| | |
| | |
Stat |
Members: 3643 Articles: 2'487'895 Articles rated: 2609
28 March 2024 |
|
| | | |
|
Article overview
| |
|
Single-domain chemical, thermochemical and thermal remanences in a basaltic rock | Ulrike Draeger
; Michel Prévot
; Thierry Poidras
; Janna Riisager
; | Date: |
25 Oct 2005 | Affiliation: | Tectonophysique), Michel Prévot (Tectonophysique), Thierry Poidras (Tectonophysique), Janna Riisager (Tectonophysique | Abstract: | Tiny basaltic samples containing finely grained titanomagnetite with Curie temperature less than 100 C were heated in air in weak field (25 to 100microT) at temperatures between 400 and 560 C for times as long as 32 hours. Oxyexsolution of titanomagnetite resulted in the crystallization of interacting single domain particles with Curie point close to 540 C and the concomitant development of one of two types chemical remanence, depending upon thermal treatment: isothermal chemical remanence (CRM) or thermochemical remanence (TCRM), the latter acquired under the combined effects of chemical change and temperature decrease. CRM and TCRM acquired under various conditions were subjected to Thellier-type experiments. The CRM/TRM ratio is found to be less than one and increases rapidly with acquisition temperature (0.35 at 400 C, 0.65 at 450 C, and 0.90 at 500 C). Thus, very large underestimate of geomagnetic field paleostrength can occur when a natural CRM is not recognized as such and is believed to be a natural TRM. In an attempt to mimic deuteric oxyexsolution in cooling magma, TCRM was imparted from 560 to 400 C at a cooling rate of 0.1 C/mn. The TCRM/TRM is found to slightly exceed one (1.10), in agreement with the theoretically predicted effect of the difference in cooling rate. | Source: | arXiv, physics/0510231 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser claudebot
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |