Clinker is formed by seams of lignite coal igniting surface fires that bake sediments and clay in ground into a natural brick. I just so happens that the vast majority of topsoil in the Bakken in composed of clinker rock. The diagram below from the American Geophysical Union depicts the formation the causes clinker to be produced:
From subtle rolling hills to vast rugged formations, clinker is an iconic depiction of the North Dakota landscape. Currently clinker is the typical material excavated during well pad grading, and it is also commonly re-used. It is most frequently used to surface roads and well pads –which is a significant advantage considering the tripling of gravel prices in the Bakken since the boom.
Along with gravel, nearly all construction materials in the region have inflated costs due to high demand and lacking local supply networks. As I read more about clinker and construction material shortages, I began to ponder what else clinker could be used for in buildings.
Clinker is a term commonly found in another major production industry –cement. Clinker in this context describes the gravel-like product of kiln firing crushed limestone. This is done to achieve the necessary hardness to mill it into cement. Kiln firing crushed limestone is easily the most energy intensive component of cement and concrete production. Herein lies the speculative proposal: to manufacture cement and concrete using natural clinker –with no need for facilities and energy required for kiln firing.
Only a mill factory would be needed to convert the abundance of natural clinker into cement for concrete. The most durable construction material could be completely sourced within a 100 mile radius of Williams and McKenzie counties. Clinker is also described as being similar to pozzolana -an additive to cement to give the concrete a subtle reddish hue. Concrete of this type is most notably used in Luis Kahn’s Salk Institute in La Jolla. This may serve as a material inspiration if this potential supply source were to be developed and incorporated into design.