# C1592 — Derive the SP inverse Flood–MT Shem junction

## Question

Why does the completed SP inverse Flood land at the ordinary Rounded MT Cumulative Shem boundary?

## Sources

```json
[
  "lower_decimal_mechanism.json",
  "File51a §16.2",
  "Comparative_Study §7.5"
]
```

## Opened utc

2026-09-29T14:54:39.433321+00:00

## Results

```json
{
  "held_Floods": {
    "MT": 4836,
    "LXX": 5746,
    "SP": 2736
  },
  "completed_Floods": {
    "MT": 7536,
    "LXX": 8446,
    "SP": 5436
  },
  "ordinary_MT_Shem": 5436,
  "identity": "2700 - (120 + 1980) = 600",
  "independent_inputs": [
    "source MT–SP120",
    "SP reversal contraction1980",
    "anchor stage2700",
    "Shem life600"
  ]
}
```

## Finding

The source and operation supply2700−2100=600. Consequently the completed SP inverse Flood lies exactly one Shem lifespan earlier than the held MT Flood, at5436.

## Reassessment

This is the informative cross-family condition; test whether the MT–LXX910 transport survives changing the named cut.

## Checks

```json
{}
```

## Closed utc

2026-09-29T14:54:39.433750+00:00

## Record provenance

Exact record hash: `3aec6b45730d7f7c870b3a7ce17840968580056ef227312b753552af1cbd2b75`

Source journal: `Research_Cycles/C1585_C1634/journal.json`