Northern Guam geospatial information server
Epikarst in northern Guam
Epikarst is the uppermost, heavily weathered and highly porous zone in a soil-covered or bare karst terrain. It has great hydrologic significance to catchment and transfer of rainwater to the subsurface. The epikarst comprises several meters of weathered and fractured bedrock containing dissolutionally enlarged fissures, pits, holes and other cavities, commonly filled with soil and sediment. The highlu porous epikarst allows water to rapidly percolate into the subsurface and then focuses that water to fast flow routes through the vadose zone. The fast flow routes are pipe-like conduits or widened fissures. These routes are dissolutionally enlarged over time by the water they conduct.