Honduras 2009

Chortis block

As part of my research project to make mantle-reference framed plate reconstructions of the (circum-) Caribbean region, I undertook a fieldtrip to Honduras in central America, which exhibits the so-called Chortis block. The Chortis block is a large (1000x1000 km) continental block that was likely derived from the west-ward moving North American plate (Mexico), but which became caught up in the relatively stationary Caribbean plate sometime after the Cretaceous. At present it is separated from the North-American plate by the Motagua-Cayman-Oriente transform fault system, which forms the plate boundary with the Caribbean plate. Only days before we went into the field, an M=7.3 earthquake hit Honduras, epicentered at the Swan Island fault, part of the Motagua-Cayman system. This fieldwork was carried out together with Rob Rogers, from the California State University at Stanislaus, the world’s leading specialist on Honduran Geology and Roberto Molina-Garza, a paleomagnetist from the Universidad Nacional Autónoma de México. Below the usual photo report of my fieldtrips, enjoy! Ow, and because Bart has been complaining about the small size of the pictures on my size for about 9 years now, I made them slightly larger. If your browser is slow because of this, blame Bart J

The crew

Rob ‘Ginger’ Rogers

Roberto Molina-Garza

Me…

And our invaluable field pick-up J

The action

Rob, scouting for drillable rock

Found some…see next picture to read the sign on top of the outcrop…

Rocks for sale J

Ain’t I good ...

Roberto, drilling the upper Atima formation of Cretaceous limestones

Drilling the flanks of a fold for a paleomagnetic fold test (i.e. if we correct for bedding tilt, we should find the same paleomagnetic direction in both fold limbs)

Measuring…

Getting the core out

Big fun, drilling red beds in the rainy season…

Roberto measuring my cores in a river bed…Rob studying a rock full of Cretaceous Rudist fossils (big bivalves, the light brown spots on the rock are all fossils)...