This study integrates continuous GPS observations from Indonesia's Ina-CORS network (2025—2026), earthquake catalogs (May 13—15, 2026), and geodetic time series to systematically track the progressive collapse process of the multi-level support points around the Java Plate. It focuses on the critical instability signals of the Molucca Sea arc-arc collision zone as the last rigid support, and verifies the authenticity and urgency of the support system collapse by combining recent shallow, intermediate, and deep-focus earthquake sequences. The results show that the Java Plate has entered a state of complete constraint loosening and semi-suspended sliding. The deep fulcrum (100–220 km) in the northeastern Molucca Sea exhibited threefold coupled anomalies in May 2026: abnormal accelerated GPS vertical subsidence (–6 to –22 mm/day), horizontal directional sliding (10–15 mm/day in the ENE direction), and clusters of intermediate-deep focus small earthquakes. Meanwhile, the dense earthquake sequence below 100 km in Java and adjacent sea areas from May 13 to 15 completely recorded the entire process of the support chain from loosening to collapse, marking the transition of the support structure from creep fracture to overall subsidence. This paper proposes a "plate support chain—fulcrum collapse—overturning and sliding" dynamic model, clarifying that the current period is a critical pre-earthquake window (1–3 days) for Mw 9.0+ great earthquakes, providing a verifiable paradigm for the physical prediction of great earthquakes in subduction zones.
Yu (Fri,) studied this question.