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Lineations And Structural Mapping Of Io's Paterae And Mountains: Implications For Internal Stresses, Alexandra Anne Ahern
Lineations And Structural Mapping Of Io's Paterae And Mountains: Implications For Internal Stresses, Alexandra Anne Ahern
Theses and Dissertations
Io, the most volcanically active body in the solar system, also has some of the tallest and steepest mountains. The mountains seem to be tectonic in origin, yet the methods of their formation have not been decisively constrained and their associations with volcanic paterae are yet unclear. We have compiled global spatial statistics on mountain dimensions and orientations, lineations attributed to structures, straight patera margins, and patera dimensions in order to better define their genetic relationships and the mechanisms forming each type of feature. Additionally, we have produced 4 regional structural maps of mountain complexes and have proposed tectonic histories. …
Tectonics Of Saturn's Moon Titan And Tsunami Modeling Of The 1629 Mega-Thrust Earthquake In Eastern Indonesia, Yung-Chun Liu
Tectonics Of Saturn's Moon Titan And Tsunami Modeling Of The 1629 Mega-Thrust Earthquake In Eastern Indonesia, Yung-Chun Liu
Theses and Dissertations
Chapter 1-2:The Cassini RADAR mapper has imaged elevated blocks and mountains on Titan we term ‘ridges’. Two unresolved problems regarding Titan's surface are still debated: what is the origin of its ridges and was there tectonic activity on Titan? To understand the processes that produced the ridges, in this study, (1) we analyze the distribution and orientation of ridges through systematic geomorphologic mapping and (2) we compare the location of the ridges to a new global topographic map to explore the correlation between elevation and ridges and the implications for Titan's surface evolution. Globally, the orientation of ridges is nearly …
The Rice Bay And Northeast Bay Gneiss Domes: A Kinematic Study Of Competent Rock Bodies In The Rainy Lake Region Of Ontario, Canada, Jane Block
Theses and Dissertations
The Rice Bay and Northeast Bay gneiss domes (RBD and NEBD) are two tonalitic rock units located in the Archean Rainy Lake zone of the Superior Province. The Rainy Lake zone acts as a boundary between two subprovinces, accommodating transpression, significant shortening and dextral motion in its lithologic assemblage. This study contributes to understanding how deformation is partitioned in heterogeneous terranes, and also demonstrates a practical method of kinematic analysis. Foliations, lineations, shear zones, tension gashes, quartz veins, mafic enclaves, and folded and boudined veins were all utilized in the kinematic analysis. Foliation orientations in both domes are consistent with …
Evolution And Emergence Of The Hinterland In The Active Banda Arc-Continent Collision: Insights From The Metamorphic Rocks And Coral Terraces Of Kisar, Indonesia, Jonathan R. Major
Evolution And Emergence Of The Hinterland In The Active Banda Arc-Continent Collision: Insights From The Metamorphic Rocks And Coral Terraces Of Kisar, Indonesia, Jonathan R. Major
Theses and Dissertations
Coral terrace surveys and U-series ages of coral and mollusk shells yield a surface uplift rate of ~0.6 m/ka for Kisar Island. The small island is located NE of Timor in the active Banda Arc of Indonesia. Based on this rate, Kisar first emerged from the ocean as recently as ~450 ka. Terrace surveys show warping that follows a pattern of east-west striking folds, which are along strike of thrust-related folds of similar wavelength imaged by a seismic reflection profile just offshore. This deformation shows that the emergence of Kisar can be attributed to forearc closure along the south-dipping Kisar …
Origin And Tectonic Evolution Of Gondwana Sequence Units Accreted To The Banda Arc: A Structural Transect Through Central East Timor, Elizabeth Anick Zobell
Origin And Tectonic Evolution Of Gondwana Sequence Units Accreted To The Banda Arc: A Structural Transect Through Central East Timor, Elizabeth Anick Zobell
Theses and Dissertations
Petrographic and age analysis of sandstones, detailed structural analysis and gravity modeling were conducted to investigate the origin of the Gondwana Sequence in the Timor Region, and to better constrain the tectonic evolution of the active Banda Arc. Our field studies and U/Pb zircon age analysis helped assign most units to either Asian or Australian affinity. Detrital zircon from uplifted Banda forearc units (Asian affinity) have U/Pb ages as young as 80 Ma (Standley and Harris, in press). In contrast, analysis of detrital zircon from Gondwana Sequence sandstones accreted to the Banda Arc from Savu to East Timor are no …
Banda Forearc Metamorphic Rocks Accreted To The Australian Continental Margin: Detailed Analysis Of The Lolotoi Complex Of East Timor, Carl Eldon Standley
Banda Forearc Metamorphic Rocks Accreted To The Australian Continental Margin: Detailed Analysis Of The Lolotoi Complex Of East Timor, Carl Eldon Standley
Theses and Dissertations
Petrologic, structural and age investigations of the Lolotoi Complex of East Timor indicate that it is part of a group of thin metamorphic klippen found throughout the region that were detached from the Banda forearc and accreted to the NW Australian continental margin during Late Miocene to Present arc-continent collision. Metamorphic rock types are dominated by (in order of greatest to least abundance), greenschist, graphitic phyllite, quartz-mica schist, amphibolite and pelitic schist. Mineral, whole rock, and trace element geochemical analyses of metabasites indicate that protolith compositions are consistent with tholeiitic basalt and basaltic andesite with mixed MORB and oceanic arc …
Gps Velocity Field In The Transition From Subduction To Collision Of The Eastern Sunda And Banda Arcs, Indonesia, Hendro Nugroho
Gps Velocity Field In The Transition From Subduction To Collision Of The Eastern Sunda And Banda Arcs, Indonesia, Hendro Nugroho
Theses and Dissertations
Campaign GPS measurements during 2001-2003 in the transition between subduction and collision of the Banda arc reveal how strain is partitioned away from the trench and distributed to other parts of the arc-trench system. Genrich, et. al. (1996) conducted a GPS campaign (1992-1994) throughout the Eastern Sunda and Banda arcs that demonstrated partial accretion of the arc to the Australian plate. We reoccupied many of the sites from this earlier study and 7 additional stations, 3 of which are new benchmarks. Our study shortened many baselines and extended the observation epoch to ten years for many key stations. The resulting …