TRANSFORM BOUNDARY CRACK

Some of these events may be triggered by earthquakes from the principal boundary. However, strike-slip seismic events also occur in the second valley and elsewhere in the deformed zone. One of the valleys is seismically highly active and constitutes the present-day principal transform boundary. Examples are the 750-km-long, 120-km-wide Andrew Bain transform on the Southwest Indian Ridge, and the Romanche transform, where the Mid-Atlantic Ridge is offset by a lens-shaped, similar to900-km-long, similar to100-km-wide sliver of deformed lithosphere bound by two major transform valleys. However, we define here a new class of oceanic transform boundaries, with broad complex multifault zones of deformation, similar to some continental strike-slip systems. See if you can figure out the plate movements and geologic events occurring at real-world locations.Oceanic transform plate boundaries consist of a single, narrow (a few kilometers wide) strike-slip seismic zone offsetting two mid-ocean ridge segments. Many scientists believe that the San Andreas Fault is due to unleash another large earthquake - a 'big one' - in the coming decades. While many are small and cause only minor trembling, the San Andreas Fault has also been the site of major events: the 1857 Fort Tejon earthquake, the 1906 San Francisco earthquake and fire, and the 1989 Loma Prieta earthquake.

As the two plates grind past each other - the Pacific Plate moving northwest and the North American Plate moving southeast - the motion produces numerous earthquakes along the fault.

It is located at the boundary between the Pacific and North American plates and runs roughly 800 miles (1,300 km) through Northern and Southern California. The best-studied strike-slip fault is the San Andreas Fault in California. The motion of the plates at a transform boundary has given this type of fault another name - a strike-slip fault. At this point, water from the ocean will rush in, forming a new sea or ocean basin in the rift zone. Eventually, the widening crust along the boundary may become thin enough that a piece of the continent breaks off, forming a new tectonic plate. Early in the rift formation, streams and rivers flow into the low valleys and long, narrow lakes can be created. As the crust widens and thins, valleys form in and around the area, as do volcanoes, which may become increasingly active. This rift is a dropped zone where the plates are pulling apart. When two continental plates diverge, a valleylike rift develops. The magma also spreads outward, forming new ocean floor and new oceanic crust. Magma then oozes up from the mantle to fill in the space between the plates, forming a raised ridge called a mid-ocean ridge.

TRANSFORM BOUNDARY CRACK

As plates made of oceanic crust pull apart, a crack in the ocean floor appears. But if these huge masses of crust are moving apart, what happens in the space left between them?ĭivergent boundaries in the middle of the ocean contribute to seafloor spreading. Slip, Slide, & Collide Divergent Boundaries - Spreading PlatesĪt divergent boundaries, tectonic plates are moving away from each other.

Transform boundary