Geography
There are eight mountains over 400 m high, the tallest mountain is Mt. Hongtoushan (紅頭山) at 552 m. The rock on the island is volcanic tholeiite andesite, and volcanic explosive fragments. The volcano erupted in Miocene to Miocene period. It is part of the Luzon Volcanic Arc. Magma was formed from underthrusting oceanic crust under compression about 20 km deep. The andesite rock contains some visible crystals of pyroxene or amphibole. The geochemistry of the rock shows it is enriched in sodium, magnesium and nickel, but depleted in iron aluminium, potassium titanium and strontium.
Read more about this topic: Orchid Island
Famous quotes containing the word geography:
“The California fever is not likely to take us off.... There is neither romance nor glory in digging for gold after the manner of the pictures in the geography of diamond washing in Brazil.”
—Rutherford Birchard Hayes (1822–1893)
“Ktaadn, near which we were to pass the next day, is said to mean “Highest Land.” So much geography is there in their names.”
—Henry David Thoreau (1817–1862)
“Where the heart is, there the muses, there the gods sojourn, and not in any geography of fame. Massachusetts, Connecticut River, and Boston Bay, you think paltry places, and the ear loves names of foreign and classic topography. But here we are; and, if we tarry a little, we may come to learn that here is best. See to it, only, that thyself is here;—and art and nature, hope and fate, friends, angels, and the Supreme Being, shall not absent from the chamber where thou sittest.”
—Ralph Waldo Emerson (1803–1882)