|
ИСТИНА |
Войти в систему Регистрация |
ФНКЦ РР |
||
Determination of the Formation Field of Artificial CRM and pTRM by the Thellier Method at Different Oxidation Stages of Natural Titanomagnetiteстатья Исследовательская статья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 7 июля 2020 г.
- Авторы: Maksimochkin V.I., Grachev R.A., Tselebrovskiy A.N.
- Журнал: Izvestiya. Physics of the Solid Earth
- Том: 56
- Номер: 3
- Год издания: 2020
- Издательство: Pleiades Publishing, Inc.
- Местоположение издательства: New York, USA
- Первая страница: 413
- Последняя страница: 424
- DOI: 10.1134/S1069351320030040
- Аннотация: Artificial chemical remanent magnetization (CRM) created on a basalt rock from the Red Sea riftzone, originally containing titanomagnetite (TM) with a Curie temperature of 203–208°С, is studied at various oxidation stages. CRM was formed by annealing the samples at temperature T = 355°C during 4.5–350h in the magnetic field with induction of 100 μT. The thermomagnetic analysis has shown that with the increase of the annealing time, a single-phase oxidation process takes place, the degree of the oxidation increases and reaches its maximum after annealing during 110 hours. It is established that the subsequent heating of the samples to 600°C in argon leads to the homogenization of the single-phase-oxidized titanomaghemite. When the annealing time increases to 350 h, oxi-exsolution of titanomaghemite begins. CRM as well as the sum of CRM and partial thermoremanent magnetization (pTRM) have been investigated by the Thellier–Coe procedure.The magnetic field Bcalc calculated in the temperature interval 355–475°C from chemical magnetizationformed at the annealing times of 4.5, 16.5, and 40.5 h (CRM4.5, CRM16.5 and CRM40.5) proved to beunderestimated by 55, 48–52, and 16–34%, respectively. The difference between the calculated and true field decreases with the growth in the degree of single-phase oxidation. The Bcalc values calculated in the temperature interval 475–580°С from CRM40.5 and CRM110 corresponding to the high degree of single-phase oxidation turned out to be underestimated by 69–72 and 62–63%. The last result is caused by the mineral transformations of titanomaghemite at heatings in the Thellier–Coe experiments. During paleointensity determination, it is proposed to control mineral transformations not only using the check-point procedure but also based on the difference in the removal of remanent magnetization in the Thellier experiments and by thermal demagnetization.
- Добавил в систему: Максимочкин Валерий Иванович