Identifying methane in soil

with a field spectroradiometer

NIR reflectance spectroscopy can be used to identify methane in soil. Spectral Evolution offers a range of field spectroradiometers including the SR-6500, RS-8800, RS-5400, PSR+, and RS-3500. These instruments cover the full spectral range from 350-2500 nanometers in rugged, lightweight units with no moving optical components for reliable field operation. Spectra of soils with methane show characteristic absorption features at 1180 and 1380 nanometers and from 1680-1720 and 2300-2450 nanometers. Different algorithms, modeling and chemometric techniques can be used to manipulate the spectral data acquired and build a library of known samples for comparison with new targets.

For ultra high resolution and high sensitivity spectra, the SR-6500 is unmatched among field units. The SR-6500 delivers the following resolution:

  • 1.5nm @ 700nm
  • 3.0nm @ 1500nm
  • 3.8nm @ 2100nm

The SR-6500 can be used with our Miniprobe to scan soil samples and identify minerals, especially clays and carbonates, in soil samples. Mineral identification is fast, easy and accurate with our optional EZ-ID software and three mineral spectral libraries . There is a sample methane spectra included in the USGS library for target matching.

In addition to soil analysis, the effects of methane in soil can also be indicated by changes in the red edge spectra of vegetation. The SR-6500 can be used for stand-off scanning of vegetation with a Field of View (FOV) lens or our unique leaf clip. The loss of chlorophyll in vegetation can be an indicator of methane microseepage.

The SR-6500 is an ultrea-high resolution spectroradiometer for field or laboratory use.

A scan of methane from the USGS library available with optional EZ-ID sample identification software.