Obduction 222
Troduce various combinations of obduction, subduction and collision with different P-T-t signatures. Rapid reversal of plate kinematics favor the largest, Oman-type obductions but other geodynamic circumstances in In particular, Alpine and Himalayan obductions were broadly coeval with collision (respectively during Late Cretaceous and Eocene times) and involved rather old and deformed oceanic lithosphere. Other Tethyan obductions followed still different scenarios. It is, first and foremost, a puzzle-solving game, though a rich story is told through both the puzzles and the environment Obduction Walkthrough Guide (Paperback).
#Obduction 222 series
Continental collision did not occur in Oman, while it affected the coeval Taurus obduction after a 40 Ma span of time. Obduction is a first-person adventure game developed and published by Cyan, Inc., the creators of the Myst series of video games. The Late Cretaceous Oman obduction affected an area of very recent continental crustal thinning and oceanic accretion (spreading changed to convergence within 5 Ma). Such metamorphism is like that developed within collisional settings (Western Alps) and different from the subduction type (East-Pacific belts). The P-T evolution began with a stage of relatively high thermal gradient typified by counter-clockwise paths in the upper nappes of the prism. The inner parts of the prism were affected by HP-LT recrystallization up to the eclogite facies in the deepest slices. During the second, subaerial stage, a thick tectonic prism composed of continental cover and basement rocks formed under the thrust slab. At the end of this submarine stage, the oceanic slab moved onto the continental margin while bulldozing volcanic and sedimentary formations into a nappe complex. Such phenomenon might have occurred at a recently active mid-ocean ridge. By contrast, we argue that the magmatism must be ascribed to the fusion of an hydrated, thin mantle wedge at shallow depth during the lithospheric duplication,with partial anatexis in the HT-LP metamorphic sole at the base of the ophiolite.
The first stage was accompanied in the upper plate by a differentiated magmatism that has previously been ascribed to subduction. This lithosphere shortening is a process distinct from subduction and collision. It involved two main stages of thrusting of oceanic lithosphere: i) onto the adjacent oceanic crust and lower continental margin, without emergence ii) onto the upper continental margin, with emergence of the ophiolite. The Oman obduction can be considered as the type-obduction.