August 21-22 – Paramushir, Days Five & Six, Now that’s what I call a pit!
August 21-22 – Paramushir, Days Five & Six, Now that’s what I call a pit!
Sep 3 2006, 08:39 AM
Group: TREC Team
Joined: 18-April 06
Member No.: 31
NOTE: The eight days of journal entries from August 17-24 were written while I was camping ashore at Pernatoye Lake, along Vasil’ev Bay on southern Paramushir Island. I am typing them in mostly verbatim from my handwritten journal from the field – with just minor editing/additions for content and clarity – now that I am back on the Gipanis.
Tuesday, 22 August
I’ve been fairly busy since my last entry, which is good. On Sunday, after I had finished helping Tolya and Pat with the water/mud interface sampling, the geology group returned around 8 pm. They were very muddy from working on the peat excavation and not even close to being finished. They would need to go back at least one more day.
Yesterday, Monday, I went with the geology group to see the peat pit and do some excavations of my own – archaeology or geology, depending on what I found. The peat pit was about 2.5 meters deep by 1 meter wide by 3-4 m long. The first thing that had to be done was for Jesse to use a bucket on a rope to bail out the hole. While he did that, Jody showed me the two small test pits that she dug the day before. About 70 cm below the surface in each of the excavations was the Kuril Lake tephra, created by a Crater Lake/Mount Mazama-sized eruption in south Kamchatka about 7500-8000 years ago. It is about 20 cm thick in north Paramushir and about 10 cm thick on southern Paramushir – very fine grained and yellowish brown. It is so distinctive that it can easily be used to tell the age of a sediment layer in an excavation.
While Jody, Katya, Tanya and Jesse got busy describing and sampling the peat for radiocarbon dating, diatoms/pollen identification and tephra. This was a tedious task since there were many tephras and they were sampling every few centimeters over a 3 meter depth. In the peat pit, the Kuril Lake tephra was 240 cm below the surface.
I carefully looked for a good place to dig an archaeological or geological test it. I didn’t find any good archaeology sites (pit houses, etc) that were in the immediate vicinity (within the bear-safe radius distance) so I ended up digging a deep, narrow geology hole. The weather was very nice this day – clear and sunny all morning – and while I was digging there was just enough breeze to keep MOST of the flies away. I dug down about 90 cm (as deep as I could reach with both arms and shoulders in the hole) and found the Kuril Lake tephra plus the finer black tephra below it. I carefully described the stratigraphy in my hole and headed back over to the others. (See picture below)
My first completely solo excavation! I single-handedly dug the entire excavation, described it and drew up the section. I have become an accomplished novice geologist! Near the bottom of the pit, which is about 90 cm deep, you can see the distinctive Kuril Lake tephra – lighter brown in color and thick, with a black tephra layer just below it.
It was nearing midday and time to start a fire to boil water for tea. Since everyone else was occupied with “peat tasks,” I took on the task of starting the fire with the semi-dead branches of shrubby Scotch pine, called kadratch, that Jesse had collected. I managed to start the fire with only a small bit of difficulty (and several timely and helpful suggestions from Jesse). Then I collected water from one the boggy lakes nearby and set it to boil. About an hour after I had started (about 2:30-ish), we had boiling water, had made tea and set out our lunch – canned fish much like sardines, called sprota, fish liver spread, canned white beans, corn, bread, canned stuffed peppers and hot tea, with waffley (sugar wafer) cookies and candies for dessert. It was a very pleasant repast.
After lunch, I showed Jody my first excavation and she showed me another place nearby where a spring came out of the hillside where I could easily dig another. The spring had eroded down the hillside about a meter, so all I had to do was to cut the turf off of the top and clean the surface all the way down. I was quickly able to expose about 1.2 m down to the surface of the muddy and mushy area below it. Since the upper section was already weeping with spring water, I first carefully described the upper section of about 50 cm of peat that was punctuated by several sandy tephras, then the finer, silty dark and light alternating layers that were most likely lake sediments, with a few more tephras, before digging any further. The lake sediments included a thick, gray sandy tephra layer (about 5 cm thick) that I had also seen my first excavation. After that, I quickly dug down further into the squishy, squelchy mud at the bottom of the excavation – while also trying to create mini-canals to drain away the quickly collecting water that was seeping through the upper sections. I was able to briefly, before the watery mud filled it back in, expose, measure and describe the rest of the lake sediments down to the Kuril lake tephra. [My “Rite in the Rain” notebook became a “Rite in the Mud” notebook.] In this excavation, the Kuril Lake tephra was very bright yellow, like sulfur – perhaps falling in a lake changed it somehow.
Lake sediments can be identified by their very fine particles – mud, silt and clay – and they often have a cyclic light/dark appearance due to seasonal differences in deposition rates and materials, especially if the lake is frozen over in winter. Lake deposits do not “grow” very quickly in most places when compared to soils and peat, for two main reasons – the particles are very small and there is not very many of them accumulating (except in locations with lots of sediment transport, such as glacial lakes). Peat on the other hand, grows very fast – as fast as plants can “drown,” not rot and have other plants grow on top of them. Peat grows significantly faster than soil or lake sediments. This means that you need to dig much deeper to find the same aged tephra layers, but also that there is much more separation in between tephra layers making them easier to identify.
The second excavation that I had dug told a story of what had happened in this location over the past 7000 years. The lake sediments underneath the peat tells us that the area – which was currently covered with small lake remnants, boggy springs and peat – used to be a larger lake sometime in the past, possibly before, but definitely after the Kuril Lake eruption. Eventually, the lake level dropped. This could be due to lake sediments filing it in, tectonic lifting in the landscape, or just a climate change that affected how much water collected (for example, it got drier). In one of these or another way, the lake level dropped below the elevation of my second excavation and marshy, boggy plants started growing along the margins. These died and more grew on top, creating the peat. Today, there are grasses and other shrubs, etc, living on top of the peat layer meaning that in that specific location, the peat grew until it was above the water level (essentially it grew itself out of its own ecosystem) or the area has better drainage, so plants that like drier soil could grow there.
After I finished describing my second excavation, I returned to the peat excavation to find that madness had broken out. While digging the pit deeper, they had hit an artesian well. These are places where the water is under pressure and flows underground, rather than just seeping through permeable layers. They were working in salvage mode to recover as much as possible of the information below the water level of the rapidly-filling pit. Katya was quickly trying to bail out water with Jesse and also to use the shovels to taken intact sections of peat from the wall of the pit up to the surface. Then the pieces of the wall, called monoliths, were laid back together and measured, described and sampled in reverse order – from the bottom, about 3.5 m below the surface. It was quite hectic trying to bail water and mud out, pull out wall samples and reconstruct them, document the descriptions in reverse order and take samples and label them. Quickly all 5 of us became involved with the endeavor. By 7 pm, we had gotten to a very distinctive tephra layer (so Tanya would know where to begin today), had packed up all of the bags and equipment and started back toward the camp. (See pictures below)
On the left: Katya Kravchunovskaya looks down into the 3 meter deep peat excavation as Jody Bourgeois and Tanya Pinegina work to describe and sample the exposed surfaces on the walls.
On the right: Jody Bourgeois hugs a dirty Katya Kravchunovskaya. After the hitting the artesian well, Katya worked hard in the bottom of the pit to keep up with removing the incoming water and mud as well as to salvage remaining samples of the wall (one of which you can just see in the bottom left part of the picture).
It was to be a special evening as we were expecting guests! On this end of Paramushir, there is a lighthouse and the lighthouse keeper, Sasha, and his wife, Genya, were joining us for supper. We had met them yesterday and they are generously going to help transport our gear and equipment to the beach when we are picked up later this week. As the 5 of us walked back, we were greeted by Sasha and Chara (the capaka – dog – who chased the bears away and belongs to Sasha and Genya) in Sasha’s large Russian truck. He graciously drove us the remaining approximately 2 km back to the house, over the very bumpy road, with Chara racing along behind us.
We enjoyed a lovely meal complete with ekra (red caviar), fresh bruzhnika (salmon berries), canned marinated wild mushrooms that Genya provided to go with our chicken and potatoes. Even though neither of them speaks any English, they were happy with all our company for the evening. Typically, they only see other people twice a year, when supplies are delivered to them by boat – otherwise it is just the two of them. So they were very happy to help us and socialize with other Russian-speakers for the evening.
Today, Jesse, Jody, Tanya and Katya are heading back to the peat pit to finish the describing and sampling. Pat, Tolya, Sasha and Pasha are working on drying, organizing and packing their gear to go back to Gipanis and eventually to Magadan. After I finish writing this, I will draw up my sections from yesterday and then hang around the house for the rest of the day.
Tuesday, 22 August 26
It started raining between 11 and noon. Rained steady for about an hour or more, then drizzled until mid afternoon. I finished drawing my section and then read/napped in my cot and sleeping bag until about 2 pm. Then I did some yoga to warm up while waiting for the geology group to return.
Jody, Tanya, Katya and Jesse returned around 3 pm – finished with the peat pit, but wet and hungry. We celebrated their successful completion with some tea, dried apple rings, almonds and chocolate around the campfire. It has since stopped raining and tomorrow and the next day the weather is supposed to be better. At some point, we will move our gear to the lighthouse in preparation for being picked up late in the afternoon on the 24th.
|NSF Acknowledgment & Disclaimer||Time is now: 24th February 2017 - 10:01 PM|