Ernst and Buchan developed a method for mapping remnants of these features that date to before the Mesozoic era by tracing their precursors to the convergence points of giant radiating dike swarms.
One of these geologic features contains a unique mineral whose closest relatives are picrite and komatiite and whose type locality is the Meimecha-Kotuj province. Ernst and Buchan developed a method for mapping remnants of these features that date to before the Mesozoic era by tracing their precursors to the convergence points of giant radiating dike swarms. These continental features have a concentration of incompatible elements that is intermediate between mid-ocean ridges and ocean island basalts. In the mantle plume hypothesis, these features are plume heads and hotspots are plume tails. The Chicxulub impact event caused accelerated outgassing from one of these features that may have contributed to the Cretaceous extinction. For 10 points, identify these "stairstep" landforms created by eruptions from volcanic  ssures, examples of which cover large areas of Siberia and the Deccan plateau.
One of these geologic features contains a unique mineral whose closest relatives are picrite and komatiite and whose type locality is the Meimecha-Kotuj province.
traps [or continental flood basalts; or CFBs; or large igneous provinces; or LIPs; or Siberian traps; or Deccan traps; prompt on basalts or lava  lows; do not accept "oceanic plateaus" or "mantle plumes"]