🔍 Objectives
- Resolve trough ↔ counterweight pairings at corridor, basin, and global scales.
- Estimate symmetry (S), time lag (τ), and coupling strength (κ) for each pair.
- Produce a Balance Score used to modulate forecast intensity in V9.7.
🧠 Key Concepts
- Mass/torque complementarity: lithospheric deficits balanced by distant surpluses.
- Hemispheric seesaws: N↔S handoffs tracked by cap dominance (from dataset).
- Memory repair: symmetry recovers following cryosphere pulses & rebound.
📦 Data Inputs
- Geoid/gravity anomalies (Bouguer, satellite), heat-flow, topography/bathymetry, crustal thickness.
- Seismicity & focal mechanisms, GNSS strain, GIA fields, uplift/subsidence time series.
- V9 dataset fields: epoch/cycle, cap dominance, rift (−), counterweight (+), meltwater vectors, VGP ties.
- V3 geodesic mesh & corridors; V9.4 ranked node set.
🧪 Methods
- Pairing: for each trough center, search great-circle corridors for candidate uplifts (within angular windows); minimize cost by distance, corridor alignment, and anomaly sign.
- Signal normalization: z-score geoid/heat-flow/topo and construct composite
A−/A+indices. - Symmetry index (S):
S = 1 − |A− − A+| / (|A−| + |A+| + ε)(0=asymmetric, 1=balanced) - Lag (τ): time of peak cross-correlation between paired anomaly time series (positive = counterweight follows).
- Coupling (κ): coherence of derivatives (dA/dt) with sign-corrected phase agreement (0–1).
- Balance score:
B = wS·S + wK·κ − wT·|τ|/τref(clipped to 0–1). - Bootstrap & CV: resample epochs and corridors to estimate uncertainty σB.
🧮 Practical Defaults
- Angular search window: 40° along-corrridor / 25° cross-corridor; great-circle sampling Δ=0.25°.
- τ window: ±200 kyr (late Cenozoic); ±5–10 Myr for Mesozoic deep-time panels.
- Weights:
wS=0.5,wK=0.35,wT=0.15,τrefset by epoch bin.
🗺️ Figures
- Chord map: troughs (−) ↔ counterweights (+) with link opacity ∝ B.
- Lag histograms per epoch; hemisphere seesaw timelines with cap dominance overlay.
- Corridor panels showing paired anomaly time series and cross-correlograms.
✅ Outputs
- pairs.csv —
id_minus,id_plus,epoch,S,kappa,lag_kyr,B,sigma_B,corridor,hemisphere - pairs.geojson — FeatureCollection with great-circle links and node properties.
- balance_summary.json — per-corridor & global stats for V9.7 throttling.
🧰 Minimal Schema (pairs.csv)
id_minus,id_plus,epoch_kya,S,kappa,lag_kyr,B,sigma_B,corridor,notes
AMZ_TRGH_01,AND_UPLF_02,120,0.76,0.62,18,0.69,0.08,72.66W,"seesaw N→S; strong meltwater vector"
🔧 QA & Sensitivity
- Shuffle controls: randomize pairings within corridors → expect S, κ to collapse toward 0.
- Leave-one-sensor-out (geoid/heat-flow/topo) to test metric robustness.
- Weight sweep (
wS,wK,wT) to bracket B; report σB and stable ranges.
🔗 Integration
- V9.4: multiply each node’s Multiplier by the local B (or corridor mean B).
- V9.7: catastrophe windows prioritize nodes in low-B regions (unstable symmetry) during aligned forcing.
- V9.8: export pair classes (e.g., rift–orogen, back-arc–superswell) for analogue-planet testing.
📚 References (to stage)
- Global gravity/geoid & heat-flow datasets; GIA/uplift models; plate boundary & crustal thickness grids.