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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Limestone CU02-11A DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: CU02-11A

MIXTURE_TYPE: Intimate

MIXTURE: Limestone

FORMULA: CaCO3 + impurities

FORMULA_HTML: CaCO3 + impurities

COLLECTION_LOCALITY: 6 km north of western center, Cuprite, Nevada, USA

ORIGINAL_DONOR: Gregg Swayze

COLLECTION_LATITUDE: N37 36.908' # degrees and decimal minutes (N or S)

COLLECTION_LONGITUDE: W117 14.393' # degrees and decimal minutes (W or E) P> DATUM: NAD27 # coordinate datum

CURRENT_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: U.S.G.S. Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

This sample was collected from a large outcrop of the Cambrian Mule Springs Limestone exposed about 6 km north of the western alteration center at Cuprite, NV. The surface measured spectrally is the weathered surface of the sample.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

calcite (major), quartz (trace)

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: XRF # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

None

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

The spectrum has absorptions that are characteristic of calcite with a main C-O related absorption at 2.3391 microns. The monotonic negative slope toward shorter wavelengths may be caused by oranic impurities.

See: Swayze, G.A., 1997, The hydrothermal and structural history of the Cuprite Mining District, southwestern Nevada: an integrated geological and geophysical approach: unpublished Ph.D. Dissertation, University of Colorado at Boulder, 399p.

END_SPECTROSCOPIC_DISCUSSION.

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

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib05a r 8575 0.2-3.0µm 200 g.s.=


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