Where does the older crust go and what happens to it?
It is due to the process of subduction; oceanic crust tends to get colder and denser with age as it spreads off the mid-ocean ridges. It gets so dense, that it sinks in the upper mantle (subduction). This is like a giant recycling system for the oceanic lithosphere.
Where is the old crust typically destroyed?
Just as oceanic crust is formed at mid-ocean ridges, it is destroyed in subduction zones. Subduction is the important geologic process in which a tectonic plate made of dense lithospheric material melts or falls below a plate made of less-dense lithosphere at a convergent plate boundary.
Where might one go to find the oldest ocean crust?
Mediterranean Sea
What is in the deepest ocean?
Pacific Ocean
How long does it take to die from the bends?
Death only occurs in extreme cases. It can take hours or even days after a dive before sufferers become aware that they have decompression sickness. There are around 300 cases in the UK every year.
What happens if you swim straight up in the ocean?
Decompression sickness: Often called “the bends,” decompression sickness happens when a scuba diver ascends too quickly. Divers breathe compressed air that contains nitrogen. But if a diver rises too quickly, the nitrogen forms bubbles in the body. This can cause tissue and nerve damage.
What does getting the bends feel like?
The bends can affect almost any area of the body or any organ, including the lungs, heart, brain, joints, and skin. The most common signs and symptoms of the bends include joint pains, fatigue, low back pain, paralysis or numbness of the legs, and weakness or numbness in the arms.
What happens if the bends goes untreated?
Untreated bends cause damage! Failure to treat promptly and appropriately may lead to permanent impairment.
Why do they call it the bends?
Decompression sickness (DCS), known as ‘the bends’ because of the associated joint pain, is a potentially deadly condition caused by bubbles of nitrogen gas forming in the blood and tissues. It’s most common among divers using scuba tanks, but can affect free-divers and people at high altitude.
At what depth does the bends start?
About 40 percent of the bent divers made a single dive with only one ascent. The shallowest depth for a single dive producing bends symptoms was ten feet (three meters), with the bottom time unknown. However, most of the divers made several shallow dives and sometimes multiple ascents.
How do divers avoid the bends?
Ascend no faster than 30 feet per minute. Always perform a safety stop at 15 feet for three to five minutes. Remember, the ascent from safety stop to the boat is the most critical distance of your ascent, so go slow. Keep warm during and between dives.
What are the bends and how can they be prevented?
Avoid exercise 12 hours before a dive. Don’t fly immediately after a dive. Breathe normally during a dive. Make sure you are hydrated before a dive.