A burst of earthquake activity deep beneath the Pacific Ocean has caught the attention of scientists monitoring the Pacific Northwest—but officials say there’s no reason for concern on land.

According to the Pacific Northwest Seismic Network, a series of tremors began shortly after midnight on April 12 along the Juan de Fuca Ridge, a geologic feature located roughly 250 miles off the Washington coast. The area is known for frequent seismic activity due to shifting tectonic plates far beneath the ocean surface.

By midday, researchers had identified at least 18 separate earthquakes in the cluster, with the strongest reaching a magnitude of 4.2. While that may sound notable, quakes of this size and location are considered routine for this part of the ocean floor.

Importantly, scientists emphasized that this activity is happening far from the Cascadia Subduction Zone—the massive fault line capable of producing major earthquakes in the region. Data from the U.S. Geological Survey confirms the current swarm is not connected to that system.

The seismic network also clarified that the quakes are not occurring near Axial Seamount, an underwater volcano that has drawn attention in recent years due to signs it may eventually erupt. Despite speculation surrounding that site, this particular swarm is unrelated.

Experts say these offshore tremors are a normal part of the Earth’s ongoing tectonic movement and are not expected to have any impact on communities in Washington, Oregon, or the broader Pacific Northwest.

In short, while the ocean floor may be rumbling, life on land remains unaffected.