Shatter curves and choose left segment of curves

Hi everybody!
I created a set of curves and want to choose left side of curves (look on the picture)


I want to find an automatic way to choose leftmost curves
I will be glad of any help


Error-230503.gh (39.2 KB)

Hi,

Have a look at this.

Your Brep is not very clean, so not sure this will be very robust.
The idea is to isolate the border to the left on the bottom, use those edges to isolate the surfaves to the left, then Contour.

Error-230503.gh (46.4 KB)