Robert Delaunay, 1912â13, Le Premier Disque, 134 cm (52.7 in.), Private collection. Abstract art uses a visual language of shape, form, color and line to create a composition which may exist with a degree of independence from visual references in the world. Western art had been, from the Renaissance up to the middle of the 19th century, underpinned by the logic of perspective and an attempt to reproduce an illusion of visible reality.
The magma here also cools into rock, but at a much slower speed than the lava at the surface. This gives crystals more time to grow, making the larger-grained rock known as gabbro. So thatâs why basalt is at the top of the ocean plate and gabbro is at the bottom. To put it in the form of the worldâs worst poem:
The difference between the two rock types is their grain size. Basalts are extrusive igneous rocks that cool quickly and have fine-grained crystals. Gabbros are intrusive igneous rocks that cool slowly and have coarse-grained crystals. Divergent boundary: In the oceanic crust, basalt forms near the surface at a divergent boundary, but gabbro forms at depth from slow crystallization.