Lavaflow volume and morphology from digitised contour maps : a case study at Mount Etna, Sicily
Cartography ; Italy ; Lavaflow ; Numerical model ; Sicilia ; Volcanic eruption ; Volcanism
The volume and morphology of a lavaflow-field can be measured by mapping and comparing the topography before and after lava emplacement. This paper explores the use of 1:25,000 scale digitised contour maps for mapping two lavaflows of diverse
This paper presents results of a detailed mapping and field study of the 1984 open-channel lavaflow. Identified surface-texture types are described as flow facies. Lavaflow dimensions are assessed by combining the pre- and post-flow topography
to get a realistic figure of the dimensions of the lavaflow. Video recordings are also used to draw conclusions about the development of the flow during eruption. Lavaflow models are then discussed in the light of topographic data and observations.
Mt Rouse, an exctint volcano south of Penshurst in W. Victoria was a source for copious lavaflows which followed pre-existing valleys and reached the coast 60 km to the south. Many typical features of drainage modifications are associated
with the lavaflows. Stony rises are widespread and it is deduced that a lava tube mechanism was in operation to produce such long flows. A new date for the volcano is 1,8 m.y., which is inconsistent with ages of about 0,3 m.y. reported from basalts near Port
Fairy. The Mt Rouse flows serve as a useful market for distinguishing Pleistocene from older volcanoes in this region. (E.C.F.B.).
the distributary tube system which supplies magma to the tumuli to branch vigorously. Large lava-inflation structures such as lava rises occur in areas where there were restrictions to branching.
Criteria for recognition of constructional silicic lavaflow surfaces
California ; Geochemistry ; Lava ; Lavaflow ; Stratigraphy ; United States ; Volcanism ; Weathering
Brief review of the literature on active and recent silicic lavaflow surface features and textural stratigraphy, then the AA. present criteria for field determination of constructional features. These criteria should aid in the identification
Radiocarbon studies of latest Pleistocene and Holocene lavaflows of the Snake River plain, Idaho: data, lessons, interpretation
Radiocarbon dating was applied to carbon bearing, charred eolian sediment from beneath the lavaflows. Twenty of the more than 60 lavaflows of the Crater of the Moon lava field have been dated| their ages range from about 15,000 to about 2000 yr
B.P. The ages permit assignment of the flows to eight distinct eruption periods with an average recurrence interval of about 2000 yr. The seven other latest Pleistocene-Holocene lava fields were emplaced in short eruptive bursts.
The aims of this study are 1) to examine erosion and sedimentation processes in the Paricutin cone and adjacent lava fields, in the first two decades after the eruption; 2) to identify revegetation processes and soil development; 3) to determine
In this paper, the AA. present a descriptive summary of tumuli from 3 geographically distinct volcanic fields dominated by pahoehoe lava fields. These 3 studied fields are geographically distinct, however the composition of the magma
and the volcanic settings as volcanic cone fields associated with extensive lava fields are common features among these fields. The young age and the semi-arid to arid climate provided excellent exposures to study lava surface features of the studied sites
The nature and rate of weathering by lichens on lavaflows on Lanzarote
Basalt ; Biogeochemistry ; Canary Islands ; Chemical erosion ; Climate ; Comparative study ; Eighteenth Century ; Hawaii ; Lavaflow ; Lichen ; Microstructure ; Model ; Weathering
Samples of lichen-covered and bare lava surfaces from Lanzarote, dating the 1730-1736 eruption, have been analysed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) to investigate the relative
Canary Islands ; Geomorphology ; Inverted relief ; Lavaflow ; Model ; Valley ; Volcanism
be applicable to numerous volcanic areas. Such valleys are developed as volcanic valleys undergo lateral expansion due to repeated alternations of processes: initial erosion of the gorges by streams, the burial of the gorges by lavaflows, and the inversion
Krisuvikureldar I. Aldur ogmundarhrauns og Midaldalagsins Age of the Ogmundarhraun lavaflow and the medieval tephra layer, Reykjanes Peninsula, Southwest Iceland
Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA
Here, the AA. report the results of hydrologic modeling of the flood wave representing one of these outburst floods, an event that occurred 165,000 yr ago with the failure of the Hyaloclastite Dam. The AA. used dam-failure and unsteady flow modeling
to estimate a peak discharge and flow hydrograph. Moreover, the Hyaloclastite outburst flood is the oldest documented Quaternary flood and one of the largest to have occurred in the continental USA.
The AA. report tectonic settings and geological features of Patagonia briefly and discuss some structural and geomorphological aspects that could be used to infer directions of magmatic flow of nearly horizontal lavas and to test stability of rock