GLG410--Computers in Earth and Space Exploration

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Query and processing of vector data with application to Arizona seismic hazard

You have now learned the basics of creating and working with both rasters and vectors in ArcMap. In this exercise, we want to give you a chance to work with some vector data to do some queries and other processing to answer an earth science question. In this case, the example will come from Arizona and its earthquake hazards (overall and then for Scottsdale in particular).

Step 1: Gather the data

For this exercise, you will need the following data:

Step 2: query the shapefiles

In this example, you are learning how to find certain features in the shapefiles that satisfy a given query.

Find Greater Phoenix's outline

The urban boundaries are in the urban.shp that you downloaded above.

Video explanation:

Step 3: compute a buffer around your selection

The new national earthquake hazard standards say that any active faults within 50 and also 100 km have to be accounted for. A buffer is a zone around a map feature measured in units of distance or time.

Compute a 50 km buffer around greater Phoenix

Video explanation:

Step 4: query to find what features are inside of another polygon

Now that we have the 50 km polygon, you can query the faults shapefile to find all the faults that are inside of it.

Which faults are inside the 50 km buffer around greater Phoenix?

Video explanation:

Application to study of all of Arizona's active faults

In this case, we want to find all of the geologic units in Arizona that are Quaternary age and compare them with the active faults.
Knowing what you know above, this is pretty easy. It just uses a big query on the Geologic map.
Video explanation:

Exporting a layer's Attributes tables from ArcMap to Excel

Sometimes it is useful to have a layer's attributes in table form (e.g., if we want to further explore the data that go into a layer. This can easily be done as follows:

Assignment 11: Hazards Maps

Part 1: Seismic hazard analysis for Flagstaff or Tucson area active faults

Perform a similar analysis to find the active faults in the area of Flagstaff or Tucson areas (your choice). Please make an appropriately symbolized map and also present the table of faults.

Part 2: Active faults and Volcanoes for Arizona

As above, find all of the Quaternary alluvial units in Arizona, but also find all of the units that have Q and V or v or Qb or Qtb in them. That would be all Quaternary volcanic rocks. Also find all of the units that have T and V or v or Tb in them. That would be all of the Tertiary volcanic rocks. Extract the Arizona outline from the states.shp shapefile that you have. Use the select by location to get all of the faults that are contained in the Arizona outline.

Make a map that has the active faults in Arizona in red, then the Quaternary Volcanic units all in light red or pink, the Tertiary volcanic rocks in orange, and then the Quaternary in yellow, all over the shaded relief. Where are the faults that cut Quaternary? Where are the places with the Quaternary volcanism? Where are the places that have Tertiary volcanism? What was the change in loci of volcanism from the Tertiary to the Quaternary?

Grading Rubric (50 points)

Assignment is due Tuesday, November 22, 2011.
Last modified: November 13, 2011