@misc{SodoudiYuanKindetal.2013, author = {Sodoudi, Forough and Yuan, Xiaohui and Kind, Rainer and Lebedev, Sergei and Adam, Joanne M-C. and K{\"a}stle, Emanuel and Tilmann, Frederik}, title = {Seismic evidence for stratification in composition and anisotropic fabric within the thick lithosphere of Kalahari Craton}, series = {Geochemistry, geophysics, geosystems}, volume = {14}, journal = {Geochemistry, geophysics, geosystems}, number = {12}, publisher = {American Geophysical Union}, address = {Washington}, issn = {1525-2027}, doi = {10.1002/2013GC004955}, pages = {5393 -- 5412}, year = {2013}, abstract = {Based on joint consideration of S receiver functions and surface-wave anisotropy we present evidence for the existence of a thick and layered lithosphere beneath the Kalahari Craton. Our results show that frozen-in anisotropy and compositional changes can generate sharp Mid-Lithospheric Discontinuities (MLD) at depths of 85 and 150-200 km, respectively. We found that a 50 km thick anisotropic layer, containing 3\% S wave anisotropy and with a fast-velocity axis different from that in the layer beneath, can account for the first MLD at about 85 km depth. Significant correlation between the depths of an apparent boundary separating the depleted and metasomatised lithosphere, as inferred from chemical tomography, and those of our second MLD led us to characterize it as a compositional boundary, most likely due to the modification of the cratonic mantle lithosphere by magma infiltration. The deepening of this boundary from 150 to 200 km is spatially correlated with the surficial expression of the Thabazimbi-Murchison Lineament (TML), implying that the TML isolates the lithosphere of the Limpopo terrane from that of the ancient Kaapvaal terrane. The largest velocity contrast (3.6-4.7\%) is observed at a boundary located at depths of 260-280 km beneath the Archean domains and the older Proterozoic belt. This boundary most likely represents the lithosphere-asthenosphere boundary, which shallows to about 200 km beneath the younger Proterozoic belt. Thus, the Kalahari lithosphere may have survived multiple episodes of intense magmatism and collisional rifting during the billions of years of its history, which left their imprint in its internal layering.}, language = {en} } @article{MohsenAschKindetal.2013, author = {Mohsen, Ayman and Asch, G{\"u}nter and Kind, Rainer and Mechie, James and Weber, Michael H.}, title = {The lithosphere-asthenosphere boundary in the eastern part of the Dead Sea Basin (DSB) from S-to-P receiver functions}, series = {Arabian journal of geosciences}, volume = {6}, journal = {Arabian journal of geosciences}, number = {7}, publisher = {Springer}, address = {Heidelberg}, issn = {1866-7511}, doi = {10.1007/s12517-011-0503-4}, pages = {2343 -- 2350}, year = {2013}, abstract = {Clear S-to-P converted waves from the crust-mantle boundary (Moho) and lithosphere-asthenosphere boundary (LAB) have been observed on the eastern part of the Dead Sea Basin (DSB), and are used for the determination of the depth of the Moho and the LAB. A temporary network consisting of 18 seismic broad-band stations was operated in the DSB region as part of the DEad Sea Integrated REsearch project for 1.5 years beginning in September 2006. The obtained Moho depth (similar to 35 km) from S-to-P receiver functions agrees well with the results from P-to-S receiver functions and other geophysical data. The thickness of the lithosphere on the eastern part of the DSB is about 75 km. The results obtained here support and confirm previous studies, based on xenolith data, geodynamic modeling, heat flow observations, and S-to-P receiver functions. Therefore, the lithosphere on the eastern part of the DSB and along Wadi Araba has been thinned in the Late Cenozoic, following rifting and spreading of the Red Sea. The thinning of the lithosphere occurred without a concomitant change in the crustal thickness and thus an upwelling of the asthenosphere in the study area is invoked as the cause of the lithosphere thinning.}, language = {en} }