Rock varnish microlaminations from northern Tianshan, Xinjiang and their paleoclimatic implications

Laterally continuous dark and orange microlaminations are observed in rock varnish from the northern Tianshan, Xinjiang. Microprobe chemical analyses indicate that dark layers in the varnish are rich in Mn and orange layers are poor in Mn. Microscopic examinations of varnish ultra-thin sections reveal a lamination pattern that is regionally consistent and comparable. Based on geomorphic age control, the Holocene varnish lamination sequence is tentatively established and its paleoclimatic implications are explored within the framework of existing paleoclimatic data in the region.