Peridotite Nodule Bomb3D Model
This volcanic bomb contains a spectacularly fresh peridotite nodule about 12 cm across. More specifically, the nodule appears to be a spinel lherzolite dominated by olivine (olive green) along with smaller amounts of diopside (dark green), enstatite (pale greyish) and spinel (reddish brown).
The bomb itself is composed of basalt scoria as shown by the abundant vesicles present. However, the nodule has not crystallised from the basaltic lava that erupted, but rather is a xenolith that has been dragged up with the basalt from the solid mantle below. In essence, this would be what the upper mantle would look like if you could see it.
I am unsure of the exact location the sample was collected but it was recorded to be from the ‘Cambelltown Volcanics’ in Victoria - part of the Newer Volcanics. Its age would be about 10 ka.
CC Attribution-NonCommercialCreative Commons Attribution-NonCommercial
Comments