Growth rhythms as an indicator of the Earths rotation and climate changes in the geological past

01.01.2007 - 31.12.2010
Grant agency: 
Registration number: 
Internal investigator/coinvestigator: 
Interní řešitel: 
is principal investigator
Internal collaborators: 
Petr A. Čejchan
Internal collaborators: 
Jiří Filip
Internal collaborators: 
Jindřich Hladil
Internal collaborators: 
Leona Chadimová
Internal collaborators: 
Ladislav Slavík

Fossil and recent organisms with accretionary skeletons show growth rhythms recognized as a record of changing seasons, days and nights, lunar cycles, and other changes gives a count of days per year and thus the rate of the Earth's rotation in the geological past. Measured data will be compared to astronomically computed ones and differences will be correlated with geotectonic events. The goal of the project is also to reconstruct the weather in the Palaeozoic: coral colonies were moved through storms or hurricanes, and their corallites then assumed different growth direction. As the year's growth periods are manifested as light and dark bands, we plan to compute the length of the periods between successive storms, and to determine the frequency of such events. The measurements can show the pattern of successive longer or shorter increments corresponding to favorable or less favorable conditions. Comparing of such patterns can lead to local sclerochronometry.