Method development and validation for microscopic measurement of the fluorescence spectrum of sedimentary organic matter in geologic samples

Kavin Wee Siaw; Paul C. Hackley

doi:10.1016/j.mex.2026.104003

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Method development and validation for microscopic measurement of the fluorescence spectrum of sedimentary organic matter in geologic samples

Kavin Wee Siaw·Paul C. Hackley

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Abstract

The goal of this study was to develop and validate a standard operating procedure for measuring the fluorescence emission of sedimentary organic matter (SOM), a proxy used to assess thermal maturity conditions in petroliferous basins. We tested the performance of a spectrometer integrated with an epi-fluorescence imaging microscope, and evaluated instrument calibration, dark-current correction, time duration for instrument stabilization, light delivery optimization, and the number of measurements necessary to optimize precision. These tests were used to guide instrument operation, ensure measurement accuracy, and characterize performance limitations of the system as SOM transitions to higher thermal maturity with accompanying signal deterioration. Adhering to these newly established guidelines enhances the reproducibility of fluorescence spectroscopy measurements. More importantly, this work endeavors to reach the overall objective of demonstrating the utility of fluorescence spectroscopy for evaluating the thermal maturity of SOM. Method for fluorescence spectroscopy of sedimentary organic matter. Internal calibration via diffuse halogen light reflected from polytetrafluoroethylene (PTFE). Evaluates emission response via λ max and red-green and blue-green quotients.

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Kavin Wee Siaw, Paul C. Hackley. 2026-06-17. Method development and validation for microscopic measurement of the fluorescence spectrum of sedimentary organic matter in geologic samples. https://doi.org/10.1016/j.mex.2026.104003

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