226 Quaternary Research to Characterize Environmental and Geological Hazards (Posters)

Quaternary geosciences research features many valuable tools for understanding environmental and geologic hazards. This multidisciplinary session seeks presentations that encompass a wide range of processes and environments relevant to managing critical infrastructure and resources.

Tuesday, 21 October 2025
8:00 AM - 5:30 PM
HBGCC, Hall 1

Preliminary Results on Dating Maar Eruption in the Clear Lake Volcanic Field using Luminescence Dating

Paper number: 226-1
Program: Technical Sessions
Time: 8:00 AM – 8:00 AM

Authors

Abstract

The Clear Lake Volcanic Field in northern California has experienced explosive volcanic activity over the past 2.1 million years, with the most recent eruptions forming phreatomagmatic maars along the margins of Clear Lake. The timing of these eruptions remains poorly constrained due to a lack of datable material and the complex depositional environments associated with maar tephra. While radiocarbon dating suggests that several eruptions occurred between ~8,500 and 13,000 years BP, it remains unclear whether additional eruptions took place within the last 2,000–3,000 years as suggested by oral histories of local Indigenous communities. Additionally, radiocarbon ages may be affected by the reservoir effect, resulting in erroneously old ages.

We have refined eruption chronology by applying single-aliquot regenerative post-infrared infrared stimulated luminescence (post-IR IRSL) dating of K-feldspar grains, in conjunction with existing radiocarbon ages, to several maar craters along the edge of Clear Lake. These luminescence ages provide preliminary constraints on the timing of the most recent maar eruptions. Improving the understanding of eruption timing and dynamics contributes to a more complete eruptive history for the area and informs future volcanic hazard assessments and monitoring strategies in this region.

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

doi: 10.1130/abs/2025AM-414334

© Copyright 2025 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.