This book presents essential data on the geology of the Puchezh-Katunki crater – an early Jurassic crater located on the East European Platform, with an impact structure that is ca. 80 km in diameter. Offering a comprehensive guide, it reviews the studies carried out during the last several decades on this prominent but not well-known impact structure. It offers the international community state-of-the-art information on the crater with regard to e.g. structural mapping, drilling (including the Vorotilovo well, which is 5374 m deep), geophysical research, and the petrological analysis of impactites and various breccias. In addition, the book includes new results from the mineralization and crystallizations beneath this large impact crater, and suggests new models for crater formations.
Despite their global importance, little is known about the few existing examples of impacts into marine environments and icy targets. They are among the least understood and studied parts of impact crater geology. The icy impacts are also of great importance in understanding the developments of the outer planets and their satellites such as Mars or Europa. Furthermore, the impact mechanisms, crater formation and collapse, melt production and the ejecta distribution are scarcely known for impact on targets other than the "classical" solid silicates of the continental crust. The reaction of water and ice to impacts clearly deserves a more thorough study. The understanding of impact effects and consequences in the case of aqueous hits, soft sediments and icy targets has not been thoroughly explored and comprises the main focus of this book. A number of papers in the field of hypervelocity impacts on ice are included. These cover a review of available literature in the field of laboratory studies of such impacts, large impact structures on Titan, predicting impact cratering on a comet nucleus, and a novel report on the survival of bacteria fired at hypervelocity into icy surfaces. This latter paper is concerned with astrobiology and in particular Panspermia (natural migration of life through space).
An asteroid or comet will inevitably strike the Earth some day, and potentially cause great destruction. This volume considers hazards due to collisions with cosmic objects, particularly in light of recent investigations of impacts by the authors. Each chapter, written by an expert, contains an overview of an aspect and new findings in the field. Coverage describes and numerically estimates the main hazardous effects.
This book presents a comprehensive overview of Australian impact structures and related mineralization, including a discussion of the significance of many of these structures for crustal evolution. The book focuses in particular on Archaean impact ejecta/fallout units in the Pilbara Craton of Western Australia, large exposed and buried impact structures, and on the geophysical evidence for possible to probable impact structures. Thanks to their long-term geological stability, Precambrian and younger terrains in the Australian continent contain 38 confirmed impact structures and 43 ring and dome structures, many of which constitute possible to probable asteroid impact structures. The impact structures have been the subject of more than half a century of studies and range from several tens of meter-large craters to buried structures larger than 100 km in diameter. Discoveries of impact fallout units in the Pilbara Craton have defined the Pilbara as one of the two best documented terrains where Archaean impact ejecta/fallout deposits are identified, the other terrain being the Kaapvaal Craton in southern Africa. A synthesis of evidence from both cratons indicates periods of large asteroid bombardments during ~3.47 – 2.48 billion years-ago, including peak bombardment about 3.25—3.22 billion years-ago. The latter period coincides with an abrupt transformation of an early Archaean granite-greenstone crust to mid to late Archaean semi-continental crustal regimes, underpinning the significance of heavy asteroid impact events for crustal evolution. Apart from proven impact structures, Australian terrains display a range of circular features, including morphological and drainage rings, circular lakes, volcanic craters, tectonic domes, oval granite bodies, mafic igneous plugs, salt diapirs, and magnetic, gravity and seismic anomalies, many of which are of a likely impact origin. Thermal and hydrothermal processes associated with impact cratering bear important consequences for the formation of mineral deposits, such as Ni at Sudbury, Pb-Zn at Siljan and Kentland. Impact structures may also provide sites for the accumulation of hydrocarbons, whereas in some instances fracturing associated with impact structures allows outward migration of oil and gas.
The present volume is the result of activities within the scientific programme "Response of the Earth System to Impact Processes" (IMP ACT) of the European Science Foundation (ESF). The ESF is an association of 67 national member organisations devoted to scientific research in 24 European countries. The IMPACT programme is aimed at understanding meteorite impact processes and their effects on the Earth System. Launched in 1998 for a duration of 5 years, the programme is now supported by 15 ESF membership countries. The programme of meteorite impact research and operates through deals with all aspects workshops, exchange programs, and short courses. The 4th IMPACT programme workshop "Meteorite Impacts in Precambrian Shields" took place on May 24-28, 2000, in Lappajarvi, western Finland. A total of 84 scientists from 19 countries from Europe, North America, and Africa participated in the workshop. During the workshop, 43 oral, 31 poster, and several video presentations were made. An exhibition of impactite rocks from Finnish craters and two excursions were organised. The excursion to impact melt rock outcrops of the Lappajarvi structure took place during the workshop. The Karikkoselka and Saaksjarvi impact structures in south-central Finland were visited during the post-meeting excursion.
Comprises 28 papers which grew out of the International Conference on Large Meteorite Impacts and Planetary Evolution, August/September, 1992 in Sudbury, Ontario. The interdisciplinary papers, encompassing diverse studies from trace element geochemistry to planetary exploration, are arranged into f
Hydrothermal processes on Earth have played an important role in the evolution of our planet. These processes link the lithosphere, hydrosphere and biosphere in continuously evolving dynamic systems. Terrestrial hydrothermal processes have been active since water condensed to form the hydrosphere, most probably from about 4.4 Ga. The circulation of hot aqueous solution (hydrothermal systems) at, and below, the Earth’s surface is ultimately driven by magmatic heat. This book presents an in-depth review of hydrothermal proceses and systems that form beneath the oceans and in intracontinental rifts, continental margins and magmatic arcs. The interaction of hydrothermal fluids with rockwalls, the hydrophere and the biophere, together with changes in their composition through time and space, contribute to the formation of a wide range of mineral deposit types and associated wallrock alteration. On Earth, sites of hydrothermal activity support varied ecosystems based on a range of chemotrophic microorganisms both at surface and in the subsurface. This book also provides an overview of hydrothermal systems associated with meteorite impacts and explores the possibility that hydrothermal processes operate on other terrestrial planets, such as Mars, or satellites of the outer planets such as Titan and Europa. Possible analogues of extraterrestrial putative hydrothermal processes pose the intriguing question of whether primitive life, as we know it, may exist or existed in these planetary bodies. Audience: This volume will be of interest to scientists and researchers in geosciences and life sciences departments, as well as to professionals and scientists involved in mining and mineral exploration.
A collection of international contributions presenting current knowledge of impact tectonics, geological and geophysical investigations of terrestrial impact structures, and suggested new impact structures, resulting from the IMPACT program.
Interpretations of the geological processes operating on Mars are based on our knowledge of processes occurring on Earth. This 2007 book presents contributions from leading planetary geologists to demonstrate the parallels and differences between these two planets, and will therefore be a key reference for students and researchers of planetary science.
