Ring-of-fire.pdf 1l6y2q

It is the term used to name the cluster of volcanoes

shaped like a ring. The Ring of Fire is a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur. In a 40,000 km (25,000 mi) horseshoe shape, it is associated with a nearly continuous series of oceanic trenches, volcanic arcs, and volcanic belts and plate movements.

The Ring of Fire is a direct result of plate tectonics and

the movement and collisions of crustal plates.

Subduction - is a geological process that takes place

at convergent boundaries of tectonic plates where one plate moves under another and is forced or sinks due to gravity into the mantle.

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. The Cocos Plate is being subducted beneath the Caribbean Plate, in Central America. 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 Peninsula 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.

More than 75% of the world’s volcanoes

About 90% of the world's earthquakes and 81% of the

world's largest earthquakes occur along the Ring of Fire. Including the most recently, the devastating quakes in Chile, Japan and New Zealand.

All but three of the world's 25 largest volcanic eruptions of the last 11,700 years occurred at volcanoes in the Ring of Fire.

Kilauea, which is considered the most active volcano in the world, is located in Hawaii. (Pacific Ring of Fire)

Most notable Earthquakes and Volcanic eruptions in the recent history

Christchurch Earthquake, New Zealand On 22 Feb 2011, a magnitude 6.3 earthquake caused severe damage in Christchurch and Lyttelton, killing 185 people and injuring several thousand

Mount Saint Helens, Washington, USA May 18, 1980 eruption of Mount Saint Helens. It has often been declared as the most disastrous volcanic eruption in United States history.

Mount Pinatubo, Philippines June 15, 1991, the volcano exploded as the second-largest volcanic eruption on Earth in the 20th century.

Mt. Fuji, Japan Mount Fuji may erupt violently if earthquake causes cracks inside.

Indonesia Japan Philippines Chile Mexico Russia USA New Zealand Alaska Canada

Plate tectonics is the theory that the outer rigid layer

of the earth (the lithosphere) is divided into a couple of dozen "plates" that move around across the earth's surface relative to each other, like slabs of ice on a lake. Volcanoes are associated with three types of tectonic structures: convergent plate boundaries and divergent plate boundaries and hot spot.

1. Pacific Ring of Fire 2. Mid-Ocean Ridge 3. Eurasian-Melanesian Mountain Belt

Largest earthquake zone U-shaped area Expanding all the way from west coasts of North and

South America, the east coast of Asia and the western pacific islands of the Philippines, Indonesia, New Guinea, and New Zealand.

Major area in the Pacific Ocean Large earthquake, Volcanic Eruptions occurs Oceanic trenches, volcanic arcs, and volcanic belts or

plate movements

Underwater mountain system Submerged deep in the ocean Geologically active Divergent Plate Boundary Oceanic crust pulling away from both sides of the

ridge Causes stress in the rocks

Pacific Island through Asia and Southern Europe and

into northwestern Africa. Convergent plate boundaries Results of collision between tectonic plates Causes mountains and earthquake

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Major fault lines in the Philippines

Marikina Valley Fault-This fault is also known as the

Valley Fault System and is divided into two segments, the West Valley Fault and the Eastern Valley Fault. Philippines.

1. Montalban 2. San Mateo 3. Marikina 4. Pasig 5. Taguig 6. Muntinlupa 7. San Pedro 8. Biñan 9. Carmona 10. Santa Rosa 11. Calamba 12. Tagaytay 13. Oriental Mindoro

-Southern of Mindanao Fault-The two major fault

zones that are most dangerous in this area are the Sulu Trench in the Sulu Sea and the Cotabato Trench, a region of subduction that crosses the Celebes Sea and the Moro Gulf in Southern Mindanao.

Central Philippine Fault-This system of faults is found

to be the locus of great earthquakes and it is known to be a transition zone with slow slip and creep activity. This is based on the analysis and correlation of seismic historic data and detailed documentation of recent seismic events in the region. Based on this study the Guinyangan fault is defined to be the northern locked portion with recurrence interval of as short as 65 years.

The 1,200-km-long Philippine fault zone

(PFZ) is a major tectonic feature that transects the whole Philippine archipelago from northwestern Luzon to southeastern Mindanao. This arc-parallel, left-lateral strike slip fault is divided into several segments and has been the source of largemagnitude earthquakes in recent years.

 such as the 1973 Ragay Gulf earthquake (M 7.0), 1990

Luzon earthquake (Mw 7.7) (Figure 1), and 2003 Masbate earthquake (Ms 6.2). The high seismic risk posed by this fault zone requires a large-scale active faults map, a fundamental data set for seismic hazard mitigation

Philippine fault zone maps: 1. Northern Luzon 2. Central Luzon 3. Infanta 4. Guinayangan 5. Bondoc Peninsula 6. Masbate Island 7. Leyte Island 8. Eastern Mindanao

 is an inter-related system of faults throughout the whole of

the Philippine Archipelago, primarily caused by tectonic forces compressing the Philippine into what tectonic geophysicists call the Philippine Mobile Belt  The Philippine Mobile Belt is composed of a large number of accretionary blocks and strips. Most strips are long and narrow like the Zambales ophiolites which is at least 400 km long and 50 km wide.  The strips generally run north-south and the zones of convergence are usually demarkated by fault lines. The Philippine Mobile Belt is compressed on the west by the Eurasian Plate and two arms of the Sunda Plate, and on the east by the Philippine Sea Plate.

These tectonic plates have compressed and lifted parts

of the Philippines causing extensive faulting, primarily on a north-south axis. The main fault runs most of the length of the Philippines and is called the Philippine Fault.

In northern Luzon, the fault has become braided and

is no longer single. All faults in the Philippines are inter-related by the tectonic forces causative of the Philippine Mobile Belt, or its tectonic induced Volcanism.