Lesson 1.3: Where Are All of These Mines?
Lesson 1.3: Where Are All of These Mines? ksc17A note about the Figures and Data in this lesson:
The graphics and data in this lesson are from 2017. Visit this Centre for Disease Control and Prevention/NIOSH Mining interactive website for the latest and most updated information.
The most recently available data shows that we have over 13,000 mines in the U.S. By law, all mines must be registered with the U.S. Mine Safety and Health Administration (MSHA), and by analyzing their database, we can learn much about mining in this country. For example, we can determine the number of mines by commodity, size, and location. Back to the question: where are these mines? They’re everywhere, and you probably didn’t realize it! Take a look at Figure 1.3.1 below, which shows the location of these mines by major sector, i.e., metal, nonmetal, and coal.
Before examining this map more closely, we should address the related question: why are they where they are? What do you think?
First and foremost, the availability of the mineral resource will dictate where we mine. Although minerals of nearly every variety are found through the crust of the Earth, it is relatively rare to find a concentration of a particular mineral to justify a commercial mining activity. Of course, the relative rarity of an economic concentration depends on the commodity. If we want to mine gold, for example, there are a limited number of locations where we will find economic concentrations. On the other hand, if we want to mine stone for construction purposes, we can find it almost anywhere.
Let’s say we know of an economic deposit. Are there are other factors that would determine whether or not we would open a mine at that location? Yes, absolutely there are, and we will look at that in more detail later in this course. For the purposes of this discussion, I’ll bring one additional consideration to your attention with the following example. Economic deposits of metals exist in the densely populated areas of the East Coast. Decades ago, there were commercial metal mining activities, e.g., New Jersey Zinc Company. Today, there are none. Why? The land is so valuable that it would be prohibitively expensive to acquire it, and urban zoning ordinances severely restrict mining operations. Now, with this background, let’s take a closer look at the locations of these mines.
The metal and nonmetal mines encompass the nonfuel minerals. For reasons that may become clear as we go through this course, a variety of terms, which are similar if not synonymous, are used by geologists, mining engineers, and government regulators. Anyway, the location of the metal/nonmetal mines is shown in Figure 1.3.2.
We can go down one additional level, and separate the metal from the nonmetal mines, as shown in Figures 1.3.3 and 1.3.4.
Stone, sand, and gravel mines are generally grouped together and are separated from metal/nonmetal mines, even though these commodities qualify as nonmetal. For clarity, the stone mines are shown separately from the sand and gravel mines in Figures 1.3.5 and 1.3.6. As you can see, the number of mines is remarkably large. They are everywhere! Why are they everywhere? Simply, several different minerals can be used as aggregates, i.e., stone, sand, and gravel; and as such, they are readily found throughout the U.S. Just because we have a mineable deposit, do we have a need for a mine? No! What else do we need? There must be a demand for whatever we are going to mine, i.e., we need a market for the mined product. Aggregates are used for what purpose? The primary use is in construction – construction of houses, buildings, roads, and so on. Thus, there is a strong demand for aggregates wherever people live and work, and this is evident from the maps.
1.3.1: Where Are All of These Mines? Continued
1.3.1: Where Are All of These Mines? Continued ksc17Next, let’s look at the fuel minerals, and specifically coal. After looking at Figure 1.3.7, examine the USGS map of U.S. coalfields in Figure 1.3.8. Do you see the correspondence between the coalfields and the location of coal mines? There is a lot of detail to be gleaned from this figure, and I suggest you zoom in and take a closer look. Take note of the rank of the coal found in the different coalfields, and also note the relatively few locations in which metallurgical-grade coal is found.
These figures that we’ve just examined are helpful as we endeavor to learn major characteristics of the U.S. mining industry. There are many ways to “slice and dice” the available data, depending on your specific interests.
1.3.2: Where Are All of These Mines? Continued
1.3.2: Where Are All of These Mines? Continued mjg8In this lesson, I want you to look at a few additional representations. The Mineral Commodity Summaries are published on an annual basis. This report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. This publication will break out in more detail the major metal and nonmetal (industrial mineral) mining regions by commodity. Spend some quality time reading and analyzing the Mineral Commodity Summaries to view the figures of the relative economic value or significance of mining in specific regions. The economic value of metals mined in the U.S. is shown by region. We can examine industrial minerals in the same fashion, starting this time with the economic value of industrial minerals production by state. We can then go to a more detailed commodity map to see not only the location at which the major industrial minerals are mined, but also which ones are contributing to the economic value within a given state or region.
Finally, I would close this discussion that has focused on the location of mining activity with a different perspective on the location of mines. We now understand the geographic dispersion of mining activity as well as the concentration of mining in certain areas for certain commodities. A different twist to the question, where are these mines?, is: are these mines located on the surface or are they deep beneath the surface? Figures 1.3.9 and 1.3.10 clearly show that most mining occurs in surface rather than underground mines, by a ratio of nearly 15:1. We’ll examine the reasons for this later in the course, but an important point now is that most of these mines are located on the surface.
In this lesson we’ve learned where the fuel and nonfuel minerals are mined, and we’ve developed a better understanding of the extent of mining activities. Soon, we will be ready to look at the life cycle of mining operations and the engineering associated with each part of the cycle. Prior to doing so, there is one last overarching topic to cover, and that is mining in today’s world.