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Deep Sea Trenches in tectaunique plates
The deepest waters are found in oceanic trenches, which plunge as deep as 35,000 feet below the ocean surface. These trenches are usually long and narrow, and run parallel to and near the oceans margins. They are often associated with and parallel to large continental mountain ranges. There is also an observed parallel association of trenches and island arcs. Like the mid-oceanic ridges, the trenches are seismically active, but unlike the ridges they have low levels of heat flow. Scientists also began to realize that the youngest regions of the ocean floor were along the mid-oceanic ridges, and that the age of the ocean floor increased as the distance from the ridges increased. In addition, it has been determined that the oldest seafloor often ends in the deep-sea trenches.

Island Arcs in tectaunique plates
Chains of islands are found throughout the oceans and especially in the western Pacific margins; the Aleutians, Kuriles, Japan, Ryukus, Philippines, Marianas, Indonesia, Solomons, New Hebrides, and the Tongas, are some examples.. These “Island arcs” are usually situated along deep sea trenches and are situated on the continental side of the trench.

These observations, along with many other studies of our planet, support the theory that underneath the Earth’s crust (the lithosphere: a solid array of plates) is a malleable layer of heated rock known as the asthenosphere which is heated by radioactive decay of elements such as Uranium, Thorium, and Potassium. Because the radioactive source of heat is deep within the mantle, the fluid asthenosphere circulates as convection currents underneath the solid lithosphere. This heated layer is the source of lava we see in volcanos, the source of heat that drives hot springs and geysers, and the source of raw material which pushes up the mid-oceanic ridges and forms new ocean floor. Magma continuously wells upwards at the mid-oceanic ridges (arrows) producing currents of magma flowing in opposite directions and thus generating the forces that pull the sea floor apart at the mid-oceanic ridges. As the ocean floor is spread apart cracks appear in the middle of the ridges allowing molten magma to surface through the cracks to form the newest ocean floor. As the ocean floor moves away from the mid-oceanic ridge it will eventually come into contact with a continental plate and will be subducted underneath the continent. Finally, the lithosphere will be driven back into the asthenosphere where it returns to a heated state.

Here is all you must now about mechanism in tectaunique plates. See you soon

Mid-Oceanic Ridges in tectaunique plates

The mid-oceanic ridges rise 3000 meters from the ocean floor and are more than 2000 kilometers wide surpassing the Himalayas in size. The mapping of the seafloor also revealed that these huge underwater mountain ranges have a deep trench which bisects the length of the ridges and in places is more than 2000 meters deep. Research into the heat flow from the ocean floor during the early 1960s revealed that the greatest heat flow was centered at the crests of these mid-oceanic ridges. Seismic studies show that the mid-oceanic ridges experience an elevated number of earthquakes. All these observations indicate intense geological activity at the mid-oceanic ridges.

Geomagnetic Anomalies in tectaunique plates
Occasionally, at random intervals, the Earth’s magnetic field reverses. New rock formed from magma records the orientation of Earth’s magnetic field at the time the magma cools. Study of the sea floor with magnometers revealed “stripes” of alternating magnetization parallel to the mid-oceanic ridges. This is evidence for continuous formation of new rock at the ridges. As more rock forms, older rock is pushed farther away from the ridge, producing symmetrical stripes to either side of the ridge. In the diagram to the right, the dark stripes represent ocean floor generated during “reversed” polar orientation and the lighter stripes represent the polar orientation we have today. Notice that the patterns on either side of the line representing the mid-oceanic ridge are mirror images of one another. The shaded stripes also represent older and older rock as they move away from the mid-oceanic ridge. Geologists have determined that rocks found in different parts of the planet with similar ages have the same magnetic characteristics.

The main features of tectaunique plate are:

• The Earth’s surface is covered by a series of crustal plates.
• The ocean floors are continually moving, spreading from the center, sinking at the edges, and being regenerated.
• Convection currents beneath the plates move the crustal plates in different directions.
• The source of heat driving the convection currents is radioactivity deep in the Earths mantle.

Advances in sonic depth recording during World War II and the subsequent development of the nuclear resonance type magnometer (proton-precession magnometer) led to detailed mapping of the ocean floor and with it came many observation that led scientists like Howard Hess and R. Deitz to revive Holmes’ convection theory. Hess and Deitz modified the theory considerably and called the new theory “Sea-floor Spreading”. Among the seafloor features that supported the sea-floor spreading hypothesis were: mid-oceanic ridges, deep sea trenches, island arcs, geomagnetic patterns, and fault patterns.

In the next article we will see in details all this aspects of tectaunique plates.

The work of Hess, Matthews and Vine, resulted in a new earth map, one that included tectaunique plate boundaries in addition to coastlines. Boundaries were drawn at mid-oceanic ridges and subduction zones.

Ongoing Evidence for Plate tectauniques

As The Himalayas turns out, started forming about 40 million years ago when the Indian Plate collided head-on with the Eurasian Plate, shoving and folding rocks that had formed below sea level into lofty peaks..

Today, much of the evidence concerning plate tectauniques is acquired with satellite technology. Through use of the global positioning system (GPS) and other satellite-based data collection techniques, scientists can directly measure the movement and speed of plates on the surface of the earth.

We no longer need to invoke a shrinking, wrinkled earth to explain the marine fossils at the top of the world.

Because the Indian Plate is still moving northward, the Himalayas are still rising at a rate of about 1 cm per year

Speeds range from 10 to 100 mm per year, confirming the long-held belief that plates move at a slow but constant rate.

Red = subduction zones. Blue = mid-ocean ridges,

Before Wegener, few had conceived of such a world. His continental drift theory was the first step in the development of plate tectaunique theory, the foundation upon which modern geology is built.

The earth is incredibly dynamic - mountain chains build and erode away, seas advance and recede, volcanoes erupt and go extinct - and these changes are all a result of the processes of plate tectauniques.

Continental-continental divergence causes a continent to separate into two or more smaller continents when it is ripped apart along a series of fractures. The forces of divergence literally tear a continent apart as the two or more blocks of continental crust begin slowly moving apart and magma pushes into the rift formed between them. Eventually, if the process of continental rifting continues, a new sea is born between the two continents. Rifting between the Arabian and African tectaunique plates formed the Red Sea in this way.

Continental-oceanic tectaunique plates. When continental and oceanic tectaunique plates converge, the oceanic tectaunique plate (which is denser) subducts below the edge of the continental tectaunique plate. Volcanoes form as result, but in this setting, the chain of volcanoes forms on the continental crust. This volcanic mountain chain, known as a volcanic arc, is usually several hundred miles inland from the tectaunique plate margin. The Andes Mountains of South America and the Cascade Mountains of North America are examples of volcanic arcs. No continental-oceanic divergent margins exist today. They are unlikely to form and would quickly become oceanic-oceanic divergent margins as seafloor spreading occurred.

Transform motion. In addition to convergence and divergence, transform motion may occur along tectaunique plate margins. Transform margins are less spectacular than convergent and divergent ones, and the type of tectaunique plates involved is really of no significance. As two rock tectaunique plates slide past one another at a margin, a crack or fault develops. The energy generated by the movement is often released in the form of an earthquake. The best known example of a transform tectaunique plate margin is the San Andreas Fault in California, where the Pacific and North American plates are in contact.

And it’s finally done for the tectaunique plates interactions

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Tectaunique plates can interact in one of three ways. They can move toward one another, or converge. They can move away from one another, or diverge. Or tectaunique plates can slide past one another, or transform. The boundaries where tectauniques plates meet are known as plate margins. The types of geologic activity that occur when two tectauniques plates interact is dependent on the nature of the plate interaction and of the margins. Tectauniques plate margins come in three varieties: oceanic-oceanic, continental-continental, and continental-oceanic.

Oceanic-oceanic tectaunique plates. When two oceanic plates converge, one of the tectaunique plates subducts or sinks underneath the other, forming a deep depression called an ocean trench. The subducted plate sinks downward into the mantle where it begins to melt. Molten rock from the melting tectaunique plate rises toward the surface and forms a chain of volcanic islands, or a volcanic island arc, behind the ocean trench. When oceanic tectaunique plates diverge, a ridge (mountain chain) develops and seafloor spreading occurs. Molten rock pushes up at the divergent margin, creating mountains and an expanding seafloor. Today, Europe and North America move about 3 inches (7.5 centimeters) farther apart every year as the Atlantic Ocean grows wider.

Continental-continental tectaunique plates. Continental-continental convergent tectaunique plates act quite differently than oceanic-oceanic plates. Continental crust is too light to be carried downward into a trench. At continental-continental convergent margins neither plate subducts. The two continental tectaunique plates converge, buckle, and compress to form complex mountains ranges of great height. Convergence of this sort produced the Himalayas when the Indian-Australian plate collided with the Eurasian plate.

Next time the last tectaunique plates interactions

Plate tectaunique, theory that the outer shell of the earth is made up of thin, rigid plates that move relative to each other. The theory of plate tectaunique was formulated during the early 1960s, and it revolutionized the field of geology. Scientists have successfully used tectaunique to explain many geological events, such as earthquakes and volcanic eruptions as well as mountain building and the formation of the oceans and continents.

Plate tectaunique arose from an earlier theory proposed by German scientist Alfred Wegener in 1912. Looking at the shapes of the continents, Wegener found that they fit together like a jigsaw puzzle. Using this observation, along with geological evidence he found on different continents, he developed the theory of continental drift, which states that today’s continents were once joined together into one large landmass.

Geologists of the 1950s and 1960s found evidence supporting the idea of tectaunique plates and their movement. They applied Wegener’s theory to various aspects of the changing earth and used this evidence to confirm continental drift. By 1968 scientists integrated most geologic activities into a theory called the New Global tectaunique, or more commonly, Plate tectaunique.

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Are they dangerous places to live?

Mountains, earthquakes, and volcanoes form where tectaunique plates collide. Millions of people live in and visit the beautiful mountain ranges being built by tectaunique plate collisions. For example, the Rockies in North America, the Alps in Europe, the Pontic Mountains in Turkey, the Zagros Mountains in Iran, and the Himalayas in central Asia were formed by tectaunique plate collisions. Each year, thousands of people are killed by earthquakes and volcanic eruptions in those mountains. Occasionally, big eruptions or earthquakes kill large numbers of people. In 1883 an eruption of Krakatau volcano in Indonesia killed 37,000 people. In 1983 an eruption-caused mudslide on Nevada del Ruiz in Columbia killed 25,000 people. In 1976, an tectaunique earthquake in Tangshan, China killed an astounding 750,000 people.
On the other hand, tectaunique earthquakes and tectaunique volcanoes occurring in areas where few people live harm no one. If we choose to live near convergent tectaunique plate boundaries, we can build buildings that can resist earthquakes, and we can evacuate areas around volcanoes when they threaten to erupt. Yes, convergent boundaries are dangerous places to live, but with preparation and watchfulness, the danger can be lessened somewhat.

Finally, love the tectaunique and it will love you

If you look at a tectaunique map, Africa seems to snuggle nicely into the east coast of South America and the Caribbean sea. In 1912 a German Scientist called Alfred Wegener proposed that these two continents were once joined together then somehow drifted apart. He proposed that all the continents were once stuck together as one big land mass called Pangea. He believed that Pangea was intact until about 200 million years ago.

The continents repartition is the tectaunique plates effect.