scholarly journals Twenty Years of ASTER Contributions to Lithologic Mapping and Mineral Exploration

2019 ◽  
Vol 11 (11) ◽  
pp. 1394 ◽  
Author(s):  
Michael Abrams ◽  
Yasushi Yamaguchi
Keyword(s):  
Thermal Emission ◽  
Surface Composition ◽  
Mineral Exploration ◽  
Wavelength Region ◽  
Thermal Infrared ◽  
Optical Data ◽  
Sufficient Information ◽  
Infrared Band ◽  
Quartz Content ◽  
Joint Project

The Advanced Spaceborne Thermal Emission and Reflection Radiometer is one of five instruments operating on the National Aeronautics and Space Administration (NASA) Terra platform. Launched in 1999, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) has been acquiring optical data for 20 years. ASTER is a joint project between Japan’s Ministry of Economy, Trade and Industry; and U.S. National Aeronautics and Space Administration. Numerous reports of geologic mapping and mineral exploration applications of ASTER data attest to the unique capabilities of the instrument. Until 2000, Landsat was the instrument of choice to provide surface composition information. Its scanners had two broadband short wave infrared (SWIR) bands and a single thermal infrared band. A single SWIR band amalgamated all diagnostic absorption features in the 2–2.5 micron wavelength region into a single band, providing no information on mineral composition. Clays, carbonates, and sulfates could only be detected as a single group. The single thermal infrared (TIR) band provided no information on silicate composition (felsic vs. mafic igneous rocks; quartz content of sedimentary rocks). Since 2000, all of these mineralogical distinctions, and more, could be accomplished due to ASTER’s unique, high spatial resolution multispectral bands: six in the SWIR and five in the TIR. The data have sufficient information to provide good results using the simplest techniques, like band ratios, or more sophisticated analyses, like machine learning. A robust archive of images facilitated use of the data for global exploration and mapping.

scholarly journals A Remote-Sensing-Based Alteration Zonation Model of the Duolong Porphyry Copper Ore District, Tibet

2021 ◽  
Vol 13 (24) ◽  
pp. 5073
Author(s):  
Fojun Yao ◽  
Xingwang Xu ◽  
Jianmin Yang ◽  
Xinxia Geng
Keyword(s):  
Remote Sensing ◽  
Thermal Emission ◽  
Mineral Exploration ◽  
Porphyry Copper ◽  
Principal Component ◽  
Thermal Infrared ◽  
Copper Ore ◽  
Aster Data ◽  
Alteration Zoning ◽  
Ore District

Remote sensing (RS) of alteration zones and anomalies can provide information that is useful for geological prospecting and exploration. RS is an effective method for porphyry copper mineral exploration and prospecting prediction. More specifically, the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) data, which include 14 spectral channels from visible light to thermal infrared, are useful in such cases. This study uses visible-shortwave infrared and thermal infrared ASTER data together with surface material spectra from the Duolong porphyry copper ore district to construct an RS-based alteration zonation model of the deposit. In this study, an RS alteration zoning model is established based on ground-spectral alteration zoning results. The methods include PCA (Principal Component Analysis), Ratio, and Slope methods. The information obtained by each method is different. RS-based alteration zonation is developed based on the intersection of maps, resultant from the different methods for extracting information related to different minerals. The alteration zonation information extracted from ASTER RS data is consistent with geological observations. Using information from the RS-based model, we mapped the alteration minerals and zones of the Duolong ore district, thereby identifying prospecting target areas of the deposit.

scholarly journals IDENTIFICATION OF ROCKS AND THEIR QUARTZ CONTENT IN AMARKANTAK, INDIA USING ASTER TIR DATA

2018 ◽  
Vol XLII-5 ◽  
pp. 255-259 ◽  
Author(s):  
S. Guha ◽  
H. Govil ◽  
M. Tripathi ◽  
M. Besoya
Keyword(s):  
Thermal Emission ◽  
Mineral Exploration ◽  
Atmospheric Correction ◽  
Sedimentary Rocks ◽  
Interaction Strength ◽  
Principal Component ◽  
Quartz Content ◽  
Important Indicator ◽  
Analysis Technique ◽  
Organic Particles

<p><strong>Abstract.</strong> Quartz (SiO<sub>2</sub>) abundance in rock is an important indicator of mineralization in many metal deposits and quartz detection has a great role in mineral exploration. The present study identified the quartz contained rocks in Amarkantak region, India applying thermal infrared bands (bands 10–14) of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image. After atmospheric correction, principal component analysis technique was applied on the TIR bands and the resulting principal component images were analyzed. The three optimal principal components were selected based on the spectral interaction strength and the eigenvalues of each band of the ASTER data. The result presented that extrusive igneous rock and carbonate sedimentary rocks are quartz-poor while sedimentary rocks made up of organic particles and sandstone is quartz-rich.</p>

scholarly journals INFRARED CEPHALIC-VEIN TO ASSIST BLOOD EXTRACTION TASKS: AUTOMATIC PROJECTION AND RECOGNITION

2017 ◽  
Vol XLII-2/W4 ◽  
pp. 193-197
Author(s):  
S. Lagüela ◽  
M. Gesto ◽  
B. Riveiro ◽  
D. González-Aguilera
Keyword(s):  
Computer Vision ◽  
Infrared Image ◽  
Thermal Infrared ◽  
Cephalic Vein ◽  
Automatic Identification ◽  
Infrared Band ◽  
Thermographic Camera ◽  
Close Range ◽  
Vein Recognition ◽  
Thermal Infrared Imagery

Thermal infrared band is not commonly used in photogrammetric and computer vision algorithms, mainly due to the low spatial resolution of this type of imagery. However, this band captures sub-superficial information, increasing the capabilities of visible bands regarding applications. This fact is especially important in biomedicine and biometrics, allowing the geometric characterization of interior organs and pathologies with photogrammetric principles, as well as the automatic identification and labelling using computer vision algorithms.<br><br> This paper presents advances of close-range photogrammetry and computer vision applied to thermal infrared imagery, with the final application of Augmented Reality in order to widen its application in the biomedical field. In this case, the thermal infrared image of the arm is acquired and simultaneously projected on the arm, together with the identification label of the cephalic-vein. This way, blood analysts are assisted in finding the vein for blood extraction, especially in those cases where the identification by the human eye is a complex task. Vein recognition is performed based on the Gaussian temperature distribution in the area of the vein, while the calibration between projector and thermographic camera is developed through feature extraction and pattern recognition. The method is validated through its application to a set of volunteers, with different ages and genres, in such way that different conditions of body temperature and vein depth are covered for the applicability and reproducibility of the method.

scholarly journals Forest and land fire smoke detection using GCOM-C data (case study: Pulang Pisau, Central Kalimantan)

2021 ◽  
Vol 893 (1) ◽  
pp. 012068
Author(s):  
K I N Rahmi ◽  
N Febrianti ◽  
I Prasasti
Keyword(s):  
Near Infrared ◽  
Thermal Infrared ◽  
Short Wave ◽  
Forest Land ◽  
Visual Interpretation ◽  
Infrared Band ◽  
Central Kalimantan ◽  
Fire Smoke ◽  
Shortwave Infrared

Abstract Forest/land fire give bad impact of heavy smoke on peatland area in Indonesia. Forest/land fire smoke need to be identified the distribution periodically. New satellite of GCOM-C has been launched to monitor climate condition and have visible, near infrared and thermal infrared. This study has objective to identify fire smoke from GCOM-C data. GCOM-C data has wavelength range from 0.38 to 12 μm it covers visible, near infrared, short-wave infrared and thermal infrared. It is relatively similar to MODIS or Himawari-8 images which could identify forest/land fire smoke. The methodology is visual interpretation to detect forest/land fire smoke using near infrared band (VN08), shortwave infrared band (SW03), and thermal bands (T01 and T02). Hotspot data is overlaid with GCOM-C image to represent the location of fire events. Combination of composite RGB image has been applied to detect forest/land fire smoke. GCOM-C image of VN8 bands and combination of thermal band in composite image could be used to detect fire smoke in Pulang Pisau, Central Kalimantan.

scholarly journals Methane profiles from GOSAT thermal infrared spectra

2018 ◽  
Vol 11 (6) ◽  
pp. 3815-3828 ◽  
Author(s):  
Arno de Lange ◽  
Jochen Landgraf
Keyword(s):  
Lower Troposphere ◽  
Principal Component ◽  
Thermal Infrared ◽  
Total Carbon ◽  
Atmospheric Composition ◽  
Data Sets ◽  
Atmospheric Methane ◽  
Infrared Band ◽  
Correction Scheme ◽  
Infrared Measurements

Abstract. This paper discusses the retrieval of atmospheric methane profiles from the thermal infrared band of the Japanese Greenhouse Gases Observing Satellite (GOSAT) between 1210 and 1310 cm−1, using the RemoTeC analysis software. Approximately one degree of information on the vertical methane distribution is inferred from the measurements, with the main sensitivity at about 9 km altitude but little sensitivity to methane in the lower troposphere. For verification, we compare the GOSAT-TIR methane profile retrieval results with profiles from model fields provided by the Monitoring Atmospheric Composition and Climate (MACC) project, scaled to the total column measurements of the Total Carbon Column Observing Network (TCCON) at ground-based measurement sites. Without any radiometric corrections of GOSAT observations, differences between both data sets can be as large as 10 %. To mitigate these differences, we developed a correction scheme using a principal component analysis of spectral fit residuals and airborne observations of methane during the HIAPER pole-to-pole observations (HIPPO) campaign II and III. When the correction scheme is applied, the bias in the methane profile can be reduced to less than 2 % over the whole altitude range with respect to MACC model methane fields. Furthermore, we show that, with this correction, the retrievals result in smooth methane fields over land and ocean crossings and no differences can be discerned between daytime and nighttime measurements. Finally, a cloud filter is developed for the nighttime and ocean measurements. This filter is rooted in the GOSAT-TIR (thermal infrared) measurements and its performance, in terms of biases, is consistent with the cloud filter based on the GOSAT-SWIR (shortwave infrared) measurements. The TIR filter shows a higher acceptance rate of observations than the SWIR filter, at the cost of a higher uncertainty in the retrieved methane profiles.

Infrared Emission Spectra of Indium Phosphide at Elevated Temperatures

1997 ◽  
Vol 502 ◽  
Author(s):  
H. Rogne ◽  
P. J. Timans ◽  
H. Ahmed
Keyword(s):  
Elevated Temperatures ◽  
Semiconductor Device ◽  
Thermal Emission ◽  
Emission Spectra ◽  
Infrared Emission ◽  
Device Fabrication ◽  
Optical Measurements ◽  
Optical Data ◽  
Monitoring And Control ◽  
Process Monitoring And Control

ABSTRACTProcess monitoring and control during semiconductor device fabrication frequently relies on good knowledge of the optical properties of the substrate wafer and the surface coatings. However, these optical data are often unavailable, and as a consequence errors arise in pyrometric temperature measurements, as well as in thermal modelling of heating cycles. In this study, isothermal electron beam heating has been combined with in situ optical measurements to record thermal emission spectra of undoped InP specimens from 347 to 478°C, at wavelengths between I and 9 μm. The absorption coefficient was deduced from the emission spectra and reveals information about the temperature dependence of the infrared absorption mechanisms in InP.

scholarly journals Matter and Radiation in Superstrong Magnetic Fields and Thermal Emission from Neutron Stars

2003 ◽  
Vol 214 ◽  
pp. 181-190
Author(s):  
Dong Lai ◽  
Wynn C.G. Ho
Keyword(s):  
Radiative Transfer ◽  
Magnetic Fields ◽  
Neutron Stars ◽  
Thermal Emission ◽  
Surface Composition ◽  
Strong Field ◽  
The Novel ◽  
Radio Pulsars ◽  
Strong Magnetic Fields ◽  
Proper Interpretation

Thermal surface emissions have now been detected from more than a dozen isolated neutron stars, including radio pulsars, radio-quiet neutron stars and magnetars. These detections can potentially provide important information on the interior physics, magnetic fields, and surface composition neutron stars. Understanding the properties of matter and radiative transfer in strong magnetic fields is essential for the proper interpretation of the observations. We review current theoretical works on modeling magnetized neutron star atmospheres/surface layers, discussing some of the novel properties of matter and radiative transfer in strong magnetic fields. Of particular interest is the effect of the strong-field vacuum polarization, which dramatically changes the radiative transfer and the emergent X-ray spectra from magnetars.

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