Fall 2018 Seminars
|August 27, 2018||Numerical Simulations of Coupled Aero-Thermodynamic Systems Based on the Lattice-Boltzmann Method||Aleksandra Pachalieva|
|September 3, 2018||<Labor Day>|
|September 10, 2018||Helical Interactions of DNA||Aaron Wynveen|
|September 17, 2018||mK to km: How Millikelvin Physics is Reused to Explore the Earth Kilometers Below the Surface||Robert Kleinberg|
|September 24, 2018|
|October 1, 2018|
|October 8, 2018|
|October 15, 2018|
|October 22, 2018|
|October 29, 2018|
November 5, 2018
|November 12, 2018||<Veterans Day>|
|November 19, 2018|
|November 26, 2018||<TBA>||Andrew B. Croll|
December 3, 2018
|December 10,2018||<Finals Week>|
mK to km: How Millikelvin Physics is Reused to Explore the Earth Kilometers Below the Surface
Dr. Robert L. Kleinberg
American Physical Society Distinguished Lecturer
on the Applications of Physics,
Institute for Sustainable Energy
Refreshments at 2:30
Monday September 17, 3:00-4:00pm,
221 South Engineering
investigations of the superfluid phases of liquid helium-3 would seem to have little application to the study of rock formations thousands of meters below the surface of the earth. However, the physicist’s tool box is versatile, and techniques used in one field of study can be reused, with appropriate adaptation, in very different circumstances.
The temperature of liquid helium-3 in the millikelvin range can be measured using an unbalanced-secondary mutual inductance coil set designed to monitor the magnetic susceptibility of a paramagnetic salt. The loss signal is discarded by phase sensitive detection. Now consider the task of measuring the electrical conductivity, at centimeter scale, of the earth surrounding a borehole. Turn the mutual inductance coil set inside out, with secondary coils arranged to be unbalanced with respect to the rock wall. Instead of discarding the loss signal, use it to measure conductivity. A sensor based on this principle has been implemented in a widely deployed borehole geophysical instrument, used to estimate the prevailing direction of the wind millions of years ago, or to decide where to drill the next well in an oilfield.
Nuclear magnetic resonance may seem a very improbable measurement of the rock surrounding a borehole. Conventionally, we place the sample (which might be a human being) inside the NMR apparatus. In borehole deployment, the instrument is placed inside sample, the temperature is as high as 175C, pressure ranges to 140 MPa, and measurements must be made while moving at 10 cm/s. Apparatus with these specifications have been deployed worldwide, and are used to measure a number of rock properties, including the distribution of the sizes of pores in sedimentary rock, and the viscosity of oil found therein. They have also been used for geological and oceanographic studies in northern Alaska, and at the seafloor offshore Monterey, California.
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