Question

Use Google Earth. Paste the location that is given into the "Search" box. Examine each location at multiple eye altitudes and differing amounts of tilt. For any measurements that use the ruler tool, this can be accessed by clicking on the ruler icon above the image. Search for \(380112.18 \mathrm{~N} 1214320.02 \mathrm{~W}\) and zoom out to an eye altitude of 30,000 feet. Zoom out and examine the surrounding area, what geological hazards are likely in the area? a. sinkholes b. flooding of urban areas c. erosion and subsidence d. none of the above

Short answer

Flooding of urban areas is the most likely geological hazard.

Step-by-step solution

Enter Coordinates into Google Earth

Open Google Earth on your computer. Enter the coordinates '38°01'12.18" N 121°43'20.02" W' into Google Earth's search bar to locate the area.

Adjust Eye Altitude to 30,000 Feet

Once located, adjust your view in Google Earth to an eye altitude of 30,000 feet. You can do this by zooming out until the altitude shown next to the compass indicates approximately 30,000 feet.

Examine Surrounding Area

While at 30,000 feet, take note of the geography and features of the region. Identify any significant landmarks, bodies of water, or urban areas nearby.

Identify Geological Hazards

Consider the topography, landmarks, and environmental features visible at this altitude. Focus on potential geological hazards such as proximity to water for flooding, land types for sinkholes or erosion, and urban density.

Assess Each Option

Evaluate each option: - a. *Sinkholes*: Typically occur in karst landscapes with limestone; look for signs of this geology. - b. *Flooding of Urban Areas*: Consider any nearby large bodies of water or river systems which could result in urban flooding. - c. *Erosion and Subsidence*: Look for signs of river banks or coastal areas that could experience erosion. Also, consider human activities that might cause subsidence. - d. *None of the above*: Conclude there is no significant hazard if none of the conditions are met.

Determine the Most Likely Hazard

Based on the visual clues and the observations, determine which of the listed geological hazards is most likely in the area. Compare your findings with the clues visible on Google Earth.

Key concepts

Google Earth Tutorial

Google Earth is an incredibly powerful tool that allows users to explore virtually any place on the planet from a bird's-eye view. To begin, you simply need to install Google Earth onto your computer if it's not already installed. Upon opening, you'll be greeted with a digital globe that you can rotate and zoom into different locations. To find a specific place, use the search bar at the top left corner. You can enter an address or even geographical coordinates, like in our exercise. This flexibility means you can explore even the most remote areas of our world.

Once you've located your area of interest, experiment with the controls. You can use your mouse or trackpad to pan around the map, and the scroll function to zoom in and out. Google Earth also offers the ability to tilt the map to view regions from different perspectives. This tool is especially useful when trying to understand the topography of a location, such as hills or valleys.

Eye Altitude Adjustment

Adjusting the eye altitude in Google Earth is like changing your vantage point in the sky. It helps you see different levels of detail or scale. For example, a low eye altitude might let you examine the intricacies of a city street, while a higher altitude could help you study the broader landscape.

To change your eye altitude, you simply zoom in or out until the desired altitude is displayed. This altitude is shown next to the compass tool, which is typically present on the interface. For geological assessments, such as in our task where a 30,000 feet viewpoint is recommended, zoom out until the eye altitude reaches this height. From this altitude, you gain a macro perspective, allowing you to assess large-scale geographic features or potential geological hazards in the broader area.

Ruler Tool Usage

The ruler tool in Google Earth is your go-to feature for measuring distances between two or more points on the map. This can help in geological assessments when you need to measure the potential impact area of a hazard or how close different features are to each other.

To use the ruler tool, select the ruler icon located at the top of the Google Earth interface. Then, click on your starting point on the map followed by your endpoint. The tool will display the distance between these points, which can be adjusted to different units of measure, like miles, kilometers, or even feet. This function is useful for tasks such as determining how far an urban area is from a river, which can be critical when assessing flood hazards.

Geological Hazards Identification

Geological hazard assessment involves recognizing potential risks posed by natural Earth processes. These can include everything from floods and erosion to sinkholes and subsidence. Knowing how to identify these hazards is crucial for safety planning and mitigation.

1. **Sinkholes:** These usually form in areas with soluble rock, such as limestone. Look for circular depressions or sudden changes in landscape elevation.
2. **Flooding:** Consider the proximity to water bodies like rivers, lakes, or ocean coasts. Flood plains are particularly vulnerable.
3. **Erosion and Subsidence:** Coastal areas and riverbanks are commonly prone to erosion. Subsidence, on the other hand, can occur from natural causes or human activities like mining.

By combining observations from Google Earth with geographical knowledge, you can make informed assessments about the potential hazards in any given location. This can help in planning safe residential areas or developing disaster preparedness strategies.