Nice...very heavy duty!!!!!
That red soil you have is really something. We may find some red gooey clay 1-2 ft deep but mostly black soil on top of gravel. Is it clay or iron that gives it the red color?
Edit...what I found:
Many refer to this soil as Clay but actually the soil in Oklahoma is PORT. The color in the soil is caused by the breakdown of the rock or strata beneath the topsoil layers. Oxidation from water or air can create a breakdown effect we are use to seeing on an old chain or a corroded water pipe. The soil beneath our PORT soil is the clay rich strata that breaks down through weatherization, heat, compression and it is full of iron. Soils with high iron content tend to have a red color to it.