To increase the amount of virtual memory go to Control Panel > System > Advanced > Performance > Settings > Advanced > Virtual Memory Change > Custom Size > adjust as needed. 2 times your physical RAM is a good minimum and 3 times your physical memory in MB is good for your maximum.
Mafic lavas are lavas rich in iron and magnesium, while being low in silica. Basalt is the solidified version of mafic lava. Mafic lavas are the most common lava type on earth. Mafic lavas are also the hottest lavas and normally erupt at over 900 degrees Celsius - that's 1,650 degrees Fahrenheit!
Over 700 different types of igneous rocks have been discovered to date. These vary in terms of appearance, grain size and amount of time that it takes for the lava to cool. A common igneous rock rule is that if lava cools at a faster rate, the rock formed will have finer grains and have a glassy appearance; if rock cools at a slower rate, the grains will be larger and more coarse.