![]() Most of the earthquakes and volcanoes around the Pacific ocean basin-a pattern known as the “ring of fire”-are due to the movement of tectonic plates in this region. The term fault is used to describe the boundary between tectonic plates. Earthquakes and volcanoes are the direct result of the movement of tectonic plates at fault lines. The upper mantle, in turn, floats on a denser layer of lower mantle that is much like thick molten tar.Įach tectonic plate is free-floating and can move independently. ![]() Both types of crust rest atop solid, upper mantle material. It is composed of two distinctly different types of material: the less-dense continental crust and the more-dense oceanic crust. Recall that the crust is the solid, rocky, outer shell of the planet. The earth’s crust is broken into separate pieces called tectonic plates (Fig. ![]() ![]() Image courtesy of United States Geological Survey ( USGS) ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |