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  • Two different volcanic ash-falls of Allerod age in high Belgium
  • Applying the same method to different ash layers, two volcanic ash-falls of Allerod age are distinguished: the Brackvenn ash-fall (14C age: 10 830 45 a B.P.) and the Konnerzvenn ash-fall (14C age: 11 030 160 a B.P.). (LW).
  • How liverworts build hanging gardens from volcanic ash in Costa Rica
  • Biogeography ; Costa Rica ; Micromorphology ; Plant colonization ; Vegetation ; Volcanic ash ; Volcano
  • Biogéographie ; Cendre volcanique ; Colonisation végétale ; Costa Rica ; Micromorphologie ; Plante pionnière ; Volcan ; Végétation
  • The AA. report how a pioneer liverwort, Nardia succulenta, stimulates accretion of volcanic ash, creating layers adhering to vertical bare cliffs and bridging fresh volcanic boulders, as well as creating habits that probably favour the liverworts
  • New radiocarbon dates for the Vedde Ash and the Saksunarvatn Ash from Western Norway
  • C 14 dating ; Dendrochronology ; Geochemistry ; Geochronology ; Holocene ; Norway ; Quaternary ; Stratigraphy ; Tephrochronology ; Volcanic ash
  • The Vedde Ash Bed (mid-Younger Dryas) and the Saksunarvatn Ash (early Holocene) are important regional stratigraphic event markers in the North Atlantic, the Norwegian Sea, and the adjacent land area.It is thus essential to date them as precisely
  • A volcanic ash generated by explosions where ignimbrite entered the sea
  • A remarkably widely dispersed and crystal-rich volcanic ash-fall deposit is described, which resulted from immense explosions generated in the littoral zone in New Zealand where a major rhyolitic ignimbrite flowed into the sea. This partially
  • Greetings from Iceland. Ash-falls and volcanic aerosols in Scandinavia
  • A brief account of ash-falls and aerosols from historical volcanic eruptions in Iceland that have affected Scandinavia is given with special reference to the noxious effects of aerosols from the Lakagigar eruption of 1783 registered in contemporary
  • Toba ash on the Indian subcontinent and its implications for correlation of Late Pleistocene alluvium
  • Geochemistry ; India ; Marine sediment ; Pleistocene ; Pyroclastic ; Quaternary ; Stratigraphic correlation ; Stratigraphy ; Volcanic ash
  • The Youngest Toba Ash (Ca. 74,000 yr B.P.) occurs extensively in the Indian subcontinent. The reworked ash samples are closely similar in their bulk chemical composition, REE signature, and bubble-wall shard morphology to those from the Toba caldera
  • and deep-sea cores from the Bay of Bengal and Indian Ocean. The Toba ash thus can be used as an event marker for regional and global Quaternary correlation.
  • Characteristics and possible source of a 1 479 A.D. volcanic ash layer in a Greenland ice core
  • Atmospheric circulation ; Climatic variation ; Geochemistry ; Global change ; Greenland ; Ice ; Ice core ; Palaeogeography ; Volcanic ash ; Volcanic eruption
  • This study shows that ice cores contain valuable information of past eruptions, even if the identify of the source volcano or eruption cannot be specified. Such studies may provide important information regarding the link between major volcanic
  • Erodibility and runoff-infiltration characteristics of volcanic ash soils along an altitudinal climosequence in the Ecuadorian Andes
  • Andes ; Ecuador ; Erodibility ; Land use ; Pedogenesis ; Rainfall simulation ; Runoff ; Slope gradient ; Soil erosion ; Soil properties ; Volcanic soil
  • The aim of this research was to study erodibility and runoff-infiltration characteristics of volcanic ash soils of a climate-induced altitudinal Entisols-Inceptisols-Andisols sequence on the slopes of a volcanic peak in the Andes of northern Ecuador
  • Post-1883 ash fall on Panjang and Sertung and its ecological impact
  • Biogeography ; Cluster analysis ; Geochemistry ; Indonesia ; Island ; Multivariate analysis ; Pyroclastic ; Soil ; Soil properties ; Stratigraphy ; Vegetation dynamics ; Volcanic ash ; Volcanic eruption ; Volcanism
  • This paper describes the post-1883 history of volcanic disturbance to the islands Panjang and Sertung, within the Krakatau group, Indonesia. The results of analyses of chemical, physical and particularly of mineral magnetic properties are presented
  • , with the aim of assessing spatial variation in ash fall history across Panjang and Sertung. Most sites on both islands showed evidence of a number of distinct ash-falls in both the early 1930s and 1952/53 periods, of a highly disruptive nature. Sites nearest
  • the Anak Krakatau typically contained evidence of the largest number of different ashes. The implications of these data for the biogeography of the group are briefly discussed.
  • Mount Churchill, Alaska: source of the late Holocene White River Ash
  • Alaska ; Geochemistry ; Holocene ; Mineralogy ; Palaeogeography ; Trace-element ; Volcanic ash ; Volcanism
  • Revue des tentatives d'identification de la source du volumineux dépôt de cendres de White River Ash et présentation des nouvelles données physiques et chimiques démontrant que le Mont Churchill est un volcan holocène à l'origine de ce dépôt de
  • Observations of volcanic ash clouds in the 10-12 m window using AVHRR/2 data in Special issue : Applications of AVHRR data.
  • Holocene yardangs in volcanic terrains in the southern Andes, Argentina
  • Aeolian features ; Andes ; Argentina ; Arid area ; Basalt ; Holocene ; Mountain ; Semi-arid area ; Volcanic ash ; Wind erosion
  • and Holocene lava flow events in the area. The yardang development is explained by the strong unidirectional winds, the poor vegetational cover due to the aridity of the region, the available quartz sand and volcanic ash particles as abrasive agents
  • The aim of this paper is to report on yardangs in the Payun Matru Volcanic Field, a semiarid area east of the southern Andes mountains, and to analyse the geomorphic fators for their formation, and their relationship to the upper Pleistocene
  • , and the volcanic lithology texture and flow structure.
  • A Younger Dryas ash bed in western Norway, and its possible correlations with tephra in cores from the Norwegian Sea and the North Atlantic
  • ; Sédimentologie ; Téphrochronologie ; Vedde Ash Bed
  • A bed of volcanic ash up to 23 cm thick is found in lacustrine and marine sediments in western Norway. It is formally named the Vedde Ash Bed, and its age is approximately 10,600 yr B.P., i.e., mid-Younger Dryas. The bed consists of pure glass
  • having a bimodal basaltic and rhyolitic composition. The geochemistry of the glass shards suggests an Icelandic source. By means of stratigraphic position and geochemistry, the ash is correlated with ash zones found in cores from the continental shelf
  • Late Quaternary volcanic ash in the peatlands of central Alberta
  • The distribution of Laacher See ash West of the Eifel region
  • Volcanic grain percentages in heavy-mineral concentrates of local colluvial deposits in Luxembourg and surrounding areas have been used to trace the dispersal of an ash deposit of Allerod age characterised by an association of brown amphibole
  • , pyroxene and sphene. Remnants of the ash fall were detected at distances of more than 300km southwest of the Laacher See eruption centre. As Allerod ashes previously have been found at similar distances east of this centre, it is evident that the dominant
  • wind direction during this geological interstade cannot be reconstructed from the distribution of ashes produced by short-lived eruptions. (AIS).
  • A study on neogene volcanic landforms of the middle Tanlu fault belt
  • Caldera ; Cenozoic ; China ; Erosion ; Fault ; Lava ; Neogene ; Shandong ; Typology ; Volcanic ash ; Volcanism
  • This paper divides the volcanic landforms into 4 grades according to formation, morphology, annd ingredient of matter. Lava cones are divided into 2 types based on the force of top-support and the fluid form of magma : the arc-projecting type
  • and spring-spilling type. Furthermore, the courses of development of volcanic landforms are divided into 3 stages according to the form and strength of volcanic activities.
  • Atmospheric aerosol loading and transport due to the 1783-84 laki eruption in Iceland, interpreted from ash particles and acidity in the GISP2 ice core
  • Aerosol ; Atmospheric circulation ; Climatic variability ; Geochemistry ; Greenland ; Ice core ; Iceland ; Isotope analysis ; Volcanic ash ; Volcanic eruption
  • By using major ion, microparticle, and stable-isotope data obtained from ice cores, it is possible to assess the degree of atmospheric loading and potential climatic importance of major volcanic eruptions that occured prior to 1880. The AA. have
  • identified both silicate ash particle and sulfuric acid fallout from the 1783 Laki eruption in Iceland in the Geenland Ice Sheet Project 2 (GISP2) firn and ice core collected in 1989. The AA. use this information, coupled with available information
  • Seismipedoturbations in volcanic soils in North-Eastern Ecuador
  • Earthquake ; Ecuador ; Geochemistry ; Landslide ; Mass movement ; Pedogenesis ; Soil ; Soil properties ; Volcanic soil ; Volcanism
  • On 5 March 1987 two earth tremors caused topsoil and turf overturning, cracks in the ash mantle, and probably also cracks in soil profiles. In seismically active regions such episodic events may substantially influence soil profile development.
  • Properties of the new volcanic substrate of Mt. Usu with regards to natural revegetation
  • The 1977-78 eruptions of Mt. Usu deposited a thick ash-pumice mantle on the summit caldera. Natural revegetation occurred but not in a uniform manner.
  • Effects of agricultural practices on the hydrodynamics of a deep tilled hardened volcanic ash-soil (Cangahua) in Ecuador
  • Agricultural practice ; Agropedology ; Ecuador ; Rainfall simulation ; Rill wash ; Soil erosion ; Soil properties ; Volcanic soil ; Water erosion
  • This study was undertaken on an experimental farm in proximity to the city of Tumbaco, near the Ilaló volcano, 20 km east of Quito. The material derived from the fragmentation of the hardened volcanic ashes is stongly prone to pluvial erosion