Autochthonous

[ɔ:'tɔkθәnәs]

(adj.) of rocks, deposits, etc.; found where they and their constituents were formed .

Edited by Bryan--From WordNet

(a.) Aboriginal; indigenous; native.

Checked by Darren

a. Aboriginal, original, primitive, primeval, pristine, primary, first, native, indigenous.

Inputed by Bess