U.S. Geological Survey home page

USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
For more information on the library, see: local link web link

TITLE: Grass_AETR95 CA01-AETR-1 NPV DESCRIPT

DOCUMENTATION_FORMAT: PLANT

SAMPLE_ID: CA01-AETR-1

PLANT_TYPE: Grass

PLANT: Barbed goatgrass

LATIN_NAME: Aegilops triuncialis L.

COLLECTION_LOCALITY: Garden Valley area, in El Dorado county, approximately 60 km northeast of Sacramento, California

COLLECTION_LATITUDE: 38.842405 deg. N

COLLECTION_LONGITUDE: 120.884117 deg. W

DATUM: WGS-84

ORIGINAL_DONOR: Raymond F. Kokaly, USGS

SAMPLE_DESCRIPTION:

This spectrum is the average reflectance of 14 field measurements of an area of barbed goatgrass (Aegilops triuncialis). The measurements were made at 11:00 am local time on September 6, 2001. These spectra were made using an ASD FullRange spectrometer (model 653) in reflectance mode, relative to a Spectralon reference panel. The bare fiber of the spectrometer was used to measure the reflectance spectra of the grass. The grass was a light brown color and in a dry, non-photosynthetic vegetative (NPV) state. Gray and brown litter dominated the space between the remnant grass stems. The standing dead grass and litter had a combined cover of 95%. The remaining surface cover was shadow and exposed soil, with 2.5% cover each. The fiber optic cable was pointed at nadir and held at waist height while walking around the grass area during the measurement. The instrument was programmed to record 6 second averages of reflectance (thus, each recorded spectrum was an average of 60 individual measurements). An average spectrum was computed from the recorded measurements and converted to absolute reflectance by multiplying by the reflectance spectrum of the Spectralon reference panel. Other spectra, of a grass/rock area and of buckbrush, were also measured in this area and are included in this spectral library, sample names: CA01-AETR-2, CA01-CECU-1, CA01-CECU-2 and CA01-CECU-3.

This spectrum was used in the following publication:
Swayze, G.A., Kokaly, R.F., Higgins, C.T., Clinkenbeard, J.P., Clark, R.N., Lowers, H.A, Sutley, and S.J., 2009, Mapping potentially asbestos-bearing rocks using imaging spectroscopy, Geology Volume 37, pages 763-766. http://dx.doi.org/10.1130/G30114A.1

IMAGE_OF_SAMPLE: Photo of site Photo of site Photo of site Photo of site

END_SAMPLE_DESCRIPTION.

COMPOSITIONAL_ANALYSIS_TYPE: None

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

TRACE_ELEMENT_ANALYSIS:

TRACE_ELEMENT_DISCUSSION:

END_TRACE_ELEMENT_DISCUSSION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns