Landscape Features Resulting from Stream Processes
The topographic map of Waterville accurately depicts both the local surface features and the large-scale tectonic features that form the region. On the topographic map, one can trace the regional landscape features represented by those that directly arose due to river processes- channels, floodplains, valleys, and oxbow lakes. Meanders form when the outer banks of a stream erode over time, causing the channel to bend (Gastaldo et al., 2020). In this area, the streams also form a floodplain, a flat lowland near a frequently flooded stream (Lehnigk & Larsen, 2022). The map shows several winding canals cut, eventually turning into an oxbow lake.
Another feature of the landscape that can be identified on a topographic map is the formation of a V-shaped valley. It occurs as a result of active erosion of the bottom and banks, deepening the riverbed. The stream carries much debris that scratches, cuts, and erases the rocks that make up the bed of the river and the banks (Marshak, 2019).
Stream Floodplain Erosion and Potential Impact on Surface Development
A floodplain is the lowest vegetated part of the bottom of a river valley, which is completely or partially flooded during high waters and floods. The floodplain originates from the erosion-accumulation activity of the river flow (Gastaldo et al., 2020). When the floodplains are filled with water, the river’s flow rate slows down due to friction with the rock and the earth, which causes sediment.
It could increase the likelihood of flooding in the area, which would have catastrophic consequences for people and property due to landscape changes (Lehnigg & Larsen, 2022). Area A is at the greatest risk, as it is located below the mouths of the streams and the Mackenzie River. In the event of a flood, the river will overflow its banks and flood the area faster, which will have a negative impact on the area. In addition, the location of area A below an elevated mountain/hillside puts this at risk of landslides.
Tectonic Elements Present in the Surface Landscape
The topographic map of Waterville shows not only the features of the surface topography but also the main tectonic elements. One of the geological features is a fault line that cuts across the area from Camp Creek Cemetery to the southeast beyond the Mackenzie River. When tectonic plates move, they leave behind fault lines that can be epicenters for earthquakes (Hicks & Evans, 2022).
According to the data provided, activity was recorded in the area, but this did not cause any noticeable changes in the landscape (Southern New Hampshire University, n.d.). Waterville is located in the Cascadia subduction zone, where two tectonic plates meet. If active, these plates can contribute to volcanic eruptions (Marshak, 2019). However, no eruptions have been recorded in the last 630 years (Southern New Hampshire University, n.d.).
Historical Data on Tectonic Features and Potential Hazards
Several earthquakes have been recorded in the Waterville area due to its proximity to several active fault lines (Southern New Hampshire University, n.d.). Records of seismic and volcanic activity can provide insight into the level of risk in a region (Hicks & Evans, 2022). For example, records of past earthquakes can be used to predict future seismic activity. Although no earthquakes have been recorded in the last 85 years, the area is potentially active (Southern New Hampshire University, n.d.). An earthquake can cause severe damage, but the consequences will generally depend on the causes that led to it.
Potential Impact on the Proposed Development
The potential impact of the tectonic features of the area on the planned construction cannot be discounted. Earthquakes and lava flows can endanger life and property and damage ecosystems (Hicks & Evans, 2022). Potential hazards affecting the proposed development include the tectonic features of the landscape surface. It is possible to extrapolate the potential impact of tectonic activity in the area from earthquakes and volcanic records.
References
Gastaldo, R. A., Kus, K., Tabor, N., & Neveling, J. (2020). Calcic vertisols in the upper deptocephalus assemblage zone, Balfour formation, Baroo basin, South Africa: Implications for the late Permian climate. Journal of Sedimentary Research, 90(6), 609-628. Web.
Hicks, J. L., & Evans, J. E. (2022). Oxbow lakes as geological archives of historical changes in channel substrate, Swan Creek, Toledo, Ohio (USA). Open Journal of Modern Hydrology, 12(2), 32–54. Web.
Lehnigk, K. E., & Larsen, I. J. (2022). Pleistocene megaflood discharge in Grand Coulee, channeled scabland, USA. Journal of Geophysical Research: Earth Surface, 127(1), e2021JF006135. Web.
Marshak, S. (2019). Essentials of geology. W.W. Norton & Company.
Southern New Hampshire University. (n.d.). PHY 103 final project historical data.