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By using SatGravRET2014 gravito-topography model, based also on satellite GRACE and GOCE data, we computed and plotted the gravity disturbances, the Marussi tensor of the second derivatives of the disturbing potential, the gravity invariants and their specific ratio, the strike angle and the virtual deformations for the Lake Vostok (LV) area in Antarctica. This set of gravity “aspects” provides more detailed and clearer information than the traditional gravity anomalies. Maps with the bedrock topography from Bedmap 2 are added. Some of our estimates and results confirm independent findings of other specialists, some results presented here are new. LV is divided not only into its N and S parts by a ridge, but also to E and W parts. A tension across LV has a prevailing direction E-W. We identified at least three candidates for subglacial lakes south of the lakes 90 E and Sovetskaya. In the gravity aspects this area looks like a basin, where the mentioned lakes might be just a remnant of a large bowl; the orientation of this basin is the same as that of LV; the size comparable to LV. A subglacial connection between all the mentioned lakes is possible and documented via the gravity aspects, namely by the virtual deformations. [ABSTRACT FROM AUTHOR]

The goal of this study is to demonstrate that and how the recent gravitational and topographic data support the findings made by geologists and others as for the existence of the paleolakes and paleoriver systems, now buried under the sands of Sahara. It is always important and useful to have such an independent analysis supporting certain results, and this paper is such a case. We make use of the gravity disturbances (or anomalies), the Marussi tensor of the second derivatives of the disturbing geopotential, the gravitational invariants and their certain ratio, the strike angle and the virtual deformations. The geopotential is represented by the global combined (from satellite and terrestrial data) high-resolution gravity field model EIGEN 6C4 (till degree and order 2160 in spherical harmonic expansion). The topography is derived from the ASTER GDEM and ETOPO 1 models (both are used). With all these data, we confirm the existence of huge paleolakes or paleoriver systems under the Saharan sands known or anticipated in an independent way by geologists for the lakes MegaChad, Fazzan and Chotts; for Tamanrasset river valley; and Kufrah Basin, presumptive previous flow of the Nile River. Moreover, we suggest a part of the Grand Egyptian Sand Sea as another 'candidate' for a paleolake and hence for a follow-up survey. [ABSTRACT FROM AUTHOR]

Ostrich eggs are sought after not only for their nutrition content, but also for use in artefact industries. The egg shells can be used to make containers or items of personal decoration, such as pendants and disc beads. The latter artefacts and the process of their manufacturing were studied on the material gained through excavation in 2012 of Sounding 2 (20 m2) at the Mesolithic settlement and burial ground of Sphinx (SBK.W-60) at Jebel Sabaloka (West Bank) in central Sudan. [ABSTRACT FROM AUTHOR]

Copyright of Prague Egyptological Studies / Prazské Egyptologické Studie is the property of Charles University Prague, Faculty of Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Památky Archeologické is the property of Academy of Sciences of the Czech Republic, Institute of Archaeology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Normapolles pollen, fern spores, recent fungi and other palynomorphs were traced and identified from a sample of calcareous/ /clayey deposits from the Gombasek Quarry in eastern Slovakia (Rožnava district). Normapolles, pollen of the extinct angiospermous plants, dominated the spectrum, spores of ferns were also frequent. Presence of these types indicate a Mesozoic (Upper Cretaceous) to Early Paleogene age of the source rocks. The assemblage is mixed with specimens of recent fungi spores , remains of algae and rare gymnosperm and angiosperm pollen grains (Pinus, Asteraceae). Significant Tertiary (Paleogene) taxa were not discovered there. The study produced several new records of taxa which had not been found at this locality previously . [ABSTRACT FROM AUTHOR]

The so-called “lake or swampy” dark colored deposits along or to the west of both the White and Main Niles, which were not historically inundated by the Nile as a whole, have been recorded recently in association with Mesolithic occupation. What are the possible formation processes of these deposits and what is their potential for understanding the environmental record in relation to Mesolithic occupation? New insight into this issue might be brought to the forefront by the findings in the Rocky Cities area at the south-western edge of Jebel Sabaloka by the Sixth Nile Cataract in central Sudan. The study deposits were evaluated in terms of sedimentology, micromorphology, chemical composition, grain size and magnetic parameters. The properties detected in the study section correspond to no less than three different phases of development. The lowermost part represents a saprolite horizon of granitic rocks exposed to weathering during the wet period, which resulted in alkaline conditions (1st phase of formation process). The occurrence of shells of Bulinus forskalii retrieved from the uppermost layer suggests that there was an anoxic environment in the past, which may be linked to the conditions of the present-day Sahel and subsequent attraction of this area for occupation during the Mesolithic period. Deposition of the acidic colluvia from the surrounding granitic rocks in this environment resulted in post-depositional processes involving Fe and Mn impregnation, leading to the black coloring (2nd phase of the formation process). The third phase of the formation processes is connected with the development of recent aridisols. [ABSTRACT FROM AUTHOR]

Uranium deposit located near the Nahošín village, 10 km SW of Blatná (southwestern Bohemia, Czech Republic) was one of the last (1978 - 1989) explored uranium deposits in the Czech Republic. The deposit Nahošín is situated in the Chanovice part of Central Bohemian Plutonic Complex represented here by the Blatná type of granodiorite. It belongs to metasomatic uranium deposit developed in granitoids. The metasomatic uranium mineralization in granitoids is bound to strongly hydrothermally altered zone (1 to 5 m wide), represented by disseminated coffinite I in association with pyrite, calcite and sporadic galena and clausthalite. The altered granodiorite is reddish in colour, shows indications of leached quartz and the formation of hematite, chlorite, Ti - minerals, albite, K-feldspar and calcite.The increased porosity of intensively altered granodiorite is a characteristic feature. The significant extent of younger (regenarated) contrast vein uranium mineralization was also found here. The vein uranium mineralization occurred at crushed and brecciated zones of hydrothermally altered granitoide. It is represented by uraninite (usually partly replaced by coffinite II) in calcite gangue in association with pyrite and minerals of the galena - clausthalite solid solution. The δ13C and δ18O data of hydrothermal calcite associated with uraninite and coffinite of the younger vein mineralization indicate low temperature of deposition (<150 °C) and a presence of relatively shallow circulating fluids of meteoric provenance. Carbon was most probably derived from more sources, with participation of exogenous carbon during the youngest mineralization stages. Both types uranium mineralization at the Nahošín ore deposit are of late Variscan age probably. [ABSTRACT FROM AUTHOR]