Xenolith evidence for lithospheric melting above anomalously hot mantle under the northern Canadian Cordillera

Article Abstract:

The harzburgite xenoliths of seven mantle xenolith suites in the northern Canadian Cordillera formed by partial melting of the lower lithosphere in response to the rise of fluids and heat from anomalously hot asthenospheric mantle below. This was gleaned from a study of both major and trace element data from the seven suites. Findings show that there are two types of xenolith suites in the area, namely, unimodal suites comprised mainly of fertile lherzolite xenoliths and bimodal suites with both fertile lherzolites and refractory harzburgites.

Canada, Xenoliths

---

Crustal contamination in early Basin-and-Range hawaiites of the Los Encinos Volcanic Field, central Mexico

Article Abstract:

A study of the mineral content in the Los Encinos Volcanic Field hawaiites in central Mexico reveals the existence of large quantities of megacrysts and xenocrysts and minimal amounts of rare granulite xenoliths in these hawaiites, which undergo elemental impacts of crustal contamination. However, unlike in other volcanic locations, lower crustal contamination in these hawaiites does not lead to barium accumulation, suggesting the possible extraction of elements such as thorium and uranium toward the volcanic surface by ascending magmas.

Mexico, Observations, Volcanological research

---

The relationship between the hawaiites and basalts of the Itcha Volcanic Complex, central British Columbia

Article Abstract:

Fractional crystallization from parental magmas is responsible for formation of the hawaiites and the Fe-rich alkali olivine basalt (AOB) lavas of the Itcha Volcanic Complex, central British Columbia. The process involves high-pressure fractionation of a clinopyroxene-dominated wehrlite assemblage. The presence of high Sr/Zr ratios in these rock types shows this. The Sr/Zr ratios are low in Fe-poor AOB lavas, evolving from AOB parental magmas at comparatively low pressures.

Analysis, Basalt, British Columbia, Igneous rocks, Formations (Geology), Geological formations

Similar abstracts:

• Abstracts: Neodymium isotopic evidence for the tectonic assembly of late Archean crust in the Slave Province, northwest Canada
• Abstracts: Evidence for a reduced, Fe-depleted martian mantle source region of shergottites. A revised and internally consistent thermodynamic model for the interpolation and extrapolation of liquid-solid equilibria in magmatic systems at elevated temperatures and pressures
• Abstracts: Phanerozoic biodiversity mass extinctions. Evolution of the North American Cordillera. Madagascar: heads it's a continent, tails it's an island
• Abstracts: An experimental study of the Fe-Mn exchange between garnet and ilmenite. Experimental tests of garnet peridotite oxygen barometry
• Abstracts: Parental expenditure and offspring sex ratios in the dioecious plant Silene alba. Population structure influences sex ratio evolution in a gynodioecious plant

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.