# 📐  L2 Spec — Poroelasticity — Biot coupled solid/fluid Mismatch-Only Spec

**ID:** `L2-227-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-227`](/artifact/l1/L1-227)

> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.48 · **Delta tier:** 5
> **⛓ On-chain block:** 41554025

---

## 1. Domain Ω

**Type:** `range`

| Parameter | Unit | Range |
|---|---|---|
| N dof | — | 100 – 1000000 |
| Snr db | dB | 0 – 40 |
| E error | — | 0.0 – 0.1 |
| M error | — | 0.0 – 0.1 |
| N times | — | 10 – 100000 |
| Biot alpha error | — | 0.0 – 0.1 |
| Permeability error | — | 0.0 – 0.3 |

## 2. Tolerance (ε)

**Type:** `fn`

```
16.0 + 0.3*SNR_dB - 10.0*permeability_error - 30.0*biot_alpha_error - 20.0*M_error - 20.0*E_error
```

## 3. Difficulty

| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |

## 4. Fingerprint

`c1dc939d4723595d8ed221c12adb19dcbfe460455dfbb36895f86b745fbaf75c`

## 5. On-chain Registration

- **Chain hash:** `0x46ccd3df3a7fd7960024df1e7bfd27d0e8d75f09efa535e8084e04399f32ce56`
- **Chain tx hash:** `0x494b0cfb833fa6f6cdef12b45bf4eb2e9bc3dadbd146412cef381662e61ef497`
- **Chain block:** `41554025`

---

## File Mapping

This bundle consists of: `L2-227-001.md`, `L2-227-001.json`.

| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-227-001.md` | Source of truth — edit this | Human or LLM |
| `L2-227-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |

**Prompt for your LLM after editing this Markdown:**

> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.

_This Markdown was auto-synthesized from the catalog row for `L2-227-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._