Earthquake triggers research in Pacific Ocean

The Integrated Ocean Drilling Program (IODP) is an international marine research program that explores Earth's history and structure recorded in seafloor sediments and rocks, and monitors subseafloor environments. IODP builds upon the earlier successes of the Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP), which revolutionized our view of Earth history and global processes through ocean basin exploration.

Geology.com publishes a story about the Costa Rica Seismogenesis Project (CRISP) expedition carried out by the scientific drilling vessel JOIDES Resolution, and the nearly 1,500 m of sediments collected from the ocean floor off the coast of Costa Rica, revealing records of some two million years of tectonic activity along a seismic plate boundary.

You can find more on this story in the original sources:

http://geology.com/press-release/pacific-earthquake-triggers/
http://iodp.org/index.php?option=com_content&task=view&id=577&Itemid=1237

The CRISP research site is located 174 km (108 miles) off Costa Rica. IODP image.

Core

http://xkcd.com/913/

DRT2011 in Oviedo (and cider, chorizo, fabada...)

As I wrote some months ago, this year's DRT meeting will take place at the end of August/beginning of September in Oviedo, capital city of Asturias (Spain). University of Oviedo organise this time the biannual reunion dedicated to deformation processes at different scales and, besides a great meeting with very interesting keynote talks, they also offer a pre- and post- fieldtrips that you shouldn't miss.

From today, July 7th to 31st, the normal registration fee is just 200€, and if you decide, and you should, register for the fieldtrips and the conference dinner, the total amount would be 595€.
You can find more information in their website: http://www.geol.uniovi.es/drt2011/Home.html
Not convinced by the talks, fieldtrips to the Variscan foreland fold and thrust belt and to the hinterland of the orogen? Not convinced by the value for money of the conference?

Then, perhaps you should go in order to try sidra (Asturian cider),

the chorizo,

and fabada! (and many, many, many more dishes that you will love!)
Not yet convinced??? Then take a look to the pictures of the YORSGET meeting organised also by the Department of Geology of University of Oviedo: http://www.unioviedo.es/YORSGET/FOTOS-CONGRESO/PHOTOGALLERIES.htm

(And yes, I miss my homeland and I will be there :-) )

:-)

Louis Neel Medal to Ernie Rutter

Prof. Ernie Rutter, from the school of Earth, atmospheric and environmental sciences of the University of Manchester, has been awarded with the Louis Néel Medal of the EGU for "his major experimental and field contributions to our fundamental understanding of the deformation behaviour of the Earth's lithosphere. In particular, his systematic laboratory studies have led to a greatly improved understanding of natural rock deformation".

The Louis Néel Medal, named after the French physicist (awarded a Nobel Prize in 1970),  has been established by the Division on Magnetism, Palaeomagnetism and Rock Physics. This medal is reserved for individuals in recognition of outstanding achievements in rock magnetism and rock physics and geomaterials.

The full story, here: http://www.egu.eu/awards-medals/awards-and-medals/award/louis-neel/teng-fong-wong0.html

Prof. Rutter: http://www.seaes.manchester.ac.uk/aboutus/staff/staffprofile.php?id=52

Thrust duplexes in Devon and Galicia

I came across the website of Jim Talbot thanks to a friend, and I would like to share with you his photographies of great examples of thrusts, duplexes and chevron folds in Devon (England) and Galicia (Spain).

http://myweb.facstaff.wwu.edu/talbot/cdgeol/Structure/Faults/Devon_Spain.html

(duplex with 8 horses, Widemouth Bay, Devon)

A duplex, as a reminder, is an array of thrust horses bounded by a floor thrust (i.e. sole thrust) at the base and by a roof thrust at the top (McClay, 1992).

You can also visit the homepage and enjoy the wonderful photographies, with very good examples from many places around the planet. Enjoy!

More about thrusts and duplex systems: McClay, KR, 1991, Glossary of thrust tectonics terms, in KR McClay, ed., Thrust tectonics: London, Chapman & Hall, p. 419–433

Prophet-predicted quake in Rome

I always say that  superstition is a tumour in our modern society. We are the best informed and educated generation ever, but we keep following irrational pulses.

Why I say that now? Because thousands of people are staying out of Rome for the next days over a rumour predicting the city devastation today, May 11 of 2011.

http://www.bbc.co.uk/news/world-europe-13354988

As the BBC story reads, these fears come after a rumour which states that seismologist Raffaele Bendandi, died in 1979, had predicted in his notes the destruction of Rome by an earthquake today. In reality, there is not any prediction about an earthquake in his notes. But, do we care? Have we lost our brains? Have we put them in stand-by?

Enter darkness, exit common sense.

Structural geology in Cabo Peñas (Asturias, Spain). Part I

(Click on the images for enlarging them)

I live and work in London, but I was born and raised in northern Spain, in Asturias. I studied Geology in the Universidad de Oviedo, in the foothills of the Cantabrian Mountains. Such a privileged geographical and geological location means a lot of fieldwork and great landscapes.

In short, the NW of the Iberian Peninsula is a remanent of the doubly vergent Hercynian Orogen (see figure attached), formed during the Devonian-Carboniferous time by the collision of Laurussia (or Euramerica) with Gondwana, forming Pangaea. The attached map shows the zonation of the Hercynian Massif in Iberia: the Centroiberian Zone (in green) is the crystalline core; the Ossa-Morena Zone and the Western Asturian - Leonese Zone are the metamorphic hinterland at both sides of the axis of the orogen; and the South Portuguese Zone and the Cantabrian Zone are the external areas of the foreland fold and thrust belts. The orogen strikes in NW-SE direction in the central area of Spain, and this evolves towards NE-SW direction in the North of Spain. This rotation occurs around the Asturian Arc (which is the eastern region of the Cantabrian Zone). Figure 2 shows cross section approximately WNW-ESE, cutting through the north coast of Spain, from Galicia to Asturias.

Cross section of the Hercynian Orogen in Northern Iberia

The Narcea Antiform separates in Asturias the Western Asturian - Leonese Zone (WALZ) and the Cantabrian Zone (CZ). The WALZ is characterised by a generalised regional metamorphism, increasing westwards, whilst the CZ it is not affected by metamorphism, being deformed by thrusts and folds.

The Cape Peñas is in the Cantabrian Zone, which is portraited in t headjacent diagram. It presents a Palaeozoic succession which is partially covered by the Mesozoic-Tertiary basin, including materials from the Permo-Triassic to Neogene.

So, enough of introduction!

In this article I want to show you some pictures we did in the Bay of Llumeres. Llumeres is in the eastern side of Cabo Peñas (the most prominent cape in Asturias), and it is part of the Cantabrian Zone of the Hercinian Massif in Spain. The following cross section (looking onshore from the sea, so WNW to the right, ESE to the left), shows the general structure of the place.

Basically, in Llumeres there are very good examples of polyphase deformation: a first phase forms the recumbent and overturend folds with east vergency, and also develops a weak slaty cleavage. The second phase of deformatin forms kink-bands and crenulation cleavage.

You can find more information in the following classic paper, written in the 70's by Julivert. It is in Spanish, but I strongly recommend you to take a look at, as the diagrams are beautiful and the photographies very clear (although in B&W). Note that my first two pictures are intentionally a copycat of the first two plates of the paper!

http://www.geol.uniovi.es/TDG/Volumen08/TG08-10.PDF

The first picture shows a beautiful overturned chevron antiform in Formigoso Shales Fm (Silurian). This fold is a first deformational phase structure. Some kink-bands (second phase) are visible. This fold is tagged as "A" in the schematic cross section presented above.


Second picture is a fantastic overturned chevron anticline. The anticline, formed during the first phase of deformation, shows very good examples of kink-bands developed during the second phase of deformation. Note also the M fold in the hinge of the structure, and the Z folds in the right flank.

The following two pictures portrait a fault-propagation fold, which, above the competent units where the cover of the camera lies, triggers the formation of a normal fault in order to accommodate the deformation:


Mineralization of pirite, afected by the second phase of deformation:


A synform, depicting the presence of quartzitic veins formed during the folding process. The synform also shows a hinge fault.

Syncline-anticline combination, with a fault cross-cutting the syncline:


And finally, a tight chevron fold, with M, and gentle S and Z parasitic folds:


Bibliography:
Manuel Julivert (1976). La estructura de la región del cabo Peñas Trabajos de Geología, 8, 203-309