The problem of the origin of symplectites in olivine-bearing lunar rocks

In a study of its origin in olivine-bearing lunar rocks, symplectite is grouped into the following types: (1) very abundant blebs in olivine phenocrysts, (2) scattered blebs in dunite, (3) scattered elongated masses along grain boundaries in troctolite, (4) scattered mosaic assemblages of coarser minerology along grain boundaries, (5) very abundant needle-like arrays, and (6) very abundant grains dispersed in rows. Four theories are proposed to explain the various symplectite distributions.