Which of the following minerals melts the easiest? olivine amphibole quartz K-Feldspar. Question 10 Fragmented material that sprayed out of a volcano and landed on the ground or sea floor in solid form is called lava. True False The resistance of material to flow is the rock's geotherm. True False Question 12 The process by which a magma becomes progressively more silicic as it cools, because early-formed crystals settle out is fractional crystallization. True False A fast-moving avalanche that occurs when hot volcanic ash and debris mix with air and flow down the side of a volcano is called a fissure eruption. True False Question 14 2 pts The sequence in which different silicate minerals crystallize during the progressive cooling of a melt is Peter's reaction series. True False.