Synchrotron Infrared Microspectrometry Applied to Petrography in Micrometer-Scale Range: Fluid Chemical Analysis and Mapping

Abstract

The potentiality of synchrotron infrared microspectrometry was investigated for in situ analysis of fluid inclusions and volatiles of particular geological interest. Thanks to the intrinsic high brightness of the synchrotron infrared source, areas as small as a few μm2 can be probed, providing a high-contrast analysis of small inclusions in geological materials. We have identified organic components in such small volumes in their liquid and gaseous phase, thus allowing a deeper analysis of oil-water inclusions entrapped in diagenetic cements. Such detailed analysis opens up new perspectives in petroleum reservoir evolution studies. The high signal-to-noise ratio of spectra obtained in small volume allows a fast and accurate chemical mapping of the inclusion components. Drastic refraction effects preclude, at the present state, a quantitative analysis of either the volume or the thickness of the individual inclusions. Traces of volatiles such as CO2 and H2O are easily detected in the vitreous and gaseous part of the glass melt fluid inclusions. We have also profiled the hydroxyl concentration near a wall, and calculated the hydrogen diffusion coefficient in anhydrous minerals such as diopside.

Synchrotron FTIR Hydrocarbon Fluid Inclusion Microanalysis Applied to Diagenetic History and Fluid Flow Reconstruction in Reservoir Appraisal

“…The systematic coexistence of oil and aqueous FI's in overgrowth (Guilhaumou et al, 1998b) confirms that basinal fluids and light hydrocarbons depleted in CO 2 were both present when silicification began. Thus hydrocarbon migration had already started.…”

Challenges in Biology and Medicine with Synchrotron Infrared Light

“…The high brightness of infrared synchrotron radiation has impacted the field of infrared microspectroscopy in a variety of scientific disciplines, including hard and soft condensed matter [26,28], geology [29], and biology . The principal motivation for synchrotron-based IR microspectroscopy is to achieve significantly greater lateral resolution (typically at the diffraction limit) while recording data of superior signal-to-noise characteristics without resorting to prohibitively long acquisition times.…”

FTIR Microspectroscopy of Polymeric Systems

“…Hence, data collection over wide spectral ranges is considerably faster and sensitivity for thin samples is excellent. Apertures as low as 3¥3 µm 2 have been used [128]. However, the major drawback arises from the unique component of the technique: a synchrotron source is required.…”