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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: Oak QUDU CA01-QUDU-1 bush 1 DESCRIPT

DOCUMENTATION_FORMAT: PLANT

SAMPLE_ID: CA01-QUDU-1

PLANT_TYPE: California chaparral plant, perennial shrub

PLANT: Leather Oak

LATIN_NAME: Quercus durata Jeps.

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 29 field measurements of a leather oak bush (Quercus durata). The measurements were made at 3 pm local time on September 5, 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 bush. The leaves were green and small (1 to 2 cm in length) and curled at the edges, probably due to water stress. The tops of the leaves were dusty. The bush was approximately 1 meter in height. On average the field of view of the spectrometer included 70% green leaves, 10% branches and stems, 15% shadows, and 5% background soil/rock/litter. The fiber optic cable was pointed at nadir and held 30 cm above the top of the plant and moved around 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 samples of leather oak were also measured, near this one, and are included in this spectral library, sample names: CA01-QUDU-2 and CA01-QUDU-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

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