# The rock cycle: how a mountain becomes marble

> A process map exported from forks.world (https://forks.world). Author: Brian. Source: https://forks.world/p/cmv0ie3lf001njw06h6axcs0i
> It describes who does what, in what order, and with which technology. Read the plain-language sections first; the JSON at the end is the exact, complete data.

## Summary

- 11 steps across 1 layer
- Technology / systems: Magma and lava, The rock, Heat, pressure and weather

## How to read this file

- A process is made of **layers**. The main layer is the top level; any step of kind `subprocess` opens a detail layer with its own lanes and steps.
- **Lanes** are either persona (people/roles) or technology (systems). Each step belongs to one lane; `using` lists tools a person uses for that step.
- Step kinds: `start`, `task`, `decision` (its arrows carry the answer as a label), `subprocess`, `end`.

## The rock cycle: how a mountain becomes marble

Lanes:
- Magma and lava: technology / system (id `magma`)
- The rock: technology / system (id `rock`)
- Heat, pressure and weather: technology / system (id `forces`)

Steps, in the order they run:

1. **Magma cools: slowly underground, fast at the surface** [start; Magma and lava; id `r1`]
   - then Igneous rock forms (granite, basalt)
2. **Igneous rock forms (granite, basalt)** [task; The rock; id `r2`]
   - then Weathering and erosion break it down
3. **Weathering and erosion break it down** [task; Heat, pressure and weather; id `r3`]
   - then Grains wash into rivers and seas
4. **Grains wash into rivers and seas** [task; The rock; id `r4`]
   - then Buried and squeezed for millions of years
5. **Buried and squeezed for millions of years** [task; Heat, pressure and weather; id `r5`]
   - then Sedimentary rock (sandstone, limestone)
6. **Sedimentary rock (sandstone, limestone)** [task; The rock; id `r6`]
   - then Buried deeper: heat and pressure rise
7. **Buried deeper: heat and pressure rise** [task; Heat, pressure and weather; id `r7`]
   - then Hot enough to melt?
8. **Hot enough to melt?** [decision; Heat, pressure and weather; id `r8`]
   - if "Yes" go to The rock melts into magma; if "No" go to Heat and pressure rewrite the minerals: marble, slate
9. **The rock melts into magma** [task; Magma and lava; id `r9`]
   - then Magma cools: slowly underground, fast at the surface
10. **Heat and pressure rewrite the minerals: marble, slate** [task; The rock; id `r10`]
   - then Pushed up by mountain-building, or buried deeper?
11. **Pushed up by mountain-building, or buried deeper?** [decision; Heat, pressure and weather; id `r11`]
   - if "Pushed up" go to Weathering and erosion break it down; if "Buried deeper" go to Hot enough to melt?

```mermaid
flowchart LR
  subgraph l_magma["Magma and lava"]
    n_r1(["Magma cools: slowly underground, fast at the surface"])
    n_r9["The rock melts into magma"]
  end
  subgraph l_rock["The rock"]
    n_r2["Igneous rock forms (granite, basalt)"]
    n_r4["Grains wash into rivers and seas"]
    n_r6["Sedimentary rock (sandstone, limestone)"]
    n_r10["Heat and pressure rewrite the minerals: marble, slate"]
  end
  subgraph l_forces["Heat, pressure and weather"]
    n_r3["Weathering and erosion break it down"]
    n_r5["Buried and squeezed for millions of years"]
    n_r7["Buried deeper: heat and pressure rise"]
    n_r8{"Hot enough to melt?"}
    n_r11{"Pushed up by mountain-building, or buried deeper?"}
  end
  n_r1 --> n_r2
  n_r2 --> n_r3
  n_r3 --> n_r4
  n_r4 --> n_r5
  n_r5 --> n_r6
  n_r6 --> n_r7
  n_r7 --> n_r8
  n_r8 -->|"Yes"| n_r9
  n_r8 -->|"No"| n_r10
  n_r10 --> n_r11
  n_r11 -->|"Pushed up"| n_r3
  n_r11 -->|"Buried deeper"| n_r8
  n_r9 --> n_r1
```

## Full data (JSON)

```json
{
  "title": "The rock cycle: how a mountain becomes marble",
  "maps": {
    "m_root": {
      "id": "m_root",
      "lanes": [
        {
          "id": "magma",
          "name": "Magma and lava",
          "type": "system"
        },
        {
          "id": "rock",
          "name": "The rock",
          "type": "system"
        },
        {
          "id": "forces",
          "name": "Heat, pressure and weather",
          "type": "system"
        }
      ],
      "steps": [
        {
          "id": "r1",
          "kind": "start",
          "lane": "magma",
          "next": [
            {
              "to": "r2"
            }
          ],
          "uses": [],
          "label": "Magma cools: slowly underground, fast at the surface"
        },
        {
          "id": "r2",
          "kind": "task",
          "lane": "rock",
          "next": [
            {
              "to": "r3"
            }
          ],
          "uses": [],
          "label": "Igneous rock forms (granite, basalt)"
        },
        {
          "id": "r3",
          "kind": "task",
          "lane": "forces",
          "next": [
            {
              "to": "r4"
            }
          ],
          "uses": [],
          "label": "Weathering and erosion break it down"
        },
        {
          "id": "r4",
          "kind": "task",
          "lane": "rock",
          "next": [
            {
              "to": "r5"
            }
          ],
          "uses": [],
          "label": "Grains wash into rivers and seas"
        },
        {
          "id": "r5",
          "kind": "task",
          "lane": "forces",
          "next": [
            {
              "to": "r6"
            }
          ],
          "uses": [],
          "label": "Buried and squeezed for millions of years"
        },
        {
          "id": "r6",
          "kind": "task",
          "lane": "rock",
          "next": [
            {
              "to": "r7"
            }
          ],
          "uses": [],
          "label": "Sedimentary rock (sandstone, limestone)"
        },
        {
          "id": "r7",
          "kind": "task",
          "lane": "forces",
          "next": [
            {
              "to": "r8"
            }
          ],
          "uses": [],
          "label": "Buried deeper: heat and pressure rise"
        },
        {
          "id": "r8",
          "kind": "decision",
          "lane": "forces",
          "next": [
            {
              "to": "r9",
              "label": "Yes"
            },
            {
              "to": "r10",
              "label": "No"
            }
          ],
          "uses": [],
          "label": "Hot enough to melt?"
        },
        {
          "id": "r10",
          "kind": "task",
          "lane": "rock",
          "next": [
            {
              "to": "r11"
            }
          ],
          "uses": [],
          "label": "Heat and pressure rewrite the minerals: marble, slate"
        },
        {
          "id": "r11",
          "kind": "decision",
          "lane": "forces",
          "next": [
            {
              "to": "r3",
              "label": "Pushed up"
            },
            {
              "to": "r8",
              "label": "Buried deeper"
            }
          ],
          "uses": [],
          "label": "Pushed up by mountain-building, or buried deeper?"
        },
        {
          "id": "r9",
          "kind": "task",
          "lane": "magma",
          "next": [
            {
              "to": "r1"
            }
          ],
          "uses": [],
          "label": "The rock melts into magma"
        }
      ],
      "title": "The rock cycle: how a mountain becomes marble",
      "parent": null
    }
  }
}
```