Six Earthquakes Shake Morris County in a Single Day — Residents Report Booms and Tremors Across Randolph and Mendham

On 22 July 2025, seismic activity occurred in Morris County, New Jersey for what seemed like an unusual reason, with locals from Randolph and Mendham describing everything from faint quakes and powerful thuds.

As stated by USGS, the shaking began in the early hours and persist to the USGS issued a report later in the evening, indicating the activity had subsided. The first earthquake, with a magnitude of 1.6 and a location slightly to the southeast of Randolph, occurred at around 5:40 a.m. The initial earthquake was followed by five aftershocks, one of which was stronger than the initial quake.

The largest aftershock of the day had a magnitude of 2.0 and was centered near the Mendham–Randolph border.

Full Timeline of Earthquakes in Morris County – July 21, 2025

Despite these tremors being lesser in magnitude, their frequency in this region caught the attention of a number of residents in the Garden State. As reported by USGS, dozens of residents indicated experiencing light to weak shaking.

Prior to this cluster, New Jersey experienced only two small quakes this year. These included a 2.4-magnitude tremor near Paramus, Bergen County. New York, New Jersey, and other adjacent states were shaken by a 4.8 magnitude earthquake in April 2024. Over 42 million individuals felt this earthquake and hundreds of aftershocks.

The quakes on Monday, although weaker, serve as a reminder of the inevitability of New Jersey quakes. Randolph and Mendham are now a part of an increasing list of state regions with sparse earthquake activity.

Although no injuries or infrastructure damage have been recorded, the region is being monitored for aftershocks. Report unexpected ground movement to the USGS Earthquake Hazards Program.