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After we dealt with some faults in Greece, let’s move to Spain. The Ventas de Zafarraya Fault (VZF) west of the Granada basin (36.96° N, 4.14°W) has a beautiful morphologic expression and an exciting history. The fault bounds the Zafarraya polje to the south, with Quaternary sediments to the north (hanging wall) and limestones of the Internal Subbetics in the footwall. more

This day’s Centerfault is the Sparta Fault in southern Greece (37.1°N 23.3°E). Being situated on the Peloponessus, the fault marks one of the most prominent geomorphological features of the peninsula. It is famous for the historical 464 BC earthquake that destroyed ancient Sparta. However,  the days of Spartian glory ended much later after a severe military defeat in the battle of Leuctra in 371 BC, Sparta never fully recovered. more

Following Tomas post let’s stay a little longer on the Corinth Canal. The 6 km long famous Corinth Canal despite being an amazing feat of engineering, since it was constructed 120 year ago, it’s also a geology field trip favourite because it is basically a MEGA TRENCH.

More than 40 faults can be identified some of them offsetting the entire sedimentary column, whereas others are confined within the lower sediments. Therefore, this photo shows a very nice example of an active and inactive fault within the same outcrop. You can rarely see something like that and this is a unique site where everybody can see and comprehend it.

View of an active and inactive fault

Faults also die.

It shows also that faults die. This is very important because there are numerous faults in the crust, however the majority of them are inactive (e.g. can not give an earthquake today, but they did so in the past). So for earthquake geologists their first major goal is to identify which of the faults they map are active (e.g. can generate earthquakes today and represent seismic sources).

Faults also die.

Some days ago a new paper on the paleoseismicity of the Dead Sea area during the late Holocene has been published in JGR. Kagan et al, 2011 investigated two new study sites in the northern and southern parts of the Dead Sea Basin and compared the seismites found there with the information of the Ein Gedi core presented by Migowski et al., 2004.

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It’s not easy to prepare weekly Friday links when you are abroad, this is what I had to realize in April. However, I will try to post a natural beauty each Wednesday in the future, the Wednesday Centerfaults and Centerfolds.

Today, I start with the Kaparelli Fault in Greece (38.22°N, 23.23°E). This beautiful limestone fault scarp is more than 2.5 km long and up to 5 m high. The fault was activated during the 1981 Corinth earthquakes. more

Some days ago, a great new paper was published on the investigation of soft-sediment deformation in paleoseismology: “Alsop & Marco 2011: Soft-Sediment deformation within seismogenic slumps of the Dead Sea Basin. Journal of Structural Geology 33 (2011) 433-457.” The authors investigated the most beautiful seismites I’ve ever seen and generated different scenarios for their interpretation with respect to paleoseismic events. more

Now the EGU2011 in Vienna is over. Thousands of scientists have attended the meeting and more than 13,000 abstratcs were presented. Approx. 20,000 portions of Gulasz and 100,000 Wiener Schnitzels were served, hektoliters of wine and beer went down the throats of thirsty scientists. Some people say the EGU contributes with 10% to the income of Vienna’s bartenders. Several contributions dealt with paleoseismology, paleoseismicity, archeoseismology and paleotsunamis especially on Monday and Friday. more

The Japan earthquake and tsunami have hit Japan harder than we could have imagined. Thousands are still missing, the death toll climbs and climbs, a nuclear disaster might happen or already happened, depending on who you ask, and the economical damages are incredibly high. Not only Japan was affected, but other countries as well feel the effects. Germany, for example, shut down seven of it’s oldest nuclear power plants and there’s a big debate on earthquakes and risks. The Geoblogosphere is still discussing lessons, estimations and consequences, and so are the official media. Here are some reports and opinions you should not miss. more

The Japan M9.0 earthquake and the following tsunami are well documented by videos, photographs, sea-level measurements, seismograms etc. But how do we recognize such huge events if they happened some thousands of years ago? If there’s no historical report we would use earthquake environmental effects (EEE) for characterizing the earthquake and paleoseismicity. Let’s look what would be left from a 5000 year old earthquake and tsunami. more

An earthquake with a magnitude of Mw9.0 has occured 130 km east of Honshu, Japan in a depth of ~25 km. This had been the fourth or fifth strongest earthquake to be recorded by instrumental seismology. The quake caused significant destruction to the Honshu Island and triggered a tsunami that  destroyed a number of harbours. In some places (Sendai), tsunami heights were reported to exceed 10 m. A tsunami warning has been released for wide parts of the Pacific, but in Hawaii only 1 m was observed, therefore the warnings for the US West Coast have been lowered. more