7 most common drainage patterns?

Question

Dendritic, Rectangular, Trellis, Radial, Annular, Parallel, Deranged.

What are the conditions necessary for them to develop?

Answer 1

Dendritic (random) -along gentle slopes of land very little difference in erosional patterns because surface material erode at the same rate.

Rectangular - cracked and broken rock along faults and joints erode  with  greater difference than solid rock and  creates ridges and valleys

Radial - on domed structures with streams radiating  out  from a central point (IE Crater Lake in Oregon)  like spokes on a bicycle wheel, and having very little difference in erosion rates,  

Annular - (are like tree rings or concentric circles) form in dome areas with great  difference of erosion rates because of the capture of radial streams on  old dissected domes and basins  .

Parallel -  parallel master and tributary streams

Deranged - too young to decide what pattern they want to be until  they grow up.