The process of metallurgy has been dated back to 6000 BC, when humans began using gold. Humans have been using the study of geology to their advantage as early as the Neolithic and Bronze Ages (5000 -2500 BC), when humans mined flint in what is now Europe. As early as 4000 BC, in some areas of the Middle East, people began mining for iron ore, gold, tin, clay, and copper.
During the Classical period, the Greeks, Arabs, and Romans gained a better understanding of Earth’s surface processes. In 540 BC, fossils of fish and shells were found on mountains and documented by Xenophanes. The cultures of the Classical Period attributed important surface processes to supernatural interference, until Aristotle proposed that strong winds from the center of the earth caused earthquakes and volcanic eruptions. Although Aristotle’s theory was incorrect, its validity stemmed from the alternate source of energy causing the phenomena.
In the Middle Ages, Leonardo da Vinci introduced the belief that fossils are remnants of dead organisms, and that there were changes in the sea and Earth. The work “De Re Metallica,” written by Georg Bauer cataloged the processes of mining, smelting, and refining of minerals. Other books were written during this era on the topic of fossils, stones, and processes involving minerals.
By the seventeenth and eighteenth centuries, advancements were made in more holistic ways, such as those made by Nicholas Steno. Steno made observations of rocks in a more general way than just focusing on mining. He studied the layers of sedimentary rock in Tuscany, and divided its formation into six phases. He incorrectly applied this idea of six phases of formation on a worldwide scale, but he gets points for making the first advancement in this field of geological study.
In 1756, a man named Johann Lehmann devised a system of classification for mountains. He stated that mountains were created either 1) When the world was created, 2) by sediments deposited in water, or 3) existed as volcanoes. The presence of fossils and appearance of mountains were the determining factors used to classify them. Perhaps the earliest correct theory made by scientists was that of a man named Pallas, who proposed a theory that the elevation of mountains is due to “commotions of the globe.” His “commotions of the globe” are what we now refer to as plate tectonics.
In 1726, the “father of modern geology” was born. This man, James Hutton, believed that certain rocks came from molten lava from inside the earth. This theory became known as Plutonism, and its followers were known as Plutonists. This theory opposed the earlier theory of Neptunism (Abraham Werner, 1749-1817), which stated that igneous rocks formed in an ocean that covered the sea. Perhaps Hutton’s most widely-regarded theory is that of uniformitarianism, which states that geologic processes that occurred in the past are still occurring in the present and will continue to occur in the future.