Image of area around flow front

This map uses a satellite image acquired in March 2014 (provided by Digital Globe) as a base to show the area around the front of the June 27th lava flow. The area of the flow on November 24, 2014, at 12:00 PM is shown in pink, while widening and advancement of the flow as mapped on December 1 at 11:30 AM is shown in red.

Most surface flow activity is focused into a narrow finger that branches off the west edge of the flow field north of the East Rift Zone crack system. The front of this finger (19.475836, -154.986834 Decimal Degrees) was 4.6 km (2.9 mi) upslope from the intersection of Highway 130 and Pāhoa Village Road at the Pahoa Marketplace.

The dotted blue lines show the pertinent steepest-descent paths, calculated from a 1983 digital elevation model (DEM; for calculation details, see http://pubs.usgs.gov/of/2007/1264/), that the flow is projected to follow. Note that about 1 km (0.6 mi) downslope from the tip of the active flow two different steepest-descent paths come very close together. This is a location where the ground becomes very flat, and the flow could end up following either (or both) of these paths.

Steepest-descent path analysis is based on the assumption that the DEM perfectly represents the earth's surface. DEMs, however, are not perfect, so the dotted blue line can be used to infer only an approximate flow path.