Which geologic era are we living in? paleozoic precambrian cenozoic mesozoic

Shaft mining is a form of underground mining where shafts are pushed vertically from top to bottom to excavate the ores and minerals. It is also called shaft sinking. It is best suited for concentrated minerals such as iron, coal, etc. which can be found at the depth of the earth's surface. It is found mostly all over the world. Shaft sinking refers to shallow shafts and it is different from a deep shaft. The former is sunk for the civil engineering projects and the latter is sunk for the mining projects. When the excavation is done on the ground surface, it is called a shaft and if it is on the underground it is called a sub-shaft. This is also known by the name Winze.