GEOLOGIC PROCESSES THAT OCCUR ALONG DIVERGENT AND TRANSFORM FAULT BOUNDARIES | SCIENCE 10 - Week 6

Summary

This educational video explores the geological processes at divergent and transform plate boundaries. It explains how divergent boundaries, both oceanic and continental, lead to the formation of mid-ocean ridges and rift valleys, respectively, with examples like the Mid-Atlantic Ridge and the African Rift Valley. Transform boundaries, characterized by horizontal plate movement, result in strike-slip faults like the San Andreas Fault. The video uses engaging activities and illustrations to clarify these concepts, making complex geology accessible.

Takeaways

• 🌏 The video discusses the geologic processes that occur at divergent and transform plate boundaries.
• 🔍 The lesson begins with an activity to analyze photographs of rift valleys and oceanic ridges to understand the effects on Earth's crust.
• 🌋 Divergent plate boundaries occur when plates pull away from each other, leading to the formation of geologic features like rift valleys and mid-ocean ridges.
• 🌊 Mid-ocean ridges are underwater mountain ranges formed by the movement of oceanic plates and are associated with seafloor spreading.
• 🌐 The Mid-Atlantic Ridge is a notable example of a mid-ocean ridge, with the island of Iceland situated atop it.
• 📏 The spreading rate at mid-ocean ridges is typically between 2 to 20 centimeters per year.
• 🏞️ Continental rifting, a type of divergent boundary, can lead to the formation of new ocean basins over millions of years, as seen in the African Rift Valley and the Red Sea.
• ⛔️ Transform fault boundaries occur when plates slide horizontally past each other without creating or destroying crust, resulting in features like the San Andreas Fault.
• 🏔️ Strike-slip faults, such as the San Andreas Fault, are characterized by horizontal movement and can lead to earthquakes when pressure builds up and overcomes friction.
• 🌉 Oceanic fracture zones are formed by transform fault boundaries on the seafloor, creating large valleys or trenches that connect spreading oceanic ridges.

Q & A

What are the two main types of divergent plate boundaries mentioned in the script?

The two main types of divergent plate boundaries mentioned are oceanic-oceanic divergence, which leads to the creation of mid-ocean ridges, and continental-continental divergence, also known as continental rifting.

What is the process of seafloor spreading and how does it form new oceanic crust?

Seafloor spreading occurs when oceanic plates move apart at mid-ocean ridges. Lava rises, erupts, and cools, and as more lava erupts, it pushes the original seafloor outward, forming new oceanic crust.

What is a mid-ocean ridge and where is a common example located?

A mid-ocean ridge is an underwater mountain range formed by oceanic plates moving apart. A common example is the Mid-Atlantic Ridge, which stretches around the world.

How does the spreading rate at the Mid-Atlantic Ridge compare to other mid-ocean ridges?

The spreading rate at the Mid-Atlantic Ridge is relatively fast, at 2 to 20 centimeters per year, which is typical for mid-ocean ridges.

What is the result of continental rifting and how does it relate to the formation of rift valleys and new ocean basins?

Continental rifting leads to the formation of rift valleys and eventually new ocean basins as the molten rock from the mantle erupts along the opening, forming new crust and causing the continent to split apart.

What are the geological features formed by transform fault boundaries?

The geological features formed by transform fault boundaries include oceanic fracture zones on the seafloor and faults, typically known as strike-slip faults, when they occur on land.

How do transform fault boundaries differ from divergent plate boundaries in terms of crustal activity?

Transform fault boundaries differ from divergent plate boundaries in that they involve horizontal sliding of plates past each other without creating or destroying crust, making them conservative boundaries.

What is the San Andreas Fault and how is it related to plate tectonics?

The San Andreas Fault is a transform fault boundary formed by the relative sliding motion of the North American Plate and the Pacific Plate. It is an example of a strike-slip fault where the plates slide horizontally past each other.

What effect do earthquakes have on the geological features formed by divergent and transform boundaries?

Earthquakes can cause changes in the geological features formed by both divergent and transform boundaries. In divergent boundaries, they can be associated with the movement of plates and the creation of new crust, while in transform boundaries, they result from the release of built-up pressure due to friction between sliding plates.

How do the geological processes at divergent and transform boundaries contribute to the Earth's dynamic crust?

The geological processes at divergent and transform boundaries contribute to the Earth's dynamic crust by continuously reshaping its surface through the creation of new crust at divergent boundaries and the rearrangement of existing crust at transform boundaries.