Australasian tektite geographic pattern, crater and ray of origin, and theory of tektite events

Chemical data recently obtained on 18 major and minor elements in 507 tektites from 205 localities are used to map the geographic distribution pattern of Australasian tektites. Areas of distinct chemical type outline a coarse structure to the pattern: an elongate zone of HCa tektites stretching northwest across Australia, a crescent zone of HMg tektites curving from Australia to Indonesia to the Philippines, and a teardrop-shaped, zone of normal indochinites arcing northeast over Southeast Asia. Various sets of matching polygons of specific gravity and matching chemical analyses of individual specimens define a fine structure compatible with this coarse structure. The over-all pattern is not radial, as would be required for a terrestrial origin, but is systematically curved. Numerous moon-to-earth trajectories were computed for ejecta leaving various lunar craters in a search for compatible places of origin. It was found that the complex tektite distribution pattern is matched by the trajectory landing pattern for ejecta leaving Tycho, and that the required heading direction for this ejecta coincides with one of Tycho's most prominent rays. From a study of visible elements comprising this and other similar rays, a ‘connate crater’ theory of tektite events is formulated which offers a reconciliation of certain tektite observations previously considered contradictory. Some implications to selenology, and comparisons with Apollo data (especially with rock 12013), are briefly discussed.