JMDMT #1865 Microfossils of Cyanobacteria in Carbonaceous Meteorites

The James M. DuPont Meteorite Collection - be accounted for simply by loss of Si, and again favors mixing of compositionally diverse source components. Major element relations for the North American tektites suggests at least three compositional endmembers were involved in the target material. One endmember had high SiO2 and low total Fe-Mg-Al; this endmember is expressed best in georgiaites and a small group of samples from Barbados. Another endmember with relatively high MgO contents and high Mg/Fe ratios is required by the composition of DSDP Site 612 microtektites, and a third endmember is indicated by bediasite compositions characterized by relatively high Al2O3 and MgO contents