Page 27 - Curriculum Visions Dynamic Book. To close the book, close the tab.

Lava
 Lava—As this fast flowing river of runny lava quickly changes course, it engulfs nearby forests that have grown on old lava flows. This is Hawaii.
it can have a broken surface, in which case it is called aa lava. There are also some special,
and very interesting, forms of lava. If lava cools very quickly, it forms a black volcanic glass with no crystals or air bubbles in it. It
is called obsidian. The surface of sticky lava is often puffed up by gases expanding in the molten lava. When it cools, it produces a very lightweight material called pumice.
Here are two examples of places with different types of lava: Hawaii is the largest of the Hawaiian chain of volcanic islands in the Pacific Ocean. The magma that rises to the surface there produces runny, basalt lava. The runniness of the lava
can be seen in several ways.
First, the lava spurts up above the vent as a lava fountain. Then
it runs in rivers down the sides
of the volcanoes for many tens
of kilometers. (See also: Shield volcano.)
Mount Pinatubo, in the Philippines, is a major volcano
in eastern Asia. The magma from Mount Pinatubo is sticky, and most of it is ejected as tiny fragments
of lava that cool to produce ash. The lava that flows from the vent toward the end of the eruption rarely travels far.
(For other types of lava see: Ash; Bomb; Lava flow; Lava lake; Lava tube; Pele’s hair; Pele’s tears; Pillow lava; Rhyolite; Spatter.)
 Lava—The Hawaiian Islands’ lava flows boil the water as they ooze into the sea. The solidifying lava adds new land.
27