During
the 8 days of stay at lake Cheko the following tasks were performed:
Study of the trees that survived the
explosion, found presently on the
lakeshores: they should preserve an important record on the impact
dynamics.
The bottom of the lake has beem filmed in
several locations, and it
happens that all the deep part is covered by a carpet of branches. This is compatible with the hypothesis that a forest was there before the
Tunguska event.
Dense-spaced magnetometric survey of the
lake
bottom, that would allow us to estimate size and nature of the
hypothetical buried object detected by our seismic reflection data
below the lake bottom. To avoid as much as possible
interferences by metal objects, the magnetometry has been done
with an inflatable rubber boat and plastic/wooden oars. The
GPS
and the notebook necessary to record the position and the
magnetic readings where always kept in the same position. The
suface of the lake has been entirely covered, going forward and back in
many North/South (almost) stright lines, transversally separated by 10
m. The magnetometry data are currently under study.
Collection of rock samples from the region surrounding
the lake. The study of these rocks will help in interpreting the
mineralogy of the lake’s deposits.
Research
on an old creek bed that was possibly cut off or
rerouted after the 1908 event. Difficulties in researching the creek
bed arise due to the fact that 20 centimeters under the surface there
is permafrost that cannot be dug up.
