Fig. 3

Visual comparison of an example parent map and simplified map graphic. a This figure displays a section of the Mount Hood parent hazard map. The published dimension is 0.83 m by 1.4 m. Advantages for use of the Mount Hood parent map are inclusion of critical distinctions between two proximal zones that correspond to a region of higher threat-probability (area in close proximity to the vent is shown in pink), and a lower-probability zone that is less accessible to the vent (shown in yellow); estimations of lahar travel times; thorough description of volcanic processes and related probabilities; and inclusion of hydrologic and hypsometric features. b This figure displays the Mount Hood simplified map with an explanation similar to that developed for the National Park Service exhibit. The simplified hazard map is commonly printed at scale of 0.28 m by 0.36 m. Its Near-volcano hazard zone includes lava flows, pyroclastic flows, thick tephra fall, rock avalanches and rockfall. Relative potential of lahar inundation is indicated as gradient from red to yellow. Tan designates areas subject to lava flows issuing from dispersed vents. Dark gray in valleys near top of map display lahar hazards from other volcanoes that intrude into the space of this map. Advantages of the simplified map include the exclusion of non-essential information including topographic contours and minor hydrographic features, a small format that allows viewers to gain a general sense of the area quickly, ease of viewing of hazard zones information and landmarks, and ease of placement within documents