A discussion on the structure and evolution of the Red Sea and the nature of the Red Sea, Gulf of Aden and Ethiopia rift junction - Interpretation of satellite photographs of the Red Sea and Gulf of Aden

1970 ◽  
Vol 267 (1181) ◽  
pp. 23-40 ◽  
Keyword(s):  
Red Sea ◽  
Large Scale ◽  
Lateral Displacement ◽  
Shear Zones ◽  
Poor Correlation ◽  
Gulf Of Aden ◽  
Alluvial Deposits ◽  
Total Movement ◽  
Southern Arabia ◽  
Northern Red Sea

Geological structures observed in Gemini and Apollo colour photographs suggest that large-scale translational movements could have taken place in the Red Sea and Gulf of Aden. In the northern Red Sea the apparent displacement of two pairs of shear zones and three pairs of serpentinite belts is consistent with a movement of Arabia towards the NNE of some 150 km. In the southern part of the Red Sea evidence of displacement is derived from correlation of Precambrian trend-lines, particularly at points where there is an abrupt change in the regional grain; at Ras Kasr-Al Lith (latitudes 18° N and 20° N) the total movement could be 225 km. Across the Gulf of Aden observations are in general agreement with the pre-Miocene fit proposed by Laughton (1965). Study of satellite photographs provide the following additional evidence: (1) The continuity of the Hadramawt folds (southern Arabia) in the Somali Plateau; the southern Hadramawt arch appears to be extended in the northern Somali arch. (2) Pre-drift correlation of several fault zones of WNW-ESE trend across the Gulf. The NE-SW faults, on the other hand, show poor correlation across the Gulf and appear to be related to fault lineaments within the Gulf of Aden. Across the Strait of Bab El Mandeb geological and morphological similarities in the distribution of Quaternary sediments, volcanic fields, intervening alluvial deposits, fault and drainage lineaments suggest a left-lateral displacement of Arabia some 40 km to the NNE since the Plio-Pleistocene. Such a movement could have resulted in the final opening of the Bab El Mandeb Strait.

A discussion on the structure and evolution of the Red Sea and the nature of the Red Sea, Gulf of Aden and Ethiopia rift junction - Short discussion contributions

1970 ◽  
Vol 267 (1181) ◽  
pp. 413-414 ◽  
Keyword(s):  
Red Sea ◽  
Gulf Of Suez ◽  
Gulf Of Aden ◽  
Short Discussion ◽  
The Hague ◽  
Sea Area ◽  
Northern Red Sea

H. M. E. Schürmann ( The Hague ). I would like to remark that epeirogenetic movements in the Precambrian of the Gulf of Suez and the northern Red Sea area have been proven. They are of Precambrian age as they have been observed underneath the Hammamat (youngest Precambrian) transgression. In Palaeozoic times several marine ingressions took place and similar ingressions occurred in Permian, Jurassic and Cretaceous times, indicating continued subsidence. The big clysmic taphrogeny took place in young Tertiary times.

scholarly journals Large-Scale Mode Impacts on the Sea Level over the Red Sea and Gulf of Aden

2019 ◽  
Vol 11 (19) ◽  
pp. 2224 ◽  
Author(s):  
Kamal A. Alawad ◽  
Abdullah M. Al-Subhi ◽  
Mohammed A. Alsaafani ◽  
Turki M. Alraddadi ◽  
Monica Ionita ◽  
...  
Keyword(s):  
Sea Level ◽  
Red Sea ◽  
El Niño ◽  
Large Scale ◽  
El Nino ◽  
Southern Oscillation ◽  
Positive Phase ◽  
El Nino Southern Oscillation ◽  
Gulf Of Aden ◽  
The Impact

Falling between seasonal cycle variability and the impact of local drivers, the sea level in the Red Sea and Gulf of Aden has been given less consideration, especially with large-scale modes. With multiple decades of satellite altimetry observations combined with good spatial resolution, the time has come for diagnosis of the impact of large-scale modes on the sea level in those important semi-enclosed basins. While the annual cycle of sea level appeared as a dominant cycle using spectral analysis, the semi-annual one was also found, although much weaker. The first empirical orthogonal function mode explained, on average, about 65% of the total variance throughout the seasons, while their principal components clearly captured the strong La Niña event (1999–2001) in all seasons. The sea level showed a strong positive relation with positive phase El Niño Southern Oscillation in all seasons and a strong negative relation with East Atlantic/West Russia during winter and spring over the study period (1993–2017). We show that the unusually stronger easterly winds that are displaced north of the equator generate an upwelling area near the Sumatra coast and they drive both warm surface and deep-water masses toward the West Indian Ocean and Arabian Sea, rising sea level over the Red Sea and Gulf of Aden. This process could explain the increase of sea level in the basin during the positive phase of El Niño Southern Oscillation events.

A discussion on the structure and evolution of the Red Sea and the nature of the Red Sea, Gulf of Aden and Ethiopia rift junction - General Discussion - Introduction to the general discussion

1970 ◽  
Vol 267 (1181) ◽  
pp. 397-398
Keyword(s):  
Red Sea ◽  
Large Scale ◽  
Dead Sea ◽  
Crystalline Rocks ◽  
Petroleum Exploration ◽  
Gulf Of Aden ◽  
Igneous Intrusion ◽  
Fundamental Interest ◽  
The Dead ◽  
Surface Geology

The meeting has promoted a valuable exchange of ideas between field geologists, geologists engaged in petroleum exploration in and around the Red Sea, and geophysicists who have undertaken land, airborne and marine surveys. The results are of fundamental interest in several fields. The ancient crystalline rocks, discussed by Brown and Beydoun, revealed little to suggest a control of the Red Sea geosuture by Precambrian structures. The old eugeosynclinal trough in Arabia perhaps trends N 30° W, but Brown had been unwilling to assign a direction to the postulated miogeosynclinal trough. The early sediments had been extensively annealed by metamorphism and by igneous intrusion on a large scale. It did not appear that an obvious case for the location of either the Red Sea or the Gulf of Aden along a pre-existing line of crustal weakness could be made out from the surface geology, though the case of the Dead Sea rift may be different.

scholarly journals Atmospheric Forcing of the Winter Air–Sea Heat Fluxes over the Northern Red Sea

2013 ◽  
Vol 26 (5) ◽  
pp. 1685-1701 ◽  
Author(s):  
Vassilis P. Papadopoulos ◽  
Yasser Abualnaja ◽  
Simon A. Josey ◽  
Amy Bower ◽  
Dionysios E. Raitsos ◽  
...  
Keyword(s):  
Heat Flux ◽  
Heat Loss ◽  
Atmospheric Circulation ◽  
Red Sea ◽  
Large Scale ◽  
Turbulent Flux ◽  
Eastern Mediterranean ◽  
Surface Heat ◽  
Heat Fluxes ◽  
Northern Red Sea

Abstract The influence of the atmospheric circulation on the winter air–sea heat fluxes over the northern Red Sea is investigated during the period 1985–2011. The analysis based on daily heat flux values reveals that most of the net surface heat exchange variability depends on the behavior of the turbulent components of the surface flux (the sum of the latent and sensible heat). The large-scale composite sea level pressure (SLP) maps corresponding to turbulent flux minima and maxima show distinct atmospheric circulation patterns associated with each case. In general, extreme heat loss (with turbulent flux lower than −400 W m−2) over the northern Red Sea is observed when anticyclonic conditions prevail over an area extending from the Mediterranean Sea to eastern Asia along with a recession of the equatorial African lows system. Subcenters of high pressure associated with this pattern generate the required steep SLP gradient that enhances the wind magnitude and transfers cold and dry air masses from higher latitudes. Conversely, turbulent flux maxima (heat loss minimization with values from −100 to −50 W m−2) are associated with prevailing low pressures over the eastern Mediterranean and an extended equatorial African low that reaches the southern part of the Red Sea. In this case, a smooth SLP field over the northern Red Sea results in weak winds over the area that in turn reduce the surface heat loss. At the same time, southerlies blowing along the main axis of the Red Sea transfer warm and humid air northward, favoring heat flux maxima.

Revision of the congrogadid Haliophis (Pisces: Perciformes), with the description of a new species from Indonesia, and comments on the endemic fish fauna of the northern Red Sea

1985 ◽  
Vol 63 (2) ◽  
pp. 209-217 ◽  
Author(s):  
Richard Winterbottom
Keyword(s):  
New Species ◽  
Indian Ocean ◽  
Red Sea ◽  
Fish Fauna ◽  
Western Indian Ocean ◽  
Gulf Of Aden ◽  
Form Part ◽  
Ocean Region ◽  
Northern Red Sea ◽  
A New Species

The genus Haliophis presently consists of two species, H. guttatus (Forsskål, 1755), and a new species from Bali, Indonesia. Descriptions, diagnoses, and a key are provided for these taxa. A step cline occurs in H. guttatus, which ranges from 15° S to 30° N in the western Indian Ocean and Red Sea. Populations from 27 to 30°N differ most from those in the southern Red Sea and Gulf of Aden, but less so from those south of the equator. The step occurs between 20 and 27° N, an area from which no specimens were located, and is congruent with the distributions of at least four other taxa of fishes as well as with several populational differences in other species. This indicates that these distributional patterns may form part of a generalized track, rather than being the result of ecophenotypic effects. In the Red Sea – northern Indian Ocean region, the most common distribution of endemic fishes includes both the Red Sea and the Gulf of Aden. This pattern was not apparent in populations of H. guttatus.

A discussion on the structure and evolution of the Red Sea and the nature of the Red Sea, Gulf of Aden and Ethiopia rift junction - Southern Arabia and northern Somalia: Comparative geology

1970 ◽  
Vol 267 (1181) ◽  
pp. 267-292 ◽  
Keyword(s):  
Red Sea ◽  
Gulf Of Aden ◽  
Clockwise Rotation ◽  
The West ◽  
Geological Evidence ◽  
Positive Correlation ◽  
Geological Features ◽  
Single Block ◽  
Southern Arabia ◽  
Two Sides

Detailed geological compilation maps for the two sides of the Gulf of Aden from various published and unpublished sources were originally prepared on 1:500 000 scale and later reduced to 1:1 000 000 scale (figures 3 and 4, in accompanying wallet). These were reconstructed to postulated pre-separation positions along the 100- and 500-fathom (183 and 914 m) bathymetric contours to give acceptably close fits for most of the area west of Alula-Ras Fartaq, leaving water gaps of 25 40 and 50-80 km respectively between the two shores. The 500-fathom fit shows several striking similarities and apparent continuity of geological features between the two sides, but detailed correlation reveals a number of offsets and mismatches. The 100- fathom fit gives a considerably improved overall correlation with continuity of structural and facies belts across the intervening water, though detailed comparisons do not bring out many correlations that give direct and positive geological support for separation and these are mainly structural rather than stratigraphic. This paucity in positive correlation may be partly accounted for by the width of the remaining water gap and by the differing geomorphology and degree of erosion between the eastern portion of the two sides. Although the reconstructions reveal appreciable circumstantial support for separation and no major geological evidence against it, an overlap results in the extreme west of the map area (appreciably greater for the 100-fathom fit) where Basement and Mesozoic rocks on either side are superimposed on one another; a considerably greater overlap occurs outside the map area to the west between similar rocks of Yemen and the Danakil alps of Ethiopia. If Arabia moved as a single block in a northeast direction and with counter clockwise rotation away from the Somali (and Nubian) block, reconstructing it to its preseparation position requires the satisfactory resolution of this overlap before it can be acceptable; a separate northeast movement of the Socotra shelf is moreover required to accommodate a fit with the reconstructed Dhufar-Kuria portion of the Arabian block.

scholarly journals Meso- and microscale sea-ice motion in the East Siberian Sea as determined from ERS-1 SAR Data

1999 ◽  
Vol 45 (150) ◽  
pp. 370-383 ◽  
Author(s):  
Kim Morris ◽  
Shusun Li ◽  
Martin Jeffries
Keyword(s):  
Time Series ◽  
Sea Ice ◽  
Large Scale ◽  
Vector Fields ◽  
Lateral Displacement ◽  
Motion Vector ◽  
Sar Interferometry ◽  
East Siberian Sea ◽  
Pack Ice ◽  
Sar Data

Abstract Synthetic aperture radar- (SAR-)derived ice-motion vectors and SAR interferometry were used to study the sea-ice conditions in the region between the coast and 75° N (~ 560 km) in the East Siberian Sea in the vicinity of the Kolyma River. ERS-1 SAR data were acquired between 24 December 1993 and 30 March 1994 during the 3 day repeat Ice Phase of the satellite. The time series of the ice-motion vector fields revealed rapid (3 day) changes in the direction and displacement of the pack ice. Longer-term (≥ 1 month) trends also emerged which were related to changes in large-scale atmospheric circulation. On the basis of this time series, three sea-ice zones were identified: the near-shore, stationary-ice zone; a transitional-ice zone;and the pack-ice zone. Three 3 day interval and one 9 day interval interferometric sets (amplitude, correlation and phase diagrams) were generated for the end of December, the begining of February and mid-March. They revealed that the stationary-ice zone adjacent to the coast is in constant motion, primarily by lateral displacement, bending, tilting and rotation induced by atmospheric/oceanic forcing. The interferogram patterns change through time as the sea ice becomes thicker and a network of cracks becomes established in the ice cover. It was found that the major features in the interferograms were spatially correlated with sea-ice deformation features (cracks and ridges) and major discontinuities in ice thickness.

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