Geology

Have you noticed that whenever a [natural]disaster strikes we quickly look around to find a guilty party? The first place we look is among politicians. The politicians are not to blame for the natural disaster of course, at least not the nature part of it. The dimensions of the disaster can however fairly easily be tracked back to humans, more specifically to the political leadership who are responsible for managing both natural and human resources. Natural hazards becomes huge disasters if politicians are not taking early warning seriously. The above image shows Sendai after the Tohoku-oki…

At the Top of the World.The massive 9.0 M earthquake at Tohoku, Japan, 11. March 2011 literally shook the entire planet. The signals were read even at the top of the world, close to the north pole. Read on to learn about earthquake and tsunami observations in general before you take a look at the unique earthquake recordings from the high-north. by Bente Lilja Bye and Ove Christian Dahl Omang Ny-Ålesund Geodetic Laboratory, Svalbard, Norway. Credit: Ove Christian Dahl Omang After the 2004 Indian Ocean tsunami the international community stepped up its efforts on developing and building early…

Japan Earthquake Increases Flood Risk In Fukushima During the 2011 Tohoku Earthquake in Japan, the ground level sank along the coast near Onahama Port,  Fukushima Prefecture. This has caused recent average tide levels to rise by about 40cm. A tide level recording from Onahama Port shows the tide level fluctuations at the time of the quake and the subsquent increase in tide levels. Tide level at Onahama, Fukushima Prefecture.image source: JMA Onahama Port is shown on the map below. Fukushima Prefecture map.image source: http://www.pref.fukushima.jp/port/e/ Implications of higher sea…

What do the Ansei-Nankai and Ansei-Tokai earthquakes of 1854 have in common with the 1944-1946 Tononkai and Nankai earthquakes in Japan?   They each suffered massive aftershocks shortly thereafter.    The Ansei-Nankai and Ansei-Tokai earthquakes were 8.4 magnitude and only 31 hours apart.  Worse, the aftershocks were nearly as bad. And the same scenario could apply this time, says UC Davis seismologist John Rundle, and Tokyo is at the most risk.  Friday's magnitude 9.0 temblor has been followed by hundreds ofpowerful aftershocks that have migrated southwards.…

Earthquakes are big news due to the devastating 8.9 magnitude earthquake that struck Japan on Friday.   As a result, some are curious about the worst earthquakes and resulting tsunamis we know about.   Prior to the 20th century, methods for measuring were unreliable. Researchers say a new tool may more about earthquakes of the ancient past and even help predict earthquakes of the future.  Prof. Shmuel Marco of Tel Aviv University's Department of Geophysics and Planetary Sciences in the Raymond and Beverly Sackler Faculty of Exact Sciences and his colleagues have created a…

The 8.9 magnitude earthquake off the coast of Japan was a devastating event and did unknown amounts of damage.    There is risk of fire, water shortages, power outages and radiation leaks, not to mention 1,000 dead.   (To separate mass media hype from fact, see Patrick Lockerby's comprehensive and frequently updated Japan's Nuclear Emergency - The Straight Goods and also Japan Quake - Media Up To Mischief) In the context of all that it may seem cavalier to state that if it has to happen, at least it happened in Japan, but that's the case; it is impossible to gauge how many…

Astrologers are feeling pretty good today.   Because it's made up and not science, anything happening anywhere near a date they predict can be attribution, so talk of a 'supermoon' - a new or full moon at 90% of its closest perigee - followed by an earthquake in Japan makes them seem prescient. Well, are they?   The supermoon which will occur March 19 will be at its closest to Earth in elliptical orbit (lunar perigee) and closer to Earth than it has been in 18 years.    How close is that?  Only about 2 degrees so unless astrologers have the kind of measurement…

The theme of the latest Accretionary Wedge (a carnival of geoblogs) is “Throw me your ‘favorite geologic picture’ mister”, so here is mine: Despite my relatively short career as a geologist, it was a hard choice.  There was a spectacular fault outcrop in Arkitsa, Greece; some impossible-looking resistant beds sticking straight out of the forest near Benés in the Catalan Pyrenees; and the classic 'ripples on a vertical surface' to illustrate tectonic forces, also in the Catalan Pyrenees.  However, I decided on this photo in the end, mainly because now I am a proper volcanologist I…

Early in the formation of the Earth, some forms of the element chromium separated and disappeared deep into the planet's core, according to a new study in Science. The team studied a class of meteorites called chondrites, which are leftovers from the formation of the solar system more than 4.5 billion years ago.    By making very accurate measurements of chromium isotopes in the meteorites compared to Earth rocks and comparing them to theoretical predictions, the researchers were able to show for the first time that lighter isotopes of chromium preferentially go into the core.…

Two hundred million years ago, Washington was two large islands, bits of continent on the move westward, eventually bumping up against the North American continent and calling it home. Even with their new fixed address, the shifting continues; the more extreme movement has subsided laterally and continues vertically. The upthrusting of plates continues to move our mountain ranges skyward – the path of least resistance. This dynamic movement has created the landscape we see today and helped form the fossil record that tells much of Washington’s relatively recent history – the past 50 million…