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Name: Matt
Status: Student
Grade: 6-8
Location: MI
Country: United States
Date: April 2006

I recently went snorkeling off the Yucatan Peninsula and the guide used a term to explain the "oily" appearance of the water where the fresh water met saltwater. Because I do not speak fluent Spanish, I missed the term. I understand the two types of water are different densities. He explained thermocline too. What word could be used for the density reaction?

I think you are talking about the "schlieren effect". Fluids of different densities refract light to different degrees. As two fluids of different density mix, an observer may see the two fluids mix in a sort of turbulent swirling pattern.

Christopher Perkins

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