Long-lived Transfer-Zone Paleovalleys in Mountain Belts: An Example from the Tertiary of the Spanish Pyrenees

1997 ◽  
Vol Vol. 67 ◽  
Author(s):  
Stephen J. Vincent (*), Trevor Elli
Keyword(s):  
Spanish Pyrenees ◽  
Mountain Belts ◽  
Transfer Zone

Sedelnikovaea baicalensis (Lecanoraceae) — new lichen genus and species for Europe

2018 ◽  
Vol 52 (2) ◽  
pp. 407-416
Author(s):  
T. V. Makryi
Keyword(s):  
Central Asia ◽  
Lichen Species ◽  
Significant Part ◽  
The Urals ◽  
Southern Siberia ◽  
Central Asian ◽  
Northeastern Siberia ◽  
Mountain Belts ◽  
First Time ◽  
Vast Range

Sedelnikovaea baicalensis, the Siberian-Central Asian lichen species, is recorded for the first time for Europe. Based on all the known localities, including those first-time reported from Baikal Siberia, the peculiarities of the ecology and distribution of this species are discussed, the map of its distribution is provided. It is concluded that the species was erroneously considered earlier as a Central Asian endemic. The center of the present range of this lichen is the steppes of Southern Siberia and Mongolia. Assumptions are made that S. baicalensis is relatively young (Paleogene-Neogene) species otherwise it would have a vast range extending beyond Asia, and also that the Yakut locations of this species indicate that in the Pleistocene its range was wider and covered a significant part of the Northeastern Siberia but later underwent regression. Based on the fact that in the mountains of Central Asia the species is found only in the upper mountain belts, it is proposed to characterize it as «cryo-arid xerophyte» in contrast to «arid xerophytes». A conclusion is made that the presence of extensive disjunctions of S. baicalensis range between the Southern Pre-Urals and the Altai-Sayan Mountains or the Mountains of Central Asia is unlikely; the lichen is most likely to occur in the Urals and most of Kazakhstan.

scholarly journals Analysis of the Snow Water Equivalent at the AEMet-Formigal Field Laboratory (Spanish Pyrenees) During the 2019/2020 Winter Season Using a Stepped-Frequency Continuous Wave Radar (SFCW)

2021 ◽  
Vol 13 (4) ◽  
pp. 616
Author(s):  
Rafael Alonso ◽  
José María García del Pozo ◽  
Samuel T. Buisán ◽  
José Adolfo Álvarez
Keyword(s):  
Software Defined Radio ◽  
Continuous Wave ◽  
Snow Water Equivalent ◽  
Cosmic Ray ◽  
Relative Dielectric Permittivity ◽  
Near Surface ◽  
Wave Radar ◽  
Spanish Pyrenees ◽  
Snow Water ◽  
Stepped Frequency

Snow makes a great contribution to the hydrological cycle in cold regions. The parameter to characterize available the water from the snow cover is the well-known snow water equivalent (SWE). This paper presents a near-surface-based radar for determining the SWE from the measured complex spectral reflectance of the snowpack. The method is based in a stepped-frequency continuous wave radar (SFCW), implemented in a coherent software defined radio (SDR), in the range from 150 MHz to 6 GHz. An electromagnetic model to solve the electromagnetic reflectance of a snowpack, including the frequency and wetness dependence of the complex relative dielectric permittivity of snow layers, is shown. Using the previous model, an approximated method to calculate the SWE is proposed. The results are presented and compared with those provided by a cosmic-ray neutron SWE gauge over the 2019–2020 winter in the experimental AEMet Formigal-Sarrios test site. This experimental field is located in the Spanish Pyrenees at an elevation of 1800 m a.s.l. The results suggest the viability of the approximate method. Finally, the feasibility of an auxiliary snow height measurement sensor based on a 120 GHz frequency modulated continuous wave (FMCW) radar sensor, is shown.

scholarly journals A Case Study of a Large Unstable Mass Stabilization: “El Portalet” Pass at the Central Spanish Pyrenees

2021 ◽  
Vol 11 (16) ◽  
pp. 7176
Author(s):  
Guillermo Cobos ◽  
Miguel Ángel Eguibar ◽  
Francisco Javier Torrijo ◽  
Julio Garzón-Roca
Keyword(s):  
Water Table ◽  
Critical Factor ◽  
Slope Stabilization ◽  
Survey Techniques ◽  
Geotechnical Investigations ◽  
Spanish Pyrenees ◽  
Parking Lot ◽  
Unstable Slope ◽  
Total Stability

This case study presents the engineering approach conducted for stabilizing a landslide that occurred at “El Portalet” Pass in the Central Spanish Pyrenees activated due to the construction of a parking lot. Unlike common slope stabilization cases, measures projected here were aimed at slowing and controlling the landslide, and not completely stopping the movement. This decision was taken due to the slow movement of the landslide and the large unstable mass involved. The degree of success of the stabilization measures was assessed by stability analyses and data obtained from different geotechnical investigations and satellite survey techniques such as GB-SAR and DinSAR conducted by different authors in the area under study. The water table was found to be a critical factor in the landslide’s stability, and the tendency of the unstable slope for null movement (total stability) was related to the water table lowering process, which needs more than 10 years to occur due to regional and climatic issues. Results showed a good performance of the stabilization measures to control the landslide, demonstrating the effectiveness of the approach followed, and which became an example of a good response to the classical engineering duality cost–safety.

scholarly journals Trans-lithospheric diapirism explains the presence of ultra-high pressure rocks in the European Variscides

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Petra Maierová ◽  
Karel Schulmann ◽  
Pavla Štípská ◽  
Taras Gerya ◽  
Ondrej Lexa
Keyword(s):  
High Pressure ◽  
Numerical Models ◽  
Classical Concept ◽  
Plate Interface ◽  
Ultra High Pressure ◽  
Common Process ◽  
Mountain Belts ◽  
Collisional Orogens ◽  
Rock Association ◽  
European Variscides

AbstractThe classical concept of collisional orogens suggests that mountain belts form as a crustal wedge between the downgoing and overriding plates. However, this orogenic style is not compatible with the presence of (ultra-)high pressure crustal and mantle rocks far from the plate interface in the Bohemian Massif of Central Europe. Here we use a comparison between geological observations and thermo-mechanical numerical models to explain their formation. We suggest that continental crust was first deeply subducted, then flowed laterally underneath the lithosphere and eventually rose in the form of large partially molten trans-lithospheric diapirs. We further show that trans-lithospheric diapirism produces a specific rock association of (ultra-)high pressure crustal and mantle rocks and ultra-potassic magmas that alternates with the less metamorphosed rocks of the upper plate. Similar rock associations have been described in other convergent zones, both modern and ancient. We speculate that trans-lithospheric diapirism could be a common process.

The stratigraphy of a proximal late Hercynian pyroclastic sequence: the Vilancós region of the Pyrenees

1991 ◽  
Vol 128 (2) ◽  
pp. 111-128 ◽  
Author(s):  
J. S. Gilbert
Keyword(s):  
Explosive Eruptions ◽  
Rhyolite Lava ◽  
Geochemical Fingerprinting ◽  
Garnet Composition ◽  
Spanish Pyrenees ◽  
Volcanic Formation ◽  
Flow Deposit ◽  
Hercynian Orogeny ◽  
Mass Flow Deposits ◽  
Crustal Differentiation

AbstractVolcanic activity, the result of crustal differentiation during the Hercynian orogeny, generated eight explosive eruptions in the Vilancós region of the Spanish Pyrenees. The volcanic products comprise the Erill Castell Volcanic Formation of Stephanian age, which crops out as a 20 km long, WNW-trending strip < 2 km wide dipping steeply to the south.The Vilancós region represents a small fragment of an originally extensive regional terrain of silicic centres.The explosive eruptions mainly generated strongly peraluminous and phenocrystal garnet-bearing subaerial ignimbrite facies. Proximal intra-formational breccias represent a substantial volume of the preserved erupted product and one phreatoplinian deposit is exposed. Mass-flow deposits are common, and small-volume basalt, andesite and rhyolite lava flows, minor tuffs and palaesols also occur.Electron microprobe data show that each garnet-bearing member of the Vilancós region has a distinct garnet composition. This is used as geochemical fingerprinting tool to aid mapping and correlation between proximal intra-formational breccias and ignimbrite of the same eruption. Within one debris-flow deposit (the Vilancós Breccia Member) at least three garnet populations occur. Two of these are derived from pyroclastic members within the mapped region, the other comes from an unexposed rhyolite lava source.

Tectonic inversion and structural inheritance in mountain belts

2006 ◽  
Vol 28 (11) ◽  
pp. 1891-1892 ◽  
Author(s):  
Rob Butler ◽  
Enrico Tavarnelli ◽  
Mario Grasso
Keyword(s):  
Structural Inheritance ◽  
Tectonic Inversion ◽  
Mountain Belts
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