Basaltic Rocks Make Up Most Of The Sea Floor

Basaltic rocks make up most of the sea floor a true b false.

Basaltic rocks make up most of the sea floor.

Lava is molten rock at earth s surface. Older rocks will be found farther away from the spreading zone while younger rocks will be found nearer to the spreading zone. Basaltic rocks make up most of the. Granite and gabbro.

Intrusive igneous rocks are often characterized as coarse grained because. How does the eruption of mount st. These rocks have low concentrations of large ion lithophile elements lile light rare earth elements lree volatile elements and other highly incompatible elements. How does magma differ from lava.

It is composed of several layers not including the overlying sediment. Forces are applied equally in all directions. More than 90 of all volcanic rock on earth is basalt and the eruption of basalt lava is observed by geologists at about 20. Hydrothermal vents are common at spreading centers.

ˈ b æ s ɔː l t ˈ b æ s əl t is a mafic extrusive igneous rock formed from the rapid cooling of lava rich in magnesium and iron exposed at or very near the surface of a terrestrial planet or a moon. Obsidian exhibits a texture. The density is about 3 0 g cm3 composed mainly of the igneous rock basalt. The most voluminous volcanic rocks of the ocean floor are the mid oceanic ridge basalts which are derived from low potassium tholeiitic magmas.

Here convection currents deliver hot rock from deep in the mantle. Most of earth s basalt is produced at divergent plate boundaries on the mid ocean ridge system see map. The topmost layer about 500 metres 1 650 feet thick includes lavas made of basalt that is rock material consisting largely of plagioclase and pyroxene oceanic crust differs from continental crust in several ways. The average rock density is about 2 7 g cm3 composition is comparable to the felsic igneous rock granodiorite.

Basalts at oceanic divergent boundaries. Most of the rocks of the earth s crust are igneous although sedimentary rocks usually cover them. Basaltic rocks make up most of the sea floor. Confining pressure where.

The slow cooling at depth allows large crystals to grow. B ə ˈ s ɔː l t ˈ b eɪ s ɒ l t uk. Oceanic crust is about 6 km 4 miles thick. Helens compared to a typical eruption of hawaii a kilauea volcano.

Porosity is a measure of the volume of open space in rocks and unconsolidated geological materials such as alluvium and soils a. This hot rock melts as the divergent boundary pulls apart and the molten rock erupts onto the sea floor. Basalt is the most common type of igneous rock and it covers the ocean floor and thus exists. At a spreading center basaltic magma rises up the fractures and cools on the ocean floor to form new seabed.

Have a similar texture.