Ravine Culture at Blood Hill, Ashby

I am going to describe four large structures I found following a ravine uphill  to a pass between summits at Blood Hill (the blue path on the map). The last one is a huge J-shaped mound I have described before [see here]. But since then I have seen a few other things that help to put this in perspective. 
At Blood Hill, I saw large messy mounds along the edges of the ravine, very similar to something at Lovell Reservoir [click here] and another thing at the ultimate Falulah headwater [click here]. These sites are all in the same part of northern Fitchburg and Ashby, so this "ravine culture" is slightly local. As I wrote about the Falulah: "I saw piling along the side of the watercourse that was messy and consistent with field clearing. ".
This was exactly my first impression at Blood Hill. 

Let me describe this structure in detail, so we can take as close a look as possible. First of all the rocks are graded with large ones in the middle and a heap of smaller ones at the upper right . From a different view we will see that mid sized rocks appear at the lower left. Rocks sorted by size is characteristics of field clearing. I have to convince myself this is not field clearing. It is worth noticing casually that the large rocks are ledge rocks, not from a field. Examining it more closely we see:
The 'heap' of smaller rocks is a well layed pavement:

And at the lower end, there is something distinctly structural and suspicious. Looks like a hollow:

I payed close attention to this:

 

Especially the pieces of quartz on the left and right.

Seen in the context of the adjacent stone walls:

The picture cuts off the way the wall continues to the lower left. The extra boulder inside the gap is interesting.

Let's continue up the ravine. The next example is messier:

Here is another small "pavement" of small rocks.

Structure hun?

Let's continue. Here is a 3rd structure:

 A view of its upper surface:

Here we are looking at it in back of a bushes and a stone wall with nice piece of quartz.

These first three large structure were within a short distance (100 yards or less) from each other. I guess I was going over a knoll and saw this:

 Somebody or something has been making a trail across this. It looks like a messy stone wall that joins up with a more regular wall in the background. If we take a close look, it has a little white rock one the side (in this case feldspar):

After this I got into the main gully and got to the ultimate rock pile - the Blood Hill "J". It was of a kind with these smaller features. It has the white quartz at either edge.

If you right-click-open-in-new-tab you can enlarge enough to see the quartz at either end. 

Closer, on the left:

 And on the right:

This is a magnificent structure. The whole ravine should be a museum. 

There is more. At the end of the first leg of the red path (which starts where the blue one ends). I'll show them later.