In:
Geological Journal, Wiley, Vol. 58, No. 7 ( 2023-07), p. 2727-2741
Abstract:
Petrography and geochemical data of the Late Cretaceous clastic rocks in the northern Songliao Basin were used to infer the provenance and chemical weathering history. Petrographic data indicates that the composition of the sandstones is mainly quartz (34.48–50.43%), feldspars (14.16%–24.07%) and lithic fragments (33.91%–45.9%). Similar REE patterns and trace element ratios suggest that both the sandstones (La CN /Yb CN = 12.97; Eu/Eu* = 0.81; Th/Sc = 1.10) and mudstones (La CN /Yb CN = 10.02; Eu/Eu* = 0.71; Th/Sc = 1.10) were derived from a similar source area with felsic volcanic rocks as dominant contributors. The main provenance area is probably the eastern Zhangguangcai Range, the north‐eastern Lesser Xing'an Range and the south‐eastern Songliao Basin. A modelled mixture composed of 65% granodiorite in the Lesser Xing'an Range, 30% granite in Zhangguangcai Range and 5% epidiorite in the south‐eastern Songliao Basin, can be interpreted as the potential source compositions for the clastic sediments. This conclusion is reinforced by the major element of geochemistry composition and sandstone petrography. Relatively low Chemical Index of Alteration (CIA) values in mudstones (48.14–69.26) and sandstones (50.78–59.96) indicate mild chemical weathering conditions in the source area. The chemical weathering history suggests that a cold and arid climate prevailed during the Late Cretaceous.
Type of Medium:
Online Resource
ISSN:
0072-1050
,
1099-1034
Language:
English
Publisher:
Wiley
Publication Date:
2023
detail.hit.zdb_id:
1479201-1
SSG:
13
