RCPL's Sanford Lab Wiki

What is it?

Geosciences

Geosciences is an umbrella for all the sciences that study the planet Earth's structure, evolution, and dynamics, as well as those of Earth's natural mineral and energy resources. Geosciences includes geology (the study of the Earth's history as recored in rocks), geophysics (geology that uses physical principals to study the Earth's properties), and geochemistry (the chemistry of the Earth's crust). Geosciences uses the record of history that is in rock to investigate how the Earth has been shaped throughout its 4,600 million years. Geoscience is founded on plate tectonic theory. This theory is that the Earth's lithosphere, or outer part, is made up of several interlocking, moving plates. The movement of these plates are either directly or indirectly involved in processes like earthquakes, mountain building, and volcanic activity¹¹.

Mining Engineering

Mining engineering is an engineering discipline that involves the practice, the theory, the science, the technology, and application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value ¹⁶.

DUSEL Focus

Rock Mechanics

Rock mechanics is an applied science within Mining Engineering. Its body of knowledge is made up of the following:

• mechanical properties of rock;
• methods of analyzing rock stress under some administered stress;
• established principles conveying the response of rock mass to load; and
• a logical process of applying these principles and methods to problems in the field.

Construction at the surface and subsurface, mineral recovery, geothermal energy recovery, and the isolation of subsurface hazardous waves are a few of the areas in which the application of the concepts in rock mechanics have exhibited their value to the industry¹.

Seismology

Seismology is the study of shockwaves that are made by disturbances, such as earthquakes, that spread throughout planets and the like. Seismographs measure the strength of these waves, as well as other characteristics. These measurements give scientists information about a planet’s internal structure. For example, these shockwaves can yield information about how a planet’s crust, mantle, and core are divided.⁸

Fracture Study

Fracture study looks at local separations or planes of discontinuity in geological formations. These can be things like joints or faults that split a rock into more than one piece. A common cause of fractures is stress on the strength of the rock. This stress can be natural or man-made. Rocks with many fractures are good aquifers and reservoirs for hydrocarbons, because fractures aid these fluids in moving through rock ⁴.

Geophysics

Geophysics is the study of the Earth with electrical, gravitational, magnetic, and seismic methods. Geophysics encompasses the study of the Earth's earthquakes, evolution, internal structure, material makeup, oceans, potential for environmental hazards, and other physical features².

Hydrology

In short, hydrology is the study of water. 70% of the Earth's surface is covered in water, and hydrologists study the distribution, movement, occurrence, and properties of that water, as well as how it interacts with the environment throughout the various phases of the water (hydrologic) cycle⁷.

Mineral Studies

Mineral studies, or mineralogy, is the study of chemistry, crystal structure, and physical properties of minerals. Mineralogists may look at how minerals originate and form, are classified, are distributed geographically, and are used ¹⁵.

Geo-mapping and Geomodeling

Geo-mapping is the visualization of the earth’s structure, drawn from information about nearby formations, drill samples, and seismic activity. It is used to locate oil and water and to predict earthquakes and volcanoes and allows one to have a better understanding of underlying rock. Geomodeling usually refers to a computer program used for geo-mapping, and there are several companies who develop these programs. Geomodeling can be used to create two or three dimensional visualizations¹⁴.

Research Questions

for Geosciences

• What are the interactions among the subsurface process?
• Can we reliably predict and control earthquakes?
• Are underground resources of drinking water safe and secure?
• Can we make the earth "transparent" and observe underground processess in action?

for Mining Engineering

• What are the mechanical properties of rock?
• How can technology lead to a safer underground?
• How does rock respond to human activity?
• How does water flow deep underground?
• What lies beneath the boreholes?

Experiments at DUSEL

DUGL

The Deep Underground Gravity Lab (DUGL), is part of DUSEL. The DUSEL site is attractive for this sub-lab due to the reduction of seismic noise, stable gravitational field, and stable environment that are a result of DUSEL’s depth. The DUGL has two goals:

Understand the structure of the seismic noise underground.
Estimate how large seismic array would be needed for active suppression of gravity gradient noise ⁹.

Homestake Seismometer Array
Each seismic station consists of a hut made of panels of rigid-foam. Inside this hut are the sensors, which need to be shielded from water and sound. The hut for the sensors also has an additional container that acts as a shield for the high-sensitivity seismometer, which must be guarded against sound and air currents. Beside the seismometer are sensors specialized to measure sound, temperature, barometric pressure, humidity, and the strength and direction of magnetic fields. A second hut contains a computer and power supply ⁶.

All of the seismic stations are remotely controlled from the DUGL, which is located inside the “Ross dry”³. Data from the seismic stations is sent to the lab on a regular basis via fiber link⁹. Approximately 2 GB of data is produced by each station every day. This data is eventually copied and sent to facilities at the California Institute of Technology (Caltech) to be stored and analyzed. Eventually, DUGL scientists would like to be able to access their laboratory computer system remotely, so that they and their colleagues can use the data no matter where they are. Each seismic station has a clock which is synchronized at the microsecond level. This creates an artificial antenna to measure vibrations in the rock³.

LIGO

The Laser Interferometer Gravitational Wave Observatory (LIGO), shares a base with the California Institute of Technology (Caltech) and the Massachusetts Institute of Technology (MIT). The goal of this experiment is to detect gravitational waves and subsequently control them in order to conduct further research. Eventually, LIGO scientists want to be able to use lasers that are a mile long to probe Homestake mine’s drifts and shafts in search of changes in the earth caused by gravitational waves¹⁰.

Gravitational waves are changes in the curvature of spacetime. A gravitational wave, in a general sense, a force field that moves at the speed of light and alters how far apart different masses are. In order to “see” gravitational waves, scientists must detect the changes in these distances. At DUSEL, LIGO has constructed antennas that measure the distance between suspended mirrors using laser light⁵¹⁰.

Ground vibrations, vibrations of the mirror’s surfaced caused by heat, variations in the laser light, and Newtonian noise. Of all of these, Newtonian noise is thought of as the most challenging when all is said and done. The team at Homestake's goal is to develop an improved understanding of Newtonian noise and from that develop techniques which lessen its negative effects when trying to detect gravitational waves⁵.

Because gravitational waves are so hard to measure, the LIGO team aims for the processes that are the most energetic in the universe. These include supernovae, the paths of neutron stars or binary black holes as they lose energy, and the Big Bang; however, even when scientists use such big engines as the producers of the gravitational waves they are detecting, the amount of movement that happens to the mirrors within one of the antennae is extremely small. Jan Harms, Angelo Sajeva, Riccardo Desalvo, and Vuk Mandic write of their efforts that “once we measure these waves, antennas around the world will open up a completely new window to our universe. This time we would not look out of the window, but hold our ears to the glass pane and listen to the death of stars and the birth of our observable universe”⁵.

Hydrology

Homestake Hydrostatic Water Level System
The Homestake Hydrostatic Water Level System consists of four arrays, two of which were installed on January 5, 2009. These two arrays are at the 2,000-foot level in Homestake Mine. Each array has 12 sensors, 3,200 feet of tubing, and 3,600 of phone cable to transfer data through. The “A array” is approximately 2,500 feet away from the Ross shaft while the “B array” is closer to it. The other two arrays will be installed at the 4,550 and 4,850-foot level ¹³.

When water has no outside force acting upon it, the surface will be level. This is the principal behind hydrostatic systems. The arrays are made up of tubes filled with water and connected to pools. Electric sensors monitor the tubes, transferring data over telephone and fiber-optic lines. The arrays are very sensitive and are capable of detect millionths of a meter changes in the water level. Each array covers 1,000 feet of tunnel and is expected to provide detailed data regarding how the ground moves due to crews pumping water out of Homestake Mine as well as seismic events, excavations, and earth tides. By comparing data from the different sensors, the researchers are able to see tilt and the direction of motion¹³.

Dr. Larry Stetler explains the HLS on the Sanford Laboratory's Youtube Channel.

Microclimate Network
The Microclimate Network consists of a series of climate stations. These stations are equipped with sensors that monitor climactic conditions in the mine and how they move during the process of pumping water out of the mine, changes in ventilation, and the increase in human activity. The sensors are able to project a 3-D view of these conditions for the benefit of researchers ¹².

Who's Doing It?

Further Reading

Geosciences

Cole, Joanna. The Magic School Bus: Inside the Earth. New York: Scholastic, 1997.
Children’s Nonfiction (2nd floor – Children’s Collection): 551 C689m, 1997

Faces of Earth. Prod. John Copeland. Narr. Maurice LaMarche. DVD Evergreen Films, 2008.
Nonfiction DVDs (1st floor – AV Collection): 550 FAC

Erickson, Jon. An Introduction to Fossils and Minerals: Seeking Clues to the Earth’s Past. New York: Facts on File, c2000.
Nonfiction (1st floor – Main Collection): 560 ERI
Reference (1st floor – Reference Collection): 560 ERI

Erickson, Jon. Rock Formations and Unusual Geologic Structures: Exploring the Earth’s Surface. New York: Facts on File, 2001.
Nonfiction (1st floor – Main Collection): 550 ERI

Kruckeberg, Arthur R. Geology and Plant Life: The Effects of Landforms and Rock Types on Plants. Seattle, WA: University of Washington Press, 2004.
Nonfiction (1st floor – Main Collection): 581.7 KRU

Marshak, Stephen. Earth: Portrait of a Planet. New York: Norton, 2001.
Nonfiction (1st floor – Main Collection): 550 M366

Morris, John David. The Geology Book. Green Forest, AR: Master Books, 2000.
Children’s Nonfiction (2nd floor – Children’s Collection): 550 MOR

Patent, Dorothy Hinshaw. Shaping the Earth. New York: Clarion Books, 2000.
Children’s Nonfiction (2nd floor – Children’s Collection): 500 P295s

Ross, Michael Elsohn. Earth Cycles. Brookfield, CN: Millbrook Press, 2001.
Children’s Nonfiction (2nd floor – Children’s Collection): 525 R825e

Squibs: Geology, Tectonics and Rocks. Vol. 9. DVD. Ignigte! Learning, 2005.
Children’s Nonfiction DVDs (2nd floor – Children’s AV Collection): 551 SQU

Mining Engineering

Rajaram, Vasudevan, Subijoy Dutta, and Krishna Parameswaran, Eds. Sustainable Mining Practices: a Global Perspective. New York: A. A. Balkema, 2005.
SDSMT's Deveraux Library - Main Book Collection: TD195.M5 S87 2005

United States Environmental Protection Agency. Identifying Opportunities for Methane Recovery at U.S. Coal Mines: Profiles of Selected Gassy Underground Coal Mines 1999-2003. Washington D.C.: U.S. Environmental Protection Agency, 2005.
SDSMT's Deveraux Library - GOV DOCS INTERNET: EP 1.2:M 56

Hartman, Howard L. and Jan M. Mutmansky. Introductory Mining Engineering. Hoboken, NJ: J. Wiley, 2002.
SDSMT's Deveraux Library - Main Book Collection: TN275 .H35 2002

Gertsch, Richard E. and Richard L. Bullock, Eds. Techniques in Underground Mining: Selctions from Underground Mining Methods Handbook. Littleton, CO: Society for Mining, Metallurgy, and Exploration, 1998.
SDSMT's Deveraux Library - Main Book Collection: TN275 .T33 1998

Mendecki, A. J., Ed. Seismic Monitoring in Mines. London: Chapman & Hall, 1997.
SDSMT's Deveraux Library - Main Book Collection: TN153. S45 1997

Brady, B. H. G. Rock Mechanics For Underground Mining. London: Chapman & Hall, 1993
SDSMT's Deveraux Library - Main Book Collection: TA706 .B73 1993

Hartman, Howard L., et al. Eds. SME Mining Engineering Handbook. Littleton, CO: Society for Mining, Metallurgy, and Exploration, 1992.
SDSMT's Deveraux Library - Reference (Lending): TN151 .S18 1992

Swakins, Frederick J. Metal Deposits in Relation to Plate Tectonics. Berlin, Springer-Verlag, 1990.
SDSMT's Deveraux Library - Main Book Collection: TN263 .S27 1990

Sastry, K. V. S., and M. C. Fuerstenau, Eds. Challenges in Mineral Processing: Proceeding a Symposium Honoring Douglas W. Fuerstenau on his 60th Birthday, Berkley, California, December 7-9, 1988. Littleton, CO: Society of Mining Engineers, 1989.
SDSMT's Deveraux Library - Main Book Collection: TN501 .C43 1989

Media

External Links

• ipl2 (Internet Public Library + Librarians' Internet Index) resources for Earth Sciences
• United States Geological Survey
• Geoscience Information Society
• Mining Engineering Magazine