Shale

Shale1	Shale1 -detail1	Shale2	Shale2 -detail
Shale6	Shale6 -detail1	Shale6 -detail3	Shale8
Shale8 -detail1	Shale9	Shale9 -detail	Shale10
Shale10 -detail	Shale15	Shale17	Shale17 -detail1
Shale 18	Shale Cut	Rotten Shale Hilltop	Weathered Mesa

Click on thumbnails for details

Shale is one of the most common rock types, and if you include similar sedimentary rocks with obvious, thin layering, then it is clearly the most common thing to find in railroad rock cuts world wide.  Sedimentary rocks come in all types and gradations: sandstones, mudstones, siltstones, and shales.  All of them can be modeled, in any scale you want, with Rubber Rocks. Limestones are included in that category, too, but they’re sufficiently different so that we’ll talk about them separately.

Two things dictate how sedimentary rocks like shale look:  the color of the rock, and the shapes of the rock blobs.  Coloring is up to you of course.  But we can offer pretty much any shape you want.  Our Shale product line includes 11 different Rubber Rocks, allowing you to model anything from the fresh-cut rock at the mouth of a tunnel to broken, weathered cliff faces that keep the civil engineers up at night worrying about landslides.

When we look at a rock cut, what do we see?  If the cut was made recently, or if the rock is very hard and resists weathering well, we may see something very angular, regardless of what the rock itself is made of.  The guys who made that cut didn’t remove any more rock than they had to, and the resulting surface when they got done is often  blocky looking, with only a little trace of the rock’s internal structure visible.  For places like this, consider our Shale Cut  There’s no doubt that the builders cut through layered rock here, but by and large the original, near-vertical surface of the excavation is intact.  It’s perfect for the approach to a tunnel, where the cut gets progressively deeper and steeper as you approach the portal.  Farther away, the effects of weathering are more apparent.  The cut becomes less steep, as we get to places where the softer beds are weathering away. 

Note that there are a few vertical cracks (they’re called joints by geologists).  If you are cutting and rearranging rubber rocks, these are natural places to hide a seam.  Just make a vertical cut in a low spot, then but them up against other rocks and hide the low spot with debris or foliage. That’s what nature does! 

Vertical joints allow  for water to percolate deep into the rock and weaken it.  In places where this is happening the result is something like you see with Shale 15.  This one makes a nice companion for Shale Cut.  Again, we have the nearly flat, vertical surface left behind by the guys who dug and blasted the cut.  But now, you can see that surface beginning to weather away.  All the sharp angles are gone  Again, at the top of the outcrop, there are no sharp angles.  The rock gut gradually blends into the soil which is forming as the rock weathers away.

For an example of how to cut and rearrange a Shale 15, click here.