Brownbag Talks

Unraveling the Source of Large Erratic Boulders on Tonga:
Implications for Geohazards and Mega-Tsunamis

Matt Hornbach
UTIG Research Associate, PH.D.

SEMINAR OVERIEW:
In November 2007, Cliff Frohlich, Fred Taylor, and Matt Hornbach traveled to Tonga in search of rumored reports of large out-of-place erratic boulders located along the western flank of Tongatapu. During their expedition, the researchers found a chain of massive coral boulders that had been deposit 100-400 m inland. Their preliminary analysis suggests these boulders may represent the largest known tsunami deposits on Earth (see attached photo).  Analysis of boulder sizes and locations combined with initial tsunami wave models indicates an unconventional wave-triggering mechanism. Come hear Matt Hornbach discuss their preliminary findings during this week's UTIG brownbag.