August 23, 2013
Floor-Elevated Craters
image by Howard Eskildsen, Ocala, Florida
Here are measurements of the depths and diameters of Guericke B, Tolansky as well as the non-modified craters Kundt and Darney. The latter two are in the same general area and have not had their floors elevated as the first two have. By estimating the first two craters original depths and comparing them with the current depths it can be calculated that Tolansky's floor may be 1.5 km higher than its original depth, while Guericke B's could be about 1.9 km higher than it once was. I like to think of them as floor-elevated craters. I can only think of three things that could elevate the floor to that degree: floor uplift by volcanic intrusion, floor elevation by volcanic extrusion ( or a combination of the two), and fill by fluidized ejecta. I do not believe that the latter was primarily involved here. Based on high sun illumination it is apparent that the interior of Tolansky is dark like mare basalt, while Guericke B's interior is brighter than surrounding basalt. This leads me to believe that Tolansky's elevated floor is due to extrusion (though some floor uplift may be buried beneath the basalt), while Guericke B's floor elevation is due to intrusion of magma beneath the floor with uplift and fracturing of the original floor.
Howard Eskildsen
Related Links
21st Century Atlas charts 22 & 23.
