Size-frequency distributions of primary and secondary lunar impact craters.
Abstract
The graphs of diameter vs frequency plotted in the present study for primary impact craters produced in four time intervals exhibit an appreciable change in form with age. A deficiency of small craters relative to an extrapolation from the large-diameter parts of the curves is greatest and extends to the largest sizes in the oldest population (pre-Nectarian), whose curve approximates a log-normal form. Successively younger populations (Nectarian, Imbrian, Copernican plus Eratosthenian) have successively more small craters relative to larger ones and more nearly log-log distributions. Many of the craters thought to be small old primaries are here identified as secondary craters of basins, on the basis of previously developed criteria.
- Publication:
-
Lunar and Planetary Science Conference Proceedings
- Pub Date:
- 1978
- Bibcode:
- 1978LPSC....9.3735W
- Keywords:
-
- Frequency Distribution;
- Lunar Craters;
- Size (Dimensions);
- Statistical Distributions;
- Abundance;
- Chronology;
- Diameters;
- Least Squares Method;
- Morphology;
- Planetary Surfaces;
- Tables (Data);
- PRIMARY CRATERS;
- SECONDARY CRATERS;
- CRATERS;
- LUNAR;
- STRATIGRAPHY;
- BASINS;
- EJECTA;
- SIZE DISTRIBUTIONS;
- CRATER FORMATION;
- DIAMETER;
- METEOROID IMPACTS;
- Lunar and Planetary Exploration; Moon;
- Diameters:Moon Craters