Call for papers
Circular-shaped features on surface of planetary bodies. Recognition of impact cratering as a major process on the Earth's evolution
Humankind in front of the mirror. A perspective of our own planet thanks to space missions.
- Nombre: Marius Ramirez-Cardona
- Country: Mexico
- E-mail: mariusramirez1975@hotmail.com; mariusr@uaeh.reduaeh.mx
- University: Universidad Autonoma del Estado de Hidalgo - Universidad Nacional Autonoma de Mexico
Abstract: In the last two decades, post-Apollo's missions have apported valuous and concise information about surface features of planets and satellites. The majority of recognizabled structures locallized on the surfaces are circular frameworks (including ovoids, coronae and arachnoids). So, the concept of a chaotic distribution of single and complex ring and circular-shaped structures is still now the more appropiate and conspicuous description of any planetary body surface. These rings are mostly the evidence of meteor impacting, that is accepted as the main process of space weathering on the surfaces of airless planetary bodies.
Gravity fluctuations and orbital radar data were used by NASA's Clementine and Lunar Prospector (Moon) and Messenger (Mercury) satellites to give information on the target surface of the Moon. Remote sensing data evaluation was also proved as a good methodology to delimit hidden or subsurface structures.
Despite of the atmosphere effect burning up smaller meteors (e.g., Venus and Earth cases), presently, more than 160 impacts structures have been identified on Earth. Exploration techniques focused earlier on extraterrestrial planetary bodies have been applied latter to Earth's surface. For example, JERS-1 or Landsat-7 satellite images and gravitation fluctuations measures (e.g., GRACE satellites) have been combined to inspect and detect circular structures associated to probable impacts.
This conference seeks to show the meteor cratering influence on the geological and biological evolution of our planet. In order to illustrate that idea, four impact craters have been chosen as paradigmatic cases taking into account archetypical feature, diameter size, changes on target material, biological evolution influence and prominent scientific trends:
-The Barringer meteorite crater (Arizona, USA) is a gigantic hole in the middle of the arid Arizona desert. It symbolizes the archetypical circular structure.
-The Chicxulub (Yucatan, Mexico) crater is associated to dinosaurs extinction 65 millions of years ago. This theory have been the subject of a controversy derived from the age estimation of the impact.
-The Kebira crater in western Egypt, at the Lybian border, is the largest crater in Sahara desert. (03/03/2006).
-The Wilkes Land evidences of impact crater lying hidden more than a mile beneath the East Antartic ice sheet. It is probably the cause of the Permian-Triassic (250 million years ago) mass extinction (06/06/2006).
