The Saih Hatat window in Oman: An exceptionally well-exposed high-pressure metamorphic nappe complex that allows to study the return of deeply buried rocks back to the surface in unparalleled detail

The return (exhumation) of rocks from great depths (high-pressure (P) rocks) exceeding the thickness of the Earth’s crust remains a challenging problem.

Exhumed high-P complexes are commonly either not well exposed due to intense vegetation cover and weathering, have been highly extended and largely submerged, or occur in partly inaccessible high-relief terrain where exhumation structures have been strongly overprinted by collision tectonics. Therefore, the geometry of high-P complexes and critical tectonic contacts are still poorly understood.

Another common problem is that the timing of high-P metamorphism and its relationship to movement on tectonic contacts responsible for burying and exhuming them remains problematic.

Fundamental for making progress is to (1) structurally characterize tectonic contacts, (2) elucidate the transition of the high-P rocks with non-high-P rocks, (3) constrain the age of the high-P rocks and the timing of their exhumation and associated tectonic contacts, and, most importantly, (4) better understand the 3D geometry of high-P complexes.

An outstanding example are the high-P rocks exposed in the Saih Hatat window in Oman.

As there is almost 100% exposure, they represent an extraordinary opportunity to work out the complete, present-day tectonic geometry and the contacts of the complex.

This, combined with Rb-Sr multi-mineral, U-Pb posphate and calcite, and fault-gouge dating will allow to address the exhumation history in unparalleled detail.