{
  "placement": {
    "type": "minecraft:random_spread",
    "salt": 0,
    "separation": 2,
    "spacing": 375
  },
  "structures": [
    {
      "structure": "minecraft:mineshaft",
      "weight": 1
    },
    {
      "structure": "minecraft:mineshaft_mesa",
      "weight": 1
    }
  ]
}