The Southern Flank of Europe does not finish in the Sands of Sahara[1]

2021 ◽  
Author(s):  
José Francisco Pavia
Keyword(s):  
1999 ◽  
Vol 36 (10) ◽  
pp. 1655-1669 ◽  
Author(s):  
Jacquelyn E Stevens ◽  
J Brendan Murphy ◽  
Fred W Chandler

Geochemical and isotopic data from the clastic rocks of the Namurian Lismore Formation in mainland Nova Scotia identify key episodes of tectonic activity during the development of the Maritimes Basin in Atlantic Canada. The Lismore Formation forms part of the Mabou Group and is an upward-coarsening 2500 m thick fluvial sequence deposited in the Merigomish sub-basin along the southern flank of the Maritimes Basin. Based on stratigraphic evidence, the Lismore Formation can be divided into upper and lower members which reflect variations in depositional environment and paleoclimate. The geochemical and isotopic data may also be subdivided into two groupings that primarily reflect varying contributions from accessory phases, clay minerals, or rock fragments. This subdivision occurs 115 m above the base of the upper member. The data from the lower grouping (group A) show an important contribution from underlying Silurian rocks, with a relatively minor contribution from Late Devonian granitoid rocks from the adjacent Cobequid Highlands and possibly metasedimentary rocks from the Meguma Terrane to the south. The data from the upper grouping (group B) reveal a more important contribution from the Cobequid Highlands granitoid rocks. This variation in geochemistry is thought to constrain the age of renewed motion and uplift along the faults along the southern flank of the Maritimes Basin and, more generally, suggests that geochemical and isotopic data of continental clastic rocks may help constrain the age of tectonic events that influence deposition of basin-fill rocks.


1969 ◽  
Vol 6 (5) ◽  
pp. 1095-1104 ◽  
Author(s):  
Gerhard H. Eisbacher

The east-trending Cobequid Fault separates pre-Carboniferous rocks of the Cobequid Mountains to the north from Carboniferous clastic rocks along the southern flank of the mountains. A detailed study of the fault zone revealed tie predominance of right-lateral displacements. The orientation of the stress field that existed during deformation along the fault trace was determined by the study of systematic fractures in pebbles within Carboniferous conglomerate. Maximum compressive stress was aligned in a NW–SE direction, being compatible with the orientation of the displacement vectors in the fault zone. Transcurrent movement along the Cobequid Fault occurred in late Pennsylvanian time and involved both Carboniferous and pre-Carboniferous rocks; total displacement is unknown.


1939 ◽  
Vol 59 (2) ◽  
pp. 213-228
Author(s):  
Umberto Zanotti-Bianco

In my previous report (JHS, 1938, p. 247) I spoke of the work being carried on at Syracuse to bring to light the remains of the temple of Apollo. The east, north, and west sides had been freed by then, whilst the southern side was still hidden under seventeenth- and eighteenth-century houses, so that it had never been possible to dig trial trenches through their foundations to ascertain if any part of the temple was preserved there. The demolition of the houses and the excavation under the modern ground level beginning from the south-west angle have fully satisfied our hopes. Five columns of the southern flank of the peristasis have appeared, preserved to a height of over 2 metres, with the stylobate beneath them (Fig. 1): only the angle column had been destroyed during the building of the walls of the Spanish barracks. The cella is equally well preserved, and a third of its total length has already been liberated, although the work is in temporary suspense owing to unsettled disputes with the owners of the houses. The southern flank of the archaic Syracusan temple appears to be in much better condition than the others.


2016 ◽  
Vol 46 (11) ◽  
pp. 3365-3384 ◽  
Author(s):  
Xavier Capet ◽  
Guillaume Roullet ◽  
Patrice Klein ◽  
Guillaume Maze

AbstractThis study focuses on the description of an oceanic variant of the Charney baroclinic instability, arising from the joint presence of (i) an equatorward buoyancy gradient that extends from the surface into the ocean interior and (ii) reduced subsurface stratification, for example, as produced by wintertime convection or subduction. This study analyzes forced dissipative simulations with and without Charney baroclinic instability (C-BCI). In the former, C-BCI strengthens near-surface frontal activity with important consequences in terms of turbulent statistics: increased variance of vertical vorticity and velocity and increased vertical turbulent fluxes. Energetic consequences are explored. Despite the atypical enhancement of submesoscale activity in the simulation subjected to C-BCI, and contrary to several recent studies, the downscale energy flux at the submesoscale en route to dissipation remains modest in the flow energetic equilibration. In particular, it is modest vis à vis the global energy input to the system, the eddy kinetic energy input through conversion of available potential energy, and the classical inverse cascade of kinetic energy. Linear stability analysis suggests that the southern flank of the Gulf Stream may be conducive to oceanic Charney baroclinic instability in spring, following mode water formation and upper-ocean destratification.


2013 ◽  
Vol 7 (4) ◽  
pp. 3337-3378 ◽  
Author(s):  
P. Wagnon ◽  
C. Vincent ◽  
Y. Arnaud ◽  
E. Berthier ◽  
E. Vuillermoz ◽  
...  

Abstract. In the Everest region, Nepal, ground-based monitoring programs were started on the debris-free Mera Glacier (27.7° N, 86.9° E; 5.1 km2, 6420 to 4940 m a.s.l.) in 2007 and on the small Pokalde Glacier (27.9° N, 86.8° E; 0.1 km2, 5690 to 5430 m a.s.l., ∼ 25 km North of Mera Glacier) in 2009. These glaciers lie on the southern flank of the central Himalaya under the direct influence of the Indian monsoon and receive more than 80% of their annual precipitation in summer (June to September). Despite a large inter-annual variability with glacier-wide mass balances ranging from −0.77± 0.40 m w.e. in 2011–2012 (Equilibrium-line altitude (ELA) at ∼ 6055 m a.s.l.) to + 0.46 ± 0.40 m w.e. in 2010–2011 (ELA at ∼ 5340 m a.s.l.), Mera Glacier has been shrinking at a moderate mass balance rate of −0.10± 0.40 m w.e. yr−1 since 2007. Ice fluxes measured at two distinct transverse cross sections at ∼ 5350 m a.s.l. and ∼ 5520 m a.s.l. confirm that the mean state of this glacier over the last one or two decades corresponds to a limited mass loss, in agreement with remotely-sensed region-wide mass balances of the Everest area. Seasonal mass balance measurements show that ablation and accumulation are concomitant in summer which in turn is the key season controlling the annual glacier-wide mass balance. Unexpectedly, ablation occurs at all elevations in winter due to wind erosion and sublimation, with remobilized snow likely being sublimated in the atmosphere. Between 2009 and 2012, the small Pokalde Glacier lost mass more rapidly than Mera Glacier with respective mean glacier-wide mass balances of −0.72 and −0.26 ± 0.40 m w.e. yr−1. Low-elevation glaciers, such as Pokalde Glacier, have been usually preferred for in-situ observations in Nepal and more generally in the Himalayas, which may explain why compilations of ground-based mass balances are biased toward negative values compared with the regional mean under the present-day climate.


Zootaxa ◽  
2021 ◽  
Vol 5061 (3) ◽  
pp. 432-450
Author(s):  
GILLES VINÇON ◽  
BERTRAND LAUNAY ◽  
JEAN-PAUL G. REDING

Two new species of Protonemura Kempny, 1898, P. lupina sp. n., from the Castellane Prealps and the southern Mercantour region in the French Maritime Alps, and P. alexidis sp. n., from the southern flank of the Massif Central, are described, illustrated, and compared to their closest relative species P. risi (Jacobson & Bianchi, 1905) and P. spinulosa (Navás, 1921). Information on distribution and ecological preferences of these new species is provided.  


1955 ◽  
Vol S6-V (1-3) ◽  
pp. 125-134 ◽  
Author(s):  
Madeleine Neumann
Keyword(s):  

Abstract Describes an orthophragmine foraminiferal fauna (including Discocyclina trabayensis n.sp.) from lower Lutetian (Tertiary) Xanthopsis durourii-bearing marls which outcrop on the southern flank of the Audignon ridge and, farther west, on the flanks of the Louer dome, Aquitaine, France.


2019 ◽  
pp. 90-111
Author(s):  
Tom Lansford
Keyword(s):  

Radiocarbon ◽  
2012 ◽  
Vol 54 (1) ◽  
pp. 91-105 ◽  
Author(s):  
Luca C Malatesta ◽  
Sébastien Castelltort ◽  
Simone Mantellini ◽  
Vincenzo Picotti ◽  
Irka Hajdas ◽  
...  

The oasis of Samarkand in the Middle Zeravshan Valley (modern Uzbekistan) was a major political and economic center in ancient western Central Asia. The chronology of its irrigation system was, until now, only constrained by the quality and quantity of archaeological findings and several different hypotheses have been proposed for it. We use a new approach combining archaeological surveying, radiocarbon dating, sedimentary analysis, and the numerical modeling of a flood event to offer new evidence for, and quantitative dating of, the development of irrigation system on the southern flank of the Middle Zeravshan Valley. We analyzed 13 bones and charcoals from 3 archaeological sites and obtained new 14C ages from Afrasiab (ancient Samarkand), a dwelling damaged by flooding in the 2nd century AD (site code: SAM-174) and the fortress of Kafir Kala. We established the origin of sedimentary deposits at the sites to infer the presence of the 2 most important canals of the southern flank: the Dargom and the Yanghiaryk. Finally, we show with a numerical model of overland flow that a natural flood was unlikely to have produced the damage observed at SAM-174. The combined results of the study indicate that the canals south of Samarkand existed, and were mainly developed, in the 2nd century AD and were not connected to the main feeding canal of Afrasiab at that time.


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