We present a novel numerical method based on domain decomposition for the simulation of 3D geophysical marine controlled source electromagnetic (CSEM) measurements. Parts of the computational domain where it is reasonable to represent geoelectric properties in 2D, are discretized combining 2D mixed finite elements (FE) and Fourier expansion. The remaining part is discretized utilizing standard 3D FE methods. The method delivers high-accuracy simulations of marine CSEM problems with arbitrary 3D geometries while it considerably reduces the computational complexity of full 3D FE simulations for typical marine CSEM problems. For the particular scenarios considered in this work, the total CPU time required by the novel method is reduced approximately by a factor of five with respect to that needed by full 3D FE formulations.

We examined vegetation composition and its relation to environmen­ tal variables in the Sidlum area along the mediterranean coastal land of Egypt. The study area lies between 25° 09'-25° 35'E and 31° 32'­ 31° 15' N (about 1700knr), and extendi-.!or about 49 km between Buqbuq and Sallum on the egyptian-libyan frontier. It ii' included in the semi-desert vegetation zone with an attenuated desert climate. An analysis of vegetation along environmental gradients that prevail in the study area using the relative importance values of 55 perennials in 53 stands, fOllowed by multivariate data analysis was presented. Altogether, 1// i!JI'cie.' (75 perennials aw!3(, (';/ill,.:l,-) be!riJIo!I/CJ to 92 genera and 34 families of the flowering plancs were recorded~ Asreraceae, Fabaceae, Chenopodiaceae, Poaceae, Brassicaceae, Caryophyllaceae, Liliaceae and Zygophyllaceae were the largest families, and constitute more than 64 % of the total recorded species. Therophytes and chamaephytes were the most frequent, denoting a
typical desert lifeform spectrum. Phytochorological analyi'is revealed that 45.2 % of the studied species were uniregional, of which 23 % being native to the saharo-arabian chorotype. It also showed the decrease in the numbers of the Mediterranean species and increase of the saharo-arabian species along N-S direction fOrm the see-shore inwards till the Diffa Plateau. Classification of the vegetation was analysed using TWINSPAN technique resulted in the recognition of five vegetation groups, each of definite floristic composition and environmental characteristics, and could be linked to a specific habitat. Haloxylon salicornicum occupied the fOot of the Diffa Plateau, Haloxylon salicornicum- Thymelaea hirsura characterised the sand plains, Thymelaea hirsura-Anabasis articulara inhabited the non-saline depressions, Haloxylon salicornicum-Auiplex por­ rulacoides characterised the saline depressions and Salsola reuan­ dra-Limoniasrrum monoperalum on the coastal salt marshes. Ordination techniques as DCA and CCA were used to examine the relationship between the vegetation and the studied environmental parameters: electric conductivity (EC), pH, calcium carbonate, mois­ ture content, organic matter, silt, clay, K., Mg;+ and altitude. CCA axis 1 showed significant correlation with clay, moisture content, pH, Ee, K', and altitude, while CCA axis 2 was clearly related to pH, Mg;' and altitude. Species richness was correlated with Mg;., while Shannon index was correlated with Na+ and Mg;+.

We examined vegetation composition and its relation to environmen­ tal variables in the Sidlum area along the mediterranean coastal land of Egypt. The study area lies between 25° 09'-25° 35'E and 31° 32'­ 31° 15' N (about 1700knr), and extendi-.!or about 49 km between Buqbuq and Sallum on the egyptian-libyan frontier. It ii' included in the semi-desert vegetation zone with an attenuated desert climate. An analysis of vegetation along environmental gradients that prevail in the study area using the relative importance values of 55 perennials in 53 stands, fOllowed by multivariate data analysis was presented. Altogether, 1// i!JI'cie.' (75 perennials aw!3(, (';/ill,.:l,-) be!riJIo!I/CJ to 92 genera and 34 families of the flowering plancs were recorded~ Asreraceae, Fabaceae, Chenopodiaceae, Poaceae, Brassicaceae, Caryophyllaceae, Liliaceae and Zygophyllaceae were the largest families, and constitute more than 64 % of the total recorded species. Therophytes and chamaephytes were the most frequent, denoting a
typical desert lifeform spectrum. Phytochorological analyi'is revealed that 45.2 % of the studied species were uniregional, of which 23 % being native to the saharo-arabian chorotype. It also showed the decrease in the numbers of the Mediterranean species and increase of the saharo-arabian species along N-S direction fOrm the see-shore inwards till the Diffa Plateau. Classification of the vegetation was analysed using TWINSPAN technique resulted in the recognition of five vegetation groups, each of definite floristic composition and environmental characteristics, and could be linked to a specific habitat. Haloxylon salicornicum occupied the fOot of the Diffa Plateau, Haloxylon salicornicum- Thymelaea hirsura characterised the sand plains, Thymelaea hirsura-Anabasis articulara inhabited the non-saline depressions, Haloxylon salicornicum-Auiplex por­ rulacoides characterised the saline depressions and Salsola reuan­ dra-Limoniasrrum monoperalum on the coastal salt marshes. Ordination techniques as DCA and CCA were used to examine the relationship between the vegetation and the studied environmental parameters: electric conductivity (EC), pH, calcium carbonate, mois­ ture content, organic matter, silt, clay, K., Mg;+ and altitude. CCA axis 1 showed significant correlation with clay, moisture content, pH, Ee, K', and altitude, while CCA axis 2 was clearly related to pH, Mg;' and altitude. Species richness was correlated with Mg;., while Shannon index was correlated with Na+ and Mg;+.

The present paper investigates heat and mass transfer over a moving porous plate with hydrodynamic
slip and thermal convective boundary conditions and concentration dependent diffusivity. The similarity
representation of the system of partial differential equations of the problem is obtained through Lie group
analysis. The resulting equations are solved numerically by Maple with Runge–Kutta–Fehlberg fourth–
fifth order method. A representative set of results for the physical problem is displayed to illustrate
the influence of parameters (velocity slip parameter, convective heat transfer parameter, concentration
diffusivity parameter, Prandtl number and Schmidt number) on the dimensionless axial velocity, temperature
and concentration field as well as the wall shear stress, the rate of heat transfer and the rate of mass
transfer. The analytical solutions for velocity and temperature are obtained. Very good agreements are
found between the analytical and numerical results of the present paper with published results.

We study a steady laminar 2-D MHD viscous incompressible flow over a permeable flat plate with thermal
convective boundary condition and radiation effects. The viscosity and thermal conductivity of fluid are
assumed to vary linearly with temperature. Similarity representation of the governing partial differential
equations is obtained via group method. Similarity equations are then solved numerically by implicit
finite difference technique. Effects of convective heat transfer parameter (b), radiation parameter (R,)
magnetic field parameter (M), the thermal conductivity parameter (S), suction parameter (fw), Prandtl
number (Pr) and Schmidt number (Sc) on the dimensionless axial velocity, temperature, concentration,
wall temperature, the rate of heat transfer and the rate of mass transfer are investigated. Good agreement
is found between the numerical results of the present paper with published result for special case.

In this paper, heat and mass transfer analysis for boundary layer stagnation-point flow over
a stretching sheet in a porous medium saturated by a nanofluid with internal heat generation/
absorption and suction/blowing is investigated. The governing partial differential
equation and auxiliary conditions are converted to ordinary differential equations with
the corresponding auxiliary conditions via Lie group analysis. The boundary layer temperature,
concentration and nanoparticle volume fraction profiles are then determined
numerically. The influences of various relevant parameters, namely, thermophoresis
parameter Nt, Brownian motion parameter Nb, Lewis number Le, suction/injection parameter
S, permeability parameter k1, source/sink parameter k and Prandtl parameter Pr on
temperature and concentration as well as wall heat flux and wall mass flux are discussed.
Comparison with published results is presented.

Sn–W deposit of the Mueilha mine is one of many
other Sn–W deposits in the Eastern desert of Egypt that
associated with albite granite. Two forms of Sn–Wmineralizations
are known at the Mueilha Sn-mine area, namely fissure
filling quartz veins and greisen. Cassiterite and/or wolframite,
sheelite, and beryl are the main ore minerals in the greisen and
quartz veins. Subordinate chalcopyrite and supergene malachite
and limonite are also observed in the mineralized veins.
To constrain the P–T conditions of the Sn–W mineralizations,
fluid inclusions trapped in quartz and cassiterite, have been
investigated. The following primary fluid inclusion types
are observed: CO2-rich, two-phase (L+V) aqueous, and
immiscible three-phase (H2O–CO2) inclusions. Low temperature
and low salinity secondary inclusions were also detected
in the studied samples. Microthermometric results revealed
that Sn–W deposition seem to have taken place due to
immiscibility at temperature between 260°C and 340°C, and
estimated pressure between 1.2 to 2.2 kb. Microthermometric
results of fluid inclusions in fluorite from fluorite veins
illustrated that fluorite seems to be deposited due to mixing of
two fluids at minimum temperature 140°C and 180°C, and
estimated minimum pressure at 800 bars.

The Neoproterozoic pluton of Gabal Gharib granite
Eastern Desert of Egypt is intruded in subduction-related calcalkaline
granitic rocks of granodiorite to adamellite composition.
A zone of metasomatized granite was developed along
the contacts at the expense of the calc-alkaline granite. The
granite of Gabal Gharib is hypersolvus, composed mainly of
orthoclase-microperthite, quartz, and interstitial arfvedsonite.
Fluorite, zircon, ilmenite, allanite, and astrophyllite are the
main accessories. Pegmatite pods as well as miarolitic cavities
(mineral-lined cavities) are common and ranging in size from
a few millimeters to 50 cm. Rare-metal minerals such as
columbite, cassiterite, and fluorite have been identified from
the miarolitic cavities. Geochemical studies revealed that
Gabal Gharib granite is a highly fractionated granite,
homogeneous in composition, with high contents of SiO2,
and alkalis, high Ga/Al, and Fe/Mg ratios, and low concentrations
of Al, Mg, and CaO relative to granodiorite–
adamellite country rocks. Gabal Gharib granite is metaluminous
to peralkaline with ASI (0.94–1.07). Trace element
characteristics of Gabal Gharib granite include abundances of
Rb, Nb, Ta, Sn, Th, U, Y, Ga, Zn, rare earth elements (REEs,
except Eu), and F, and depletion in Sr, and Ba relative to
granodiorite–adamellite country rocks. It has the geochemical
characteristic of anorogenic A-type granite. The uniform
trends of differentiation, normal REE distribution patterns,
and low calculated tetrad effects of REE (<0.2) indicate that
the effect of post-magmatic subsolidus processes were
minimal in the studied granite. Fluid inclusions were studied
in quartz crystals from Gabal Gharib granite, quartz pods, and
metasomatized granite. The study revealed the presence of high-temperature (480–550°C), high-salinity (19.45–39.13 wt.
% NaCl eq.) primary inclusions in both metasomatized and
rare-metal granites coexisting with melt inclusions and
medium-temperature (350–450°C), medium-salinity (10–
16 wt.% NaCl esq.) aqueous inclusions coexisting
hydrocarbon-bearing inclusions. Hydrocarbon is represented
by magmatic CH4 in Gabal Gharib granite, while heavier
aliphatic compounds may be present in quartz pods. Melt
inclusions with temperatures of homogenization >600°C were
also reported. Petrographic, geochemical, and fluid inclusion
studies constrain that the peralkaline anorogenic granite of
Gabal Gharib was derived from highly evolved magma
probably originated by fractional crystallization of mantle
source.

Rare-metal granites of Nuweibi and Abu Dabbab,
central Eastern Desert of Egypt, have mineralogical and geochemical
specialization. These granites are acidic, slightly
peraluminous to metaaluminous, Li–F–Na-rich, and Sn–Nb–
Ta-mineralized. Snowball textures, homogenous distribution
of rock-forming accessory minerals, disseminated mineralization,
and melt inclusions in quartz phenocrysts are typical
features indicative of their petrographic specialization.
Geochemical characterizations are consistent with low-P-rare
metal granite derived from highly evolved I-type magma in
the late stage of crystallization. Melt and fluid inclusions were
studied in granites, mineralized veins, and greisen. The study
revealed that at least two stages of liquid immiscibility played
an important role in the evolution of magma–hydrothermal
transition as well as mineral deposition. The early stage is
melt/fluid case. This stage is represented by the coexistence of
type-B melt and aqueous-CO2 inclusions in association with
topaz, columbite–tantalite, as well as cassiterite mineral inclusions.
This stage seems to have taken place at the late magmatic
stage at temperatures between 450 °C and 550 °C. The
late magmatic to early hydrothermal stage is represented by
vapor-rich H2O and CO2 inclusions, sometimes with small
crystallized silicic melt in greisen and the outer margins of the
mineralized veins. These inclusions are associated with beryl,
topaz, and cassiterite mineralization and probably trapped at
400 °C. The last stage of immiscibility is fluid–fluid and
represented by the coexisting H2O-rich and CO2-rich inclusions.
Cassiterite, wolframite ± chalcopyrite, and fluorite are
the main mineral assemblage in this stage. The trapping temperature
was estimated between 200 °C and 350 °C. The latest
phase of fluid is low-saline, low-temperature (100–180 °C),
and liquid-rich aqueous fluid.

The Qreiya Beds that record the ‘mid-Paleocene
event’ at Gabal Nezzazat occur within the Igorina albeari
(P3b) Zone and constitute part of a 14-m thick shale succession
that ranges in age from Early to Late Paleocene. They are
composed of four alternating dark grey and brown shale
beds, which are thinly laminated, phosphatic, organic-rich
and extremely sulphidic. They are characterized by distinct
enrichment and high peak anomalies in chalcophiles (Zn, Co,
Ni, Cu and Pb) and organic association elements (V and Cr),
especially within the brown organic-rich beds. It is concluded
that these elements are incorporated into the phosphatic debris,
sulphides and organic matter. In contrast, the grey beds are
enriched in clay minerals and quartz. Clay mineral assemblages
indicate alternating periods of warm/humid climate (high
kaolinite) and dry climate (low kaolinite) during the formation
of the grey and brown beds, respectively. The sediments of
the Qreiya Beds yield lithological, biotic, geochemical and
mineralogical data indicative of suboxic/anoxic marine environments
as a result of high productivity and/or upwelling.
The top metre of the succession below the Qreiya Beds is
characterized by a progressive change from faunas dominated
by praemurcurids to faunas dominated by Morozovilids, and
by a progressive upward decrease in δ13Ccarb and δ18Ocarb
values. The foraminiferal faunal change may reflect shallowing
and warming preceding deposition of the Qreiya Beds. The
change in isotopic values is inferred to be the result of surface weathering, fluvial input and diagenesis with no evidence of
any primary change that could support presence of a hyperthermal
event.