Other related pages and images at this site...

Eruption96 page: includes photos and an account of the 96 eruption on Iceland
HOTSPOT data quality: comparison plot of HOTSPOT and GSN data quality

Project HOTSPOT:
A seismological study of the Iceland Hotspot.

The Princeton team:

Guust Nolet
W. Jason Morgan
Kristin Vogfjord
Richard M Allen.


This page is a brief introduction to Project HOTSPOT, a joint seismological study being conducted in Iceland by Princeton University, Durham University and Vedurdtofa Islands (The Icelandic Meteorological Office). The page outlines the goals of the project and the PASSCAL array instalation. We also include photos demonstrating why it is so much fun doing field work on that 'cold wet island'! Click on photos for full sized versions. The adjacent photo is a steam volcano found in many of the geothermal areas in Iceland. This one is at Krysuvik on the Reykjanes Peninsula and is approximatly 10 m high

Goals of the project

Iceland represents one of the most active hotspots on Earth, it produces an estimated 0.12 km3 of basalt every year - a rate only surpassed by Hawaii. Unlike Hawaii, however, Iceland is located on top of an ocean ridge system, and this interaction has produced a landmass that makes it possible to investigate the hotspot with land-based seismometers.

The seismological data will provide answers to our fundamental questions about the extent of the melt region, the nature of the interaction between the hotspot and the ridge, the cause of the topographic elevation that accompanies the hotspot (hotspot swell), which we think is the result of melt residue in the uppermost mantle, the thickness of the crust in Iceland, the present-day distribution of seismicity and volcanism on the island. We also plan to combine seismic results with gravity data to infer the density of the deeper regions of the hotspot.

The Array

The HOTSPOT project makes use of three arrays in Iceland. The HOTSPOT array itself, a mobile PASSCAL array of 30 instruments, the SIL network, a permanent array of 27 broadband and short period instruments opperated by Vedurstofa Islands, and 6 vertical component instruments operated by Raunvisindastofnun Haskolans (The University Science Institute, Iceland). The combined networks make a total of 63 instruments distributed evenly across Iceland, the station spacing is approximatly 50 km. Click on map to see enlarged version indicating the locations of the different sensor types. For more details about the array see our array instalation page.

Photos of installation

Click on photos for bigger images.

From left to right: Photo. 1. Princeton graduate student Richard Allen tests Reftek recorders and Guralp seismometers, on loan from PASSCAL. All equipment was tested on arrival in Reykjavik. Photo. 2. Kristin Vogfjord, Richard Allen (Princeton) and Palmi Erlendsson (Vedurstofa Islands) load a jeep with PASSCAL equipment and station building materials. Photo. 3. Once loaded the team sets off to find a suitable location for the station. Photo. 4. Jason Morgan (Princeton) wires up one of the Refteks in a shed against bedrock. Photo. 5. Guust Nolet (Princeton) and Palmi (Vedurstofa) check the equipment after installation in a village morgue.

Photos of other places we happened to pass by!

Click on photos for bigger images.

From left to right: Photo. 6. This is Gullfoss one of the most spectacular waterfalls in Iceland, it drains the melt waters from Langjokull and Hofsjokull. Photo. 7. is a close up, note the people for scale. Photo. 8. Strokkur erupts every 5 mins and is 20 m high. It sits next to Geysir (the original one) which now only erupts very infrequently, it used to erupt to a height of 80 m.

From left to right: Photo. 9. This ash cone is only 20 m in diameter and sits on the very tip of the Reykjanes Peninsula where the Mid-Atlantic Ridge comes ashore. The flow patterns are clearly seen in the basalt in the foreground. Photo. 10. The rift valley at Thingvellir. To the left one of the many fissures can be seen, the face on the side of the valley has rotated into the valley during extension. The dark strips on the far side are also the exposed faces of fissures. At the top of the picture (to the NW) is the Skjaldbreidur shield volcano, to the SE is a lake.

From left to right: Photo. 11. View across the top of the Westernfjords. This area is completely unreachable in the winter due to snow cover. Photo. 12. View from the same spot down Sudurfirdir. Photo. 13. Another spectacular waterfall. This one falls over a very clear example of columular jointing.

Recent Eruption Beneath Vatnajokull, Iceland

The most reacent eruption on Iceland closely followed a magnitude 5.5 event beneath Vatnajokull, the largest glacier in Europe. The eruption melted through hunderds of meters of ice to produce a spectacular plume of steam and ash. The melt waters did not escape immediatly building up in a sub glacial lake which finally burst a month later causing the largest flood in reacent history. For more information and pictures from the eruption, from various sources, see eruption96. All events associated with this eruption were recorded on the HOTSPOT network.

last updated 3/1/1997 - RMA
© Richard M Allen

This page is maintained by Richard M Allen, to Richards homepage