Aeromagnetic Data Investigation of Al-Shamiyya Area, North East of Makkah Quadrangle, Saudi Arabia

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Kalsbeek, F., & Skjernaa, L. (1999). The Archaean Atâ intrusive complex (Atâ tonalite), north-east Disko Bugt, West Greenland. Geology of Greenland Survey Bulletin, 181, 103-112. https://doi.org/10.34194/ggub.v181.5118 _______________ The 2800 Ma Atâ intrusive complex (elsewhere referred to as ‘Atâ granite’ or ‘Atâ tonalite’), which occupies an area of c. 400 km2 in the area north-east of Disko Bugt, was emplaced into grey migmatitic gneisses and supracrustal rocks. At its southern border the Atâ complex is cut by younger granites. The complex is divided by a belt of supracrustal rocks into a western, mainly tonalitic part, and an eastern part consisting mainly of granodiorite and trondhjemite. The ‘eastern complex’ is a classical pluton. It is little deformed in its central part, displaying well-preserved igneous layering and local orbicular textures. Near its intrusive contact with the overlying supracrustal rocks the rocks become foliated, with foliation parallel to the contact. The Atâ intrusive complex has escaped much of the later Archaean and early Proterozoic deformation and metamorphism that characterises the gneisses to the north and to the south; it belongs to the best-preserved Archaean tonalite-trondhjemite-granodiorite intrusions in Greenland.

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Stratigraphy, structure and geochemistry of Archaean supracrustal rocks from Oqaatsut and Naajaat Qaqqaat, north-east Disko Bugt, West Greenland

Geological Survey of Denmark and Greenland Bulletin ◽

10.34194/ggub.v181.5114 ◽

1999 ◽

pp. 65-78

Author(s):

Henrik Rasmussen ◽

Lars Frimodt Pedersen

Keyword(s):

Tectonic Setting ◽

Trace Element Geochemistry ◽

Element Geochemistry ◽

West Greenland ◽

North West ◽

North East ◽

Metavolcanic Rocks ◽

Arc Setting ◽

Area North ◽

Back Arc

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Rasmussen, H., & Frimodt Pedersen, L. (1999). Stratigraphy, structure and geochemistry of Archaean supracrustal rocks from Oqaatsut and Naajaat Qaqqaat, north-east Disko Bugt, West Greenland. Geology of Greenland Survey Bulletin, 181, 65-78. https://doi.org/10.34194/ggub.v181.5114 _______________ Two Archaean supracrustal sequences in the area north-east of Disko Bugt, c. 1950 and c. 800 m in thickness, are dominated by pelitic and semipelitic mica schists, interlayered with basic metavolcanic rocks. A polymict conglomerate occurs locally at the base of one of the sequences. One of the supracrustal sequences has undergone four phases of deformation; the other three phases. In both sequences an early phase, now represented by isoclinal folds, was followed by north-west-directed thrusting. A penetrative deformation represented by upright to steeply inclined folds is only recognised in one of the sequences. Steep, brittle N–S and NW–SE striking faults transect all rock units including late stage dolerites and lamprophyres. Investigation of major- and trace-element geochemistry based on discrimination diagrams for tectonic setting suggests that both metasediments and metavolcanic rocks were deposited in an environment similar to a modern back-arc setting.

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Crustal structure of the northern Harrat Rahat volcanic field (Saudi Arabia) from gravity and aeromagnetic data

Tectonophysics ◽

10.1016/j.tecto.2018.11.005 ◽

2019 ◽

Vol 750 ◽

pp. 9-21 ◽

Cited By ~ 3

Author(s):

V.E. Langenheim ◽

B.T. Ritzinger ◽

Hani Zahran ◽

Adel Shareef ◽

Maher Al-dahri

Keyword(s):

Saudi Arabia ◽

Crustal Structure ◽

Volcanic Field ◽

Aeromagnetic Data ◽

Harrat Rahat

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Pre-Nagssugtoqidian crustal evolution in West Greenland: geology, geochemistry and deformation of supracrustal and granitic rocks north-east of Kangaatsiaq

Geological Survey of Denmark and Greenland Bulletin ◽

10.34194/geusb.v11.4915 ◽

2006 ◽

Vol 11 ◽

pp. 33-52

Author(s):

Jean-François Moyen ◽

Gordon R. Watt

Keyword(s):

Sedimentary Basin ◽

Granulite Facies ◽

Great Circle ◽

Granitic Rocks ◽

Early Event ◽

Porphyritic Granite ◽

The Core ◽

North East ◽

Greenstone Belts ◽

Area North

The area north-east of Kangaatsiaq features polyphase grey orthogneisses, supracrustal rocks and Kangaatsiaq granite exposed within a WSW–ENE-trending synform. The supracrustal rocks are comprised of garnet-bearing metapelites, layered amphibolites and layered, likewise grey biotite paragneisses. Their association and geochemical compositions are consistent with a metamorphosed volcano-sedimentary basin (containing both tholeiitic and calc-alkali lavas) and is similar to other Archaean greenstone belts. The Kangaatsiaq granite forms a 15 × 3 km flat, subconcordant body of deformed, pink, porphyritic granite occupying the core of the supracrustal synform, and is demonstrably intrusive into the amphibolites. The granite displays a pronounced linear fabric (L or L > S). The post-granite deformation developed under lower amphibolite facies conditions (400 ± 50°C), and is characterised by a regular, NE–SW-trending subhorizontal lineation and an associated irregular foliation, whose poles define a great circle; together they are indicative of highly constrictional strain. The existence of a pre-granite event is attested by early isoclinal folds and a foliation within the amphibolites that is not present in the granite, and by the fact that the granite cuts earlier structures in the supracrustal rocks. This early event, preserved only in quartz-free lithologies, resulted in high-temperature fabrics being developed under upper amphibolite to granulite facies conditions.

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Utilization of Smartphones in Learning

International Educational Research ◽

10.30560/ier.v1n1p51 ◽

2018 ◽

Vol 1 (1) ◽

pp. p51

Author(s):

Ali Alkhalifa ◽

Yazan Alghazo

Keyword(s):

College Students ◽

Saudi Arabia ◽

Mixed Methods ◽

Mixed Methods Approach ◽

Data Investigation

The purpose of this research is to find out how college students in Saudi Arabia utilize their smartphones in their learning and to find out the effect of its use in their learning and investigate ways that are more effective for such use. In order to achieve this goal, a researcher developed questionnaire was distributed to 93 college students. The study utilized a mixed-methods approach in collecting data. Investigation Results are analyzed and demonstrated with charts, followed by a discussion of the main findings.

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Offshore Wind Power Assessment on the East Coast of Saudi Arabia

Wind Engineering ◽

10.1260/030952405775992643 ◽

2005 ◽

Vol 29 (5) ◽

pp. 409-419 ◽

Cited By ~ 7

Author(s):

Shafiqur Rehman

Keyword(s):

Saudi Arabia ◽

Wind Speed ◽

Ghg Emissions ◽

Resource Assessment ◽

Offshore Wind ◽

Energy Yield ◽

North West ◽

North East ◽

Prevailing Wind Direction ◽

Wind Resource

This paper, to the best of author's knowledge, presents the first wind resource assessment for offshore-wind energy off the mainland coasts of Saudi Arabia, despite the onshore wind resource being known. The study utilized wind speed data from, in effect, an offshore meteorological station to study the annual and seasonal variation of wind speed, wind speed frequency distribution, energy yield and consequent opportunity for reduction in green house gases (GHG) emissions. These results were compared with contemporaneous data from a mainland location ∼ 10 km inland at the same longitude Energy yields were calculated using HOMER and RetScreen models. The annual mean wind measured at Abu Ali Island, the offshore location, was 5.43 m/s. This is larger than the 4.9 m/s measured over the same period at Abu Kharuf, the nearby inland location. Larger wind speeds were found in winter months than in summer months at both locations. At Abu Ali Island, the power of the wind could be extracted for 75% of the time at hub-height of 60 meters using modern wind machines of cut-in-speed 4 m/s, in comparison with 60% of time at Abu Kharuf. The prevailing wind direction was found to be North (N), North West (NNW) and North East (NNE).

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