KEENE VALLEY - Standing before about two dozen earth science teachers Monday, glacial geologist Andrew Kozlowski pointed out some trees that were all noticeably leaning in one direction and one that had split vertically at the bottom from the movement of the ground below it.
The trees are on the edge of the 82-acre landslide on Adrian's Acres in Keene Valley. The slow-moving slide began in May 2011 after an extremely wet spring.
"Most of the movement of these trees wasn't happening last July," Kozlowski said. "The forces are finally catching up and distributing themselves."
Glacial geologist Andrew Kozlowski shows a group of earth science teachers a tree that has split after the ground underneath it moved during a slow-moving landslide at Adrian’s Acres in Keene Valley.
(Enterprise photo — Mike Lynch)
Kozlowski, who works for the New York State Museum, has been studying the landslide since May 10, 2011. On Monday, he was giving a tour to the teachers as part of as part of a lesson on geologic hazards and glacial deposits in the state. The lesson was part of the three-day D.H. Cadwell Earth Science Workshop, conducted by Kozlowski and other museum scientists.
The first day consisted of a trip to the Keene Valley landslide. Today the teachers are scheduled to visit mines in the eastern Adirondacks, and Wednesday the group plans to look at sedimentary rocks from Keene Valley to Lake Champlain.
The goal of the annual workshop is to provide the teachers with field experience that they can bring back to their classrooms and use when teaching their students.
At the Keene Valley landslide, the teachers were provided with data that Kozlowski and other scientists had gathered at the site. They also visited monitoring stations that track the landslide's movement and the ground's water levels.
"A lot of the geological phenomena that we talk about in our classrooms are ancient processes that occur very, very slowly over a time span that is not really perceptible to human beings," Kozlowski said. "(Here), geology is happening right before our eyes."
The physical changes to the landscape are obvious. At the crown of the landslide, the earth has sunk, leaving a dirt cliff that is at least 25 feet high in some places. Lower down on the hill, the ground has shifted horizontally, causing trees to grow at diagonal angles.
In the first days of the landslide, it moved as much as 2 feet in one day near the top. Now it moves about 2 to 3 inches per month near the bottom of the slide, which is called the toe.
"It's not moving, that we would perceive as humans, at a really fast pace, but in terms of geological processes, the landslide is still very active," Kozlowski said.
One can stand on parts of the landslide toward the middle and not even realize any movement has taken place.
"Toward the center of the slide's land mass, all the trees are completely vertical," Kozlowski said. "There's no indication at all that you are on a landslide. They are simply along for the ride. You only see the displacement and movement around the periphery of the slide where the displacement is taking place."
Steven Houston, a freshman earth science teacher in Baldwinsville, said he didn't even know about the landslide until seeing it Monday. But he said he's taking lots of photographs and notes, and plans to share the information through classroom exercises.
"That's something I can take back to the classroom: real-life practical examples that I can share with the kids," he said. "They can see how it affects people's lives, as you can see today. This landslide is affecting people's homes in a negative way, reducing their home values and in some cases they have to move out."
Kozlowski said six homes have been affected by the landslide. The teachers visited several of the homes, including one site where the house was removed, another where it was a few feet from a roughly 20-foot cliff and a third where the owners had moved it roughly 400 feet.
The last home is owned by Jim and Charity Marlatt. The full-time residents bought property from their neighbor and spent months consulting with geologists to determine if the site would be safe in the long term, even though it's still a couple of hundred feet from the top of the landslide.
"(It was) a grueling process emotionally," Charity Marlatt said. "We feel as though we made the most educated decision that we possibly could."
The landslide is not something they ever imagined happening when they moved into the home, she said. In the Adirondacks, most people think of the fast-moving landslides that occur on steep slopes in the backcountry, not ones that move at a snail's pace in a residential area.
"They are very different beasts," Kozslowski said. "One is a slow-moving juggernat mass, and the others are these rapid, intense debris pulls coming down the mountains. They are totally different. They have totally different mechanics and behavior responses. But they both illustrate that natural hazards, geological hazards such as landslides, are clearly present here in the Adirondacks."