Both are made up of minerals from the silicate group, so both have large amounts of silicon and oxygen. Both will hurt if you drop a big piece on your toe. But there are several important differences, too. These differences help define and explain how the earth works.
Granite is great stuff! Not only is it my personal favorite, it is without a doubt the most common rock type on the continental land masses. Yosemite Valley in the Sierra Nevada and Mt. Rushmore are two notable examples of granitic rocks. But granitic "basement rock" can be found just about everywhere east of the Rockies if you're willing to dig through the dirt and sedimentary rocks at the surface.
Granite is intrusive, which means that the magma was trapped deep in the crust , and probably took a very long time to cool down enough to crystallize into solid rock.
This allows the minerals which form plenty of time to grow, and results in a coarse-textured rock in which individual mineral grains are easily visible. An intermediate form between granite and diorite. High silica content acidic Gabbro. Medium silica content. A layer of gabbro is found in the ocean crust, unerneath the basalt layer 0. The lunar highlands have many gabbros made largely of potassium feldspar - also known as plagioclase Peridotite.
Small crystals. Medium silica content intermediate. A fine-grained volcanic rock of granitic composition. Free learning resources from arts, cultural and heritage organisations. Igneous Rocks: Examples and Uses This page reveals the different ways in which types of igneous rock can be used. Granite Granite. Younger basalt flows will have fewer craters.
Olympus Mons is a shield volcano on Mars. It, like most other volcanic features on Mars, was formed from basaltic lava flows. It is the highest mountain on Mars and is the largest known volcano in our solar system. Basalt-Forming Environments: This map shows the location of oceanic divergent boundaries and hotspots. These are locations where large volumes of basalt have been formed.
Map copyright by Geology. Igneous rock composition chart: This chart shows that basalt is typically composed of pyroxenes, plagioclase, micas, and amphiboles. Most of the basalt found on Earth was produced in just three rock-forming environments: 1 oceanic divergent boundaries , 2 oceanic hotspots , and 3 mantle plumes and hotspots beneath continents.
The images on this page feature some of these basalt-forming environments. Sea floor pillow basalts on the Juan de Fuca Ridge, a divergent plate boundary located about miles kilometers west of the Washington-Oregon coast. This lava flow, produced by a fissure eruption, was about five years old when the photograph was taken.
Multiple locations where hot lava streams into the ocean can be seen in this image along with a red-hot lava flow traversing the lava field. This photo shows the enormous extent of the flows. They extend from the shoreline up to the horizon. USGS image. Most of Earth's basalt is produced at divergent plate boundaries on the mid-ocean ridge system see map. Here convection currents deliver hot rock from deep in the mantle. This hot rock melts as the divergent boundary pulls apart, and the molten rock erupts onto the sea floor.
These submarine fissure eruptions often produce pillow basalts as shown in the image on this page. The active mid-ocean ridges host repeated fissure eruptions. Most of this activity is unnoticed because these boundaries are under great depths of water. At these deep locations, any steam, ash, or gas produced is absorbed by the water column and does not reach the surface.
Earthquake activity is the only signal to humans that many of these deep ocean ridge eruptions provide. However, Iceland is a location where a mid-ocean ridge has been lifted above sea level.
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