Solid Earth www.solid-earth.net 1869-9510 1869-9529 1 1 2010 10.5194/se-1-71-2010 http://www.solid-earth.net/1/71/2010/ http://www.solid-earth.net/1/71/2010/se-1-71-2010.html http://www.solid-earth.net/1/71/2010/se-1-71-2010.pdf 71 83 2010-07-21 Candidates for multiple impact craters?: Popigai and Chicxulub as seen by the global high resolution gravitational field model EGM2008 J. Klokočník jklokocn@asu.cas.cz J. Kostelecký I. Pešek P. Novák C. A. Wagner J. Sebera Astronomical Institute, Academy of Sciences of the Czech Republic, Ondřejov, Czech Republic Research Institute for Geodesy, Topography and Cartography, Zdiby, Czech Republic Department of Advanced Geodesy, Czech Technical University, Prague, Czech Republic Department of Math., Faculty of Applied Sciences, University of West Bohemia, Pilsen, Czech Republic Laboratory for Satellite Altimetry, NOAA, Silver Spring, MD, USA In 2008 the new Earth Gravitational Model (EGM2008) was released. It contains a complete set of spherical harmonic coefficients of the Earth's gravitational potential (Stokes parameters) to degree 2190 and order 2159 and selected orders to degree 2190, that can be used for evaluation of various potential quantities with both the unprecedented accuracy and high spatial resolution. Two such quantities, the gravity anomaly and second-order radial derivative of the disturbing potential, were computed over selected areas with known impact craters. The displays of these derivatives for two such sites clearly show not only the strong circular-like features known to be associated with them but also other symmetrical structures which appear to make them multiple impact sites. At Popigai, Siberia, the series of circular features fall in a line from the "primary crater" in the southeast (SE) direction. 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