演講資訊

摘要：

Planetary Geologic Mapping and the Concept of Planetary Chronostratigraphy

The evolution of planetary surfaces is recorded in their geologic record in which every significant event is stored in its own rock and mineral characteristics. Depending on the nature of events and subsequent modifications this record can become considerably complex and in order to unravel events we require information about their timing.

While in-situ sampling and laboratory measurements are certainly the most exact ways to determine rock compositions and rock ages, it is also inefficient and not necessarily representative, as the Apollo program has shown.

Remote-sensing imaging has been an indispensable tool to help mastering this challenge as largely undisturbed planetary surfaces have been accumulating a record of impact craters since solidification of the surface. These impact craters – in frequency and size – are used as chronometers to establish a chronological framework. While our knowledge about planetary surface ages and events is based on this methodological concept, it has also been challenged with respect to its validity due to the advent of planetary migration models.

This talk will focus on the methodological ideas and concepts, addresses a number of challenges connected to this method and presents a number of recent research findings, focusing on Mars and Ceres.

Further Reading:

AP Rossi & S van Gasselt (2018): Planetary Geology.- LXV+433 pp. Cham (Springer).
S van Gasselt & G Neukum (2015): Chronostratigraphy.- In: M Gargaud, WM Irvine (eds.) Encyclopedia of Astrobiology, pp. 454-466, Heidelberg (Springer).