Possible to spawn a world without sand?

"Lake" and "Ocean" seeds are actually kind of like easter eggs in the game. They are the only hardcoded seeds last time I checked the code. It certainly would be possible to add more for other biomes but thats ultimately up to Red51 to do that.

Quote from MommaT

I have a world that I think I seeded by typing Lake in the seed field. It has mountains, forests, temperate grasslands, and yes, lakes. It also has at least one snow biome. It does not appear to have any savannas, deserts or beaches. I have flown due east for more than 3 game days, what must be the equivalent of thousands(?) of miles. I haven't seen anything but the above forests and mountains. I am convinced the world has only these biomes. Is that possible?

Savannah and desert biomes are indeed extremely rare to find. I would think your world has at least one but you haven't found it yet (bad luck?) Also the direction you fly towards doesn't matter it is not like the worlds generate based on some geographical markers/profiles for regions i.e. sand is not necessarily east as in the real world I would try starting from my spawn and then flying in every direction to a distance 15000-17000, there must be at lest one Savannah biome in that circle.

Quote from MommaT

I should add that this is furthest I have been from base. the further I go the more it seems to lag. Is this common also? I am 37,774 (degrees?) east of my base. So, pretty far.

PS: a compass can only have 0-359 degrees that distance is in blocks i.e. you have travelled a straight distance of 37774 blocks from your spawn.

Quote from MommaT

I am 37,774 (degrees?) east of my base. So, pretty far.

Yes, pretty far, as the game goes, but this amounts to "only" 18,887 m, i.e. slightly less than 19 km from the world origin.