Eclogitization of lower crustal granulites by fluid migration through shear zones

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

83

Scientific paper

The granulite facies assemblages of the anorthositic rocks of the Bergen Arcs (stable at 800-900°C and 10 kbar) have been transformed to eclogite facies assemblages (stable at 700-750°C and 16-19 kbar) in the vicinity of Caledonian shear zones. This section of the root zone of the Caledonian mountain chain reveals a deep polymetamorphic crust where Precambrian granulites (mean density 3.02 g/cm3) and Caledonian eclogites (mean density 3.19 g/cm3) alternate on a scale of meters over a minimum area of 3 × 12 km. Detailed mapping of three localities shows that eclogites account for up to 30-45% of the rock volume. The stabilitization of the eclogite mineralogy is controlled by fluids penetrating these deep crustal shear zones. The eclogitization is independent of preexisting compositional variation in this anorthosite-norite complex. The Bergen Arcs example suggests that the amount of eclogite versus granulites in the lowermost crust is a function of deformation and fluid access, rather than being controlled by T, P and rock composition alone. These relationships may explain the gradual increase in seismic velocity observed in some deep crustal sections and also the complex reflection pattern obtained from the lowermost crust in many areas.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Eclogitization of lower crustal granulites by fluid migration through shear zones does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Eclogitization of lower crustal granulites by fluid migration through shear zones, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Eclogitization of lower crustal granulites by fluid migration through shear zones will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1623499

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.