Hawaiian Volcano Observatory recently put out a preliminary lava thickness map, based on last summer’s Kilauea lava flow. They’ve created similar maps before, but mostly for official publications. Now this map is on the HVO web site.

Hawaiian Volcano Observatory geologist Frank Trusdell says the public, government officials, and scientists are eager to get more data about last summer’s lava flow. That led to the decision to put the preliminary lava thickness map online — with some context.

“We’re comparing the thickness of the current flows to the topography before the flows. Down by the coast where the topography is relatively flat the flows have thickened and overplated several times over, and that’s where the greatest thickness is. Where the slopes are steeper, lava will drain away just like liquid will drain away from highs and pond in lows.”

The map shows the thickest lava on land is around 180 feet. In the ocean, just offshore of Kapoho, the lava is estimated at more than 900 feet thick. Trusdell explains why:

“The water will more quickly congeal the lava and so it won’t flow away or drain and then additional flows will just stack up.”

He says scientists have a myriad of uses for the data, and it will also help with restoration in lower Puna.

“You would have an estimate of how thick the flows are for pushing in brand new roads.”

HVO compiled data from thousands of photographs gathered by drones that flew over the lava flow. Trusdell says to get the more comprehensive data they need, they will use a plane with LIDAR, or light imaging, to survey the entire 2018 lava flow.

Hawaiian Volcano Observatory had scheduled the LIDAR mapping plane for January, but the government shutdown meant the mission had to be postponed. HVO is now awaiting a new date.