Pacific Ring of Fire

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The Ring of Fire redirects here. To see other uses, go to Ring of Fire (disambiguation).

The Pacific Ring of Fire

The Pacific Ring of Fire is an area of frequent earthquakes and volcanic eruptions encircling the basin of the Pacific Ocean. In a 40,000 km horseshoe shape, it is associated with a nearly continuous series of oceanic trenches, island arcs, and volcanic mountain ranges and/or plate movements. It is sometimes called the circum-Pacific belt or the circum-Pacific seismic belt.

Ninety percent of the world's earthquakes and 81% of the world's largest earthquakes occur along the Ring of Fire. The next most seismic region (5–6% of earthquakes and 17% of the world's largest earthquakes) is the Alpide belt which extends from Java to Sumatra through the Himalayas, the Mediterranean, and out into the Atlantic. The Mid-Atlantic Ridge is the third most prominent earthquake belt. [1] [2].

The Ring of Fire is a direct result and consequence of plate tectonics and the movement and collisions of crustal plates [3]. The eastern section of the ring is the result of the Nazca Plate and the Cocos Plate being subducted beneath the westward moving South American Plate. A portion of the Pacific Plate along with the small Juan de Fuca Plate are being subducted beneath the North American Plate. Along the northern portion the northwestward moving Pacific plate is being subducted beneath the Aleutian Islands arc. Further west the Pacific plate is being subducted along the Kamchatka—Kurile Islands arcs on south past Japan. The southern portion is more complex with a number of smaller tectonic plates in collision with the Pacific plate from the Mariana Islands, the Philippines, Bougainville, Tonga, and New Zealand. Indonesia lies between the Ring of Fire along the northeastern islands adjacent to and including New Guinea and the Alpide belt along the south and west from Sumatra, Java, Bali, Flores, and Timor. The famous and very active San Andreas Fault zone of California is a transform fault which offsets a portion of the East Pacific Rise under southwestern United States and Mexico. The motion of the fault generates numerous small earthquakes, at multiple times a day, most of which are too small to be felt. [4] [5]

Although little known to the general public, British Columbia and the Yukon Territory is home to a large region of volcanoes and volcanic activity in the Pacific Ring of Fire. The volcanism in the regions is due to extensional cracking, faulting and rifting of the North American Plate, as the Pacific Plate grinds and slides past the Queen Charlotte Fault, unlike the subduction of the Pacific Plate that produces the volcanoes in Japan, Philippines and Indonesia. The region has Canada's largest volcanoes, much larger than the minor stratovolcanoes found in the Canadian portion of the Cascades Arc. Mount Edziza is a huge volcanic complex that erupted several times in the past several thousand of years, which has formed several cinder cones and lava flows. Hoodoo Mountain is a tuya in northwestern British Columbia, which has had several periods of subglacial eruptions. The oldest eruptions occurred about 100,000 years ago and the most recent being about 7000 years ago. Hoodoo Mountain is also considered to be active and could erupt in the near future. The nearby Tseax River Cones and Lava Fork Valley produced some of Canada's youngest lava flows, that are about 150 years old. The lava flows are about 22 km long.

The southern end of the Pacific Ring of Fire is the continent Antarctica, which includes many large volcanoes. The makeup and structure of the volcanoes in Antarctica change largely from the other places around the ring. In contrast, the Antarctic Plate is almost completely surrounded by extensional zones, with several mid-ocean ridges which encircle it, and there is only a small subduction zone at the tip of the Antarctic Peninsula, reaching eastward to the remote South Sandwich Islands. The most well known volcano in Antarctica is Mount Erebus, which is also the world's southernmost active volcano.

The December 2004 earthquake just off the coast of Sumatra was actually a part of the Alpide belt.^{[citation needed]}

Countries of the Pacific Ring of Fire [6]

• Argentina • Belize • Bolivia • Brazil • Brunei • Canada • Colombia • Chile • Costa Rica • Ecuador • East Timor • El Salvador • Micronesia • Fiji • Guatemala • Honduras • Indonesia • Japan • Kiribati • Malaysia • Mexico • New Zealand • Nicaragua • Palau • Papua New Guinea • Panama • Peru • Philippines • Russia • Samoa • Solomon Islands • Tonga • Tuvalu • United States •

Oceanic Trenches of the Pacific Ring of Fire
• Aleutian Trench • Bougainville Trench • Kermadec Trench • Izu Bonin Trench • Japan Trench • Kurile Trench • Mariana Trench • Middle America Trench • Peru-Chile Trench • Philippine Trench • Ryukyu Trench • Tonga Trench • Yap Trench •

Tectonic Plates of the Pacific Ring of Fire
• Antarctic Plate • Australian Plate • Caribbean Plate • Cocos Plate • Eurasian Plate • Explorer Plate • Gorda Plate • Juan de Fuca Plate • Nazca Plate • North American Plate • Pacific Plate • Philippine Plate • Rivera Plate • South American Plate •