Volcanically active islands abound in the tropical Pacific and harbor complex coral communities. Whereas lava streams and deep ash deposits are well-known to devastate coral communities through burial and smothering, little is known about the effect of moderate amounts of small particulate ash deposits on reef communities. Volcanic ash contains a diversity of chemical compounds that can induce ...

Various kinds of soils can be formed from volcanic ash depending on the individual set of soil forming factors at different sites. Among these soils, Andisols or Andosols show unique properties mostly due to abundant noncrystalline materials such as allophane, imogolite, Al-humus complexes, ferrihydrite and so on. Highly porous structures made of aggregated noncrystalline Andisol materials have...

We present a polynomial chaos based minimum variance formulation to solve inverse problems. The utility of the proposed approach is evaluated by considering the ash transport problem arising due to volcanic eruption. Volcanic ash advisory centers generally makes use of mathematical models for column eruption and advection and diffusion of ash cloud in atmosphere. These models require input data...

FALL3D is a 3-D time-dependent Eulerian model for the transport and deposition of volcanic ashes and lapilli. The model solves the advection–diffusion–sedimentation (ADS) equation on a structured terrain-following grid using a second-order finite differences (FD) explicit scheme. Different parameterizations for the eddy diffusivity tensor and for the particle terminal settling velocities can be...

[1] Sediment gravity cores collected from the Pacific seafloor offshore Central America contain numerous distal ash layers from plinian-type eruptions at the Central American Volcanic Arc dating back to more than 200 ka. In part 1 of this contribution we have correlated many of those ash layers between cores and with 26 tephras on land. The marine ash layers cover areas of up to 10 km in the Pa...

Large-scale volcanic eruptions produce fine ash (< 200 μm) which has a long atmospheric residence time (1 hour or more) and can be transported great distances from the volcanic source, thus, becoming a hazard to aircraft and public health. Ash particles have irregular shapes, so data on particle shape, size, and terminal velocities are needed to understand how the irregular-shaped particles aff...

Carol Stewart,*3 Lino Pizzolon,4 Thomas Wilson,1 Graham Leonard,I David Dewar,1 David Johnston,# and Shane Cronin33 7Private Consultant, Brooklyn, Wellington, New Zealand 8National University of Patagonia, Esquel, Argentina 6University of Canterbury, Christchurch, New Zealand IGNS Science, Avalon, Lower Hutt, New Zealand #GNS Science/Massey University, Avalon, Lower Hutt, New Zealand 77Massey U...

In this paper we will present early work on using a DDDAS based approach to the construction of probabilistic estimates of volcanic ash transport and dispersal. Our primary modeling tools will be a combination of a plume eruption model BENT and the ash transport model PUFF. Data from satellite imagery, observation of vent parameters and windfields will drive our simulations. We will use uncerta...

zeolites due to their structures can be used as molecular sieves for purification of materials and solutions. zeolites with phi and sod structure are so common and applicable for this purpose. hydroxy sodalite and phillipsite are the more abundant members of zeolites which display good selectivity for very small molecules and some ions such as sr, pb, zn, cu and rb. there is not any pure natura...