Figure 3. Representative thin section microphotographs and scanning electron microscopic images of samples from the East Pilbara Terrane. Pilbara samples show complete serpentinization, yet their primary rock textures are preserved by serpentine pseudomorphs.a: Sample AW52614-4A shows compacted olivine-shaped serpentine clusters (ii) which locally form polygonal textures (featured by abundant 120° triple junctions). b: Alteration minerals such as chlorite, serpentine and magnetite occur in interstitial spaces(i) and veins in sample AW52614-4A (ii). Inc.ii, c.iii and c.iv, two sets of serpentine clusters are recognized with the cross-polarized light photomicrographs. One set shows black/dark grey color, with outlines similar to olivine grains. Another set is in white/light grey, which appears to enclose the serpentine clusters of the first set. This texture resembles cumulate textures, where smaller chadacrysts could be included in larger oikocrysts. Mineral abbreviations: chl: chlorite; Cr-sp: Cr-spinel; mag: magnesite; mgt: magnetite; ol: olivine; opx: orthopyroxene; serp: serpentine;
Table 1: Mineralogy and location information of investigated samples.