Search results for "Boulder"
showing 8 items of 8 documents
Boulder coastal deposits at Favignana Island rocky coast (Sicily, Italy): Litho-structural and hydrodynamic control
2018
Boulders are frequently dislodged from rock platforms, transported and deposited along coastal zones by high-magnitude storm waves or tsunamis. Their size and shape are often controlled by the thickness of bedding planes as well as by high-angle to bedding fracture network. We investigate these processes along two coastal areas of Favignana Island by integrating geological data for 81 boulders, 49 rupture surfaces (called sockets) and fracture orientation and spacing with four radiocarbon dates, numerical hydrodynamic analysis, and hindcast numerical simulation data. Boulders are scattered along the carbonate platform as isolated blocks or in small groups, which form, as a whole, a disconti…
Late Cretaceous echinoderm ‘odds and ends’ from the Low Countries
2018
From various levels within the Gulpen and Maastricht formations (upper lower to upper upper Maastrichtian, c. 69.5–66 Ma) in the extended type area of the Maastrichtian Stage (southeast Netherlands, northeast Belgium and the Aachen area in Germany), a few recent additions to echinoderm faunas are illustrated and briefly discussed. Added are some erratic, flint-preserved, pre-Maastrichtian echinoid taxa from Pleistocene fluvial gravel deposits; these are of palaeogeographical interest. Crinoids include the comatulid Semiometra saskiae with traces of sublethal predation and several bourgueticrinines. Amongst the latter, the species Dunnicrinus aequalis is found preserved in biocalcarenites as…
Experimental study of boulder concentration effect on flow resistance in gravel bed channels
2021
Abstract Previous studies demonstrated that for open channel flows the power velocity profile can be integrated to obtain the flow resistance law. In this paper the relationship between Γ coefficient of the power velocity distribution, the channel slope and Froude number (Eq. (9) ) is firstly presented. Then the measurements carried out in a laboratory flume covered by hemispheric elements for two different hydraulic conditions (partially inundated and inundated) are used to calibrate this relationship. These elements are placed with a square arrangement and have a concentration range 4–64%. For the two investigated hydraulic conditions, this analysis demonstrates that the relationship to e…
Retrospective Analysis of Functional Pain among Professional Climbers
2022
Climbing became one of the official Olympic sports in 2020. The nociplastic pain mechanism is indicated as important in professional sports. Functional pain, which has not been examined in climbers until now, can be an example of nociplastic pain. This study aimed to determine functional pain locations in climbers according to gender and dominant climbing style. Climbers (n = 183) and healthy subjects (n = 160) completed an online survey focused on functional pain occurrence in the head, spine, and upper limbs. The logistic regression showed that climbing predisposes one to functional pain at: Gleno-humeral joint (odds ratio (OR): 3.06; area under the curve (AUC): 0.635), elbow (OR: 2.86; A…
Boulder dynamics in the Favignana Island coastal zone (Egadi Archipelago, Central Mediterranean)
2016
Boulders disjoined from platform edges or accumulated in the nearshore are frequently transported and deposited in the backshore as a consequence of tsunamis and high-magnitude storm waves. We investigate this process in the Favignana Island (Egadi Archipelago) coastal zone by integrating geological and morphological data with numerical hydrodynamic analysis and radiocarbon dating. Boulders and sockets are detected in proximity to the shorelines of Punta Faraglione and Punta Fanfalo, which are located in the NW and SE sectors of the Favignana Island, respectively. They are scattered on the rocky platform as isolated blocks or in small groups that, together, form a discontinuous berm. The la…
Effects of Boulder Arrangement on Flow Resistance Due to Macro-Scale Bed Roughness
2023
Flow resistance in gravel-bed channels is not only affected by the shape and size of the roughness elements, but also by their arrangement on the channel bed surface (position to flow streamlines, spacing between elements, and their protrusion from the channel bed). Many investigations proved that open channel flow resistance can be obtained by integrating the power velocity profile. For a macro-scale roughness condition, this study aims to investigate the effect of different boulder arrangements on flow resistance. First, for each arrangement, the equation relating Γ function of the power velocity profile, the Froude number, and the channel slope was calibrated using available measur…
Boulderoinnin lajianalyysi ja harjoittelu
2014
Boulderointi on kiipeilyn alalaji, jossa kiivettävät reitit ovat matalia ja kiipeily tapahtuu ilman köysivarmistusta. Lajilla on vahva ulko- ja seikkailuliikunnan maine, sillä boulderointia harrastetaan paljon luonnon kivillä; siirtolohkareilla ja kallioilla. Viimeisten 20 vuoden aikana boulderointi on vakiinnuttanut paikkansa kilpalajina kiipeilyn perinteisempien muotojen, lead- ja speed-kiipeilyn rinnalla. Boulderointi käsitetään usein nopeusvoimaa ja räjähtävää voimantuottoa vaativana lajina, verrattuna kestävyysominaisuuksia korostavaan lead-kiipeilyyn. Sormien koukistajalihasten nopea voimantuotto, käsivarren ja ylävartalon lihasten voimakestävyys sekä edullinen suhde ylävartalon voima…