An international field forum in Fiordland, New Zealand (April 26 to May 6, 2003) is providing members of the Solid Earth Science community with an opportunity to examine the mechanisms by which magma is generated, segregated and transported through continental crust and how these processes affect the mechanical evolution of the lithosphere. The Fiordland location is significant because few field sites allow geoscientists to examine directly structural and magmatic features that evolved simultaneously within large sections of the lower crust. Fiordland contains rare exposures of high-pressure migmatite and lower crustal structural features that formed at unusually deep levels of a Cretaceous mountain system (25-50 km paleodepths). The spectacular preservation of features at this site are stimulating new ideas and are providing a basis for evaluating the processes of melt generation and escape from the lower crust and how migrating magma interacts with deformation at the lithospheric scale. Specific issues addressed include: 1) evidence of rapidly evolving thermal and structural regimes in the lower crust and effects on lithosphere evolution; 2) evidence of fluid and melt sources and changing mechanisms of magma segregation and transport through the lower crust; 3) feedback mechanisms among crustal melting, granulite facies metamorphism and deformation; 4) effects of crustal melting and magmatism on vertical coupling/decoupling processes within the lithosphere; 5) flow patterns in natural lower crustal shear zones and their relationship to deformation and magma transport processes; 6) space-time controls on deformation partitioning and strain localization processes in the lower crust.
The unique geologic setting of Fiordland allows 30 geoscientists to exchange current knowledge and new ideas that are well expressed by the geology of specific field sites. This project also partially supports 5-8 students and a post-doctoral associate to attend the meeting. The participation of young scientists provides opportunities for students to meet other geoscientists conducting research in the same or similar fields of interest, but with different expertise. It also allows them to interact with mature scientists and an opportunity to study some spectacularly exposed deep crustal processes.
