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 where they do because of the position of the crust over a plate boundary or a 'hot spot' in the Earth's mantle.olcanoes usually occur where there are collision of the tectonic plates. There are 52 tectonic plates which either pull (gap and crack) or push (volcano). Volcanoes are actually tectonic plates which have magmas beneath their outer surface.