Japan 2023. Day 9. Kiritappu

The weather has turned, and not for the better. Last night we had steady rain, although the morning started sunny enough. Today the plan was to head south from the Sea of Okhotsk to the Pacific Ocean. Our center of operations was to be the town of Hamanaka, although the plan for the morning was to spend time walking the sea cliff of Kiritappu. The shore here is very interesting; on one hand it resembles very much the central California coast, with its spectacular sea cliffs, but instead of having a step-like series of uplifted wave-cut terraces the land forms an extensive table land that extends deeply into the land. I spent some time looking at the stratigraphy exposed in the cliffs, and was surprised to see a thinly laminated unit (a coastal lagoon deposit?) overlain by a very coarse conglomerate with well-rounded pebbles (a fluvial deposit?) that would suggest a regression. But how to explain the tableland? Perhaps the regression was followed by a transgression that blanketed the sequence with a shallow marine deposit. And then we had a drop in sea level (the Ice Age) that allowed the streams to cut deeply into the coastal plain. The last glaciation came to an end, an estuary was formed, and eventually sedimentation turned it into a wetland (same old story I have told you before), but at some point this part of the island was uplifted, perhaps in response to subduction to the east, because the tableland was exposed forming "mesas" along the shoreline, with a few gaps through them, not unlike to the "mesas and gaps" geomorphology of Southern California. Keep this image in mind because it will become significant in later paragraphs.

So there we were on top of a 60 m sea cliff, peering down into the water and its dancing stands of kelp (or kombu as the Japanese would call it). Then Hellen detected a small head bobbing in the water, which on closer inspection turned out to be a sea otter clutching something in her arms. We followed her progress in fascination as she swam parallel to the coast for a good couple of kilometers, after which she seemed to let go of the log (?) she was carrying. On closer inspection we determined her to be a mother otter, apparently taking her cub for a swim. The kid was a lump, and whenever she let go of him he would float like a log doing absolutely nothing. In the meantime she took the opportunity to groom herself, spin over and over again while she joyfully enjoyed the freedom of not carrying the kid, did number two leaving behind a big cloud of brown, and from time to time checking on her baby with lots of sniffing and kisses. She would carry him for a few minutes, and then let him adrift again, to make his best impersonation of a bit of flotsam. I confess to some bias here, because I keep referring to the parent as Mom, but there are folks that claim that with sea otters it is the dad who does the babysitting and training of the kid. My only excuse is that I was observing this from far above, and regardless of gender all sea otters have whiskers.

For lunch we went to the Kiritappu Wetland Center, where we had a seafood curry that was really good, as well as some ice cream made with the best Hokkaido milk. I finished earlier, so I went down to the lobby, where they had a great soil profile of the wetlands. I am not sure how they make these, but it looks as if they cut a trench into the soil profile, soak it with transparent acrylic glue and press against a board, let it dry, and then peel a faithful copy of the soil for inspection. This is the third I have seen within the last week, and I had no problem recognizing the top tephra layer of a nearby eruption 300 years ago, but below it there was the strangest sequence of thin peat layers interspersed with wedges of marine sand up to 20 cm thick, repeating at least five times. What the heck was this? Quick incursions of the sea into the wetland? Hmm ... OMG, these are tsunami deposits, formed as different tsunamis entered the gaps in between the mesas caused by uplift, which had blanketed with sand all of the lowlands. How neat is that?

We were going to spend the afternoon canoeing through the channels of the wetlands, but the wind was too strong and the local outfitter chose instead to invite us to his ranch, Land's Edge, to look at his horses, learn some homesteading abilities (like chopping wood), take a walk through the coastal forest, and finally come to the edge of the land, where he has built a wooden platform for no apparent purpose. The view was magnificent, and I jokingly said that what he needed to do was to build a small room to hold tea ceremonies. No sooner had I uttered these words that he and his assistants took off their backpacks, pulled out thermos and boxes of cookies, and treated us to a tea ceremony of their own. Fun!

Tonight was our last communal dinner, and we chose a sushi restaurant to celebrate. The meal was magnificent, and I suspect it is going to be hard to beat once I am on my own.