This lends support to a controlling influence for lithospheric rifting zones on continental flood basalt generation and emplacement.
We have undertaken three independent field tests to determine whether the magnetization of the andesite and basalt sheets is primary.
These conglomerates are composed of clasts of basalt, volcaniclastic sandstone, alkaline lava and sub-rounded chert.
From about 128 km away, they hauled huge basalt boulders, from which to carve colossal heads, and nearly 100 other sculptures.
This is corroborated by the rather similar isotopic compositions of the alkali basalts and trachytes.
The combined effects of less erosion-resistant marly limestone and the columnar jointing of basalts caused the rapid migration of the knickpoint toward the upstream reach.
Soils are coarse inceptisols originating from 2-3 m of volcanic ash over basalt bedrock.
Mineral beads were added in order to reveal a possible influence of basalt and limonite on the molecular stability and formation of the derivatives.