Question

question: which ocean layer contains approximately 90 percent of earths seawater? answer options: select one of four pycnocline halocline and thermocline deep ocean mixed layer

Explanation:

To determine the ocean layer with ~90% of Earth’s seawater, we analyze each option:

• Pycnocline: A density - gradient layer, not a major seawater - holding layer.
• Halocline (salinity gradient) and thermocline (temperature gradient): These are transition layers, not the main seawater reservoir.
• Mixed layer: Shallow, mixed by wind, holds little of the total seawater.
• Deep ocean: The deep - sea layer (below the pycnocline/transition zones) contains approximately 90% of Earth’s seawater due to its vast volume and depth.

Answer:

Deep ocean