Geology MCQ Practice Q.1 The density contrast across which one of the following transitions in the Earth is maximum? (A) Upper crust - lower crust (B) Upper mantle - lower mantle (C) Lower mantle - outer core (D) Outer core - inner core Q.2 Which one of the following is NOT an ultramafic rock? (A) Wehrlite (B) Olivine websterite (C) Harzburgite (D) Anorthosite Q...