More than 150 aftershocks have been recorded after that New Jersey earthquake

Yet another aftershock, one of more than 150, was recorded Tuesday in the aftermath of the earthquake in central New Jersey that jolted the Philadelphia and New York areas last month, the U.S. Geological Survey reported.

The latest aftershock was classified as a magnitude 1.7, coming the day after a magnitude 1.9, the USGS said. Failing to rate above the 2.0 level, both were considered “microearthquakes.”

All of the aftershocks have rippled from the vicinity of the epicenter of 4.8 “main quake,” in the Tewksbury, Hunterdon County area, since the morning of April 5, the day the earth did not stay still beneath the Philly and New York regions.

Don’t be impressed by the quantity of aftershocks, advised Alexandra Hatem, USGS research geologist with the Geologic Hazards Science Center in Colorado.

“The aftershock sequence still remains normal,” she said.

Fewer than 10 of the aftershocks have exceeded the 2.0 threshold, according to USGS data, including a 2.6 last Wednesday, and a 2.9 on April 27. That 2.9 generated fewer than 1,000 reports of people having experienced the tremors, the agency said.

By contrast, the main quake on April 5 received over 180,000 reports, and more than 12,000 when a magnitude 3.7 was detected around 6 p.m.

What Hatem has seen since the main quake looks a whole lot like business as usual, she said.

“Aftershock sequences typically follow generally similar patterns,” she said, “and as far as I can see, this earthquake is no exception.”