The slab is real. The corridor is honest. The cause is still a question.

An interactive reading of the Sarangani–Cotabato aftershock field against independently modeled subduction geometry — built to keep the hypothesis disciplined, not to make it louder.

900 PHIVOLCS-derived rows Slab2 independent geometry v0.1 exploratory gate No prediction claim
02 · Field

Slab-aware aftershock field

Most aftershocks sit inside or near the Cotabato Slab2 region, but their depths do not form a simple slab-interface-only story.

Observed catalog Modeled Slab2 Inferred corridor Not prediction
north–south corridor
modeled slab depth
★ mainshock reference
event particle
near slab top
Slab2 contour
PCA axis
events total900PHIVOLCS-derived public-page scaffold
valid slab2 match815nearest modeled slab node found
median node distance3.14 kmstrong spatial coverage context
median depth delta−28.8 kmevents mostly above slab top
03 · Reading

The slab matters, but it does not explain everything.

The sequence is clearly inside the active Cotabato subduction environment, which makes ordinary tectonic coupling the first explanation to respect. But most hypocenters are shallower than the modeled slab top, and the corridor does not simply trace Slab2 strike or contour lines.

above slab top
64.62%
near slab top
32.56%
below slab top
2.83%
04 · Claim ledger

What is observed, what is modeled, what remains.

The gate exists to keep these categories from bleeding into each other.

observed

PHIVOLCS-derived events form a structured aftershock field around Sarangani / Cotabato.

modeled

USGS Slab2 places those events inside or near the Cotabato slab geometry region, with dense nearest-node coverage.

inferred

The aftershock corridor is nearly north–south at about 179.4°, but local Slab2 strike differs by a median 34.7°.

remaining

TMCH survives only as a residual hypothesis: test bathymetric, gravity, magnetic, ridge, seamount, or buried-lineament structures after active slab and fault mechanics are accounted for.

05 · How to read the gate
01 / scaffoldStart with events.

Each dot is an earthquake in the PHIVOLCS-derived working scaffold, not an official aftershock-association export.

02 / slabAdd independent geometry.

Slab2 contributes modeled slab depth, strike, dip, uncertainty, and contours — an outside witness the visual pattern cannot argue with.

03 / depthCompare vertical position.

Most events sit above the modeled slab top, so the simple interface-only interpretation weakens.

04 / corridorTest the visible line.

The measured corridor does not simply match slab strike or depth-contour direction. The line is real-looking; it is not self-explaining.

05 / residualOnly then ask TMCH.

If inherited structure exists, it should appear as residual alignment beyond Slab2, active faults, and catalog artifacts.

Source report: TMCH Slab2 Alignment v0.1 — USGS ScienceBase Slab2 Cotabato data release, Hayes 2018, DOI 10.5066/F7PV6JNV; PHIVOLCS-derived 900-row public latest-earthquake scaffold. This page visualizes the report’s interpretation; it does not add new scientific evidence.