Chemical Composition of Tektites

Abstract

IN a recent communication, Brian Mason1 asks that I supply a list of chemical compositions of sedimentary rocks which parallel those of the tektites. I offer the following references for his samples of tektites labelled A1–G1. The pages in the following list refer to Pettijohn's book on sedimentary rocks2: A1, 298; B1, 364; C1 319; D1; 319; E1, F1 and G1, 306. Except for water content, fair agreements between analyses can be secured by selecting analyses from these tables. The low water content of tektites is a real puzzle. There are some small differences in analyses between those listed by Pettijohn and the tektites. It is very probable that some granites of the composition listed by Mason are fused sediments. What would be more interesting than an argument about average sedimentary rocks would be a comparison of the composition of particular groups of tektites and sedimentary or igneous rocks in the general area in which the tektites are found. If cometary collisions melted the local rock and scattered the fragments over great distances3, it should be possible to find the original material at an appropriate place. But this requires study by an expert in these matters and probably additional observational data, and these cannot be supplied by me.