During world generation, some lava fails to become obsidian when met with water. This is shown in the picture below.
How to recreate:
Go into world seed: 1273368191
Go to coordinates: 835, 11, 316
See for yourself
By the way, it's an underground ravine, if that's supposed to help
We're tracking this issue as MCPE-41103, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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