Abstract:
A study was carried out for two early Paleozoic impact structures
in Sweden. These two impact structures (Granby and Tvaren) are located in the
southern part of Sweden. Common features can be identified of these two structures
as similar diameter of ca 2 km and a substantial post impact fill with Paleozoic
sedimentary rocks. The Granby structure represents an almost completely preserved
impact crater within a Paleozoic sedimentary rock sequence — only the uppermost
part of the raised crater rim might be eroded and was subsequently covered
by Quaternary sediments. The Tvaren structure is eroded below the surrounding
pre-impact Paleozoic cover rocks into the underlying crystalline basement and
has a Quaternary sediment fill. Gravity measurements were carried out on land
and sea ice. The inverse gravity modeling shows a gradual change of density and
the equivalent porosity with radial distance from the explosion center within the
damage zone around and below simple craters.
Citation:
Henkel, H., Ekneligoda, T.C. (2010). Modeling simple craters using gravity measurements. In N. P. Ratnayake, A.M.K.B. Abeysinghe, H.M.R. Premasiri & S. Karunaratne (Eds.), Proceedings of the 5th Annual Conference on Earth Resources for National Development (pp. 37-40). Department of Earth Resources Engineering, University of Moratuwa.