A paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: implications for CRM related to hydrothermal alteration

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

7

Scientific paper

Paleomagnetic and rock magnetic data combined with stable isotope data from the middle Tertiary pluton along the Rio Hondo in northern New Mexico suggest that its magnetic remanence has both thermal (TRM) and high-temperature chemical (CRM) components. Oxygen isotope temperatures indicate that magnetite associated with the more rapidly cooled higher levels of the pluton, and with mafic inclusions and cogenetic rhyolitic dikes sampled at lower levels of exposure, ceased subsolidus recrystallization and isotopic exchange above its Curie temperature (580°C) in the presence of a magmatic fluid. Continued cooling imparted a TRM to these portions of the pluton. The more slowly cooled granodiorite at lower levels has quartz-magnetite isotopic temperatures that are below the Curie temperature of magnetite implying that its magnetization is high-temperature CRM. Sub-Curie isotopic temperatures for other granitic plutons in the western U.S.A. suggest that CRM may be commonly derived from subsolidus interactions between magnetite and magmatic fluids in plutonic rocks. A meteoric-hydrothermal system generated by the cooling Rio Hondo pluton, and not by younger adjacent intrusions, resulted in limited alteration along zones of high permeability near the southern margin of the Rio Hondo pluton, and in more prevasive alteration of the pluton to the north. The meteoric-hydrothermal alteration occurred at relatively high temperatures (> 350°C) and, with the exception of local chloritization, caused little visible alteration of the rocks. The isotopic ratios indicate that little of the magnetite could have grown from or exchanged with a meteoric-hydrothermal fluid.

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

A paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: implications for CRM related to hydrothermal alteration 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 A paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: implications for CRM related to hydrothermal alteration, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A paleomagnetic and stable isotope study of the pluton at Rio Hondo near Questa, New Mexico: implications for CRM related to hydrothermal alteration will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1831933

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