An Instructional Unit on the Marcellus Shale for Middle School Students
Learning Objectives
Students investigate relevant geologic, environmental, and social issues for this particular natural gas formation along with energy exploration in general.
Standards Addressed
Within standard area 3.3.A Earth Structure, Processes and Cycles, apprpriate for grade bands 8-12.
3.3.10.A1: Earth features and the processes that change it
3.3.10.A8: Science as inquiry
Preparation Time Needed
2-3 hours in total, as there are several days of activities.
Class Time Required
This article presents a five-day instructional unit organized to engage students in the scientific foundation of a topic that has widespread and far-reaching political and economic significance in many parts of the nation.
Activity Description
Central Pennsylvania is an area rich in natural energy resources with a complex geologic history. Classroom investigations often focus on how the modern regional topography developed following formation of the Appalachian Mountains. The last ten years have seen tremendous interest in utilizing natural gas, especially from the Marcellus Shale, as an alternative to coal and petroleum for providing electricity and transportation fuel. This article presents a Marcellus Shale instructional unit spanning five instructional days as part of a cohesive Earth Science curriculum for middle school students in central Pennsylvania. Students investigate relevant geologic, environmental, and social issues for this particular natural gas formation along with energy exploration in general. The Marcellus Shale instructional unit consists of readings, in-class instruction and activities that help students to connect this content with preceding and subsequent learning.
Unit Components and Implementation
This article presents a five-day instructional unit organized to engage students in the scientific foundation of a topic that has widespread and far-reaching political and economic significance in many parts of the nation. The unit is organized around multiple instructional components:
- Day 1: Introductory slide-show evoking prior knowledge, followed by a hands-on activity to investigate the energy resource properties of local sedimentary rocks
- Day 2: Simulated hydrocarbon prospecting activity
- Day 3: Exploration of an online Marcellus information resource
- Day 4: Class discussion of benefits and challenges in energy exploration
- Day 5: Writing a position letter regarding hydrofracturing to extract natural gas
The variety of activities allows students to become involved in constructing their own knowledge regarding our hydrocarbon-based natural resources. Some of the components lend themselves to stand-alone use, while others are best contextualized within a longer unit.
Day 1: Geologic Formation of Sedimentary Rocks and Minerals
Through prior learning and in-class discussion, students are reminded how shale forms, including the time scale of its formation. This step can be carried out effectively by connecting this lesson to an immediately preceding unit on the geomorphology of central Pennsylvania (Ellis et al., 2009). Through use of a slide-show based discussion, the location of the Marcellus Shale resource play is introduced to the students so they can begin to identify the geological features and rock types associated with this formation. A resource play, often abbreviated as play, is a term used to describe large, known sources of gas trapped beneath the earth’s surface (Encana, 2013). A typical cross sectional map of central Pennsylvania geology is shown to the students with the location of the Marcellus Shale indicated. In addition to observing and describing important sedimentary rocks, students also make their own sedimentary rock using Epsom salt, water, gravel and sand (Rogers Group Inc., 2011). This activity focuses on lithification processes. In the first trial of this experiment, other mineral salts were substituted for Epsom salt, with limited success. Subsequent trials with Epsom salt have proven successful. The variation of grain size between gravel and sand leads to “rocks” with different pore spaces, which directly connects student thinking to the next section.
Day 2: Hydrocarbon-Based Fuels and Formation
The students read about different types of hydrocarbon fuels (i.e., fuels that primarily contain the elements hydrogen and carbon) such as natural gas, coal, and crude oil. Reading resources included description of the chemical and physical properties involved in the formation of these fuels via different geologic processes. Petroleum and natural gas are the primary focus of this part of the unit since the two form through similar processes and therefore share chemical and physical properties. The burial of the organic matter followed by its transformation into the different fuels and their migration underground is also discussed. In order to demonstrate the importance of pore space to the formation of reservoirs, reference is made to the rock formation activity of the previous day. Demonstration can even be made with those artificial rocks by pouring vegetable oil through them. Alternatively, if the rock formation activity has been omitted, an investigation of pore space can be done independently (Women in Mining Education Foundation, 2007). Either activity directly leads to discussion of the relationship between energy-bearing shales, sandstone reservoirs, and capstone rock formations. The role of shales in formation and entrapment of these hydrocarbons is also explored. Students view a map of Pennsylvania that shows the locations of various petroleum and natural gas fields. The many byproducts of hydrocarbons and their impacts on our daily lives are also discussed.
This reading, demonstration and discussion lays the foundation for an oil-prospecting activity targeted at allowing students to use critical thinking skills to identify where oil is most likely to be trapped. Depending on the type of hydrocarbon, different hydrocarbon exploration techniques are used. The activity is adapted from one used by Furman in a Pennsylvania State University introductory geosciences course and is available from http://www.paesta.psu.edu; a simplified version that introduces the concept of hydrocarbon migration can be found online (Kluge, 2013). Students first apply the skills from the prior unit (Ellis et al., 2009) in determining the arrangement, folding, and faulting of rock layers on a cross section that includes possible drilling locations. Students then choose where to distribute their investments ($50,000 in $10,000 lots) between the six possible wells. In addition to drawing in the layers and choosing the wells, students must provide to their theoretical investors a justification for why they should invest in those locations. In the end, each well is given a value in oil that would be obtained there and distributed amongst those investors based on the number of lots put into that well (number of $10,000 investment increments). The winning student is the one who makes the most profit, which could mean choosing a well that produced less but that was selected by fewer other investors.
Day 3: Details of the Marcellus Shale Formation
Next, more specifics about the Marcellus Shale Formation, including its broad geographic expanse, are presented and discussed. Compared to conventional natural gas removal, the natural gas from the Marcellus Shale Formation needs to be extracted using a different technique. Recent technological developments in hydraulic fracturing (a.k.a. fracking) and deep lateral drilling have allowed extraction from this formation to be possible as well as economically feasible. Students spend a day learning about and discussing the technology involved in reaching the Marcellus Shale. This involves use of a video about horizontal well drilling and hydraulic fracturing, which can be obtained from the Marcellus Center for Outreach and Research. Students explore the factors that make the Marcellus Shale Formation so different from conventional natural gas reservoirs and why different methods and technologies are required for removal. The authors are fortunate to have access to a local expert on Marcellus Shale who speaks about the rocks, the extraction processes and related environmental concerns.
Day 4: Energy in the United States
Students explore individually the website exploreshale.org, which provides information about how water is used in fracking. Students learn about the consequences of removing natural gas using different methods and technologies, including water quality concerns involving the chemicals used in the fracking extraction process. Students are encouraged to consider and document how extracting and using natural gas from Marcellus Shale compares to extracting and using other energy sources, which will aid them when preparing the upcoming assignment described in Day 5. After individual examination, the students, as a group, discuss their findings. This activity ties into a reading initiative at Brightbill’s school where students learn a standard way to read and annotate documents. Students are required to comment on 5 different aspects of the website, discuss them in small groups, and bring the biggest issue or two from each group to the whole class.
The final component of the unit focuses more broadly on the different types and uses of energy sources in the United States. Students learn how different sources of energy (petroleum, natural gas, coal, nuclear and renewable options) are allocated, or assigned, to certain sectors in the United States like transportation and electricity, and how energy consumption has changed over time. For example, the attached figure shows how petroleum, natural gas, coal, renewable sources and nuclear energy are allocated to the transportation and residential electricity sectors. The United States is most dependent on petroleum for transportation needs, while the residential electricity sector has a diversified portfolio of energy sources. The concerns of using fossil fuels (i.e., greenhouse gas emissions) and the present day and future impacts on society are discussed. Supplemental information for this discussion, including descriptions of coal, petroleum and natural gas and their geographic distribution can be found in Bembenic et al. (2012) and at The Coal and Energy Unit.
Day 5: Position statement on hydraulic fracturing
On the final day of this unit, students are asked to apply their scientific understanding of energy resource distribution and extraction to the social and political arena. Each student writes a one-page position statement regarding the appropriate regulation of hydraulic fracturing use in deep gas resource plays in the central Appalachians. The students are to choose a side and support it with at least 3 valid reasons. In Brightbill’s case, letters were written to Pennsylvania State Representative, Scott Conklin, but many other policy makers are equally reasonable, including state, local and national officials in the energy and environmental fields. This activity promotes clear communication of scientific ideas, and has, for maximum impact, been implemented successfully as an assignment between science and language arts teachers.
