| Abstrakt: |
Iran is a remarkable geoscientific laboratory where the full range of processes that form and modify the continental crust can be studied. Iran's crustal nucleus formed as a magmatic arc above an S-dipping subduction zone on the northern margin of Gondwana 600–500 Ma. This nucleus rifted and drifted north to be accreted to SW Eurasia ∼250 Ma. A new, N-dipping subduction zone formed ∼100 Ma along ∼3,000 km of the SW Eurasian margin, including Iran's southern flank; this is when most of Iran's many ophiolites formed. Iran evolved as an extensional continental arc in Paleogene time (66–23 Ma) and began colliding with Arabia ∼25 Ma. Today, Iran is an example of a convergent plate margin in the early stages of continent-continent collision, with a waning magmatic arc behind (north of) a large and growing accretionary prism, the Zagros Fold-and-Thrust Belt. Iran's crustal evolution resulted in both significant economic resources and earthquake hazards. Iran is a natural laboratory for studying how convergent plate margins form, evolve, and behave during the early stages of continental collision. Iran formed in the past 600 million years, originating on the northern flank of Gondwana, rifting away, and accreting to SW Eurasia. Iran is actively deforming as a result of collision with the Arabian plate, but earthquakes do not outline the position of the subducting slab. The Cenozoic evolution of Iran preserves the main elements of a convergent plate margin, including foredeep (trench), accretionary prism, and magmatic arc. [ABSTRACT FROM AUTHOR] |
