Coal petrology of the Yimin Formation (Albian) in the Hailar Basin, NE China: Paleoenvironments and wildfires during peat formation

Coal seams preserve continuous and high-resolution records of paleoenvironments wildfire events during peat accumulation. In order to elucidate characteristics terrestrial climate changes the time accumulation, petrographic coals in Lower Cretaceous Yimin Formation (Albian) Jiuqiao Sag, Hailar Basin, NE China were studied. petrology analysis shows that studied coal are characterized by dominant huminite (average 80.0 vol.%, mmf-mineral matter free), secondary inertinite 19.9 mmf), a very low mineral content 0.8 vol.%). These results suggest developed under waterlogged conditions raised, ombrotrophic mires. The occurrence moderate values implies wildfires frequent Albian. Burning temperature, ranging from 273 379 °C inferred reflectances, indicates Albian ground fires because plant heights. Vertical trends compositional within may reflect local-scale, cyclic fluctuations development likely cause these was temperature rainfall. presence significant levels high atmospheric oxygen highly fire-prone period Basin. recurrent occurrences palaeo-wildfires succession Basin reinforce fire an important element affecting wetland biodiversity Albian, while diversification spread angiosperms taking place globally. Increased surface runoff erosion after Sag have enhanced flux availability nutrients sediments washing into fluvial, lacustrine, marine systems, further contributing dysoxic-anoxic events.