Eric Hiatt Earth Resources Page

Part XI. Earth Resources (Chp. 12 in Textbook).

A. Society, Population and Resources.

We live in a society that consumes vast amounts of resources.

Today there are about 6.9 billion people on the Earth. About 1 billion people have relatively high standards of living and about 5.9 have very low standards of living. Those 5.9 billion are striving to raise their standards of living -- they would like to have refrigerators, air conditioning, heat in the winter, cars, computers, etc. The basic problem is that there are not enough resources (metals, fossil fuels, etc.) on the Earth for even half of the people to have these things. More on the population story from NPR.

B. Energy Resources.

1. Most of our energy comes from fossil fuels, such as coal and petroleum.

2. Coal.

a. Coal forms from alteration of thick accumulation of plant material in the absence of oxygen.

b. The U.S.A. has large reserves, but most of the easily accessible deposits will be exhausted within the next 70 years. You will often hear politicians and others say that the U.S.A. has coal reserves that will last for hundreds of years. That figure is wrong and comes from a report published back in the 1970's. What is lost when this figure is cited is the accompanying qualifier "at current rates of consumption". Consumption rates today are much higher than in the 1970's and rates of consumption are still increasing today.

c. Problems:

Most coal deposits contain pyrite. When pyrite is burned, sulfur dioxide gas is produced, which in the atmosphere combines with water and makes acid rain. Mining operations often produce acid mine drainage through oxidation of pyrite by rain and groundwater.

Many coal deposits contain mercury (as well as uranium, vanadium, selenium, etc.). Mercury is released into the atmosphere when coal is burned and then bacteria in lakes, rivers, and wetlands convert it to a form that fish and other aquatic (and marine) organisms bioaccumulate. Here is a web site from the U.S. EPA that explains this mercury cycle.

Burning coal releases vast amounts of carbon dioxide (greenhouse gas) to the atmosphere.

3. Petroleum. Petroleum is relatively rare on the Earth (it makes up less than 0.000001% of the Earth)

a. To form petroleum:

Need an organic matter-rich source rock (almost all source rocks that produce petroleum are marine, but some were formed in lakes).

The source rock needs to be slowly heated to ~80 degrees C (about the temperature of a hot cup of coffee) and up to 170 degrees C (usually corresponds to 1.5 to 3.5 km burial depth within the Earth).

Need to store the petroleum generated in porous and permeable reservoir rocks (analogous to an aquifer in hydrology).

Need a way to hold or trap the lighter-than-water petroleum within the Earth. Without a trapping or sealing mechanism, petroleum would float to the surface of the water table where it is attacked by bacteria. Most of the petroleum that ever formed on the Earth has long since leaked to the surface and was broken down and destroyed by bacteria and reaction with oxygen. Only in rare cases was it trapped in a system that did not leak.

b. How much is there, who has it, and where does it go?

The U.S.A. has about 2 % of world petroleum reserves.

The U.S.A. uses about 25% of the world's petroleum production.

The middle east region contains about 65% of the world total petroleum reserves.

Currently, the U.S.A. produces about the same amount of petroleum as Saudi Arabia, but the U.S. produces this from about 500,000 wells, Saudi Arabia's comes from about 1500 (really big) wells.

Here is a short story with audio that has a simple explanation of how petroleum forms and discusses oil in the Gulf of Mexico (made during the BP oil spill, August 2010).

Alternatives to Petroleum:

Ethanol: Here is a two-part series from NPR on ethanol that deals with costs and benefits. This one discusses the geopolitical and efficiency issues, and this one deal with ethanol's effect on food prices.

Simple things to decrease petroleum consumption: inflate tires to proper level, accelerate slowly, replace your air cleaner filter, drive a fuel-efficient car.

Here is a great site from Energy Literacy Advocates that has basic facts and figures on petroleum use in the U.S. and world.

Click here to go to the Population Clock at the Office of Population Research at Princeton University, click here for the Population Information from the U.S. Census Bureau, or here for the Population Reference Bureau.

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A. Society, Population and Resources.
	We live in a society that consumes vast amounts of resources. Today there are about 6.9 billion people on the Earth. About 1 billion people have relatively high standards of living and about 5.9 have very low standards of living. Those 5.9 billion are striving to raise their standards of living -- they would like to have refrigerators, air conditioning, heat in the winter, cars, computers, etc. The basic problem is that there are not enough resources (metals, fossil fuels, etc.) on the Earth for even half of the people to have these things. More on the population story from NPR.

B. Energy Resources.

1. Most of our energy comes from fossil fuels, such as coal and petroleum.
2. Coal. a. Coal forms from alteration of thick accumulation of plant material in the absence of oxygen. b. The U.S.A. has large reserves, but most of the easily accessible deposits will be exhausted within the next 70 years. You will often hear politicians and others say that the U.S.A. has coal reserves that will last for hundreds of years. That figure is wrong and comes from a report published back in the 1970's. What is lost when this figure is cited is the accompanying qualifier "at current rates of consumption". Consumption rates today are much higher than in the 1970's and rates of consumption are still increasing today. c. Problems: Most coal deposits contain pyrite. When pyrite is burned, sulfur dioxide gas is produced, which in the atmosphere combines with water and makes acid rain. Mining operations often produce acid mine drainage through oxidation of pyrite by rain and groundwater. Many coal deposits contain mercury (as well as uranium, vanadium, selenium, etc.). Mercury is released into the atmosphere when coal is burned and then bacteria in lakes, rivers, and wetlands convert it to a form that fish and other aquatic (and marine) organisms bioaccumulate. Here is a web site from the U.S. EPA that explains this mercury cycle. Burning coal releases vast amounts of carbon dioxide (greenhouse gas) to the atmosphere.

3. Petroleum. Petroleum is relatively rare on the Earth (it makes up less than 0.000001% of the Earth) a. To form petroleum: Need an organic matter-rich source rock (almost all source rocks that produce petroleum are marine, but some were formed in lakes). The source rock needs to be slowly heated to ~80 degrees C (about the temperature of a hot cup of coffee) and up to 170 degrees C (usually corresponds to 1.5 to 3.5 km burial depth within the Earth). Need to store the petroleum generated in porous and permeable reservoir rocks (analogous to an aquifer in hydrology). Need a way to hold or trap the lighter-than-water petroleum within the Earth. Without a trapping or sealing mechanism, petroleum would float to the surface of the water table where it is attacked by bacteria. Most of the petroleum that ever formed on the Earth has long since leaked to the surface and was broken down and destroyed by bacteria and reaction with oxygen. Only in rare cases was it trapped in a system that did not leak. b. How much is there, who has it, and where does it go? The U.S.A. has about 2 % of world petroleum reserves. The U.S.A. uses about 25% of the world's petroleum production. The middle east region contains about 65% of the world total petroleum reserves. Currently, the U.S.A. produces about the same amount of petroleum as Saudi Arabia, but the U.S. produces this from about 500,000 wells, Saudi Arabia's comes from about 1500 (really big) wells.
Here is a short story with audio that has a simple explanation of how petroleum forms and discusses oil in the Gulf of Mexico (made during the BP oil spill, August 2010).
Alternatives to Petroleum: Ethanol: Here is a two-part series from NPR on ethanol that deals with costs and benefits. This one discusses the geopolitical and efficiency issues, and this one deal with ethanol's effect on food prices.
Simple things to decrease petroleum consumption: inflate tires to proper level, accelerate slowly, replace your air cleaner filter, drive a fuel-efficient car.
Here is a great site from Energy Literacy Advocates that has basic facts and figures on petroleum use in the U.S. and world.

Click here to go to the Population Clock at the Office of Population Research at Princeton University, click here for the Population Information from the U.S. Census Bureau, or here for the Population Reference Bureau.