> It is the word 'trap' that I find impossible to explain. Can anyone suggest a
> meaning? Has 'trap' a geological or mineralogical meaning?
>
>
The word trap in this context is old geological nomenclature for the
iron-rich, feldspathic-augitic igneous rocks such as basalt and dolerite and
their varieties, so, yes, it refers to both the geological occurrence and
mineralogical composition of these rock types.
|