Map data from landslides triggered by Hurricane Maria in the greater karst region of northwest Puerto Rico

Hurricane Maria caused widespread landsliding throughout Puerto Rico in September 2017. While the majority of landslide inventories following the hurricane focused on mountainous regions underlain by igneous and volcaniclastic bedrock (Bessette-Kirton et al., 2017, 2019), here we fill an important knowledge gap and document the occurrence of landslides along the greater karst region on the northwest side of the island. To examine the extent and characteristics of landslides in this area, we mapped individual landslides in municipalities including Aguadilla, Aguada, Arecibo, Barceloneta, Bayamon, Camuy, Ciales, Corozal, Dorado, Florida, Hatillo, Isabela, Lares, Manati, Moca, Morovis, Quebradillas, Rincon, San Sebastian, Toa Alta, Toa Baja, Utuado, Vega Alta, and Vega Baja. The boundary of our mapping was defined by the calcareous provence 62 (PROV 62) and nearby semi-calcareous sedimentary units (Bawiec, 1998). We used aerial imagery collected between 9-15 October 2017 (Quantum Spatial, Inc., 2017) to map landslide source and runout areas, and 1-m-resolution pre-event and post-event lidar (U.S. Geological Survey, 2018, 2020) as a digital base map for mapping. Difficulties with using these tools arose when aerial imagery was not correctly georeferenced to the lidar, when cloud cover was present in all images of an area, and in interpreting failure modes using only 2-dimensional aerial photos. These difficulties with aerial imagery were partially resolved using the lidar. The map data is comprised of headscarp points, travel distance lines, source area polygons, and affected area polygons that are provided as point, line, and polygon shapefiles that may be viewed using common geographic information systems. Various characteristics of the landslides and their geomorphic settings are included in attribute tables of the mapped features, and this information is described in the "Attribute Summary" document in the accompanying files. Quantitative attributes (e.g. failure travel distance, failure fall height, watershed contributing area, etc.) were determined using tools available with the ESRI ArcMap v. 10.6.1 geographic information system. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. References Bawiec, W.J., 1998, Geologic terranes of Puerto Rico, in Bawiec, W.J., ed., Geology, geochemistry, geophysics, mineral occur­rences and mineral resource assessment for the Commonwealth of Puerto Rico: U.S. Geological Survey Open-File Report 9-38, p. 59-71, accessed February 28, 2020, at https://pubs.usgs.gov/of/1998/of98-038/. Bessette-Kirton, E.K., Coe, J.A., Godt, J.W., Kean, J.W., Rengers, F.K., Schulz, W.H., Baum, R.L., Jones, E.S., and Staley, D.M., 2017, Map data showing concentration of landslides caused by Hurricane Maria in Puerto Rico: U.S. Geological Survey data release, https://doi.org/10.5066/F7JD4VRF. Bessette-Kirton, E.K., Cerovski-Darriau, C., Schulz, W.H., Coe, J.A., Kean, J.W., Godt, J.W., Thomas, M.A. and Hughes, K.S., 2019, Landslides triggered by Hurricane Maria: Assessment of an extreme event in Puerto Rico: GSA Today, v. 29, no. 6. Quantum Spatial, Inc., 2017, FEMA PR Imagery: https://s3amazonaws.com/fema-cap-imagery/Others/Maria (accessed October 2017). U.S. Geological Survey, 2018, USGS NED Original Product Resolution PR Puerto Rico 2015: http://nationalmap.gov/elevation.html (accessed October 2018). U.S. Geological Survey, 2020, USGS NED Original Product Resolution PR Puerto Rico 2015: http://nationalmap.gov/elevation.html (accessed October 2018).