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Database for the Geologic Map of the Northern Harrat Rahat Volcanic Field, Kingdom of Saudi Arabia

December 23, 2019

The Harrat Rahat volcanic field, located in the west-central part of the Kingdom of Saudi Arabia, is the largest of 15 harrats (Arabic for 'volcanic field') hosted within the Arabian plate. Harrat Rahat is 50 to 75 km wide (east-west) and 300 km long (north-south), covering an area of approximately 20,000 square kilometers and encompassing more than 900 observable vents. The overall map area and its dataset show the volcanic geology of the northern part (about 3,340 square kilometers) of Harrat Rahat, at a scale of 1:75,000. Two additional map areas and their feature classes highlight areas of interest at 1:25,000 scale. Northern Harrat Rahat is of interest owing to the location of the city of Al-Madinah Al-Munawarah (hereafter, referred to as Al-Madinah), which sits atop (and is recently expanding over) the north end of the volcanic field. Al-Madinah is home to more than 1.5 million residents, and the city experiences an additional influx of approximately 3 million pilgrims annually. The downtown area of Al-Madinah is less than 8 km from lava flows of the only confirmed historical eruption (unit bla; eruptive stage 1), which occurred in 1256 C.E.

This geologic map database is accompanied by a report, which includes the formatted geologic map and explanatory pamphlet, available at https://doi.org/10.3133/sim3428.

The authors ask that users of the geologic map database cite both the database and the report:

Report: Downs, D.T., Robinson, J.E., Stelten, M.E., Champion, D.E., Dietterich, H.R., Sisson, T.W., Zahran, H., Hassan, K., and Shawali, J., 2019, Geologic map of the northern Harrat Rahat volcanic field, Kingdom of Saudi Arabia: U.S. Geological Survey Scientific Investigations Map 3428 [also released as Saudi Geological Survey Special Report SGS-SP-2019-2], 65 p., 4 sheets, scales 1:75,000, 1:25,000, https://doi.org/10.3133/sim3428.

Database: Robinson, J.E., Downs, D.T., Stelten, M.E., Champion, D.E., Dietterich, H.R., Sisson, T.W., Zahran, H., Hassan, K., and Shawali, J., 20XX, Database for the geologic map of the northern Harrat Rahat volcanic field, Kingdom of Saudi Arabia: U.S. Geological Survey data release, https://doi.org/10.5066/P9Q3WGTN