Written Assignment #3
The Hood is Real
Damian McElroy
Word Count: 1525
Due: Nov 18, 2014

Introduction
The High Cascade volcanoes are comprised with many volcanoes formed by basaltic eruptions many years ago. More specifically this research report will be designated to the Mt. Hood region seen in figure (1). Research from articles will be provided with references of their origins and give a clear description of the “Hood”, as well as any dangers it may present to populations near by if it were to become unstable. The research comprised within this report is specific and done so with the use of Google Earth images and articles designated to the specific Mt. Hood area; with this research, a hazard assessment and a reliable research station location will be clearly justified and outlined respectively.

Description
Mt. Hood is a stratovolcano located 45° 21'58.83"N, 121° 41' 43.51"W, has a diameter of 8.83km-10km (This will vary depending on where the diameter is measured from) and a maximum height of 3426m. The elevation profile can be seen in Figure (2), which distinctively justifies the reason for Mt. Hood being classified as a stratovolcano, due to the very steep slope and maximum height of the mountain. Mount Hood, Oregon's highest peak forms a prominent backdrop to the state's largest city, Portland (Smithsonian Institution, 2013). The glacially eroded volcano has been subject to four major eruptive periods during the past 15,000 years (Smithsonian Institution, 2013). “The last three occurred within the past 1800 years from vents high on the SW flank and produced deposits that were distributed primarily to the south and west along the Sandy and Zigzag rivers” (Smithsonian Institution, 2013). The most recent eruptive period took place 170-220 years ago, when growth of the Crater Rock lava dome was accompanied by pyroclastic flows and lahars down the White and Sandy rivers (Smithsonian Institution, 2013).
The High Cascade lavas of the Mt. Hood area were erupted producing scattered andesite volcanoes close by (Wise, 1968). Epiclastic and pyroclastic debris were shed from the centers of activity into basins along either side of the Cascade mountain belt (Wise, 1968). The Mt. Hood volcano formed many years ago in the late Pleistocene time. The majority of it is composed of olivine, pyroxene, hornblende-dacite lavas and pyroclastic debris (Wise, 1968). Justified by figure (1), it is evident that the volcano recently has had a pyroclastic flow on the south face of the mountain, which is a valid assumption due to the fact there is valley with no vegetation growing. As well, there is little vegetation and plains of pumice on the NE side of the volcano, suggesting that an earlier pyroclastic flow and eruption had occurred but has already become fertile land.

Hazard Assessment
During the formation, the Mt. Hood region had very low elevation and low relief (Williams, etal. 1982). Many basaltic flows flooded the area from the Cascade Range which stretches across the Pacific margin of North America flooded the area, although none of the eruptions were centered at Mt. Hood (Williams, et al. 1982). The inferred magnetizations of Mt. Hood and its surrounding cones suggest that they are predominantly basaltic composition (Williams, etal. 1982). The most recent activity in the Mt. Hood region is approximately 200 years old (Williams, etal. 1982). The event (eruption) produced the Crater Rock dacite plug dome, the Old Main Flat mudflow, and large ash deposits high on the south side of the mountain (Williams, et al. 1982). Through the Google Earth satellite image seen in Figure (3), it is evident that north of Mt. Hood there is less young volcanism and the volcanism is predominantly andesitic (light color). The cone of Mt. Hood consists of at least 70% lava flows; the rest is pyroclastic debris (Williams, et al. 1982). Therefore it would make sense that in a large-scale rainfall the slopes would become highly unstable, causing debris flows with unknown size and destructive forces.

The populations nearby Mt. Hood will vary depending on the time of year. This is due to the recreational ski hill located on the south side of the mountain and can be seen in figure 5. Populated areas such as: Mt. Hood Village and Rhododendron located west of Mt. Hood summit also seen in figure (4), and a government camp located SW of the Mt. Hood summit seen in figure (5) are populated areas 100% of the time from year to year. Low populated farmland and farmhouses NE of Mt. Hood seen in figure (3) are also within a possible danger zone if the volcano ever were to spontaneously react. The village west of Mt. Hood rests in low elevation at the bottom of a valley stemming from Mt. Hood. This may be a possible threat to the population in the event of a heavy rainfall, which in return will result in landslides that would funnel directly to the village.

Another large hazard in the region is a dam located N of Mt. Hood at Laurance Lake seen in figure (6) which is easily reachable by a pyroclastic flow or a landslide from the volcano. If the dam was breached, any life below the dam and close to the river will be in danger until the breached water has passed through Hood River located N of the dam clearly depicted in figure (7). This would most likely cause a great deal of damage to river systems in the area with contaminants from minerals, erosion and overflow.

Research Station Location
After assessing the possible hazards of the volcano and further analyzing the Mt. Hood region and its local terrain, a pinned point seen in figure 8 identifies a promising location for a research station. The location of the station at Latitude 45°18'16.28"N and Longitude 121°38'13.77"W is easily accessible by a side road from highway 35. With road access this will allow for quick and easy transportation to multiple mountain faces if needed, also making the cost of the research station more reasonable. The most recent activity is on the east or north side of the volcano seen in figure 1. The location of the research station of the east side of the volcano will allow for a better standpoint on the more recent activity in the Mt. Hood region.
The location of the research station will not only be easily accessible and reasonably priced but will also remain out of harms way primarily due to its high elevation. Having a research station in line of a valley could potentially threaten the lives of the people on site. The station has to be far enough away so that no possible threats from landslides are seen. With the use of Google maps, this eliminates any possible locations within a 3.5-mile radius from the peak of the mountain.

Conclusion
The High Cascade volcanoes stretch across the Pacific margin of North America and consist of several basaltic-formed volcanoes where very few of which come close to the size of Mt. Hood. This research report was specific to the Mt. Hood region and was laid out to give a clear description of the “Hood”, as well as any dangers it may present to populations near by if it were to become unstable. The research comprised within this report was specifically focused towards finding a safe and efficient research station location, and done so with the use of Google Earth images and articles designated to the specific Mt. hood area. The location of this research station was supported by a detailed hazard assessment of the volcano, which made it evident that if the “Hood” ever erupted, the severity of the damage is unpredictable to the surrounding populated areas. All that can be done is more research on the stratovolcano to hopefully predict the occurrence of the next major eruption if any at all.

Figure (1)

Google Earth 10.10.2014. (August 18, 2010). Mt. Hood. 45° 21'58.83"N, 121° 41' 43.51"W, Eye alt 20.98 km. Landsat. www.google.com/earth/index.html (Accessed October10, 2014)

Figure (2)

Google Earth 10.10.2014. (August 18, 2010). Mt. Hood. 45° 22'18.36"N, 121° 42' 03.93"W, Eye alt 17.30 km. Elevation Profile. www.google.com/earth/index.html (Accessed October10, 2014)

Figure (3)

Google Earth 10,27,2014. (August 18, 2010). Mt. Hood. 45°25’52.31”N 121°41’24.73”W eye alt 32.33km. Landsat. www.google.com/earth/index.html (Accessed October 27, 2014)

Figure (4)

Google Earth 10,27,2014. (August 18, 2010). Mt. Hood. 45°21’39.25”N 121°53’41.47”W eye alt 23.56km. Landsat. www.google.com/earth/index.html (Accessed October 27, 2014)
Figure (5)

Google Earth 10,27,2014. (August 18, 2010). Mt. Hood. 45°18’55.76”N 121°44’26.06”W eye alt 10.38km. Landsat. www.google.com/earth/index.html (Accessed October 27, 2014)

Figure (6)

Google Earth 10,27,2014. (August 18, 2010). Mt. Hood. 45°27’31.92”N 121°39’19.15”W eye alt 4.56km. Landsat. www.google.com/earth/index.html (Accessed October 27, 2014)

Figure (7)

Google Earth 10,27,2014. (August 18, 2010). Mt. Hood. 45°35’01.39”N 121°35’07.06”W eye alt 16.17km. Landsat. www.google.com/earth/index.html (Accessed October 27, 2014)

Figure (8)

Google Earth 11,13,2014. (August 18, 2010). Mt. Hood. 45°20’19.96”N 121°40’40.19”W eye alt 13.31km. Landsat. www.google.com/earth/index.html (Accessed November 13, 2014)

References
Hans D. Ackermann, Marvin H. Beeson, Donald A. Hull, David L. Williams (April 10, 1982) The Mt. Hood Region: Volcanic History, Structure, and Geothermal Energy Potential. Journal of Geophysical Research, Vol. 87, No. B4, Pages 2767-2781.
William S. Wise (September 3, 1968) Geology and Petrology of the Mt. Hood Area: A Study of High Cascade Volcanism, http://gsabulletin.gsapubs.org/content/80/6/969.short
Smithsonian Institution, National Museum of Natural History, global Volcanism Program (2013). http://www.volcano.si.edu/volcano.cfm?vn=322010