Geology and Resources of Basalt Quarry Site Kishb-13, Southern Harrat Kishb, Kingdom of Saudi Arabia
Hani H. Kurdi
Quarry site Kishb-13 on southern Harrat Kishb contains three cones of different shapes and sizes. The area measures 4.8 km north-south by 4.6 km east-west and was mapped at 1:5,000 scale. The area contains three extinct and eroded scoria cones assigned to the Quaternary lower Nafrat basalt referred to as the North, South, and East cones. The upper parts of the cones are composed of red agglutinated spatter and their craters are preserved. The main resource identified is vesicular basaltic scoria for very light to lightweight aggregate, suitable for use in the construction industry. Sixteen holes were auger-drilled (totaling 101.5m), to prove a resource estimated at 9 million m3, or 6.3 million tons. A number of laboratory tests were carried out on vesicular basalt samples obtained from both ground surface and drill holes. Thirty samples were tested for density by measuring 100 clasts for each sample. The total density ranges from 0.8 to 2.0. Grain size analyses were carried out on 29 samples of vesicular basaltic scoria. Most samples have a grain size from 32 mm to 1/16 mm. Thirty samples were subjected to 15-day tests for pozzolanic activity: 29 (97 percent) showed positive activity. Chemical analyses were carried out on 40 samples. The samples range from contaminated scoria to basalt lava with a silica range from 34.93 up to 49.04. Field investigations, drilling and laboratory results show that the most promising and highest quality resource in the area is concentrated in the East Cone, but the reserve is small.
Kurdi, H.H., 2003, Geology and resources of basalt quarry site Kishb-13, Southern Harrat Kishb, Kingdom of Saudi Arabia: Saudi Geological Survey Open-File Report SGS-OF-2002-4, 21 p., 13 figs., 8 tables, 2 apps., 1 plate.