Technology and Methodology for Iron Ore Exploration
Iron ore exploration is the process of uncovering and investigating potential concentrations of iron ore in the Earths surface, which are important in the global production of steel and raw materials, thereby contributing to national fiscal receipts and promoting macroeconomic stability. Technological advancements and innovations in the industry have significantly improved the accuracy and efficiency of iron ore exploration. In this article, we discuss the technology and methodologies widely used in iron ore exploration.
Exploration is generally conducted using aerial survey techniques like Remote Sensing (RS), Global Positioning System (GPS) and Geographical Information System (GIS). RS helps in identifying surface hydrothermal and geologic expressions of some important iron ore bodies. It is classified as active or passive system. Active systems like ground-penetrating radar (GPR) and seismic imaging detect shallow sub-surface resistivity and seismic velocity contrasts. Other survey methods like LiDAR (Light Detection and Ranging) survey is popular for vegetation mapping for land surveys, structural mapping and terrain modeling.
GPS is widely used for navigation, surveying and mapping. It is mostly used for mineral exploration and hydrologic studies in order to get precise coordinates of the exploration sites. GIS is used to develop database and facilitate mapping related analysis. GIS analysis is done to generate accurate spatial databases with the help of satellite imagers and other spatial data. A digital elevation model (DEM) and digital terrain model (DTM) are additional databases used to create a 3D visual layer over the survey are using modern GIS.
Geochemistry sampling and laboratory analysis is conducted for exploration and quality evaluation. Geochemical sampling includes soil and rock sampling, which enables us to determine the nature and potential concentrations of ore deposit. The geochemical survey involves collection of samples and mapping of topography. Samples can be surface rock samples, chips, core, drilled samples, soil, water and vegetation. Laboratory analysis involves analysis of samples to identify trace elements such as copper, zinc, lead, and other chromium elements that are associated with ore deposits.
Geophysical surveys involve selections of static and mobilizing techniques. This helps us in identifying the potential ore bodies underlying potential surface and subsurface features. Gravity and magnetometer surveys are conducted to map and interpret subsurface layers and detect anomalies that are associated with ore bodies. Low frequency electromagnetic (EM) surveying is used for exploring shallow deposits, however, time domain EM surveys are used for deep targets.
Drill targeting and sampling is conducted in order to determine the grade and type of the orebody, which are planned based on the regional studies and depths of the target. Drilling methods include percussion (rotary) and diamond drilling. These techniques help in recovering core samples from depth, which are used for further geological or chemical analysis.
In conclusion, nowadays many different approaches are used for the exploration of iron ore, from surface surveys like remote sensing and LiDAR, to more precise techniques like gravity and electromagnetic surveys. Digital elevation models and digital terrain models are established through GIS, along with spatial databases. Sampling and laboratory analysis help in identifying potential ore bodies and finally, drill sampling is used to determine the grade and type of ore body. Technological advancements and innovations in the industry have enabled iron ore exploration to become more accurate and efficient.
