NOTE THAT THE PRE- AND POST CONFERENCE FIELD-TRIPS ARE ALREADY FULLY BOOKED. SINCE JUNE 6 REGISTRATIONS FOR FIELD TRIPS ARE CLOSED.
FROM PASSIVE MARGINS TO OROGENS:
THE LINK BETWEEN OCT ZONES & (U)HP METAMORPHISM
September 2-3, 2013
Minimum participants: 25
Maximum participants: 50
This excursion is aimed at illustrating the evolution of ophiolite-bearing lithosphere from Jurassic rifting to Eocene-Oligocene high-pressure metamorphism.
Mountain boots, sun glasses, and sun-tan lotion are strongly recommended, as well as warm, water- and windproof clothes, since weather can change rapidly in Alpine settings.
September 2, 2013
From OCT’s to diamonds: the Lago di Cignana Unit
Altitude: ca 2000 m a.s.l.
Elevation gain (on foot): a few tens of m
Field leaders: Roberto Compagnoni, Maria Luce Frezzotti, Gordon Lister, Daniele Regis
On the second day we will visit the UHP Lago di Cignana Unit, hosting exceptionally well preserved UHP assemblages in both eclogites and early-post rift quartzitic metasediments, formed during Eocene subduction of the Jurassic oceanic crust. We will observe eclogites with lawsonite pseudomophs, phengite and glaucophane, and Mn-rich quartzitic metasediments with garnet-, omphacite-, and zoisite-bearing layers. The recent discovery of micro-diamonds in garnets from the Mn-rich quartzites attests to the great depth reached by the Lago di Cignana Unit during subduction.
The Lago di Cignana (Cignana Lake) is located in a beautiful high mountain landscape not far from the Matterhorn visible during the uphill driving.
September 3, 2013
Walking on a hyper-extended margin: the Versoyen Unit
Altitude: 2200-2600 m a.s.l.
Elevation gain (on foot): ca. 400 m
Field leaders: Jaime Barnes, Marco Beltrando, Gianluca Frasca
During the first day, in the Valaisan domain, cropping out at the Petit St. Bernard pass, we will show that continental basement, serpentinized sub-continental mantle and meta-sediments preserve relationships typical of the Zones of Exhumed Subcontinental Mantle observed along present-day magma-poor rifted margins. This excursion aims at illustrating that this complex llithological association, which is common to several Alpine metamorphic terranes, is not necessarily/exclusively related to complex subduction dynamics. Primary relationships between the different rock types can still be inferred, despite multi-stage Alpine deformation and metamorphism at P≥1.5 GPa. Multi-stage interaction between ultramafics and the surrounding rock types will also be discussed, based on stable isotope data.
This field trip will involve hiking on moderately steep paths, providing access to breathtaking views of the highest peaks in the area (Mont Blanc, Matterhorn, Ruitor).
The Geological Fieldtrip GUIDE of the pre-Conference excursion can be downloaded (“Scarica la pubblicazione”) at: