Physical Sciences and Mathematics Commons^™

Structural And Kinematic Investigation Of The Dadeville Complex-Brevard Zone Contact (Southern Appalachians): Polyphase Emplacement Of An Allochthonous Terrane On The Laurentian Margin, Andrew Williams

Master's Theses

The Dadeville Complex (DC) lies in the Inner Piedmont of eastern Alabama and western Georgia. The DC formed as a volcanic island arc during the Taconic orogeny (Ordovician Period) and was accreted onto Laurentia during the Acadian orogeny (Devonian-Mississippian Periods); however, the mechanism and role of accretion during the Acadian orogeny is not well constrained. Three proposed emplacement mechanisms for the DC include: (1) orogen-perpendicular translation; (2) orogen-parallel translation; (3) orogenic channel flow.

Today, the DC is a major (over 100 kilometers long) allochthonous terrane composed mostly of meta-igneous rocks. This study investigated structural fabrics and kinematic indicators in the …

Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black

Master's Theses

The Appalachian Mountains have a complex geologic history spanning three orogenic periods, the Taconic, the Acadian/Neoacadian, and Alleghanian orogenies. The Inner Piedmont of the Appalachian Mountains within Alabama contains two distinct lithologic complexes, the Dadeville Complex, and the Opelika Complex separated by the Stonewall Line. These complexes were formed during an arc-back arc fringing system during the Taconic orogeny and emplaced and recorded peak metamorphism during the Acadian orogeny.

The Dadeville Complex is an allochthonous arc terrain built on extended Laurentian crust. The mode of transportation and accretion after formation is not well understood, which has implications for the role …

Investigating The Timing Of Initial Louann Salt Flow And Its Relationship With The Gilbertown Fault Zone, Southwest Alabama, Avery Rosenbalm

Master's Theses

The Mesozoic Louann Salt extends through the northern GOM, extending onshore from eastern Texas to western Alabama and Florida. Along the landward terminus of the salt is a system of peripheral faults, including the Gilbertown Fault Zone bordering the Mississippi Interior Salt Basin to the north and east. This study sought to constrain the timing of fault movement and determine its relationship to the baswinward evacuation of Louann Salt through the use of a 3D seismic survey and well logs. By mapping Mesozoic formations and the peripheral fault system, lateral changes in formation thickness were used to generate fault expansion …

Sediment Provenance Of Tsunami Deposits: Implications For Assessing The Relative Intensity Of Paleotsunamis From The Sendai Coastline Of Japan, Tiffany Otai

Master's Theses

The 2011 Tohoku tsunami impacted the northeastern coast of Japan and caused unexpected damages due to the underestimation of this type of hazard. Of particular importance is the fact that geologic evidence for a predecessor event, the Jogan tsunami (CE 869), could have forecasted the severity of the 2011 Tohoku event. While the timing of tsunamis is important for effective hazard mitigation, outside of the 2011 Tohoku event, the intensity of past tsunamis remains unclear. To understand paleotsunami intensity, it is important to document characteristics of modern analogues like the 2011 event. This study utilizes surface distributions of foraminifera from …

Structural Synthesis And Spatial Distribution Of A 335 Ma Igneous Suite From The Eastern Blue Ridge, Alabama Appalachians, Avery Rosenbalm

Honors Theses

The Appalachian range was formed by three orogenies, the most recent being the Alleghanian beginning at ~330 Ma. A small pluton outcropping along Highway 280 near Alexander City, AL, called the 280 granodiorite, has been dated at ~335 Ma and intrudes the Devonian Elkahatchee Quartz Diorite (EQD). While little work has been done on the intrusion, it is significant because of its age: all deformation of the intrusion should be related to the Alleghanian orogeny, while most other bodies in the region exhibit significant overprinting due to previous successive orogenies. The pluton was mapped constraining the geographic extent, which is …

The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler

Master's Theses

Fe-Ti oxides are important components of oceanic core complexes (OCC) formed at slow-spreading mid-ocean ridges since Fe-Ti oxides are more susceptible to crystal-plastic deformation than silicate minerals. This study investigated the predicted relationship between the presence and concentration of Fe-Ti oxides and the presence and intensity of crystal-plastic deformation in gabbroic samples from Atlantis Bank, Southwest Indian Ridge (SWIR). Atlantis Bank is an oceanic core complex that formed through the exhumation of lower oceanic crust along a detachment fault. OCCs form along slow-spreading ridges and are characterized by the complex interactions between magmatism and lithospheric extension, thus making these complexes …