Gadung quake began 607 km down; local effects remain unknown

The defining feature is how far underground it began—about 607 kilometres. That great depth generally means less surface shaking than an otherwise comparable shallow earthquake. It is a reason to distinguish this event from a near-surface quake of the same magnitude, not a basis for declaring that nobody felt it.⁠20⁠21

The earthquake occurred at 7:25:35 a.m. Philippine time on Sunday, November 8, 2026, according to the reviewed U.S. Geological Survey record. Its epicentre was listed at 6.706 degrees north latitude and 123.6541 degrees east longitude, 41 kilometres west-southwest of Gadung. The recorded magnitude type is mb.⁠28

Those two distances describe different things. The 41-kilometre offset locates the epicentre—the point on the surface directly above the earthquake’s underground source—relative to Gadung. The roughly 607-kilometre depth measures how far beneath the surface the earthquake began. The town-to-epicentre distance is not the distance from Gadung to that underground source.⁠28

In UTC, the earthquake happened at 23:25:35 on Saturday, November 7; the Philippines is eight hours ahead. The record’s latest listed update was at 7:41:08 a.m. Philippine time on November 8. Its “reviewed” status concerns the earthquake’s calculated parameters. It does not mean nearby communities have been checked for damage or injuries.⁠28

USGS classifies earthquakes originating between 300 and 700 kilometres below the surface as deep-focus events. At about 607 kilometres, this earthquake falls well within that range. Shaking diminishes with distance from the source, which is why depth is central to understanding the likely difference between this earthquake and a similar one much closer to the surface.⁠20⁠21

The agency illustrates the distinction by comparing an earthquake 500 kilometres deep with the same event at 20 kilometres: the deeper earthquake produces considerably less surface shaking. That is a qualitative comparison, not a calculation of shaking in Gadung. It supplies no event-specific intensity, numerical reduction or assessment of local consequences.⁠20

Magnitude and intensity also answer different questions. Magnitude describes the earthquake’s size; intensity describes the shaking experienced at a particular place. A single magnitude value cannot substitute for observations of what happened in individual communities. The listed depth helps explain what might be expected, but it cannot turn that expectation into a local measurement.⁠23

For this event, the USGS felt-report count, community intensity and instrumental intensity fields are all blank. These are missing values, not measured zeros. They therefore establish neither that the earthquake went unfelt nor that any particular level of shaking occurred. The record leaves the surface experience unresolved.⁠28

The catalog also lists no PAGER alert level. PAGER estimates population exposure to shaking and uses impact models to estimate fatalities and economic losses after significant earthquakes. A blank alert is not a green alert, and it supplies no finding of zero casualties or zero damage. There is no PAGER impact assessment to report from that field.⁠24⁠28

The tsunami field contains a zero. That catalog entry should not be recast as an event-specific Philippine tsunami advisory. No matching advisory was established in the available Philippine sources; an unrelated notice cannot answer the question for this earthquake. The distinction matters because a catalog field and an official advisory are not interchangeable.⁠28⁠12⁠13

A matching Philippine earthquake bulletin, event-specific felt intensities and local damage or injury findings were not established in the available material either. That is a limit on what can be reported—not confirmation that there were no effects. For now, the deep origin explains why less surface shaking would generally be expected; observations from nearby communities are still needed to establish what actually happened.⁠14⁠17⁠19