Part 1 - Download the data

1. Download the data (Excel 2.1MB Jan22 25) which was obtained from Michael Carr's websiteat Rutgers University. Dr. Carr is a petrologist who has studied Central American volcanoes for many years.
2. Open the file you just downloaded and click on the CAVF tab.  Here you will find data for at least 41 Quaternary volcanic centers that comprise the volcanic arc in Central America. Note that each row contains data for a rock sample from a volcanic feature within one of the 41 volcanic centers. Take particular note of the following columns:
   • Column B: country of origin
   • Column C: sample number
   • Column N: volcano name
   • Columns U-AG: major-element data
   • Columns AH-BX: trace-element data
   • Columns BY-CE: radiogenic isotope data
   • Column CH (vDistance): the distance in km along the volcanic arc from some arbitrary starting point towards the NW end of the line of volcanoes. "Distance" increases as the volcanic arc is traversed from Guatemala -> Honduras -> Nicaragua -> Costa Rica. This variable will simply be referred to as "Distance" for the remainder of this exercise.
   • Column CI (vBack): approximately the distance in km behind (to the NE of) the trench
   • Column CR (Ht-km): height of the volcanic feature above sealevel
   • Column CS (EdificeHt-km): height of the volcanic feature above the surrounding topography
   • Column CT (Volume-km3): volume of the volcanic feature (shields and stratovolcanoes will have large volume, while individual lavaflows or cinder cones will have much smaller volumes)
   • Column CU (CenterVol-km3): volume of the volcanic center of which the volcano is a part
   • Column CV (Crust-thick-km): the thickness of the continental crust beneath that volcano as determined by seismic surveys