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I am not sure if the geoscience community has realized that astronomy made three steps forward recently, so I’ll start out of topic. Three major astronomical problems have been solved! Really! more

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

Because of the recent news, these Friday links will deal with earthquake prediction. As in the L’Aquila case and in the Judgment Day “prophecy”, a reliable prediction is not possible until now. Repeat: NOT POSSIBLE! more

This week´s Centerfault is the famous Arkitsa Fault in Greece (38.43°N, 23.00°E). Along this about 500 m long and locally more than 40 m high excavated limestone fault plane within Mesozoic platform carbonates are uplifted against Pliocene-Quaternary sediments.

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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.

Today’s Friday links concentrate on tsunamis. Recently, Pure and Applied Geophysics came up with quite a lot of tsunami papers, and I am sure that this decision was made before the Japan tsunami happened. Some papers fur sure are interesting for analysing past tsunamis and earthquake environmental effects.

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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

A strong aftershock has rocked Japan on 11 April. USGS reported a magnitude of 6.7, while EMSC estimated M6.6. A tsunami warning has been released by the Japan Meteorological Agency for the eastern coast of Japan’s Honshu Island. UPDATE 13:06 MEST: The Tsunami warning has been cancelled. 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