Mapping and assessing limestone as a raw material for the cement industry using satellite data: a case study of areas between Riyadh and Al Kharj, Saudi Arabia

Satellite remote sensing is a popular method utilized in mineral and natural resource exploration, particularly to reduce reconnaissance and exploration costs. Its use is widely popular for geological mapping of arid regions. The primary objective of this paper is to illustrate how remote sensing satellite data could be used for mapping and assessing potential limestone raw material for the cement industry in Saudi Arabia. Limestone rocks are identified and mapped using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) indices, band combinations, band ratio combination, and relative absorption-band depth (RBD). Band combination of ASTER-thermal infrared (TIR) data 14:12:10, 8:6:1, and QI:CI:MI in R:G:B is also used for mapping limestone rocks with high efficiency as well as differentiating between sandstone and limestone rocks in the study area. Two band ratios 6/8 and 9/8 and RBD of (band 7+band 9)/band 8 are used for detecting limestone rocks as bright pixels. The carbonate index of ASTER-TIR data are subsequently used for mapping limestone areas and categorize them into classes for the purpose of using them as a raw material in the cement industry. Study findings show that high and very high classes of CI are concentrated in the southern and central parts of the study area such as Khashm Mazalij, Jabal Hit, and Jabal Hafafah and correlate with cement limestone and high-Ca limestone sites in the study area. Other very high limestone classes are found distributed in the northwestern part of Banban. Sulaiy Formation, in Khashm Mazalij area, also constitutes the best promising potential for high-purity limestone. It is hoped that the findings of the study provide ample evidence for the usefulness of the reconnaissance tool in assessing the limestone as raw materials, which is a vital process for the cement industry decision-makers in planning and managing natural resources in Saudi Arabia.