The biggest earthquake, with a magnitude of 4.2, briefly startled lawmakers in session in the Nevada capital. There were no immediate reports of damage, but seismologists are concerned about a recent series of quakes near the lake and the potential for a tsunami.
At least six earthquakes, including one with a preliminary magnitude of 4.2, shook the Lake Tahoe, Reno and Carson City area early on Friday, according to the U.S. Geological Survey.
The strongest one struck near the north end of the lake at Dollar Point, Calif., around 8:30 a.m. Pacific Daylight Time. There were no immediate reports of damage.
It came as Lake Tahoe’s resorts and tourist destinations prepared for a Memorial Day holiday that they hope will help lift the pall of the coronavirus pandemic and as legislators in Nevada’s capital met in early sessions to finish business before heading home for a long weekend.
The strongest quake on Friday interrupted Senator Julia Ratti’s presentation before an Assembly Committee on Ways and Means hearing.
The geological survey initially reported that the quake had a preliminary magnitude of 4.1, but that was revised higher. It followed an earlier one with a preliminary magnitude of 2.9, around 5 a.m. local time in the Dollar Point area, according to the U.S.G.S.
Later Friday morning, four more smaller earthquakes were reported, with preliminary magnitudes ranging from 2.7 to 3.1, according to the geological survey.
Dr. Graham M. Kent, the lab’s director, said there had been “many dozens” of earthquakes since then of magnitudes between 1 and 3.
He said such sequences were being closely watched by seismologists because if the current sequence continued, it could trigger one of the two main fault lines beneath the lake, and that in turn could set off a tsunami wave as high as 30 feet.
Alex Hatem, a U.S.G.S. research geologist, said the 4.2 earthquake this morning occurred in a faulting area known as the Walker Lane that had “complex and closely spaced faults of different styles,” which made it difficult to determine which fault ruptured on Friday.