18a 7 letters Alayer of rock with varying thickness . I have E?R?T?M.
Erratum would fit but is there such a geological term?
I can't get to grips with this new Answerbank at all. What was wrong with the old style?
Thank you for any help
Thank you so much. I should really have known stratum, but my pop music knowledge is not so hot and I had suede instead of steps. I can't find the star rating otherwise you would all have had top marks.