Iceland's Volcanoes
Iceland is located on the boundary of the North American and Eurasian plate. It lies on a divergent boundary so the North American and Eurasian plate are moving away from each other. It also lies on a large volcanic hot spot. This is the reason why there are volcanoes in Iceland, the plates are moving a part and magma is rising from the upper mantle and is creating new rock. Volcanoes are created through this process.
The San Andreas Fault
The San Andreas Fault is one of the most recognizable landform in the world. It extends from northern California southward to Cajon Pass (near San Bernardino). The fault lies on the boundary of the Pacific plate and the North American plate. These two plates have a transforming (sliding) boundary and this is the cause of the fault. The Pacific plate moves north while the North American plate moves south. The fault stretches for about 1 300 km and about 16 km deep. The fault has also been the cause of many earthquakes and shifts in the plates. In the 1906 earthquake in the San Francisco region, an earthquake struck. Roads, fences and trees that crossed the fault had moved several meters. This shows how the two plates are sliding past each other. Even now, there are thousands of small earthquakes along the fault line that are experienced every year.
The Himalayas Mountains
The Himalayas Mountains were created millions of years ago. It lies at the boundary of the Indo-Australian and Eurasian plate. Millions of years ago, the Indo-Australian plate was pushed northwards towards the Eurasian plate by convection currents. The same happened to the Eurasian plate except that it was pushed southward by the convection currents. When the two plates met, they pushed against each other, forcing each plate upwards. The two plates are forced upwards because they are similar in density so neither plate is subducted beneath the other (some parts may be subducted but not as much as a continental-oceanic convergence. Even now, this process has not stopped. The Indo-Australian and Eurasian plate continue to push against each other today and pushing Tibet upwards. The Himalayas continue to rise about 2 cm each year.