Basaltic Magma Has A Lower Silica Content Than Granitic Magma
Measurements of the basaltic magmas at kilauea vary from 750 to over 1200 those at vesuvius vary nearly as much.
Basaltic magma has a lower silica content than granitic magma. As rock begins to melt the minerals with the lowest melting temperatures are the first to melt. Lower temperature magmas have higher viscosity than higher temperature magmas viscosity decreases with increasing temperature of the magma. Granitic magma is higher in silica than basaltic magma. True false the higher the silica content in lava the higher the lava s resistance to flow.
Rhyolitic magma is generated along convergent plate boundaries where oceanic lithosphere descends into the mantle at subduction. Due in part to the lower temperature felsic magma is much more viscous than mafic magma meaning it is much thicker and more resistant to flowing. What magma produces very explosive eruptions. Solidify magma with a high water content has a greater tendency to in the crust compared with a magma with a lower water content.
Magmas have a high silica content and a high viscosity. Because of its low viscosity and gas content basaltic magma is geberally the least explosive of the common magma types. Recall that igneous rocks are composed of a mixture of minerals and therefore tend to melt over a temperature range of at least 200 c nearly 400 f. Low magmas have a low silica content and a low viscosity.
As the rising magma moves slowly up through the continental crust of the overriding plate however two things may occur to increase significantly the silica content of the magma. Thus basaltic magmas tend to be fairly fluid low viscosity but their viscosity is still 10 000 to 100 0000 times more viscous than water. It has an intermediate density cooling point and viscosity compared with other types of magma. Rhyolitic magmas have lower temperatures than basaltic magmas.
Typical granitic magma contains silica water than typical basaltic magma. Basaltic magma has low high viscosity and contains little lots of gas. Rhyolitic magmas tend to have even higher viscosity ranging. The rising subduction zone magma is probably basaltic in composition and is formed by the partial melting of mantle rocks.
Describe how partial melting of the mantle rock peridotite can generate a basaltic mafic magma. Basaltic magmas have a high low silica content and a high low viscosity.