ware . ▁ ▁Work ▁as ▁a ▁conservation ist ▁Pr eston ▁Labor ator ies ▁was ▁located ▁first ▁in ▁Butler , ▁then ▁later ▁moved ▁to ▁Mer id ian , ▁Pennsylvania . ▁Mer id ian ▁is ▁just ▁south ▁of ▁the ▁M ud dy ▁Creek ▁and ▁S li pp ery ▁Rock ▁Creek ▁valle ys . ▁These ▁valle ys ▁are ▁where ▁Pr eston ▁began ▁his ▁work ▁as ▁a ▁conservation ist . ▁Pr eston ▁walked ▁throughout ▁the ▁valle ys ▁and ▁mapped ▁their ▁ge ological ▁and ▁ge ographic ▁attributes . ▁He ▁discovered ▁gla cial ▁er rat ics , ▁k ett le ▁hole ▁b ogs ▁and ▁figured ▁out ▁how ▁the ▁m amm oth s ▁and ▁m ast od ons ▁migr ated ▁through ▁the ▁area ▁during ▁the ▁ice ▁ages . ▁ ▁On ▁a ▁trip ▁to ▁the ▁M ud dy ▁Creek ▁Valley ▁he ▁noticed ▁that ▁despite ▁the ▁bar ren ▁landscape ▁that ▁had ▁been ▁left ▁by ▁the ▁oil ▁well s ▁and ▁strip ▁mines ▁of ▁the ▁late ▁ 1 9 th ▁and ▁early ▁ 2 0 th ▁century , ▁the ▁valley ▁had ▁a ▁rich ▁natural ▁history ▁of ▁mor aines . ▁Pr eston ▁worked ▁to ▁form ▁the ▁Western ▁Pennsylvania ▁Conserv ancy , ▁which ▁purchased ▁the ▁land ▁that ▁became ▁M ora ine ▁State ▁Park , ▁re created ▁the ▁gla cial ▁landscape ▁and ▁preserved ▁open ▁spaces . ▁M ud dy ▁Creek ▁was ▁dam med ▁to ▁form ▁Lake ▁Arthur . ▁ ▁The ▁Western ▁Pennsylvania ▁Conserv ancy ▁worked ▁with ▁the ▁state ▁to ▁rec laim ▁the ▁land . ▁The ▁mines ▁were ▁se aled , ▁over ▁ 4 0 0 ▁oil ▁and