If a substantial amount of calcium is discovered, coronary artery disease may be likely. A CT coronary angiogram, in which you receive a contrast dye injected intravenously during a CT scan, also can generate images of your heart arteries.
At converging plate boundaries, two situations are possible. First, both volcanoes and earthquakes form where one plate sinks under the other. This process, called subduction, takes place because one plate is denser than the other. The denser plate, which invariably has oceanic crust on its top, does the sinking. Second, only earthquakes occur when two plates collide (obduct), building a mountain range.
Volcanoes occur at divergent plate boundaries because of the new crust formed by solidifying of magma on the ocean bed which is very weak so the heat and pressure from the magma chamber will become too high to handle and there will be an eruption. Volcanoes form where the earth's crust is thin an the magma can flow to the surface easier.