grains in the subaqueous and aeolian environments, respectively. In contrast,quartz grains of sabkha are characterized by the dominance of chemical surface features. Among these chemical surface features, those originated from silica dissolution are considerably more numerous than those due to silica precipitation. Relative proportions of various surface features recorded on quartz grains from different environments indicate a considerable overlapping among the identified surface features in the examined quartz grains of coastal sediments and wadi deposits.

show abstract

Surface textures of quartz grains from Recent sedimentary environments along the Mediterranean Coast, Egypt

Cited by 9 publications

References 8 publications

The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general

The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general

Characterizing the Micromorphology of Sediments Associated With Chinchorro Mummification in Arica, Chile Using Sem and Eds

Microtextures of Quartz Grain Surface from Recent Sedimentary Environments along Al-Khowkhah- Al-Mokha Coastal Area, Southern Red Sea, Yemen

Contact Info

Product

Resources

About