About

I am a geoscientist crazy about knowing more and more about plate tectonics in general, geology of supercontinents, supercontinent cycle, Wilson cycles, lithospheric dynamics and the origin of curved orogenic belts and oroclines.

At present I work at Tohoku University (Japan) as a JSPS fellow and I try to uncover how the Panthalassa and Rheic/Paleotethys interacted during the Late Paleozoic.

 

Supercontinents
Earth’s landmasses tend to amalgamate altogether into supercontinents following a quasi-periodic cycle since the origin of plate tectonics. A supercontinent is, ideally, the assembly of all of the continental plates into a single large one. However, The definition is somewhat be ambiguous and in general the term “supercontinent” is used as a clustering of the majority of continents. In such way there is some room for interpretation, for instance Gondwana is classify as a supercontinent by some authors whereas others state it was not. Amalgamation and dispersal of supercontinents have had a profound effect on the evolution of the Earth’s crust, atmosphere, climate, and life involving a countless number of processes such as subduction dynamics, plate and micro-plate transfer (rifting, drifting, accretion), orogenesis, orocline buckling, changes in mantle dynamics, activity of large igneous provinces and deep mantle plumes, etc. However, the number of unsolved questions is large, How and why they form? Is the quasi-cyclicity related with deep levels or the Earth or is just a coincidence into the plate circuits? Which are the similarities and differences between the different supercontinents?

I have those questions in mind and I try to join pieces together to solve them. Most of my research is tightly related with the latest Supercontinent, Pangea. Rocks realated with this supercontinent are better exposed and therefore is our best template by which the origin of the older supercontinents can be evaluated.

Orogenic curvature
Orogens extend hundreds to thousands of kilometers across Earth’s surface, and while they are roughly linear in plan, all are to some degree curved or bent when observed in map view. Some of this bends are striking, for example, the western end of the Paleozoic Variscan Orogen of Europe is characterized by a 180° hairpin bend that affects a 500 km wide mountain system. My PhD thesis dealt with the formation of that curvature from a multidisciplinary point of view. The orocline (as this bends are named) is recognized by geometrical changes in the structural trend of thrust-related folds that formed during the Carboniferous Variscan orogeny. The orocline has a convex-to-the-west shape, an E-W axial trace, and an isoclinal geometry in plan view. Both the northern and southern limbs of the orocline strike E-W, thus defining an arc with 180° of curvature. The Cantabrian Orocline is characterized as a foreland fold-thrust belt with thrust vergence toward the oroclinal core. Thrusts imbricate a Carboniferous foreland basin sequence, an underlying Lower Paleozoic passive margin sequence, and a basal Ediacaran slate belt. The distribution of sedimentary facies and paleocurrent data show that the Lower Paleozoic passive margin faced outward, away from the core of the orocline. The Variscan metamorphic hinterland surrounds the core of the orocline to the west and south, and is overthrust in the west by ophiolitic assemblages along foreland-verging thrusts.

Modern bends are equally impressive and of equivalent geological significance. Some of the greatest topographic relief on Earth is to be found associated with the still evolving tight bends that adorn the eastern and western ends of the Himalayas. Likewise, Earth’s second largest and highest plateau, the Altiplano of South America, sits astride, and reached its present elevation during formation of, the great Bolivian bend of the Andes. Other modern bends are the oroclines in the Lesser Caucasus and Talysh-Alborz ranges, where I have been working during my postdoc in Utrecht.

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