Extension between Major Faults, Central Oregon Basin and Range

• Main Author: Treerotchananon, Anuwat, 1979-
• Language: en_US
• Published: University of Oregon 2010
• Subjects: Faults (Geology) > Oregon > Summer Lake Watershed
• Online Access: http://hdl.handle.net/1794/10082

xi, 60 p. : ill. (some col.), maps (some col.). A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. === I present an alternative approach to determine the magnitude and direction of extension in the Basin and Range Province at the north end of Summer Lake basin using GIS techniques. Offset across 161 faults and tilting of 56 fault blocks were estimated to calculate extension as a function of azimuth in this area. The orientation of a representative set of slickenlines was collected in the field to assign average values for the GIS analysis. Azimuthal variation of extension is consistent with a strain ellipse indicating plane strain with extension of 1.5 to 5.5 percent along the maximum extension direction of N75E and no extension along the minimum N15W axis. Blocks tilt on average 60° from the maximum extension direction, suggesting the underlying detachment dips -N15E. This technique allows strain associated with the numerous small faults to be added to the sparse large faults for a complete regional analysis. === Committee in Charge: Dr. Ray Weldon, Chair; Dr. David Schmidt; Dr. Marli Miller