then compacted (pressed together) over thousands of years usually in places where oceans or bodies of water did or still exist soft, layered, may contain fossils igneous quartz, pumice, granite, basalt, obsidian created when molten rock (lava) inside the earth pushes through the crust.
(obsidian; created; T:when molten rock (lava) inside the earth pushes through the crust) (molten rock (lava) inside the earth; pushes; through the crust) (oceans or bodies of water; did; )
obsidian molten rock (lava) inside the earth oceans or bodies of water
created pushes did
T:when molten rock (lava) inside the earth pushes through the crust
through the crust