The Tatun Volcano Group is found on the northern tip of Taiwan. Chihsingshan is the highest point of the volcanoes at 1120 meters. The volcanoes have formed the rounded shape of the northern cape of Taiwan. The volcanic rock also occur on Huaping Isle, Mienhua Isle, Pengchia Isle and Huangwei Isle just to the north of Taiwan. The rocks are aluminium rich andesite, tuff and breccia. The rocks are poor in sodium and magnesium, but rich in iron, potassium, rubidium and strontium and strong in rare earth elements. The magma was derived by melting of the underthrust sea plate behind the Ryukyu Volcanic Arc during the Pleistocene.