I've been playing around with a couple of settings in world gen - trying to create a region with a decent number of volcanoes and nice, open caverns. I've only really edited:
Cavern openness
Cavern density
Volcano number
Mineral scarcity (nothing too drastic)
I've got exactly the sort of caverns I want... except they're barren. Sometimes I'll get 2 good, vibrant, living caverns and one containing nothing but mud and bloodthorns, sometimes I'll have barren caverns at all levels.
I have searched for similar threads and noted other people had a similar issue. However, in those threads people mentioned that a cavern without natural water would be barren, and this happened to me even in caverns with plenty of pools of water about the place. I also tried running the areas for a while after breaching between the caverns to see if spores spread, but they did not, even when the barren area had plenty of pools of water/
In any case, I tried the suggested fix of increasing the minimum water amount above 0, and I'm still having the same issue. I've genned maybe a dozen worlds over the last two days, and no matter what I do, tweaking cavern density and openness just seems to gen sometimes entire worlds with barren caverns (I test 2-3 locations for each gen, and they all have the same problem).
Does anyone know where I might be going wrong? I've copied the world gen for my most recent world below...
Created in DF v0.34.11.
[WORLD_GEN]
[TITLE:LARGE REGION]
[SEED:7PiozS6KcAjp17XFZCfo]
[HISTORY_SEED:FOqJQs1QQ3P0ZkdWHhBs]
[NAME_SEED:ZhWPX491R2rISBbvPjfm]
[CREATURE_SEED:MN6iqaI8iOgpUvaMcZva]
[DIM:257:257]
[EMBARK_POINTS:1324]
[END_YEAR:999]
[BEAST_END_YEAR:300:50]
[REVEAL_ALL_HISTORY:1]
[CULL_HISTORICAL_FIGURES:1]
[ELEVATION:1:400:800:800]
[RAINFALL:0:100:400:400]
[TEMPERATURE:25:75:400:400]
[DRAINAGE:0:100:400:400]
[VOLCANISM:0:100:400:400]
[SAVAGERY:0:100:400:400]
[ELEVATION_FREQUENCY:1:1:1:1:1:1]
[RAIN_FREQUENCY:1:1:1:1:1:1]
[DRAINAGE_FREQUENCY:1:1:1:1:1:1]
[TEMPERATURE_FREQUENCY:1:1:1:1:1:1]
[SAVAGERY_FREQUENCY:1:1:1:1:1:1]
[VOLCANISM_FREQUENCY:1:1:1:1:1:1]
[MINERAL_SCARCITY:1500]
[MEGABEAST_CAP:75]
[SEMIMEGABEAST_CAP:150]
[TITAN_NUMBER:33]
[TITAN_ATTACK_TRIGGER:80:0:100000]
[DEMON_NUMBER:52]
[NIGHT_TROLL_NUMBER:26]
[BOGEYMAN_NUMBER:26]
[VAMPIRE_NUMBER:26]
[WEREBEAST_NUMBER:26]
[SECRET_NUMBER:52]
[REGIONAL_INTERACTION_NUMBER:52]
[DISTURBANCE_INTERACTION_NUMBER:52]
[EVIL_CLOUD_NUMBER:26]
[EVIL_RAIN_NUMBER:26]
[GOOD_SQ_COUNTS:100:1000:2000]
[EVIL_SQ_COUNTS:100:1000:2000]
[PEAK_NUMBER_MIN:50]
[PARTIAL_OCEAN_EDGE_MIN:2]
[COMPLETE_OCEAN_EDGE_MIN:0]
[VOLCANO_MIN:200]
[REGION_COUNTS:SWAMP:1032:7:6]
[REGION_COUNTS:DESERT:1032:7:6]
[REGION_COUNTS:FOREST:4128:13:12]
[REGION_COUNTS:MOUNTAINS:8256:9:9]
[REGION_COUNTS:OCEAN:8256:7:6]
[REGION_COUNTS:GLACIER:0:0:0]
[REGION_COUNTS:TUNDRA:0:0:0]
[REGION_COUNTS:GRASSLAND:8256:13:12]
[REGION_COUNTS:HILLS:8256:13:12]
[EROSION_CYCLE_COUNT:250]
[RIVER_MINS:400:400]
[PERIODICALLY_ERODE_EXTREMES:1]
[OROGRAPHIC_PRECIPITATION:1]
[SUBREGION_MAX:2750]
[CAVERN_LAYER_COUNT:3]
[CAVERN_LAYER_OPENNESS_MIN:99]
[CAVERN_LAYER_OPENNESS_MAX:99]
[CAVERN_LAYER_PASSAGE_DENSITY_MIN:1]
[CAVERN_LAYER_PASSAGE_DENSITY_MAX:1]
[CAVERN_LAYER_WATER_MIN:1]
[CAVERN_LAYER_WATER_MAX:100]
[HAVE_BOTTOM_LAYER_1:1]
[HAVE_BOTTOM_LAYER_2:1]
[LEVELS_ABOVE_GROUND:15]
[LEVELS_ABOVE_LAYER_1:5]
[LEVELS_ABOVE_LAYER_2:1]
[LEVELS_ABOVE_LAYER_3:1]
[LEVELS_ABOVE_LAYER_4:1]
[LEVELS_ABOVE_LAYER_5:2]
[LEVELS_AT_BOTTOM:1]
[CAVE_MIN_SIZE:5]
[CAVE_MAX_SIZE:25]
[MOUNTAIN_CAVE_MIN:100]
[NON_MOUNTAIN_CAVE_MIN:200]
[ALL_CAVES_VISIBLE:0]
[SHOW_EMBARK_TUNNEL:2]
[TOTAL_CIV_NUMBER:40]
[TOTAL_CIV_POPULATION:15000]
[SITE_CAP:1500]
[PLAYABLE_CIVILIZATION_REQUIRED:1]
[ELEVATION_RANGES:8256:16512:8256]
[RAIN_RANGES:8256:16512:8256]
[DRAINAGE_RANGES:8256:16512:8256]
[SAVAGERY_RANGES:8256:16512:8256]
[VOLCANISM_RANGES:8256:16512:8256]