Thoughts about a "Ravine Culture" and piles in the shape of a wrench

I think I finally saw enough examples of a type of feature that something clicked in my mind and it became a familiar pattern - something shaped like a "wrench". This is a elongated mound with a hollow at one end, opening downhill (towards flowing water). I just drew this picture as an example:

I found an example along East Wachusett Brook, in Princeton MA, and was seeing its similarity with other piles I mentioned as the characteristic feature of the "Ravine Culture" at Blood Hill, Ashby MA. In that post I also mentioned other similar examples: Falulah, Lovell Reservoir, etc. With a widened perspective I make other connections and also remember another pile at the foot of Whittemore Hill in New Ipswich NH. Searching through old posts about that hill, imagine my pleasure to find this picture, along with this post: 

Another place turns up in my search was along Trapfall Brook, here. 

Places where I have seen this feature:

- E. Wachesett Brook, Princeton MA

- Falulah Brook, Fitchburg/Ashby MA

- Lovell Reservoir, Fitchburg MA

- Blood Hill, Ashby MA

- Whittemore Hill, New Ipswich NH

- Trapfall Brook, Ashby MA

A case could also be made that this shows up in Shirley at Spruce Swamp Brook - the easternmost example. I'll post photos and location for E. Wachusett Brook next.

We need a name for this type of feature. 

The word wrench is not particularly attractive but it is a reasonable reminder of the shape.I am going to go with "Long mound with hollow".