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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: Melting_snow DESCRIPT

DOCUMENTATION_FORMAT: VOLATILE

SAMPLE_ID: mSnw1a, mSnw3, mSnw4, mSnw5, mSnw8, mSnw9, mSnw12, mSnw14, mSnw15, mSnw16

MATERIAL_TYPE: Oxide

MATERIAL: Water_Ice (snow, slush)

FORMULA: H2O

FORMULA_HTML: H2O

COLLECTION_LOCALITY: Genesse area, Colorado

COLLECTION_LATITUDE: Not Available # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: Not Available # degrees and decimal minutes (W or E)

DATUM: Not Available # coordinate datum

ORIGINAL_DONOR: Trude King

CURRENT_SAMPLE_LOCATION: Not Available

ULTIMATE_SAMPLE_LOCATION: Not Available

SAMPLE_DESCRIPTION:

This sample of fresh Colorado snow was collected in an ice chest an brought into the laboratory where is slowly melted over a period of a couple of hours. The initial snow depth was approximately 30 cm (1 foot). The sequence shows the change in the ice/water mix. From the pure white color of the snow, and the fact that the melted residual was very clear, we estimate that the snow had less than 1 ppm particulate contamination. Spectrum at mSnw16 had a puddle of approximately 3 cm of water on top of the snow (2-way optical path ~ 6cm). The sample was discarded after the spectral measurements were complete.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

none

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

No additional compositional details available.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

not available

END_MICROSCOPIC_EXAMINATION.

IMAGE_OF_SAMPLE: Not Available

SPECTROSCOPIC_DISCUSSION:

Classic water absorptions, both frozen and liquid are seen in these spectra. Because of water vapor rising from the sample and changing rapidly with time, small segments of the 1.4, 1.9 and > 2.3 micron region have been deleted, as the data were not corrected for the atmospheric interference. No other materials are indicated in these spectra, so the spectral purity in this region is an a.

END_SPECTROSCOPIC_DISCUSSION.

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