Fig. 5: Photomicrographs showing representative mineralogy and microstructures of typical lithologies. | Nature Communications

Fig. 5: Photomicrographs showing representative mineralogy and microstructures of typical lithologies.

From: Alpine-style nappes thrust over ancient North China continental margin demonstrate large Archean horizontal plate motions

Fig. 5

a The picritic-boninitic metabasite is predominately composed of large grains of hornblende with minor plagioclase; microphotograph shows a continuous view but left half is under cross polars and right half is under plane light; b microphotograph of the trondhjemite dike. The relict of original subhedral plagioclase phenocrysts corroborates the magmatic genesis for the precursor; c tholeiitic basalt is strongly foliated and chiefly composed of garnet (shown in d, e), biotite, amphibole, plagioclase, and quartz; d, e garnet forms rotated porphyroblast with sigmoidal and spiral-shaped inclusion trails making beautiful snowball garnet structures, which are traditionally interpreted as evidence for syntectonic crystallization; f schistes lustrés consisting of flaky chlorite, biotite, and prismatic orthoamphibole with plagioclase and quartz. bi biotite, chl chlorite, grt garnet, hbl hornblende, ilm ilmenite, orth-amph orthoamphibole, pl plagioclase.

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