Multi-proxy records of wildfires and climate-vegetation-wildfire interactions during the Middle Jurassic of the Santanghu Basin, northwest China

Zhou, Jiamin, Shao, Longyi, Jones, Tim ORCID: https://orcid.org/0000-0002-4466-1260, Huang, Yangyang, Chen, Mengran, Ma, Yuedong and Lu, Jing 2025. Multi-proxy records of wildfires and climate-vegetation-wildfire interactions during the Middle Jurassic of the Santanghu Basin, northwest China. Palaeogeography, Palaeoclimatology, Palaeoecology 679 , 113260. 10.1016/j.palaeo.2025.113260 Item availability restricted.

PDF - Accepted Post-Print Version Restricted to Repository staff only until 10 September 2026 due to copyright restrictions. Download (382kB)

Abstract

Palaeowildfires have played an important role in terrestrial ecosystems since the evolution of land plants, and are a significant disturbance factor in many of the Earth's ecosystems. The Middle Jurassic was a period of rapid climatic fluctuations, and there is abundant evidence that wildfires were frequent at that time. The Santanghu Basin has Middle Jurassic inertinite-rich coals that are a source of high-quality information about palaeowildfires and palaeoenvironments; these provide an opportunity to study deep-time palaeowildfire evolution and their ecological effects. To better understand palaeowildfire events, a multi-proxy study was undertaken that analyzed coal macerals, inertinite reflectance, and polycyclic aromatic hydrocarbons (PAHs) in coal and mudstone samples from the Aalenian Santanghu Basin. In addition, normal alkanes (n-alkanes) were used as biomarkers of alterations in coal-forming vegetation, and natural char was used as complementary coal petrological evidence for palaeowildfires. The presence of high levels of inertinite, high natural char content, and high abundances of potentially combustion-derived PAHs demonstrate that multiple, widespread wildfires occurred during the Aalenian in the Santanghu Basin. Inertinite reflectance values ranging from 1.34 % to 2.67 %Ro indicate that palaeowildfires were dominated by lower temperature ground fires, with a small proportion of higher temperature crown fires. It is believed that the total amount of PAHs can be used as good evidence of palaeowildfires, but the ratios of high to low ring PAHs in the molecules are not necessarily indicative of combustion temperatures of palaeowildfires due to the extreme instability of low-ring PAHs. It is proposed that the abundant inertinites in Jurassic coals were accumulated as the result of a multi-factorial coupling; palaeoclimate was the main driver, paleo vegetation and gelified organic matter provided the fuel, and palaeowildfires were indirectly the mechanism of preservation. Furthermore, a potential mechanism has been proposed for wildfire activity to influence the growth of aquatic plants.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Schools > Earth and Environmental Sciences
Publisher:	Elsevier
ISSN:	0031-0182
Date of First Compliant Deposit:	8 October 2025
Date of Acceptance:	1 September 2025
Last Modified:	09 Oct 2025 11:00
URI:	https://orca.cardiff.ac.uk/id/eprint/181540

Actions (repository staff only)

Edit Item