The world’s greatest earthquake belt, the circum-Pacific seismic belt, is found along the rim of the Pacific Ocean, where about 81 percent of our planet’s largest earthquakes occur. It has earned the nickname “Ring of Fire”.

The deepest earthquakes occur within the core of subducting slabs – oceanic plates that descend into the Earth’s mantle from convergent plate boundaries, where a dense oceanic plate collides with a less dense continental plate and the former sinks beneath the latter.

Most earthquakes occur along the edge of the oceanic and continental plates. The earth’s crust (the outer layer of the planet) is made up of several pieces, called plates.

Earthquakes occur along fault lines, cracks in Earth’s crust where tectonic plates meet. They occur where plates are subducting, spreading, slipping, or colliding. As the plates grind together, they get stuck and pressure builds up. Finally, the pressure between the plates is so great that they break loose.

At convergent plate boundaries, where two continental plates collide earthquakes are deep and also very powerful. In general, the deepest and the most powerful earthquakes occur at plate collision (or subduction) zones at convergent plate boundaries.

The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.

: tsunamis, earthquakes, volcanoes, rivers, valleys, mountain formation, faults…

They have also caused faults, cracks in the earth’s crust. Shifts along a fault can also cause earthquakes or violent jolts in the area around it. In coastal areas undersea earthquakes can cause huge waves known as Tsunamis to erupt. Plate tectonics cause folding of rock layers into mountains.

Heat and gravity are fundamental to the process Lithospheric plates are part of a planetary scale thermal convection system. The energy source for plate tectonics is Earth’s internal heat while the forces moving the plates are the “ridge push” and “slab pull” gravity forces.

There are four types of boundaries between tectonic plates that are defined by the movement of the plates: divergent and convergent boundaries, transform fault boundaries, and plate boundary zones.

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That plates are moving today can be demonstrated from earthquakes. The sense of relative movement of the earth on either side of seismically active faults can be determined from focal mechanisms – any for big-shallow earthquakes, can be directly measured from ground motion.

If two tectonic plates collide, they form a convergent plate boundary. Usually, one of the converging plates will move beneath the other, a process known as subduction. The new magma (molten rock) rises and may erupt violently to form volcanoes, often building arcs of islands along the convergent boundary.

When two oceanic plates collide, the denser plate is subducted and some material rises upward and forms an ISLAND. What happens when two continental plates collide? The continental crust is pushed together and upward to form large MOUNTAIN ranges. Ocean floor is pushed away from a midocean ridge to form new sea floor.

When two plates carrying continents collide, the continental crust buckles and rocks pile up, creating towering mountain ranges. When an ocean plate collides with another ocean plate or with a plate carrying continents, one plate will bend and slide under the other. This process is called subduction.

A subduction zone is also generated when two oceanic plates collide — the older plate is forced under the younger one — and it leads to the formation of chains of volcanic islands known as island arcs.

At convergent boundaries, plates collide with one another. The collision buckles the edge of one or both plates, creating a mountain range or subducting one of the plates under the other, creating a deep seafloor trench.

1 Answer. Oscar L. Continental plates contain less dense rocks than oceanic ones, so the continental plates are more buoyant and the oceanic plates will subduct uopn collision.

When two oceanic plates converge what determines which crust will submerge? the age, temperature, and density of the crust. Why do transform faults form? They form because the axis of seafloor spreading across the surface of the Earth cannot follow a straight line smoothly.

Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor.

What is the average rate of seafloor spreading in modern oceans? 5 centimeters (2 inches) per year.

List the four major features of subduction zones….Terms in this set (30)

• Oceanic lithosphere goes under the oceanic plate.
• Scraped sediments accumulate on upper plates.
• Igneous and metamorphic rocks form mountainous topography.