 This suggests the record of the metamorphism 2.65 billion years ago was removed and overprinted by later metamorphic events.On top of that, the formation of greenstone and gneiss in Luxi and Qixia are considered to be linked to a wider geological event, the Large Igneous Province event 2.7 billion years ago.Magma was extracted and led to the formation of a mafic crust.