GeoTectonic

Vanilla's tangle of noodle caves is gone. In its place the underground is solid rock cut by seven hand-designed cave systems, each with its own shape, biome rules and reward for finding it.

Minecraft 1.21.1 on Fabric or NeoForge, and 1.20.1 on Fabric or Forge. Needs Architectury API.

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⭐ What It Does

• The deep is solid again - vanilla cave entrances, noodle caves, cheese voids, ravines and the extra underground carvers are all suppressed, so rock is rock except where GeoTectonic cuts it.
• Seven caves worth finding, each placed by biome and depth:
• Tectonic Fracture - a narrow surface crack that descends toward bedrock, widening and branching. Every overworld biome.
• Karst Chamber - warm biomes only. A vaulted hub with satellite rooms, stalactites, calcite veins and water on the floor.
• Cenote - warm biomes only. A narrowing shaft opens into a submerged chamber lit by glow berries, with a calcite rim at the waterline.
• Erosion Cave - a winding passage near sea level with a flowing channel, moss, hanging roots and clay.
• Sea Cave - an almost fully submerged passage carved from the seafloor or a coastal cliff.
• Crystal Vein - a straight gallery at deepslate depth on a mineral fault: heavy iron, gold, copper and redstone, a diamond and amethyst alcove at one end, a sealed cave-in at the other.
• Volcanic Vent - a hydrothermal chamber with a magma floor, basalt ceiling, rising chimney, central lava source and soul fire on the walls.
• Tune every one of them - each cave type has its own per-chunk spawn chance and an on or off switch.
• Know when you find one - an optional discovery subtitle, advancement and ambient loop the first time you enter each type in a session, each toggleable on its own.
• Four commands for finding and checking - /geotectonic find, list, stats and help, at operator level 4.
• It knows about Tectonic - a bundled worldgen override keeps the cave suppression from being reverted by Tectonic's own datapack, forced to top resource-pack priority whatever the load order.

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📋 Requirements

• Minecraft 1.21.1 on Fabric or NeoForge, and 1.20.1 on Fabric or Forge.
• Architectury API 13.0.8 or later on every loader.
• Fabric API, Fabric Loader 0.16.9 or later, and Cloth Config 15.0.140 or later, on Fabric.
• NeoForge 21.1 or later, on NeoForge.

📥 Installation

1. Install your loader and Architectury API, plus Fabric API and Cloth Config if you are on Fabric.
2. Install with the CurseForge app, or download the jar for your version and loader into your mods folder.
3. Create a world and dig down, or run /geotectonic find tectonic_fracture to be taken to the nearest one.

⚙️ Configuration

GeoTectonic writes config/geotectonic.toml on first launch. [cave_generation] holds a per-chunk spawn probability and an on or off switch for each of the seven cave types; [client] holds the three toggles for the discovery subtitle, the advancement and the ambient sound.

On NeoForge the file reloads with /reload. On Fabric it is polled every two seconds and reloads on its own. Either way a change applies only to chunks generated afterwards.

🖥️ Compatibility

• Existing worlds. Chunks generated before you added the mod keep their vanilla caves; only new chunks get GeoTectonic's. Expect a visible seam at the edge of explored terrain.
• Client or server. It changes world generation, so it goes on the server and on every client.
• The Nether changes too. Its vanilla carver is suppressed the same way, so Nether terrain loses its carved tunnels.
• Vanilla mineshafts, surface terrain, biomes, structures and ore distribution are untouched.
• Tectonic is handled by a bundled override. No override is bundled for any other terrain-generation mod on this branch, so another one that carves the overworld may conflict.

🐛 Support

• Leave a comment on this page.
• Include your Minecraft version, your loader and its version, the mod version, and your other mods.

📄 License

License terms are in the Alkeari License Agreement.