These occur in regions where a mid-ocean ridge is being subducted. The collision of tectonic plates can result in earthquakes, volcanoes, the formation of mountains, and other geological events. Igneous rock (derived from the Latin word ignis meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic.Igneous rock is formed through the cooling and solidification of magma or lava.. Two different series of rocks are found in some volcanic chains. In this case, granite batholiths underlie the great composite volcanoes and consist of rocks ranging from basalt through andesite to dacite and rhyolite. 1. Classification. It appears that basalt is common on Mars as well. The stable interiors of South Africa and Siberia have widespread occurrences, but these pipes also are found in North America, Australia, Brazil, and India. Oceanic trenches outline the junction of the colliding plates, but the igneous activity takes place on the overriding plate along a line at least about 100 kilometres above the subducting plate (see Figure 3). Igneous Rocks of the Convergent Margins The convergent plate margins are the most intense areas of active magmatism above sea level at the present time. The large shield volcano Olympus Mons must have been formed from eruptions of fluid basalt flows. Igneous Rocks •The production of magma and igneous activity is associated with plate tectonic boundaries, hot spots, and continental rifts •Magmas accumulate in magma chambers at depths of a few kilometers below divergent boundaries and at tens of kilometers below convergent boundaries. In North America, near Murfreesboro, Arkansas, individuals can pay a fee to search for diamonds in the Prairie Creek kimberlite pipe located in the Crater of Diamonds State Park. Identify the igneous rock: QUESTION 15 Sample 18: How did this rock form? At many convergent boundaries a subduction zone is formed which drives crust down toward the mantle where the rock is melted and turned to igneous rock. Major-element compositions of Cenozoic adakitic rocks at convergent plate boundaries (intra-oceanic arcs, continental arcs, continental-margin island arcs, and continental collisional zones). Basalt an igneous rock flows to the surface at divergent boundaries such as mid ocean ridges, and cracks in the earth caused by plate movements. Three-dimensional diagram showing crustal generation and destruction according to the theory of plate tectonics; included are the three kinds of plate boundaries—divergent, convergent (or collision), and strike-slip (or transform). At convergent plate boundaries sedimentary rock sinks into the Earth's outer core, and the intense pressure reorganizes matter to form large igneous rock materials. The X-ray fluorescence analyses performed by the Vikings 1 and 2 landers showed that the rocks are basaltic. As a liquid rock cools, first one mineral and then another achieves saturation and precipitates, each extracting specific elements in the process. found among igneous pegmatites and carbonatite rocks. Igneous rocks form from magmas, and most magmas are associated with plate tectonics. A clear picture about convergent plate boundaries is envisaged from geophysical studies that include gravity surveys, measurements of heat flow and seismic-reflection profiles.In addition, geochemical and trace element studies of the igneous rocks found at these boundaries tell the tale of their generation, migration, assimilation and differentiation. This rift system stretches southward from the Red Sea–Gulf of Aden to Lake Victoria. In this case, granite batholiths underlie the great composite volcanoes and consist of rocks ranging from basalt through andesite to dacite and rhyolite. 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