Basaltic Rocks Make Up Most Of The Sea Floor True False

Learn more about basalt in this article.

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

Have a similar texture. One magma can produce several different igneous rocks having different mineral compositions. The pressures at depth causes them to have a rough texture d. Here convection currents deliver hot rock from deep in the mantle.

Oceanic crust is the uppermost layer of the oceanic portion of a tectonic plate it is composed of the upper oceanic crust with pillow lavas and a dike complex and the lower oceanic crust composed of troctolite gabbro and ultramafic cumulates. Most of earth s basalt is produced at divergent plate boundaries on the mid ocean ridge system see map. This hot rock melts as the divergent boundary pulls apart and the molten rock erupts onto the sea floor. True t f lignite and bituminous coals are sedimentary rocks.

The slow cooling at depth allows large crystals to grow. True t f glassy igneous rocks form when magma cools too fast for mineral grains to grow. False t f slate is associated with high grade metamorphism. 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. False t f the particles in breccia are primarily silt sized. The crust overlies the solidified and uppermost layer of the mantle the crust and the solid mantle layer together constitute oceanic lithosphere.

It is thinner denser younger and of different. The tholeiitic and the alkali basalts. Granite and gabbro. Basalt extrusive igneous volcanic rock that is low in silica content dark in color and comparatively rich in iron and magnesium.

Oceanic crust is about 6 km 4 miles thick. Basalt is clearly the most common volcanic rock on earth and basaltic rocks including gabbro diabase and their metamorphosed equivalents are the most common rocks in the crust 2 basalt is also common on the moon and other rocky planets of the solar system. Basaltic rocks make up most of the sea floor. The density is about 3 0 g cm3 composed mainly of the igneous rock basalt.

Continental exceeds 70 kilometers under some mountainous regions while oceanic crust ranges from 3 to 15 kilometers. Basalt is a major rock type that occurs in virtually every tectonic setting. Intrusive igneous rocks are often characterized as coarse grained because. Basalts may be broadly classified on a chemical and petrographic basis into two main groups.

It is composed of several layers not including the overlying sediment. Small holes from escaping gases leave them rough and course c.