Unlike most subduction zones worldwide, there is no oceanic trench present along the continental margin in Cascadia earthquake of 1700.
42.
By contrast, far less helium-3 was found in volcanoes on continental margins, like those in the Andes and the Rockies.
43.
At that time the Atlantic continental margin was lifted up and formed a barrier between the basin and the sea.
44.
While the goechemical data includes elemental composition which is believed by some to be similar to an Andean type continental margin.
45.
Unlike most subduction zones worldwide, there is no deep oceanic trench present in the bathymetry of the continental margin in Cascadia.
46.
The oldest sediments were deposited on the flanks of a rifted continental margin, or passive margin that developed during Cambrian time.
47.
Around 280 Ma in the early Permian, the relative oceanic plate movement changed direction and the continental margin again became convergent.
48.
Turbidity currents responsible for wave generation are interpreted as originating from slope failures on the adjacent Venezuela, Guyana and Suriname continental margins.
49.
One of the most important discoveries is that canyons are major sources and sinks for sediment and organic matter on continental margins.
50.
The Rocas Verdes basin was filled with turbidites derived from the volcanic arc on its Pacific margin and partly from its continental margin.
