Finding Portals at the Top of Columns and Arches

One weird trick to recognize something as a portal, is to find it at the top of columns, like the green folliage at image G.

At the top of columns, there is usually a portal, meant to penetrate a barrier above it. But in the case of image G, the barrier is actually the upward bulging arch. My thinking about arch-and-columns symbols is evolving.

Image F is a torus symbol, it's upper arch could be considered a bulge marking a portal where the face is located at keystone position. Image F also has a downward bulge or a half-circle portal symbol. Not shown, but that lower half-circle could be steps instead, or step-pyramid, or just flat.

Image E is neat because it separate the upper arch into a half-circle portal symbol.

Returning to the image G green portals that seem like lettuce leaves, those confused me for quite a while. Similarly for image H which is like a vajra, a bidirectional flow symbol, and the letter "S" in image I and J, those are showing bi-directional flow from a portal too.

Image K has spheres at the top of columns, and spheres can certainly be portal symbols. And it has birds, showing the portal flow going vertically between wings. So yes, more and more, birds are turning out to be commonly used as portal symbols.

Image A is a torus but I added the yellow arrow to show "horizontal flow". Image B has no hint of that, just a North outflow at the top. Image C and D are using reptile faces to show a horizontal outflow.