On July 10, the Yellowstone National Park Administration posted a short, optimistic message on its website as follows:
The highly popular area near Jenny Lake in the Grand Teton National Park in Wyoming is closed to the public for the near future due to concerns about cracks in the surrounding rock massif.
Last week in the rock mass above the observation area of the Hidden Falls, the park's rangers discovered recently appeared cracks, which are rapidly widening. As a consequence, in the interest of the safety of visitors, the National Park Service has implemented an emergency closure of both the Hidden Falls area and the Falls area in the western part of Jenny Lake.
Exum Mountain guides are relocating their services so that park visitors can now go boating on the West Bank, cascading canyon or around the lake, and enjoy some areas of the West Coast, as well as open areas of the Jenny Lake complex. …
Yellowstone today is such a place that when something is closed there, the conspiracy theorists are in panic, because if access is closed somewhere, then the authorities are hiding something. Naturally, on this occasion, MrMBB333 and Mary Greeley videos were immediately released.
From the video, judging by the comments, no one understood anything, since the authors of the video in this case themselves are not very much in the subject. Therefore, we will explain.
Promotional video:
First, let's see what this Jenny Lake is:
As you can see, the lake is small and the main lake of the park, Yellowstone Lake next to it looks like the sea:
Yellowstone Lake with easily recognizable contours is located in the upper left corner of the picture, and the place where the Jenny Lake is located, on the rocks around which the rock began to fall apart, is marked in red.
Now let's see the boundaries of the Yellowstone supervolcano caldera:
As can be seen from the figure, if you draw a line from the center of the caldera towards Lake Jenny, the direction will be southeast.
The earthquake swarms observed and observed in Yellowstone tend to move in the same direction, that is, to the southeast: the gray circles show the swarm of summer 2017, red - the swarm of winter 2018.
Observing this trend, we, earlier, made the assumption that the reason for the swarm displacement is the movement of the mantle plume that forms Yellowstone, which emerges from under the caldera and moves to the southeast (moreover, this trend of displacement of mantle plumes is characteristic of the entire Western Hemisphere).
To test this hypothesis, we would need a couple of smart guys from the US Geological Survey, who know how to handle gravimeters, that is, devices that register micro-gradients of gravity. Since the gravity above the top of the mantle plume is slightly higher than in the neighboring regions, based on the change in its level upwards, one could say for sure: yes, the mantle plume moved towards Lake Jenny, that is, somewhere to the southeast.
Probably there are such guys in the USGS and they have been running around the caldera with their tongues hung out with sensors for a long time. Unfortunately, they do not provide us with the obtained data. And unfortunately, we don't need their data now, because the rocks to the southeast of the caldera are beginning to crack at the seams. The only reason for this can only be the approach of magma. That is, the hottest zone of the Yellowstone mantle plume is already somewhere there, forcing the rocks to begin to rise and bulge.
We do not know how and when it will end, but if the mountains that have stood indestructible since the Delaware times suddenly begin to crack, then a volcano begins to form under them. The time of its formation determines only the speed of movement of the plume and the state of the magma chamber under the caldera, which this plume heats up. If the roof of the magma chamber in this place is fragile, then the eruption in this place can begin within months.