What is geology?
The study of geology involves several related things: landforms of course, rocks and mineral discoveries and then their relation to land forms, crystal forms and their contribution to the classification of rocks and minerals, and fossils (paleontology) which both date and are dated by their enclosing rocks. All these together then allow the development of historical geology, in which the geologic record becomes a record of the earth’s past – ancient climates and ancient animals and plants.
Beginnings of geology
With whom did geology begin? With Adam and Eve, I suppose, if you consider who first saw mountains and rivers.
Flint work goes back tens of thousands of years – flint mines — were remembered and revisited on a regular basis because tools with sharp edges were so valuable.
Inconceivable as it may seem, the Timna Valley near Eilat at the north end of the Red Sea was mined for copper in the 5th millennium B.C. That’s seven thousand years ago! Copper is found as malachite, a striking greenish stone which must be smelted. How it was discovered that this stone yields copper is anyone’s guess. Perhaps such a stone was used for a fire pit and the discovery followed. Copper mines would eventually lead to the mining of copper ores with arsenic or tin as impurities, and the bronze that could be cast with these alloys of copper. Bronze may have started simply as the consequence of using impure copper ores, but these alloys are sometimes easier to cast and less apt to corrode, so (like many of life’s impurities!) they turn out to have their own value.
Somewhere long ago, gold was discovered. It is beautiful, shining even in its nugget form since it does not tarnish. It is easy to work with both because it is ductile rather than brittle, and so can be drawn out or hammered into incredibly delicate shapes. Egyptian jewelry of 3,000 B.C. was made with gold and precious or semi-precious stones.
There are coal stores at the location of forts along Hadrian’s Wall, so we know the Romans were using coal for heat, and therefore mining it, though not necessarily at any great depth. There are always places where it lies right at the surface, as a visitor to Pennsylvania can easily see. Coal can be made to yield a hotter fire than wood; such a hot fire is important for smelting and working iron. Interestingly, mining for ochre as a red or yellow pigment is associated with iron mining because this pigment is an iron oxide, and its sources are near sources of iron. Read about Clearwell Caves.
All this to say that mining was the practical study of geology in ancient times.
Notice the Universe 