Understanding our dynamic landscape gives us great insight into the past and the ability to make educated predictions of possible future events of the world we live in today. The Mackenzie basin is a wide valley basin containing three glacial lakes which have the potential to provide understanding into the glacial, tectonic and climate history of the Southern hemisphere and in particular, New Zealand. The South Island of New Zealand is characterised by oblique continental collision of the Australian and Pacific tectonic plates, forming the dominant Southern Alps. The plate boundary is known as the Alpine fault and attention has often be associated with motion on the western side of the Alps, but more recently studies have been focussing on the eastern side. Upton1 writes in the New Zealand Journal of Geology and Geophysics about her research, which mapped the Irishman Creek fault (ICF) and the Forest Creek Fault (FCF) into the lake basin of Lake Tekapo. It has been inferred of the existence of the Tekapo River fault (a north-south structure), from seismic data and exposed geology. (Long ’03)
The ICF is a large feature in the Mackenzie basin and runs along strike to the Alpine Fault. This fault has uplifted the Old man range and is likely to be a part of a broader zone of deformation, the Irishman Creek fault zone (Fox ’87, Cox & Barrell ’07). In the last 5000 years, an interval for reoccurring major events on the ICF of 1290±90yr was determined from dating on scree slopes along the fault trace ( McSaveney ’91).
Initial seismic surveys of Lake Tekapo were conducted by Pickrill and Irwin in ’83. Seismic penetration was approximately 25m below the lake bottom. They classified the sediments, which were sourced from the Godley rive...
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...ation of basement highs, disturbed reflections and orientations parallel to the ICF suggest that we are seeing a continuation of the fault within the lake basin on lines 4,5,6 (basement high west of motuariki basin on L5, two dipping reflector b8&9, apparent dip of 30E )
2)Occur along strike of FCF, suggesting that the basement highs & lake floor features have resulted from movement along this structure (three lake floor highs overlying basement highs and folded sediments)
Topographic highs in a tectonically and glacially active regions may form constructionally by uplift on a fault , or as ROCHES MOUTONNEES by glacial erosion or it may reflect both processes. Upton proposed that these bedrock highs beneath the subsurface of Lake Tekapo are fault-controlled but are being eroded down c.100 ka by glaciers from the Southern Alps contributes to the Roches Moutonnees.
Marshak, S. (2009) Essentials of Geology, 3rd ed. New York: W.W. Norton & Company, ch. 11, p. 298-320.
The third alluvial deposition consists of sand, silt and minor inter-bedded gravel, and again indicates Brimbank Park’s changing geology over time. (Geological map of Victoria, 1973). These deposits, as well as a nearby fault suggest volcanic activity 5-1.6 million years ago, which explains the olivine basalt (fig. 2) deposits which date back to to the Silurian and Tertiary period.
Earthquakes are a natural part of the Earth’s evolution. Scientific evidence leads many geologists to believe that all of the land on Earth was at one point in time connected. Because of plate tectonic movements or earthquakes, continental drift occurred separating the one massive piece of land in to the seven major continents today. Further evidence supports this theory, starting with the Mid-Atlantic ridge, a large mass of plate tectonics, which are increasing the size of the Atlantic Ocean while shrinking the Pacific. Some scientists believe that the major plate moveme...
"Mechanics of Graben Evolution in Canyonlands National Park, Utah." Geological Society of America Bulletin. Web. 05 Dec. 2011. .
The central belt of the Franciscan Complex represents older and more metamorphosed units of rock best characterized as a melange. Blocks of graywacke, greenstone, chert, limestone, and blueschists are sheared and thrust upon one another in a choatic mix (Isozaki and Blake, 1994). In contrast to the coastal belt, metamorphism is higher in grade here and dominated by pumpellyite which formed within the matrix of graywacke (Hagstrum and Murchey, 1993). The mixing of these units makes a stratigraphic subdivision difficult but analysis of the graywacke slabs indicates that the depositional environment was also deep sea, near to the continent. Turbidity currents in this environment deposited much of the sediment in both the coastal and central belts.
At the end of the last ice age windblown silt covered the lava and basalt deposits. This silt would go on to create the fertile rolling hills of the Palouse. This soil is more than a hundred feet deep in places. Soon, enough time passed for vegetation to take place and more soil started to form.1 The lava flows would end up damming streams flowing from the mountains; in turn forming the current lakes of the region. Layered between the flows of basalt are sand and gravel deposits that washed down from mountains.1
In conclusion these various factors explain the theory that Kaibab Plateau is actually much older than the Colorado River and that the lake overflow theory best explains the multiple processes that contributed to this natural features current landscape. Lake Bidahochi would have flooded from time to time and combined with the lowest elevation on the Kaibab Plateau, the incision would have started. Considering major rivers have the capability to erode materials such as basaltic bedrock, going through the Kaibab Plateau would have proven possible. With circular scarps retreating from the plateau, the meandering of both rivers are explained and the presence of Colorado River limestone in a sequence of ancient basins today prove the river was younger than the uplift that took place in this region.
Hess, D., McKnight, T. L., & Tasa, D. (2011). McKnight's physical geography (Custom ed. for California State University, Northridge ; 2nd Calif. ed.). New York: Learning Solutions.
Plummer, C.C., McGeary, D., and Carlson, D.H., 2003, Physical geology (10th Ed.): McGraw-Hill, Boston, 580 p.
Tarbuck E., Lutgens F., Tasa D., 2014, An Introduction to Physical Geology, 5th Ed, Pearson Education, Upper Saddle River, New Jersey.
Stone Mountain rises in sharp contrast to the surrounding flat, rolling landscape creating a geomorphic monadnock. Geologists appear to have consensus of the volcanic origins and underground formation of t...
First you might need to know definition of tectonics. It is a theory in geology. The lithosphere of the Earth is divided into a small number of plates which float on and travel independently over the mantle and much of the Earth’s seismic activity occurs at the boundaries of these plates. That is the official definition of Plate tectonics. secondly, this plate covers many parts of continents. plate boundaries don’t go according to Continents boundaries, they make their own boundaries. The North American plat...
Churcher, C. S. & Wilson. M. (1979). Journal of Paleontology. Michigan: SEPM Society for Sedimentary Geology
Waltham, Tony. "Sinking cities." Geology Today 18.3 (2002): 95+. Academic OneFile. Web. 08 Feb. 2014.
inferred for the reservoir (4). The magma ascent to the surface occurred through a conduit of possibly 70 to 100 m in diameter (5). A thermal model predicts that such a reservoir should contain a core of partially molten magma (6) that can be detected by high-resolution seismic tomography.