Density map of hydrate evidence (samples of hydrates in gravity cores or wells) and indicators (seismic anomalies or geochemical indicators). It has been developed with the “point density” algorithm of ArcGIS®. Pixel value, number of data per 100,000 km2. Parameters: population field, none; cell size, 5000; radius, 178,415 metres; areal units, square kilometres; method, geodesic. Knowledge gap, raster value < 1 Reference: https://doi.org/10.3390/app11062865

Density map of geothermal gradient developed with the “point density” algorithm of ArcGIS®. Pixel value, number of data per 100,000 km2. Parameters: population field, none; cell size, 5000; radius, 178,415 metres; areal units, square kilometres; method, geodesic. Knowledge gap, raster value < 1 Reference: https://doi.org/10.3390/app11062865

Density map of seafloor temperature developed with the “point density” algorithm of ArcGIS®. Pixel value, number of data per 100,000 km2. Parameters: population field, none; cell size, 5000; radius, 178,415 metres; areal units, square kilometres; method, geodesic. Knowledge gap, raster value < 1 Reference: https://doi.org/10.3390/app11062865