Show simple item record

dc.contributor.advisorLi, Yaoguo
dc.contributor.authorParkan, Nil
dc.date.accessioned2021-09-13T10:20:46Z
dc.date.accessioned2022-02-03T13:23:28Z
dc.date.available2021-09-13T10:20:46Z
dc.date.available2022-02-03T13:23:28Z
dc.date.issued2021
dc.identifierParkan_mines_0052N_12261.pdf
dc.identifierT 9218
dc.identifier.urihttps://hdl.handle.net/11124/176496
dc.descriptionIncludes bibliographical references.
dc.description2021 Summer.
dc.description.abstractGeological units typically contain both induced and remanent magnetization. The vector sumof the two components forms the total magnetization to which magnetic data is sensitive. The induced component depends on the susceptibility and current geomagnetic field, whereas the remanent magnetization depends upon the formation history of the geological units. Remanent magnetization, therefore, carries information about the formation process and subsequent structural movement of these units. For this reason, identifying remanent magnetization from geophysical magnetic data could yield additional information which would otherwise not be available for geological interpretation. I investigate an approach for separating remanent magnetization from the induced component in the total magnetization recovered from a 3D magnetic inversion. Assuming the known total magnetization, I allowed for a range of susceptibility values, and I tested the effects of the assumed probability distribution of the susceptibility onto the resulting distributions of the observed remanent magnetization. Given the importance of remanence in geophysical interpretation, I further examine the direction of the extracted remanent magnetization. This was accomplished by using Fisher statistics and the Parzen windows method to estimate the probability density distribution of the remanent magnetization direction. I build two synthetic examples that have two source bodies that went through a structural deformation and rotation to test our analyses. The two bodies are offset and rotated relative to each other, so the rotated object’s remanent magnetization will be different even though induced magnetization stays the same for each body. By using remanent magnetization extracted from the inverted total magnetization, I apply the methodology we developed for each of the blocks separately after taking the average to decrease the directional variability within the blocks. As a result, I estimate a remanent magnetization average direction for the unrotated and rotated objects in the model in order to recover the two units’ relative rotation angle. This study offers a new approach to understanding how to extract and quantify the remanent magnetization magnitudes and directions for revealing the rotation angle where the deformation is present in the study area. Having only statistical susceptibility information available from petrophysical data, I present a preferable alternative in real-world problems with a reliable angle recovery.
dc.format.mediumborn digital
dc.format.mediummasters theses
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado School of Mines. Arthur Lakes Library
dc.relation.ispartof2021 - Mines Theses & Dissertations
dc.rightsCopyright of the original work is retained by the author.
dc.subjectParzen window
dc.subjectstatistics
dc.subjectremanent magnetization
dc.subjectFisher distribution
dc.titleSeparation of induced and remanent magnetization by using statistical susceptibility data
dc.typeText
dc.contributor.committeememberKrahenbuhl, Richard A.
dc.contributor.committeememberTenorio, Luis
dc.contributor.committeememberSwidinsky, Andrei
thesis.degree.nameMaster of Science (M.S.)
thesis.degree.levelMasters
thesis.degree.disciplineGeophysics
thesis.degree.grantorColorado School of Mines


Files in this item

Thumbnail
Name:
Parkan_mines_0052N_12261.pdf
Size:
5.172Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record