Algorithm for filtering and grouping geological points
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I have some geological points with [this][1] distribution:

I need an algorithm to filter desultory/single points and to group points which are adjacent. <br/>
I require the algorithm create something like [this][2] from above points for me<br/>

So after applying algorithm on first figure, I need three conglomerate of points, each one known as a critical section, be generated. (like figure 2)<br/>

I know some algorithms including Graph Partition, Convex Hull, Polygon Partitioning algorithms, but no one is typically suitable for this problem. <br/>

Do you know any specified algorithm for this question? <br/>


  [1]: http://sbu-alumni.ir/davoud/images/2.png
  [2]: http://sbu-alumni.ir/davoud/images/1.png