Transport and eruption of mantle xenoliths creates a lagging problem

Mantle-derived xenoliths entrained by low-viscosity magmas indicate transport through significant thicknesses of orogenic and cratonic mantle lithosphere. Xenolith size and density cause continuous settling during transport, creating a lag time between magma reaching the surface and xenolith arrival. This lag time depends on xenolith properties, sampling depth, and magma ascent velocity. The paper uses settling calculations to show how eruption durations and volumes impact xenolith distribution, abundance, and properties. Lag times explain heterogeneous xenolith distributions, potential biased mantle sampling, and constrain minimum eruption volumes for transporting deep-sourced xenoliths, such as those in diamondiferous kimberlites.

James K. Russell, Thomas J. Jones