Heres a list of notable stuff I found yesterday.
-885, 1203 Had to create a stairway as the tunnel is close to vertical and theres a waterfall inside it. Decided not to continue as it leads to the roof of a cavern. Same abandoned mine as -722, 1388?
-928, 1228 large passageway leads to ravine.
-909, 1160 hole above ravine. Just thought I'd take note of this.
-722, 1388 Abandoned mine, entrance established, cave spiders. This one is right next to the oasis I am making. I was investigating mob noises when I found this. There is a passageway that leads directly to the abandoned mine. I only explored the entrance area since I kept getting mobbed by cave spiders and had to retreat, I suspect there is a spawner close by and I think I know where one might be. Anyways, I'm asking for assistance in spelunking this.
There is a small side passage which is a bit of a drop, but it's a dead end and I've blocked it off, the chamber behind the stairs I made is just an area that I dug alot of gravel out of.
Whether that one connects to the one I spotted in the swamps, I have no idea.
Also, would it be useful to have diamond shovels? I have one with maybe 5% durability remaining and another with 99% durability remaining. Obviously it would be kind of a waste considering that shovels are less durable than picks and diamond is rare.