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!
The main composition types are mafic, which are lavas rich in iron and magnesium, while being low in silica; intermediate, which are lavas with medium amounts of iron, magnesium, and silica; and felsic, which are lavas that have the highest silica and lowest magnesium concentration.