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

Abstract

Laterally continuous dark and orange microlaminations are observed in rock varnish from the northern TianGhan, Xinjiang. Microprobe chemical analyses indicate that dark layers in the varnish are rimh 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 paleoclimati data in the region.