Drill core scanning at SGU
During 2014, SGU started a project to scan 200 000 meters of drill core at SGUs drill core archive in Malå. The drill cores to be scanned are from Norrbotten and Västerbotten in northern Sweden. Included in the assignment is high resolution optical photography as well as hyper spectral infrared imaging.
The new database with optical and infrared drill core imagery will serve as a compliment to the physical drill cores that are stored in Malå. The data can be used by exploration companies as well as researchers and will contribute to a sustainable use of Sweden’s mineral resources. The results will be published trough the SGU map viewer “Drill Cores” and data can be ordered from the customer service.
Hyper spectral Infrared Core Imaging
Hyper spectral imaging is a passive, non-destructive technique that only requires illumination of the sample for measurement. During scanning, the drill cores are illuminated and special cameras in the scanner measure how visible and infrared light across different wavelength ranges is reflected from the surface of the drill core. Because minerals have characteristic signatures across different regions of the infrared spectrum, the collected data can provide information about the mineralogy of the drill core. The scanning will capture visible and near-infrared (VNIR), short-wavelength infrared (SWIR) and long-wavelength (LWIR) spectral images as well as a high-resolution optical RGB image, all in a single scan, directly in the drill core box.
The data includes raw data, processed data, optical images and two types of False Color Composites. The information can be used by mining and exploration companies, researchers, consultants and others, either for direct use or for further processing and calibration against spectra of known minerals.
Optical image of the drill core in the box, picture taken in visible light. Photo: SGU
A False Color Composite (FCC) image of the drill core from the same box as above. The image is complied by data from the short wave length of the infrared spectrum. Three infrared bands compose the RGB-picture. The three wave lengths used are red=1749 nm, green=1649 nm and blue=1419nm. Photo: SGU
A False Color Composite (FCC) image of the drill core from the same box as above. The image is complied by data from the long wave length of the infrared spectrum. Three infrared bands compose the RGB-picture. The three wave lengths used are red=8611 nm, green=10022 nm and blue=11810 nm. Photo: SGU
How to order data
To access the drill core data, open the SGU Map viewer Drill cores. To obtain information about the scanned drill core you click on the symbol to open a popup window with the metadata about the selected drill core. By clicking the link “Scanned drill core” you will open an online tool where you can view and interrogate the data and images from the selected core. The images are from visible and near-infrared VNIR, short-wavelength infrared SWIR and long-wavelength LWIR spectral images as well as a high-resolution optical RGB images. Data is ordered per drill core. The ID number for the drill core is visible when you open the information window for each drill core. Also choose if you want raw data (level 0), processed data (level 2) or both. Data volume for one drill core box (cirka 10 m core) is approximately 1,5 gigabyte (GB). Data is delivered on USB disks of 2 terabyte (TB) capacity. The data itself if free of charge, but we charge a delivery fee of 1200 SEK plus 1000 SEK for each USB data disk.
The data is licensed under Creative Commons Attribution 2.5 Generic (CC BY 2.5). That means you are free to share, copy and redistribute the material in any medium or format and adapt (remix, transform, and build) upon the material for any purpose, even commercially as long as you give attribution to the Geological Survey of Sweden.
Different processing levels
As a standard partly processed data is delivered (level 2 data). Level 2 represents a processing level where the data has undergone instrument and project specific system corrections, the data has been reflectance corrected and has been prepared for further spectral processing and product generation. Level 2 data also includes False color composite (FCC) images. Raw data (level 0 data) has not been processed i.e. no data correction, normalization or band subsetting has been performed on this data. As of today, level 0 data is available from 160 drill cores. Level 2 data is available from a subset of 155 of these. More data will be released as the project continues. Full processing (level 5) that includes mineral identification will be performed on 10 000 meters of drill core. The level 5 data will be released at a later stage.
The online tool for viewing scanned drill cores is currently having problems with the latest versions of Google Chrome (version 45 and later). Please use another browser (e.g. Internet Explorer).