HARRISON — Earthquakes in northern Arkansas are being linked to the weight of extra water at a flood-swollen reservoir.
Earthquake geologist David Johnston works with the Arkansas Geological Survey. He said the added weight of the water at Bulls Shoals Lake likely triggered 10 earthquakes over five days last week near Harrison, a city about 140 miles north of Little Rock.
Johnston said the reservoir's water level has risen 42 feet because of rainfall since March 1.
Johnston told the Springfield News-Leader the quakes are small, ranging from 1.5 to 3.6 in magnitude, and aren't expected to end soon.
Johnston said there weren't immediate reports of damage after a 3.6-magnitude quake June 11. But he said some people reported houses creaking and pictures rattling on walls.
The Arkansas Geological Survey will add more ground-detection devices to better record the earthquakes, Arkansas Online previously reported.