The mixture of molten rock, crystals and dissolved gases from the mantle is called magma. When magma erupts to the Earth's surface, it is called lava. Not all volcanic eruptions happen near the boundaries of tectonic plates. Some eruptions happen in the middle of the plates.These eruptions are caused by mantle streams called plumes. Mantle plumes are formed when hot magma rises beneath the thinner, or weaker, areas of the Earth's crust, creating 'hot spots'. Volcanic islands are formed when mantle plumes form at the bottom of the ocean.ome eruptions happen in the middle of the plates. These eruptions are caused by mantle streams called plumes. Mantle plumes are formed when hot magma rises beneath the thinner, or weaker, areas of the Earth's crust, creating 'hot spots'. Volcanic islands are formed when mantle plumes form at the bottom of the ocean.
Burst Fracture of the Lumbar Spine. General Considerations. Burst fractures result from axial loading most often secondary to motor vehicle accidents and falls. The axial load drives the intervertebral disk into vertebral body below. Usually produces a comminuted, vertical fracture through the vertebral body.
The Patella fracture may consist of a single crack across the kneecap or the kneecap may be broken into several pieces, in what is known as a 'stellate' fracture. In some instances a forceful contraction of the Quadriceps muscles can be enough to cause a fracture of the patella. This causes a horizontal crack across the knee cap, which makes it impossible for the patient to straighten their knee.