We've added a new segment to the mining applications section of our website called Minerals Analysis. In this section we will add content that highlights minerals that have spectrally active features in the near infrared (NIR), making them ideally suited for the rapid, precise minerals analysis of the TerraSpec 4 mineral analzyer.
The NIR Community from ASD Inc., a PANalytical company
New to using NIR for mining exploration or want a refresher course?
The expert training staff at Spectral International, Inc., an ASD distributor focused on mining exploration, will hold an applied field spectrometry course September 12-16 in Arvada, Colorado.
The course covers basic spectroscopy for field applications. The emphasis will be on minerals, their associations, applications and spectral interpretation. This hands-on class provides a great opportunity to use and experiment with the TerraSpec Explorer spectrometer in a live environment.
ASD, Inc. announced this week the launch of two solutions aimed at solving measurement and process challenges for mining and ore properties. Utilizing spectroscopic technology, the TerraSpec Explorer and TerraSpec Examiner analyzers can be used for analysis of minerals in mining exploration and mining production. These solutions provide precise real-time data for an entirely new level of visibility into every stage of mining – anywhere the sample resides.
ASD's instrumentation is widely used in remote sensing research. Last year, ASD's instrumentation was cited in over 450 peer reviewed papers. Each month, I will focus on a few specific application areas, highlighting several published papers and reports that utilize measurements made using ASD's instrumentation. This month, I've focused on the areas of soils research and mineral exploration.
I would like to discuss mineral deposits we have in the Great Basin and how we study them, including remote sensing, Great Basin study sites, mineralogy and methods for studying deposits.
The Great Basin of the Western United States has a thin continental crust and geologic structures. Stretching across parts of Nevada, Utah, Oregon, Idaho and California, the Great Basin has high geothermal activity, lots of rifting, faults and fluid flow, which all created great mineral deposits. Geothermal systems are associated with thin crusts and extension events. Heat, flow, porosity and fluids mean lots of mineral deposition. The Great Basin has been called the Saudi Arabia of geothermal activity.
We study the strain in Great Basin faults. The area is composed of volcanic edifices, low and high sulfidation systems, and includes flows of gold, copper and porphyry. We use spectroscopy to identify the many minerals present in this area.
Phases of minerals and zones in high sulfidation areas are common geologic features in the Great Basin. We can map the minerals and find where you are in the zone and how erosion has exposed the minerals. Work at Virginia City, Nevada uncovered major silver ore deposits within vertical faults that dip into the ground. The structure of the ore-bearing zone features particular mineral patterns at different levels and distances to the faults. We looked at "Group Shoot" AVIRIS data to detect mineral assemblages, then field-checked the classification. We didn't have an ASD instrument at the time, but used X-rays to verify that the classification was correct.
In 1999, we bought our first ASD spectrometer, which is now a "classic." We took SpecTIR airborne data (2m pixels) and used ENVI to identify minerals. Then we cross-compared this data to AVIRIS data (18m pixels) and did sub-pixel analyses, using the ASD classic instrument to field check.
Other Mineral systems, such as low sulfidation systems contain mineral assemblages with disseminated ore at depth. We went to Cuprite, Nevada to map these kinds of mineral alterations using AVIRIS data. We sampled the minerals with an ASD FieldSpec Pro spectrometer [now a FieldSpec 3] and flew a ProSpecTIR in a Cessna to further map the site.
The development of the ASD series of portable spectrometers was a breakthrough that enabled one person to collect the necessary ground spectral data that was important for image processing and analysis of hyperspectral image data.