|
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ЦЭМИ РАН |
||
Density, temperature, and composition of the North American lithosphere-New insights from a joint analysis of seismic, gravity, and mineral physics data: 1. Density structure of the crust and upper mantleстатья
Статья опубликована в высокорейтинговом журнале
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: 10 августа 2018 г.
- Авторы: Kaban Mikhail K., Tesauro Magdala, Mooney Walter D., Cloetingh Sierd A.P.L
- Журнал: Geochemistry, Geophysics, Geosystems
- Том: 15
- Номер: 12
- Год издания: 2014
- Издательство: Geochemical Society
- Местоположение издательства: United States
- Первая страница: 4781
- Последняя страница: 4807
- DOI: 10.1002/2014GC005483
- Аннотация: We introduce a new method to construct integrated 3-D models of density, temperature, and compositional variations of the crust and upper mantle based on a combined analysis of gravity, seismic, and tomography data with mineral physics constraints. The new technique is applied to North America. In the first stage, we remove the effect of the crust from the observed gravity field and topography, using a new crustal model (NACr2014). In the second step, the residual mantle gravity field and residual topography are inverted to obtain a 3-D density model of the upper mantle. The inversion technique accounts for the notion that these fields are controlled by the same factors but in a different way, e.g., depending on depth and horizontal dimension. This enables us to locate the position of principal density anomalies in the upper mantle. Afterward, we estimate the thermal contribution to the density structure by inverting two tomography models for temperature (NA07 and SL2013sv), assuming a laterally and vertically uniform fertile mantle composition. Both models show the cold internal part and the hot western margin of the continent, while in some Proterozoic regions (e.g., Grenville province) NA07 at a depth of 100 km is >200 degrees C colder than SL2013sv. After removing this effect from the total mantle anomalies, the residual compositional fields are obtained. Some features of the composition density distribution, which are invisible in the seismic tomography data, are detected for the first time in the upper mantle. These results serve as a basis for the second part of the study, in which we improve the thermal and compositional models by applying an iterative approach to account for the effect of composition on the thermal model.
- Добавил в систему: Кабан Михаил Константинович