1. 30 years of P-T-t paths: What we’ve learned about orogenesis
Frank S. Spear
Rensselaer Polytechnic Institute

2. (1977)

3. P-T paths from zoned garnet
Tauern Window, Austria
(Selverstone et al, 1984)

4. Tauern Window,
Austria
(Selverstone et al, 1984)

6. P-T paths and nappe tectonics - New Hampshire
Spear et al. (2007)
Ernst, 1976

8. Trace element thermobarometry
Ti-in-quartz (Titaniq)
Y in garnet

9. Y zoning in garnet BF-17A - Western New Hampshire
TM Strafford Dome, Central Vermont
4341 ppm - inner core
5346 ppm - outer core
29 ppm - rim

10. garnet + xenotime assemblages
Y concentration in
garnet + xenotime assemblages
Tectonic loading at rates in excess of
8 cm/year

11. Rates of tectonic processes
Diffusion studies:
Rates of tectonic processes
Ti-in-quartz (Titaniq)
Mn in garnet

12. 79-149d (New Hampshire: kyanite zone)
Grt St Ky
Grt

13. 79-149d (New Hampshire: kyanite zone)
CL image
Grt

14. 79-149d (New Hampshire: kyanite zone)
CL image
Grt

15. 79-149D Orfordville, NH: kyanite zone
CL image
Qtz
Grt

16. Peak T/Duration
550C/1.2 m.y.
575C/0.6 m.y.
600C/0.3 m.y.

17. TM-730 - Central VT. Staurolite-Kyanite zone

18. TM-730
Mn zoning

19. TM-730 - Mn diffusion modeling
2.5 m.y.
0.25 m.y.

23. 10 cm/year

24. 10 cm/year