How to flattening curves representing geological horizons

Please I need help to know the algorithm of flattening curves of the annexed figure whichh represent a geological horizons (top of rock formations)

Thanks in adavance

[Tala]

what do you mean by flatening? draw a before after curve, also, attach your data please

[KSSV]

What do you mean by flatten? What output you expect? A pictorial example of the output will help us to help you.

[Moustafa Abedel Fattah]

I mean by flatten the horizons are not undulated but straight in horizontal (the reference of flattening is the value of minimum depth of each horizon)