Torino scale the validity and societal impact of SETI data. The Torino Scale also uses a color code scale: white, green, yellow, orange, red. Each color code has an overall meaning: No object has ever been rated above level 4. The Chicxulub impact, believed by most scientists to be a significant factor in the extinction of the dinosaurs, has been estimated at 100 million (10) megatons, or Torino Scale 10. The impacts which created the Barringer Crater and the Tunguska event in 1908 are both estimated to be in the 3–10 megaton range, corresponding to Torino Scale 8. The 2013 Chelyabinsk meteor
Paired metamorphic belts barometric conditions within these 2 regions are recorded and preserved through distinct types of metamorphism and mineral assemblages. Detailed research on constraints of metamorphic mineral stability fields allows accurate inference of previous regional thermal and barometric conditions. Metamorphic belts are a consequence of thermal perturbations, due to low temperature with respect to pressure ratios (dT/dP) in oceanic trenches and high temperature with respect to pressure ratios (dT/dP) in arcs. Paired metamorphic belts are the product of subducted colder crustal rocks, which are taken to depth, metamorphosed and then exhumed. However, if the rock unit is not exhumed relatively quickly after