It looks like there are bubbles and serious height differences on the surface of the water. Is this really the case, or is there another explanation?

Answer
Dear Jan,
Indeed, the seas and oceans hide a seabed with a very pronounced relief. In fact, the longest mountain range on earth is underwater. These height differences are a direct result of the Earth’s internal structure and plate tectonics. In the appendix you will find an article in which the relief of the ocean floor is explained in a simple way. This will no doubt provide an answer to your question.
Kind regards,
dr. Hans Pirlet – marine geologist (Flemish Marine Institute)
Answered by
dr Hans Pirlet
(Marine) geology, marine and coastal research and policy
Wandelaarkaai 7 8400 Ostend
http://www.vliz.be
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