YANG W T,FENG W Y,ZHANG H Y,et al.Triassic climate and its evolution characteristics in Jiyuan Area，South of North China Plate：Evidence from paleosol geochemistry[J].Journal of Henan Polytechnic University( Natural Science),doi:10.16186/j.cnki.1673-9787. 2023100013.

Received：2023-10-16

Revised：2023-12-04

Online：2024-01-24

Triassic climate and its evolution characteristics in Jiyuan Area，South of NorthChina Plate:Evidence from paleosol geochemistry

YANG Wentao，FENG Wanying，ZHANG Hongyu，WANG Min

（School of Resources and Environment，Henan Polytechnic University，Jiaozuo 454000，Henan，China）

Abstract: Objective The Triassic was in a period of rapid fluctuation of greenhouse climate，and the paleo⁃sol recorded abundant paleoclimate information. To study the climate change process from extreme to me⁃dium greenhouse，Methods the Triassic paleosoils in the Jiyuan area were selected for major chemical composition.The mean annual precipitation and mean annual temperature were estimated to reconstruct the paleoclimate and its evolution.Results The results show that 15 layers of paleosol（including calcareous soil，or⁃ganic soil and gleyed soil） are identified in the Triassic strata in Jiyuan area.The mean annual precipitationin the Jiyuan area during the Triassic was 447~1 557 mm/a，and the mean annual temperature was 11~23 ℃.In the Early Triassic，the mean annual precipitation was 447~896 mm，and elevated precipitation oc⁃curred in the late time. The mean annual temperature was 16~23 ℃ ，showing a downward trend. In the Middle Triassic，the mean annual precipitation was 679~1 539 mm/a，showing an increasing trend.The meanannual temperature was 11~20 ℃，and the low value occurred in the middle stage.In the Late Triassic，themean annual precipitation was 575~1 557 mm/a，with lower values in the early and late stages，and high values in the middle stage. Triassic climate fluctuation was relatively common in the south of North China.There was a relatively wet period in the Early Triassic，an overall wetting trend occurred in the Middle Triassic，and the Late Triassic also had dry periods.Conclusion These data can provide reference for the Trias⁃sic climate evolution.

Key words：Triassic；climate evolution；geochemistry；Jiyuan Area

CLC: P59