Statistical tests of a periodicity hypothesis for crater formation rate  II
Abstract
A statistical test is made of the periodicity hypothesis for crater formation rate, using a new data set compiled by Grieve. The criterion adopted is that of Broadbent, modified so as to take into account the loss of craters with time. Small craters (diameters <=2 km) are highly concentrated near the recent epoch, and are not adequate as a data set for testing. Various subsets of the original data are subjected to the test and a period close to 30 Myr is detected. On the assumption of random distribution of crater ages, the probability of detecting such a period is calculated at 50, 73 and 64 per cent respectively for craters with <e1>D<~</e1>2 km (N=49), for those with 10>=<e1>D<~</e1>2 km (N=31) and for large craters [<e1>D<~</e1>10 km, (N=18)] (where N is the number of craters). It is thus difficult to regard the detected period as being significant based on statistical argument alone. It is pointed out that a similar period is associated with geometric reversals and the climatic variation as revealed by the deep ocean delta^18O spectrum.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 April 1996
 DOI:
 10.1093/mnras/279.3.727
 Bibcode:
 1996MNRAS.279..727Y
 Keywords:

 METHODS: STATISTICAL;
 COMETS: GENERAL;
 SOLAR SYSTEM: GENERAL