Mexico 2014

 

 

In the november 2014, I conducted fieldwork along the Pacific coast of Mexico in the Guerrero terrane within the context of the PhD project of my student Lydian Boschman. We were joined by collaborator and friend Roberto Molina-Garza from the Univeridad Nacional Autonoma de Mexico (UNAM) at Queretaro. The purpose of Lydians project is to try to develop plate kinematic reconstructions of now-subducted ocean floor of the Panthalassa ocean, using offscraped relics and marginal arcs and basins. During this trip, we tried to find subduction melanges reported in the literature (not successful) and to take paleomagnetic samples from the Guerrero intra-oceanic terrane that formed outboard the Mexican continental margin during the Cretaceous (very successful). Below you find a photo impression of the trip.

 

 

 

 

 

 

 

Lydian Boschman, PhD student at Utrecht University

 

 

 

 

 

 

 

 

 

 

 

 

Roberto Molina Garza, Professor of paleomagnetism and tectonics, UNAM, Querataro, Mexico

 

 

 

 

 

 

 

 

 

 

 

...and me

 

 

 

 

 

 

 

 

 

Lydian, during the loading of the UNAM truck prior to departure

 

 

 

 

 

 

 

 

 

 

 

Our host institution!

 

 

 

 

 

 

 

 

 

 

 

 

We tried to find radiolarian cherts accreted from subducted Pacific crust. Instead we found clastic sediments overprinted by contact aureoles around intrusions, here with large andalusite crystals. Not very useful for our purposes

 

 

 

 

 

 

 

 

Next try...nope, metamorphic blocks, presumed to be blueschists, but I could find the glaucophane. Not what we're after, in any case.

 

 

 

 

 

 

 

 

But a nice scenery nevertheless

 

 

 

 

 

 

 

 

 

 

 

Lydian, documenting

 

 

 

 

 

 

 

 

 

 

 

 

...and getting stared at :)

 

 

 

 

 

 

 

 

 

next target then: redbeds within the Guerrero arc sequence, to determine the paleolatitude of this arc. Roberto takes a swing to see if these redbeds are any good.

 

 

 

 

 

 

They were! Lydian, drilling them to Swiss cheese

 

 

 

 

 

 

 

 

 

Roberto and I, documenting the section and collecting samples

 

 

 

 

 

 

 

 

Lydian, carrying water to a drill site

 

 

 

 

 

 

 

 

 

Drilling...

 

 

 

 

 

 

 

 

 

 

 

...drilling some more

 

 

 

 

 

 

 

 

 

 

 

...in impossible positions

 

 

 

 

 

 

 

 

 

 

 

 

 

...very concentrated

 

 

 

 

 

 

 

 

 

 

 

...and measuring sample orientations

 

 

 

 

 

 

 

 

 

and plunge measurements

 

 

 

 

 

 

 

 

 

 

 

Added benefit of fieldwork in Mexico: the landscape is spectacular!

 

 

 

 

 

 

 

 

 

 

Beach at sunset

 

 

 

 

 

 

 

 

 

You drive around and suddenly you pass a smoking volcano...Colima in this case

 

 

 

 

 

 

 

 

 

Same volcano, Colima is the one on the left.

 

 

 

 

 

 

 

 

Another day at the office...if there's no road, you take a river :)

 

 

 

 

 

 

 

 

 

Morning fog

 

 

 

 

 

 

 

 

 

...Fog over the Lago de Cuitzeo

 

 

 

 

 

 

 

 

 

Idyllic ponds in the jungle

 

 

 

 

 

 

 

 

 

Yuca plans overgrowing outcrop

 

 

 

 

 

 

 

 

 

 

Sugar cane fields on fire, harvest time

 

 

 

 

 

 

 

 

 

Amazing valleys

 

 

 

 

 

 

 

 

 

me, taking pictures of a butterfly

 

 

 

 

 

 

 

 

 

This one :)

 

 

 

 

 

 

 

 

 

almost transparrent dragonfly

 

 

 

 

 

 

 

 

 

 

 

Cool spiders!

 

 

 

 

 

 

 

 

 

 

 

Some more

 

 

 

 

 

 

 

 

 

This one doesn't look very pleasant

 

 

 

 

 

 

 

 

 

Orchids!

 

 

 

 

 

 

 

 

 

In other words, more than enough to come back to! Can't wait!