pulses, which are the most characteristic feature of near-fault strong-
motion, scale with key parameters of the specific barrier model and may effectively be simulated using
a phenomenological model. The key model parameter, the local stress drop, has been inferred from
Icelandic strong-motion data. The variations in site conditions of the recording sites have been
approximated
/media/norsem/norsem_benni.pdf
–conduit model for subglacial water flow was used to simulate the
jökulhlaup. The model was forced with the estimated outflow from the subglacial lake.
The simulations were not successful as a realistic subglacial pressure field could not
be obtained for a reasonable fit of the jökulhlaup discharge at the glacier terminus.
This indicates that the physical basis of the model is insufficient to provide
/media/vedurstofan/utgafa/skyrslur/2009/VI_2009_006_tt.pdf
the moment release dropped by a factor of 100 - 200 in the first weeks after the onset of the eruption. This drop is expected, as the eruption released pressure from the dyke. In the following weeks, activity drops further by a factor of 50 - 100, but remains rather stable at around 5E12 Nm during the last three months. The total decay of moment release in the dyke has dropped by a factor of about
/earthquakes-and-volcanism/articles/nr/3083
measurements at Keflavik airport, on loan from UK,
arrives in October.
Ash concentration measurements from a piston plane in cooperation with
Icelandair.
Portable radiosonde station for atmospheric conditions at eruption site –
on loan from UK.
SO2 measurements at eruption site in cooperation with NOVAC
(Differential Optical Absorbtion Spectrometer, DOAS).
NAME dispersion model will be made
/media/vedurstofan/myndasafn/Eyjafjallajokull_SK_20101214_1.pdf
for the time period 2001–2009, obtained from the permanent SIL network, were analysed to
study stress changes associated with the main shocks. Results reveal a coseismic counter-clockwise
rotation of the maximum horizontal stress of 11 ± 10° (95 per cent confidence level) in the main rupture
region. From previous fault models obtained by inversion of geodetic data, we estimate a stress drop/media/norsem/norsem_martin.pdf
6University of Washington,
Seattle, WA 98195, USA. 7NOAA Geophysical Fluid
Dynamics Laboratory, Princeton, NJ 08540, USA.
*Author for correspondence. E-mail: cmilly@usgs.gov.
An uncertain future challenges water planners.
Published by AAAS
on July 12, 201
1
www.sciencemag.or
g
Downloaded from
1 FEBRUARY 2008 VOL 319 SCIENCE www.sciencemag.org574
POLICYFORUM
combined with opera-
tions
/media/loftslag/Milly_etal-2008-Stationarity-dead-Science.pdf
flood will commence in the coming weeks-months, the water levels under the ice will drop yet there will not be an eruption (as in 2010).A glacial flood will commence in the coming weeks-months, the water levels under the ice will drop and Grímsvötn will erupt. It is most likely that the eruption will be small to medium-sized with significant volcanic tephra fall on Vatnajökull glacier and little
/about-imo/news/the-civil-protection-scientific-advisory-board-meets-to-discuss-the-status-of-grimsvotn
) ................................................................ 46
3.3.3 The Hengill area and the South Iceland seismic zone (boxes G-M) ............ 48
3.3.4 Active faults in 2000 .................................................................................... 56
3.4 Depth distribution, stress drop and thickness of the brittle crust .......................... 58
4 Discussion
/media/vedurstofan/utgafa/skyrslur/2010/2010_003rs.pdf
the free parameters k and K is the constant on the right hand side of (4). For a constant
stress drop of ∆σ= 1 MPa and a fit of model (1) to the PGV data with g = 0.5 the parameter K is
approximately 1.5. Informally speaking, we can say that the transition between near-field and
far-field takes place close to 1.5 fault radii away from the epicenter.
We now show why the parameter g should fulfill
/media/vedurstofan/utgafa/skyrslur/2009/VI_2009_012.pdf