Search results for "Aeolian processes"
showing 10 items of 70 documents
Late Pleistocene to Early Holocene natural and human influenced sediment dynamics and soil formation in a 0-order catchment in SW-Germany (Palatinate…
2013
This paper presents the dynamics of sedimentation processes and soil development of a steeply sloping 0-order catchment in the sandy Lower Bunter of the south-western mid-range mountains in the Palatinate Forest (Germany) during the transition period from the Late Glacial to the Early Holocene. Field investigations, chemical, physical, micromorphological and anthracological analyses revealed a complex palaeosol-sediment sequence along the thalweg of a dry valley, where a significant amount of the sediment from the adjacent slopes had been captured. The deposition of aeolian sands in the lowermost sediment layer took place in the early Late Glacial. The subsequent sediments were deposited by…
GC and GC-–MS Analysis of Volatile Compounds From Ballota nigra subsp. uncinata Collected in Aeolian Islands, Sicily (Southern Italy)
2020
In the present study, the chemical composition of the essential oils from aerial parts of Ballota nigra subsp. uncinata (Bég.) Patzak collected in Sicily was evaluated by gas chromatography (GC) and GC-mass spectrometry. The main components of the oil were ( E)-phytol (20.0%), α-pinene (9.0%), hexahydrofarnesyl acetone (5.7%), and α-selinene (5.1%). Cluster analysis of the essential oil compositions of all the taxa belonging to B. nigra s.l. group was performed.
Pleistocene and Holocene aeolian sediments of different location and geological history: A new insight from rounding and frosting of quartz grains
2014
Abstract Rounding and frosting of quartz grains in aeolian sediments of the known stratigraphic position and unique geological setting was explored in Finnish, Estonian, Latvian, and Polish localities and in Fuerteventura Island. The aim of the study is to characterize the variability of the spatial pattern of rounding and frosting of quartz grains in the sandy (0.5–0.8 mm) fraction and to evaluate the factors influencing it. The relationships between rounded and non-abraded, as well as matt- and shiny-type quartz grains were calculated for 159 samples and evaluated against the aeolian subenvironment, substratum and presumed age of the locations. The obtained relations do not confirm meridi…
Long-Range Ecogeomorphic Processes
2013
Processes operating at larger spatial scales interact with those operating at smaller scales (discussed in the previous chapter) to produce spatial patterns in drylands. Hydrological processes operating at the catchment scale, the effects of grazing, fire, water and wind erosion are considered separately and in relation to their interactions with propagules and plants. The chapter concludes with a consideration of the extent to which feedbacks are central to pattern formation.
Seasonal variation of air kerma in the "Vulcano Porto" area (Aeolian Islands, Italy).
2001
Abstract Air kerma was measured in the “Vulcano Porto” area of the Vulcano Island, belonging to the Aeolian Islands, in the Mediterranean Sea. Measurements were carried out using thermoluminescence dosimeters. The relationship between observed dose values and source lithology has been assessed. Data show a seasonal variation due to weather conditions but also probably related to features of the soils, making the variation more evident.
Environmental radioactivity at Stromboli (Aeolian Islands)
2002
HPGe gamma spectrometry, thermoluminescence dosimetry, X-ray diffractometry and fluorescence techniques have been used to analyze the natural radionuclides content of soil and rock samples, air kerma and geochemical features on the island of Stromboli, belonging to the Aeolian Islands, in the Mediterranean Sea. The 214Bi, 238Ac, and 40K contents obtained are in agreement with the magmatic evolution of the rock formation, as shown by the correlations between radionuclide and chemical elements abundacies, depending on the various magmatic differentiation mechanisms. Correlations between radiometric, lithological and geochemical data have been assessed in order to obtain some hints on the geoc…
Eolian sedimentation in central European Auel dry maar from 60 to 13 ka
2021
AbstractThe climate in central Europe during the last 60 ka is characterized by rapid temperature and moisture changes and strong cold periods (Heinrich events). All these variations are preserved in sediments of marine and also some terrestrial archives. Here we present a continuous, terrestrial sediment record with almost all Greenland stadials and Heinrich events between 60 and 13 ka visible from carbonate roundness of the Eifel Laminated Sediment Archive Dust Stack-20 and CaCO3 data for central Europe. The carbonate roundness data show almost all stadials between 60 and 13 ka. CaCO3 data show a general transport system change with the beginning of Heinrich event 3. Since there are no ca…
Shortage of Sediments in the Maspalomas Dune Field (Gran Canaria, Canary Islands) Deduced from Analysis of Aerial Photographs, Foraminiferal Content,…
2007
Abstract The Maspalomas dune field and adjacent beaches are the most extensive coastal sedimentary environment on the island of Gran Canaria. This area is very important from both a natural and an economic perspective. The analysis of aerial photographs and satellite images from recent decades does not show important shoreline changes for the El Ingles and Maspalomas beaches, which can be considered, consequently, in a state of equilibrium. However, the Maspalomas dune field presents several modifications, such as aeolian corridors associated with beach kiosks, a significant reduction in thickness of the aeolian deposits, and an increase of deflation areas in the underlying substratum. All …
Soil gas prospection of He,222Rn and CO2: Vulcano Porto area, Aeolian Islands, Italy
1997
Abstract In March 1994, soil gases were sampled in the area of Vulcano Porto, on the island of Vulcano, using a grid of about 200 points/km 2 . Analysed gases were CO 2 , He and 222 Rn and, over a smaller area, H 2 S. Some of the samples were also analysed for the isotope composition of CO 2 C. Three anomalous CO 2 degassing areas were identified: Grotta dei Palizzi, the area near the Telephone Exchange, and the area near the beach fumaroles. The behaviour of He and 222 Rn is different in these 3 areas. The concentration of He is much lower than that of atmospheric He (down to −3950 ppb) in the isthmus, and only in the area near Grotta dei Palizzi does it have values significantly higher th…
OSL dating of sediments from the Gobi Desert, Southern Mongolia
2010
Abstract The present study focuses on the chronological relationship between alternating dune sand and silty water-lain sediments in the central part of the Khongoryn Els dune field in the Gobi Desert, Southern Mongolia. The 23 m high section evolved from the construction of a natural dam by west–east moving sand dunes and fluvial inundation by a river system from the mountain ranges in the south. To resolve the chronology of events, optically stimulated luminescence (OSL) dating was applied and from sedimentological and geochemical analysis the depositional processes could be characterised. Quartz OSL dating of these sediments is hindered by feldspar contamination. Thus, dating of coarse-g…