Field Observations of Ground Failure Triggered by the 2020 Puerto Rico Earthquake Sequence

This dataset consists of over 800 field observations of ground failure and other damage related to the 2019-2020 Puerto Rico earthquake sequence, and primarily triggered by the M6.4 mainshock on 7 January 2020. Observations were primarily collected from 12-18 January 2020, but data collection extended through the end of February 2020. Many observations are accompanied by text descriptions made during the field work by the observer. The location of the majority of the points represents the location of the observer/photographer because the coordinates come from geotagged photos and waypoints (unless otherwise noted).

Each observation is symbolized by ground failure type. Categories include:

·       Disrupted slides and falls: Landslides with high degrees of internal disruption, the majority of which were rock falls in this event, but some were rock slides or involved debris and soil.

·       Coherent slides:

·       Liquefaction: sand boils, fissures with ejecta, and other features that indicate liquefaction occurred but without obvious horizontal displacements.

·       Lateral spread: displacement on gentle slopes, commonly manifested as sets of extensional cracks parallel to a body of water. Though movement is commonly a result of liquefaction, we apply this category regardless of whether there was sand ejecta or other direct evidence of liquefaction.

·       Cracks: Ground cracks without any obvious ties to liquefaction or lateral spreading. Cracks are extensional except when otherwise noted.

·       Other: Ambiguous observations, such as crab burrows that were difficult to differentiate from sand boils, fallen trees, and other observations that do not fit in the other categories.

·       Damage: Building damage (not comprehensive) and damage to infrastructure such as water main damage and uplifted utility covers when not obviously related to liquefaction or lateral spreading.

·       Subsidence: observations are based on observations of flooding and are likely due to tectonic deformation.

For full details, refer to the USGS data release on ScienceBase.