Tuesday, September 2, 1997 TERRESTRIAL IMPACT STRUCTURES I 8: 30 a.m.–12: 00 noon Chairs: T. E. Bunch and R. A. F. Grieve Pesonen L. J.* Elo S. Puranen R. Jokinen T. Lehtinen M. Kivekäs L. Suppala I. The Karikkoselkä Impact Structure, Central Finland: New Geophysical and Petrographic Results Abate B.* Koeberl C. Underwood J. R. Jr. Fisk E. P. Giegengack R. F. BP and Oasis Impact Structures, Libya, and Their Relation to Libyan Desert Glass: Petrography, Geochemistry, and Geochronology Kriens B. J.* Herkenhoff K. E. Shoemaker E. M. Structure and Kinematics of a Complex Crater, Upheaval Dome, Southeast Utah Skála R.* Jakeš P. Shock-induced Effects in Natural Calcite-Rich Targets as Revealed by X-Ray Diffraction Ormo J.* Lindstrom M. Sturkell E. Tornberg R. The Middle Ordovician Lockne Crater as a Small-scale Model for Impacts at Sea Ahulu S. T.* Overview of Bosumtwi Crater, Ghana Hildebrand A. R. Pilkington M.* Grieve R. A. F. Stewart R. R. Mazur M. J. Hladiuk D. W. Sinnott D. The Steen River Impact Structure, Alberta, Canada Sharpton V. L.* Dressler B. O. Shock Attenuation and Breccia Formation at a Complex Impact Structure: Slate Islands, Northern Lake Superior, Canada Andreoli M. A. G.* Hart R. J. Ashwal L. D. Tredoux M. Ni- and PGE-enriched Quartz Norite in the Latest Jurassic Morokweng Impact Structure, South Africa Koeberl C.* Reimold W. U. Armstrong R. A. The Jurassic-Cretaceous Boundary Impact Event: The Morokweng Impact Structure, South Africa Boivin L.* Summary of Work in the Manicouagan Impact Structure Hölker Th.* Deutsch A. Masaitis V. L. Geochemical Characteristics of Impactites from the Popigai Impact Structure (Russia) Masaitis V. L.* Naumov M. V. Mashchak M. S. Three-dimensional Modeling of Impactite Bodies of Popigai Impact Crater, Russia Valter A. A.* Mineralogical, Geochemical, and Geological Data for the Interpretation of the Crater Base Structure of the Complex Terny Astrobleme (Krivoy Rog, Ukraine) _____________________ *Denotes speaker.