Paleomagnetism and magnetic fabric of Middle Jurassic dykes from Western Patagonia, Argentina

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

Jurassic volcanism in Patagonia is widespread. Although associated dyke swarms are conspicuous, they have been almost neglected in previous geologic studies of this region. Radiometric, paleomagnetic and magnetic anisotropy studies are reported from a Middle Jurassic basic to intermediate dyke swarm exposed in the Sierra de Mamil Choique (Western Patagonia) in an area of over 350 km2. Two whole-rock K/Ar determinations indicate that these dykes were intruded at around 170 Ma. An anisotropy of magnetic susceptibility (AMS) study on 15 dykes (74 block samples) shows that they carry different kinds of magnetic fabric (both normal and inverse), apparently governed by compositional differences. A paleomagnetic study of these samples suggests that Ti-poor titanomagnetite is the probable carrier of the characteristic remanence. Mean site characteristic directions pass a reversal test (grade C). A paleomagnetic pole, computed by averaging VGPs from each individual dyke, is situated at 70.2°S, 190.4°E (N=13, α95=9.7°), not substantially apart from other Middle Jurassic poles from South America. Further refinement of the Jurassic South American apparent polar wander path is needed to establish whether or not the Mamil Choique dykes were affected by a small tectonic rotation.

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

Paleomagnetism and magnetic fabric of Middle Jurassic dykes from Western Patagonia, Argentina 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 Paleomagnetism and magnetic fabric of Middle Jurassic dykes from Western Patagonia, Argentina, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Paleomagnetism and magnetic fabric of Middle Jurassic dykes from Western Patagonia, Argentina will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1247452

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