This volume is the latest of eight books as a result of the activities of the scientific program on ¿The Response of the Earth System to Impact Processes¿ (IMPACT) of the European Science Foundation (ESF). The ESF is the European association of national funding organisations of fundamental research, with more than 60 member organisations from more than 20 countries. One of the main goals of ESF is to bring European scientists together to work on topics of common interest. The ESF IMPACT program deals with all aspect of impact research, mainly through the organisation of workshops, exchange program, short course, and related activities. An important aspect of the program is to stimulate interdisciplinary and international research. Impacts of asteroids or comets on the earth surface have played an important role in the evolution of the planet. The ESF IMPACT program is an interdisciplinary program aimed at understanding impact processes and their effect on the earth system, including environmental, biological, and geological changes, and consequences for the biodiversity of ecosystems. The key goal of the program, to comprehend the processes that are responsible for these interactions, has been met with by eight workshops and published proceedings from these. The workshop from which this volume resulted, was devoted to impact tectonic studies. It was located in the small town of Mora in the western part of the ring basin of the very large Siljan impact structure in Sweden.