Palaeomagnetism of Permian red beds in the contact aureole of the Tertiary Adamello intrusion (northern Italy)

Details Palaeomagnetism of Permian red beds in the contact aureole of the Tertiary Adamello intrusion (northern Italy) Palaeomagnetism of Permian red beds in the contact aureole of the Tertiary Adamello intrusion (northern Italy)

Nov 1988

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1988pepi...52..365k&link_type=abstract

Physics of the Earth and Planetary Interiors, Volume 52, Issue 3-4, p. 365-375.

Physics

6

Scientific paper

Permian clastic red beds of the Verrucano Lombardo formation have been contact metamorphosed by Eocene-Oligocene calc-alkaline intrusions of the Adamello massif (Southern Alps). The magnetization of the unmetamorphosed or at most anchimetamorphosed sediments outside the contact zone is controlled by pigmentary and detrital haematite. The pigment haematite is converted to biotite in the contact zone, where magnetite and pyrrhotite are also generated in the zone of highest-grade metamorphism. The detrital haematite (martite and titanohaematite), however, survives even in close proximity to the intrusion, where temperatures around 600°C have been reached.
An apparent paradox is found: the structure of natural remanent magnetization (NRM) becomes less complex with increasing chemical changes owing to contact metamorphism. Except for viscous components, the NRM of the unmetamorphosed red beds consists of two magnetizations: an early acquired Permian component and a later overprint of Tertiary age. Owing to the natural chemical demagnetization, however, which removed the pigmentary haematite, a simple one-component NRM is often found in the metasediments of the contact zone. This magnetization is either of Permian origin, residing in the original detrital haematite, or of Tertiary age. The latter palaeomagnetic component is carried mainly by secondary haematite formed during contact metamorphism. The Permian magnetization has partly survived even in the highest metamorphic (andalusite) zone.

Affiliated with

Also associated with

No associations

Rating

Palaeomagnetism of Permian red beds in the contact aureole of the Tertiary Adamello intrusion (northern Italy) 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 Palaeomagnetism of Permian red beds in the contact aureole of the Tertiary Adamello intrusion (northern Italy), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Palaeomagnetism of Permian red beds in the contact aureole of the Tertiary Adamello intrusion (northern Italy) will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1827774