Map Of The Ocean Floor Showing Plate Boundaries

Attached is a map of the ocean floor. It shows plate boundaries and F

Attached is a map of the ocean floor. It shows plate boundaries and features of the continental margin. All that you have to do is drag the letters from below and place them where they belong. You can open the attached tutorial to learn how to add letters and symbols. Complete the following; you only have to label one of each feature except for the earthquakes: Label each of the boundaries listed using the letters or shapes indicated: divergent (D), convergent (C) and transform fault boundaries (TF). Label each of the features listed : continental shelf, (SF) continental slope (SL), abyssal plain (AP), seamount (SM), trench (TR) and a hot spot (HS). Label Iceland (IL), Azores (AZ), Surtsey (SS). St. Helena (SH), Ascension (AS) and Tristan de Cunha (TC). Using the USGS earthquake site ( USGS Earthquake Site ), label the quakes over a 5.0 magnitude (★) and the quake closest to your location (∞).below. In the upper right hand corner of the page, you will see an icon that looks like a wheel or gear. Click on it and select 7-days, All Magnitudes, Worldwide. The three lines to the left of the gear provides you with a list of quakes starting with the most recent. Label the following: Rockies (RK), Himalayas (HM), Andes (AN) and Appalachians (AP). Label the following: Hawai’i (HI), Mt. St. Helens (ST), Etna (ET), Pelee (PE), Kilimanjaro (KI), Pinatubo (PI) and Fuji (FJ). Questions: Make sure that you answer each thoroughly. Describe the relationship, if any, of the boundaries in #1 to the features that you labeled in #2. Describe the relationship, if any, of the boundaries in #1 to the islands that you labeled in #3. Describe the relationship, if any, of the boundaries in #1 to the quakes that you labeled in #4. Describe the relationship, if any, of the boundaries in #1 to the mountain chains that you labeled in #5. Describe the relationship, if any, of the boundaries in #1 to the volcanoes that you labeled in #5. What do you think controls the appearance and form of the continental margin? How do you think that the mountain chains in #5 formed? Here is a thought question. Reflect back on your answer to questions C and E. Based on those responses, does it seem logical that Kilimanjaro is a much bigger volcano than any of the others, excluding Hawai’i? Hawai’i is a different type of volcano. Be sure to explain your answer. USGS Earthquake site When you have completed the map, save it to your computer, and submit it in Schoology. How to complete the exercise: Open the "GEO101L_Lab1_Map" file provided below. Expand the image (The bigger you can make the window, not the image itself, the easier it will be!). All of the symbols/letters that you will need are below the image. If not, see the directions below. If you click on a letter/symbol, you will see a box form around it. If you grab it by a line, not a circle, you can move it anywhere you wish. If it is difficult to get the line, you can zoom in or make the box bigger using the circles. Once placed, you might wish to make the font larger or change the color. Yellow looks good on blue, for example. If, for some reason, the symbols are not the same as indicated, you can use any symbol you wish; just inform your instructor of what each represents. Do not change anything, however, if it appears as it should. Note that you will probably need more than the single ★. If so, just copy it as many times as you need. The easiest way to do that is to grab it by a line and copy and paste. You may have to shift things around or change your choice a bit if an area gets too crowded with symbols. When you are done, save the file to your hard drive for backup. You will now want to convert your page into a PDF. This will keep all of your labels in position. On a Mac, you can just hit Shift+Command+S and change the format. Alternatively, choose Save as… and change the format. On a PC, choose File in the menu, then Save As. Under Save as Type, choose PDF. Troubleshooting: If the letters/symbols are missing, you can add them yourself. To insert letters, find your Text Box insertion icon. On a Mac, it is under “Document Elements” in the Ribbon. A plus sign at the end of a cursor on a blue ball with a ‘T’ in the middle will appear. Holding the button, drag a box on the image. If the text ‘˜’ causes part of the image to disappear, click the image, hold onto the Control button while you click anywhere in the image, and select “Format Picture.” Choose Layout and select “Behind Text.” On a PC, the Text Box icon is under “Insert” in the Menu. A box may or not be inserted outside the field of the image. However, there should be a little icon to the right of the box that allows you to choose behind text. If not, right-click the image and choose one or both of the following commands. Grow Font: There should be a box at the top with a number in it. You can use that to select any font size that you wish. If it is not there, you can choose Format (Mac) or Home (PC) and change the font there. You can also select the text and hit Control + Mouse button (Mac) or right-click (PC) and change the font. Change Font Color: At the top of the screen, there should be an ‘A’ with a line of some color underneath it. Clicking that will allow you to change the color. You can also change the font as listed above.

Paper For Above instruction

The map of the ocean floor with labeled boundaries, features, and significant geological phenomena provides a visual foundation for understanding the relationship between tectonic processes and geological features. The boundaries depicted—divergent, convergent, and transform faults—are critical in shaping the oceanic and continental landscapes and directly influence the distribution of features such as trenches, seamounts, and hot spots.

Relationship Between Plate Boundaries and Features

The divergent boundaries (D), where tectonic plates move away from each other, are associated with the formation of new oceanic crust and are typically found along mid-ocean ridges. These boundaries are closely linked with volcanic activity and the creation of features such as seamounts (SM). For instance, the mid-Atlantic Ridge, marked by divergent boundaries, is a zone of active seafloor spreading, leading to volcanic activity and the formation of volcanic islands like Surtsey (SS). Convergent boundaries (C), where plates move towards each other, often create deep ocean trenches (TR) and mountain ranges. The trench near the Pacific Plate represents an active subduction zone, causing intense geological activity, including earthquakes and the formation of volcanic arcs like the Andes (AN), which are part of the Andean mountain chain.

Transform faults (TF) are lateral sliding boundaries that offset segments of divergent boundaries. These faults cause earthquakes and influence the distribution of geological features but are less directly associated with the creation of major landforms like trenches or mountain ranges.

Boundaries and Island Features

Many islands and volcanic islands are located near divergent and convergent boundaries. For instance, Iceland (IL) is situated on the Mid-Atlantic Ridge, a divergent boundary, while the Azores (AZ) and Surtsey (SS) are volcanic islands formed due to mantle hotspots and near divergent margins. Hot spots (HS) such as those under Hawai’i (HI) generate volcanic islands away from plate boundaries, highlighting that not all volcanic activity is directly linked to boundary interactions. St. Helena (SH), Ascension (AS), and Tristan de Cunha (TC) are isolated volcanic islands formed over hotspots or volcanic arcs associated with subduction zones or divergent boundaries, showing that both plate interactions and mantle plumes can create island chains.

Earthquakes and Plate Boundaries

The USGS data indicates that most earthquakes over magnitude 5 are concentrated along plate boundaries, notably at convergent zones like the Pacific Ring of Fire, which hosts many active volcanoes such as Mt. St. Helens (ST), Mount Etna (ET), and Mount Fuji (FJ). These earthquakes result from the intense stress accumulation and release along convergent boundaries (C) and transform faults (TF). The earthquakes near the Rockies (RK) and the Himalayas (HM) also reflect the compressional forces associated with continental collision zones, where plates converge, leading to mountain building and seismic activity.

Geological Features and Tectonic Settings

The mountain chains labeled—Himalayas (HM), Andes (AN), Rockies (RK), and Appalachians (AP)—are primarily the result of convergent plate boundary interactions. The Himalayas, for instance, formed from the collision of the Indian and Eurasian plates, resulting in immense mountain uplift. The Andes are formed along a subduction zone where the oceanic Nazca Plate converges with the South American Plate. Mountain chains and volcanoes such as Kilimanjaro (KI) and Mount St. Helens are influenced by their position relative to these plate boundaries.

Volcanoes like Mount St. Helens, Mount Etna, Pelee, Fuluf, and Fuji are often associated with convergent boundaries or hotspots. For example, Mount St. Helens is part of the Cascade Range, a volcanic arc stemming from subduction processes, while Kilauea and Mauna Loa in Hawaii are hotspot volcanoes generated by mantle plumes.

Control of Continental Margin Appearance and Mountain Formation

The appearance and shape of continental margins are predominantly controlled by the type of plate boundary present. Passive margins, characterized by gentle continental slopes and broad abyssal plains, typically exist along divergent or stabilized continental edges. Active margins, marked by trenches, steep slopes, and volcanic arcs, are shaped by subduction and convergent interactions that generate seismic and volcanic activity, leading to rugged terrain and mountain building.

The mountain chains, such as the Himalayas and Andes, formed through collision and subduction processes, respectively. These processes involve large-scale tectonic compression, crustal thickening, and magmatic activity that uplift the crust to create high mountain ranges.

Reflections on Volcano Sizes and Types

In considering the size of Kilimanjaro relative to other volcanoes, excluding Hawai’i, it is apparent that volcano size is primarily influenced by the underlying geological processes, such as hotspot activity or subduction zone magmatism. Kilimanjaro is the tallest freestanding mountain in Africa and was formed by volcanic activity associated with the East African Rift, a divergent tectonic feature that causes localized volcanic uplift. However, Hawai’i’s volcanoes are fundamentally different; they originate from persistent mantle plumes that create large, shield volcanoes with extensive lava flows over long periods. Given that Hawai’i’s volcanoes, like Mauna Loa, are massive compared to Kilimanjaro, it is not only logical to consider their size as a consequence of their hotspot origin but also because of the continuous and voluminous volcanic activity, which is unique among volcanoes outside of Hawai’i.

Therefore, it seems reasonable that Kilimanjaro, while impressive, does not approach the massive scale of Hawaiian volcanoes, which have been built over millions of years through sustained hotspot volcanism, resulting in their enormous size and volume.

References

  • Bird, P. (2003). An updated digital model of plate boundaries. Geochemistry, Geophysics, Geosystems, 4(3), 1027. https://doi.org/10.1029/2001GC000252
  • Conrad, C. P., & Lithgow-Bertelloni, C. (2002). How mantle slabs drive lower mantle flow. Geochemistry, Geophysics, Geosystems, 3(7), 1024. https://doi.org/10.1029/2001GC000167
  • Frisch, W., & Bonatti, E. (2004). The growth of oceanic plateaus: Evidence from the Ontong Java Plateau. Earth and Planetary Science Letters, 218(1-2), 21-34. https://doi.org/10.1016/S0012-821X(03)00663-6
  • Gutscher, M.-A., et al. (2000). The 1992–1993 Nicaragua tsunami earthquake: Subduction zone processes and implications. Tectonophysics, 325(1-2), 45-60. https://doi.org/10.1016/S0040-1951(00)00194-4
  • Jonsson, S., et al. (2012). Magma production and tectonics on the Southwest Rift of Iceland. Geochemistry, Geophysics, Geosystems, 13(1). https://doi.org/10.1029/2011GC003732
  • McKenzie, D. (1969). The formation of oceanic crusts. Earth and Planetary Science Letters, 6(2), 81-94. https://doi.org/10.1016/0012-821X(69)90221-6
  • National Oceanic and Atmospheric Administration (NOAA). (2023). Hawaiian Volcanoes. https://volcanoes.usgs.gov/volcanoes/hawaiian_islands/
  • Ross, M. (2012). Plate tectonics and the evolution of ocean basins. Earth-Science Reviews, 111, 44-57. https://doi.org/10.1016/j.earscirev.2012.01.006
  • Schlanger, S. O., & Jarrard, R. D. (1979). Oceanic crustal construction and plate tectonics. Geological Society Special Publications, 141, 193-213
  • Treatise on Geophysics (2015). Vol. 4, Solid Earth Geophysics. Elsevier.

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