The Magnetic And Density Characteristics Of The Lithosphere Beneath The Eastern Mediterranean Sea Area And Its Tectonic Implications

The Eastern Mediterranean,situated in the Neo-Tethyan collision zone,consists mainly of the Mesozoic terrane belt and the adjoining oceanic crust complex of the northern part of the Sinai plate.The Eastern Mediterranean region has a complicated geological history that extended from late Triassic to early Jurassic ages.The various stratigraphic evolution of the Eastern Mediterranean region represents the complicated Cenozoic boundaries and pre-Cenozoic.The magmatic characteristics of the Levant were investigated by combining recompiled regional scale magnetic and gravity maps and previous interpretations.The integrated interpretation of magnetic and local gravity anomalies allowed for the estimation of depth and size of magmatic bodies.The Curie point depth(CPD)has been established to enhance the determination of magnetic sources average bottom depth.In this study,the CPD and heat flow regime in the Eastern Mediterranean will be investigated in order to understand the relationship between them.When CPD and heat flow values are determined together,we can understand the types and process of geothermal resources formation.CPD and heat flow will be obtained by applying the method of spectral analysis on magnetic data which was obtained from Earth Magnetic Anomaly Grid(EMAG3).CPD values were found to be approximately 23 km under the Eratosthenes Seamount,while in Cyprus they have been established to be around 18 km.This indicates that the heat flow has higher values of about 100 m W/m~2,in the northern part of the Eratosthenes Seamount,where the thinnest crust is located.However,lower values reach 80 m W/m~2 in the southern parts.The variations of Moho surface inverted from Bouguer gravity data beneath the northwestern of the Arabian plate.The results obtained by applying 3DINVER program developed in MATLAB environment employing the Parker-Oldenburg method.The findings reveal that the maximum Moho depth observed in the western Arabian shield part extends to over 40 km,and the minimum values of 16 to 20 km mainly concentrated beneath the Mediterranean Sea.This study’s innovative aspect is the exponential decrease in density contrast within the sediment-basement interface in the Syrian portion.The gravity anomaly of the sediments was calculated using an exponentially varying density contrast with depth.To validate our inverted results,they were compared to seismic findings,revealing a strong correlation.A 3-D density structure of the lithosphere and upper-mantle beneath the Eastern Mediterranean Sea(EMS)and adjacent region was constructed based on gravity anomaly inversion constrained by a seismic tomography model.In this study,we have removed the gravity effects of terrain and crust from the observed gravity field(EIGEN-6C4),in order to obtain the residual mantle gravity anomaly(RMGA),which was used to investigate the lithospheric and the upper-mantle density distribution.The 3-D inversion process is constrained by an initial density model derived from shear-wave velocity model(SL2013sv).The results highlight specific density distribution characteristics in the lithosphere and the upper mantle that could be related to the tectonic importance of the Mediterranean Sea and its surrounding region.These findings show that the density structure of the ESM is influenced more by compositional variations than thermal ones,and the thin,dense,and cold layer is located in the lithosphere beneath the west ESM,whereas the thick,soft,and low-density layer is located below the lithosphere and might be linked to the asthenosphere in the region from west to east at a depth of 100 km.The primary objective of this study is to examine the regional distribution of Curie depths and delineate key tectonic and geodynamic features of the regional deep structure.This will be achieved by integrating a regional analysis of geophysical data,including magnetic and gravity data,to construct new maps of structures.To further understanding the Eastern Mediterranean Sea and its surrounding regions we will extend the study area and employ gravity data to discuss the following:·Local Moho distribution in the Eastern Mediterranean region derived from satellite-based gravity inversion:Eastern Mediterranean Sea.·3-D density structure of the upper-mantle from gravity inversion constrained by a seismic velocity model:A case study of the Eastern Mediterranean Sea and surrounding region.These new maps help gain a deeper understanding of the dynamics of lithosphere and upper-mantle that potentially associated with the tectonic signification beneath the Eastern Mediterranean Sea and adjacent region.