178 Paleontology, Diversity, Extinction, Origination

Tuesday, 21 October 2025
8:00 AM - 12:00 PM
HBGCC, 305

High-Paleolatitude Glossopterid Forest Destruction and Recovery Associated with Felsic Volcanism in the Sydney Basin, Australia

Paper number: 178-5
Program: Technical Sessions
Time: 9:15 AM – 9:30 AM

Authors

Abstract

Dispersed siliceous permineralized wood is abundant in middle to upper Permian continental strata of the high-palaeolatitude Sydney Basin, eastern Australia. Anatomical studies of these woods provide extensive information on the taxonomic affinities, diversity, and palaeobiology of the original plants, and their interactions with terrestrial arthropods and microbes. However, very few cases of individual upright stumps or in situ fossil forests have been reported from the Permian strata of Gondwana to evaluate the stature, density, age profile, and palaeoclimatic signature of the coal-producing vegetation. Here, we document multiple horizons in the northern Sydney Basin hosting in situ stumps rooted in coal seams and buried by overlying thick felsic tuff beds. These polar forests were of low-diversity, dominated by glossopterid gymnosperms, and similar in stature to modern boreal forested mire vegetation, with tree densities of over 1300 trunks per hectare. Multiple intercalated coal and tuff beds hosting upright stumps in individual stratigraphic sections indicate repeated burial events and recolonization of the land surface by forested mire vegetation on decadal to centennial time scales. The intensive convergent-margin-related volcanism appears to have provided little impediment to the survival and persistence of the glossopterid coal-forming vegetation through the Guadalupian to Lopingian in this humid high-latitude region. Seasonal growth rings are prominent in the wood and sporadic false rings attest to episodic intraseasonal perturbations to growth, likely caused by episodic ash falls or herbivore/pathogen attack.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6

doi: 10.1130/abs/2025AM-413945

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