Lesson: Learn about Plate Tectonics with Çağlar Söyüncü

Çağlar Söyüncü

Çağlar Söyüncü was born in May 1996 in Izmir, a major city on Turkey’s west coast. His first senior professional team was the Turkish second division Altmordu. He then played in the German Bundesliga for SC Freiburg before moving to Leicester City in England’s Premier League in 2018. He made his Turkish national team debut in 2016.

At just 24 years old, Söyüncü is regarded as a rapidly developing talent with a big future in the game.

Plate Tectonics

Plate tectonics is the study of the large-scale motion of the seven large plates of the earth’s crust and the movements of a larger number of smaller plates. The model builds on the concept of Continental Drift, an idea developed during the first decades of the 20th century.

The location where two plates meet is called a plate boundary. Plate boundaries are commonly associated with geological events such as earthquakes and the creation of topographic features like mountains, volcanoes, mid-ocean ridges, and oceanic trenches. The majority of the world's active volcanoes occur along plate boundaries, with the Pacific Plate's Ring of Fire being the most active and widely known today.

 Four types of plate boundaries exist with a fourth, mixed type, characterized by the way the plates move relative to each other. They are associated with different types of surface phenomena. The different types of plate boundaries are:

Constructive Boundaries

These occur where two plates move apart from one another. As the ocean plate splits, a ridge forms at the spreading centre, the ocean basin expands, and finally, the plate area increases causing many small volcanoes and/or shallow earthquakes. At zones of continent-to-continent rifting, constructive boundaries will cause a new ocean basin to form as the continent splits. As it spreads, the central rift collapses, and the ocean fills the basin. Active zones of mid-ocean ridges, for example, the Mid-Atlantic Rift and at its apex, Iceland, and the East Pacific Rise, and continent-to-continent rifting, like Africa's Rift Valley and Valley and the Red Sea, are examples of constructive boundaries.

Destructive Boundaries

 These occur where two plates slide toward each other to form a subduction zone (one plate moving underneath the other) At zones of ocean-to-continent subduction, for example the Andes mountain range in South America, the dense oceanic plate plunges beneath the less dense continental one. Earthquakes trace the path of the downward-moving plate as it descends and produces magma that leads to volcanoes. At zones of ocean-to-ocean subduction, for example, the Aleutian Islands in what is known as the Pacific Ocean’s Ring of fire, the motion causes earthquakes and a deep trench to form in an arc shape. The upper mantle of the subducted plate then heats up and magma rises to form curving chains of volcanic islands. Deep marine trenches are typically associated with subduction zones.

Collision Boundaries

Collisions between equal masses of continental granite-based plates, mean that neither mass is subducted, so the plate edges are compressed, folded, uplifted. The prime example of this phenomenon is the Himalayas.

Transformative Boundaries

These boundaries occur where two plates slide, grind past each other along fault lines where plates are neither created nor destroyed. Strong earthquakes can occur along transformative faults. The San Andreas Fault in California is a well-known example of a transformative boundary.

Ring of Fire

The Ring of Fire is a major area around the Pacific Ocean. In a large 25,000-mile horseshoe shape, it is associated with a nearly continuous series of oceanic trenches, volcanic arcs, volcanic belts and plate movements. It has more than 75% of the world's active and dormant volcanoes.

About 10% of the world's active volcanoes are found in Japan, which lies in a zone of extreme instability. As many as 1,500 earthquakes are recorded yearly, and magnitudes of 4 to 6 are not uncommon. Minor tremors occur almost daily in one part of the country or another, causing some slight shaking of buildings. Major earthquakes occur infrequently. Undersea earthquakes also expose the Japanese coastline to danger from tsunamis.

San Andreas Fault

The San Andreas Fault is a transformative fault that extends roughly for 750 miles through California in the United States. It forms the tectonic boundary between the Pacific Plate and the North American Plate. The fault divides into three segments, each with different characteristics and a different degree of earthquake risk. The slip rate along the fault ranges from 20 to 35 mm/yr.

The fault was identified in 1895 by Professor Andrew Lawson, who discovered the northern zone and named it after the surrounding San Andreas Valley. Following the 1906 San Francisco Earthquake, Lawson concluded that the fault extended all the way into southern California.