Vibrational spectroscopy of calcic amphiboles - applications for exploration and mining

Laukamp, Carsten; Termin, Kathrin Anna; Pejcic, Bobby; Haest, Maarten; Cudahy, Thomas

doi:10.1127/0935-1221/2012/0024-2218

Cited by 31 publications

(23 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Amphibole spectra (Figure 2b ) are characterized by an OH overtone at 1.395 μm and Fe/Mg‐OH combination bands at 2.25, 2.31–2.32 μm and 2.39–2.40 μm (Laukamp et al., 2012 ; Mustard, 1992 ). Although the 2.31–2.32 μm absorption feature overlaps with other minerals, the ∼2.39 μm feature is only present in a few minerals, the others being talc and saponite, which are rare in the spectroscopy data set.…”

Section: Resultsmentioning

confidence: 99%

“…Although the 2.31–2.32 μm absorption feature overlaps with other minerals, the ∼2.39 μm feature is only present in a few minerals, the others being talc and saponite, which are rare in the spectroscopy data set. Amphibole spectra in these cores typically have a 2.12 μm feature, which helps distinguish them from talc (Laukamp et al., 2012 ), though mixing and low abundances of amphibole may prevent detection of this feature.…”

Section: Resultsmentioning

confidence: 99%

“…Chlorite (Figure 2c) is identified by the presence of the OH overtone at ∼1.39 μm and metal-OH combination absorptions at 2.25 μm and principal absorption centered from 2.33 to 2.35 μm, with position dependent 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 1.0 1 .5 2.0 2 .5 on Mg/Fe content (e.g., Bishop et al, 2008;Clark, King, et al, 1990). The absence of an absorption feature at 2.39 μm distinguishes pixels containing chlorite from amphibole (e.g., Laukamp et al, 2012). Although chlorite and amphibole commonly occur together in the core, chlorite is difficult to identify where amphibole is present because the absorption features in chlorite also are present in amphibole (which has the additional 2.39 μm feature), and we therefore do not map chlorite in pixels where amphibole is identified.…”

Section: Infrared Spectral Signaturesmentioning

confidence: 99%

“…( 1990 ); Hunt and Ashley ( 1979 ) BD2050pyx 2.05 1.67, 2.51 7/3/3 Fe 2+ in high Ca pyroxene (e.g., augite, diopside) Cloutis and Gaffey ( 1991 ) BD2106 2.106 2.015, 2.21 If present with 1.7 micron feature, suggests organics/non‐rock n/a BD2150pyx 2.15 1.67, 2.51 7/3/3 Fe 2+ in high Ca pyroxene (e.g., augite, diopside) Cloutis and Gaffey ( 1991 ) BD2120 2.12 2.094, 2.170 3/3/3 Feature in amphibole Laukamp et al. ( 2012 ); Mustard ( 1992 ) BD2200 2.206 2.134, 2.237 3/3/3 Al‐OH/Si‐OH Aines and Rossman ( 1984 ); Anderson and Wickersheim ( 1964 ); Bishop et al. ( 2002 ); Clark, King, et al.…”

Section: Table A1mentioning

confidence: 99%

See 3 more Smart Citations

Hydrothermal Alteration of the Ocean Crust and Patterns in Mineralization With Depth as Measured by Micro‐Imaging Infrared Spectroscopy

et al. 2021

View full text Add to dashboard Cite

Imaging spectroscopy efficiently and effectively mapped spatial patterns in hydrothermal alteration mineral occurrence in ocean crust core  Samail ophiolite upper ocean crust cores are dominated by chlorite, amphibole, and epidote, while deeper cores have more zeolite/prehnite  Hydrothermal alteration largely decreases with depth in the ocean crust but is locally intense in major fault zones, even in lower crust Accepted ArticleThis article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Infrared Spectral Signaturesmentioning

confidence: 99%

Section: Table A1mentioning

confidence: 99%

See 2 more Smart Citations

Hydrothermal Alteration of the Ocean Crust and Patterns in Mineralization With Depth as Measured by Micro‐Imaging Infrared Spectroscopy

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Prominent absorption features in both tremolite and talc occur near 1.39 μm, 2.3 μm, and 2.39 μm (Table 1; Fig. 2), but these show significant overlap (Laukamp et al, 2012). These three regions also are affected by interference from carbonates and other hydrous Mg-silicates (Fig.…”

Section: Tremolite and Talcmentioning

confidence: 99%

Mapping metamorphic hydration fronts with field-based near-infrared spectroscopy: Teakettle Junction contact aureole, Death Valley National Park (California, USA)

Duke

2020

Geosphere

View full text Add to dashboard Cite

Mineral distribution in a previously undescribed contact aureole in siliceous dolomite at Teakettle Junction, Death Valley National Park (California, USA), was mapped with a handheld visible and near-infrared (Vis-NIR, 0.35–2.5 μm) spectrometer. With increasing distance from a small Jurassic(?) pluton, the following mineral zones occur: periclase (hydrated to brucite), forsterite (variably hydrated to serpentine and typically accompanied by clinohumite), tremolite, and talc. Airborne Vis-NIR imaging spectrometer data with 5 m ground resolution shows serpentine and tremolite distribution in close agreement with the field data. Field measurements show dolomite and calcite throughout the study area, along with minor amounts of phlogopite and illite. Hydrous minerals were detected in field measurements at levels on the order of 1 vol%. Phlogopite, talc, and illite crystals in many samples are <20 μm in size and difficult to identify without scanning electron microscopy examination. Sensitivity of Vis-NIR spectroscopy to hydrous minerals is especially important in the context of metamorphic fluid flow. Significant hydration of wall rocks is limited to samples between the pluton contact and the serpentine (forsterite) isograd as shown by mineral distribution and variation in the depth of the OH absorption feature near 1.4 μm. This boundary is interpreted to represent a metamorphic hydration front beyond which there was minimal infiltration of wall rocks by H2O-rich fluid. Within this zone of hydration, however, the extent of hydration is highly variable, even at individual sample sites with samples spaced on the order of 1 m or less. Heterogeneity of fluid-rock interaction at this scale must be considered in models of heat and mass transfer accompanying contact metamorphism.

show abstract

Hyperspectral Proximal Sensing Instruments and Their Applications for Exploration Through Cover

Laukamp

LeGras

Lau

2021

Portable Spectroscopy and Spectrometry

View full text Add to dashboard Cite

Vibrational spectroscopy of calcic amphiboles - applications for exploration and mining

Cited by 31 publications

References 24 publications

Hydrothermal Alteration of the Ocean Crust and Patterns in Mineralization With Depth as Measured by Micro‐Imaging Infrared Spectroscopy

Hydrothermal Alteration of the Ocean Crust and Patterns in Mineralization With Depth as Measured by Micro‐Imaging Infrared Spectroscopy

Mapping metamorphic hydration fronts with field-based near-infrared spectroscopy: Teakettle Junction contact aureole, Death Valley National Park (California, USA)

Hyperspectral Proximal Sensing Instruments and Their Applications for Exploration Through Cover

Contact Info

Product

Resources

About