The Story Of The Island

By+Tu+Qiang

Discovering

the island again

In July, 1834, Darwin went for inspection along with the Bigger ship. During the inspection, different phenomena kept refreshing Darwins understanding of the earth. At Verde of San Diego, he found that there was a strip of white settled layer with bare coral and shell fragments high up in a volcanic rock cliff, this discovery brought about brand new angle of view for him on thinking about the island geologic history. In the next journey, Darwin had more discoveries. In Patagonia, he saw stratums mixed with roundstones and shells spreading along the level up. After the chile earthquake, he found the earthquake elevated the land, piling the mussel bed base on the tide. High on the Andes, he found fossil trees standing on a beach, with masses of seashells scattering around. After exploring the Cocos (keeling) islands, he inferred that these coral islands were formed above the submerged volcanoes.

In 1840, Darwin put forward the island evolution model of volcano to coral islands, he marked out fringing reef, barrier reef and atoll according the relations between reefs and water front.

Afterwards, the Challenger ship (1870-1876) of England and other countrys research ships also began the investigation of the ocean floor.In the aspect of speculation about the formation of islands, the concepts of continental island and oceanic island gradually came into being.

By the 1960s, after the plate tectonics came in, a large number of geophysical and deepwater drilling data revealed the forming and evolution processes of the constructions and geomorphic of continental margin, oceanic basin and mid-ocean ridge. These new data and discoveries brought about people new understanding of the cause of forming oceanic islands.