I mean, its hard to look past a flood story and not think "well, maybe we really will find Atlantis one day, zug zug .."
Not to mention .. The idea of finding tsunami/cataclysm victims by looking for diatoms is absolutely fascinating.
 - https://en.wikipedia.org/wiki/Stanisław_Szukalski
"A struggle ensued; the ocean receded and rose again. Many canoes were flung into trees and many people were killed."
Across the pacific, the Japanese have a similar story about a giant catfish causing earthquakes.
Its a crackpot theory, but I do wonder where things are going with all these scientists having interests in flood events and other crazy weather conditions.
If a victim drowns, is it feasible diatoms can move through the bloodstream into marrow? Drowning = death = no blood flow.
1. Diatoms would/could travel through deceased blood VESSELS as tubes or plumbing channels, but unlikely the active blood stream. And certainly not en masse, as if invading in seconds or minutes.
2. Diatoms are ordinarily destected in THE LUNGS of the deceased, upong forensic investigation. Why the lungs? BECAUSE THAT'S THE PART THAT DROWNS.
Lungs filling with water results in drowning. Sea water contains diatoms. Drowning at sea puts diatoms in the lungs. Drowning does not really put water anywhere else. This means drowning won't put diatoms anywhere water won't go.
So, even if you chop someone in half, and throw them into the sea, the diatoms aren't hell bent on going all creepy crawly and getting into the blood stream. But, after the person dies, and swish, swish, veins and arteries become rinsed out, and bones cracked in half show their interior to the ocean, yes blood vessels might incidentally become home to diatoms, in the weeks ahead, as the body deteriorates.
Now, millions of years hence, looking at fossilized remains... Might one expect diotomacious fossilization processes to affect tsunami victims, SPECIFICALLY? Yes, so there you go.