Natural gas prices have steadily increased over the past decades. This has spurred interest in the development of unconventional gas resources, such as gas shales. The U.S. Energy Information Administration projects that by 2030, half of the natural gas produced in the U.S. will be from gas shale. Currently, the majority of U.S. gas shale production came from four basins:

Question

San Juan Basin, New Mexico/Colorado
Barnett Shale, Fort Worth Basin, Texas
Antrim Shale, Michigan
Appalachian/Ohio shales
This research focuses on the Marcellus shale, located in the Appalachian region. Shale is the common name for rock that was once layers of clay or mud. Due to geological conditions within the earth, these layers were compressed into a fine-grained sedimentary rock. The Marcellus shale is a Devonian-era shale, which means it originated 350 – 415 million years ago. A lot of algae and other organisms died and fell to the bottom of a sea that covered what is now the eastern half of the U.S. Layers of sediment were built up over the organisms, which eventually provided the carbon that has been converted into hydrocarbons such as methane gas and crude oil. It is estimated by Terry Engelder and Gary Lash, professors of geosciences, that the entire Marcellus shale contains 168 trillion cubic feet of gas in place. Gas in place refers to the total amount of gas present in the rock. When experts calculate the size of a gas reserve, they usually consider only 10% of gas in place as being technically recoverable. How much recoverable shale is present is based on several factors, described by the U.S. Department of Natural Resources. They include:
how much organic matter is present
what type of organic matter is present: gas-rich or oil-rich
amount of clay present
how deeply buried the deposits are
brittleness versus ductility of deposits
how much natural fracture is present
That means, on the low size, the Marcellus shale is a potential resource of 16.8 TCF, and on the high side, 50 TCF. In 2006, the U.S. consumed more than 21 TCF of natural gas. If Engelder and Lash’s estimates are correct, gas from the Marcellus shale could support this level of consumption for 1 to 2.4 years.

Cite evidence in the passage that indicates the Marcellus shale is a non-renewable fuel resource.
Responses
A The Marcellus shale could support the current level of gas consumption for 1 to 2.4 yearsThe Marcellus shale could support the current level of gas consumption for 1 to 2.4 years
B The remains of organisms were converted into hydrocarbons such as methane gas and crude oil.The remains of organisms were converted into hydrocarbons such as methane gas and crude oil.
C The Marcellus shale is a Devonian-era shale, which means it originated 350 – 415 million years ago.The Marcellus shale is a Devonian-era shale, which means it originated 350 – 415 million years ago.
D Due to geological conditions within the earth, deposited layers were compressed into a fine-grained sedimentary rock.Due to geological conditions within the earth, deposited layers were compressed into a fine-grained sedimentary rock.

Answer 1

The best evidence in the passage that indicates the Marcellus shale is a non-renewable fuel resource is:

C. The Marcellus shale is a Devonian-era shale, which means it originated 350 – 415 million years ago.

This statement highlights the geological age of the Marcellus shale, indicating that it took millions of years to form, which is characteristic of non-renewable resources that cannot be replenished in human timescales.