1. Tip Meckel Ph.D. Candidate Geological Sciences
Characterizing Fault Populations and Seismicity on an Active Plate Boundary Using GIS
Tip Meckel
Ph.D. Candidate
Geological Sciences

2. Outline Reasons for study Data Sets Involved in Study GIS Project
The Macquarie Ridge Plate Boundary
Data Sets Involved in Study
GIS Project
Results and Significance
Conclusions

3. Why Study Plate Boundaries?
Seismic Hazard
Better understanding of
tectonics is important!
Images courtesy of USGS unless noted otherwise

4. What are plate boundaries?
Basic concepts

5. The Macquarie Ridge Plate Boundary
Benefits of studying this boundary
Similar to San Andreas Boundary
It is completely naked!

6. Flying over the Macquarie Ridge!
Movie courtesy of the Australian Geological Survey

7. Why use GIS? Interpretations rely heavily on maps
advantage to having data incorporated into map in table form
Spatial analysis of features and associated data

8. Data sets using: Entire Dissertation: GIS Project:
Remotely Sensed Data from Ship: Bathymetry, Sidescan Sonar, Gravity, Magnetics, and Seismic.
GIS Project:
Line coverage of Faults interpreted on seafloor
Point coverage earthquake data from USGS
Bathymetry?

9. GIS Project Import line drawing into Arc Format
Convert line drawing to ASCII and import
Thanks to Christina Massell and Chris McFarlane
Obtain USGS earthquake data and convert to a point coverage in correct latitude /longitude projection
Use data table to color earthquakes according to magnitude and depth

10. GIS Results I

11. GIS Results II

12. Faults greater than 0.231 units

13. Earthquake occurrence by year

14. Earthquake occurrence by depth

15. CONCLUSIONS
The lengths of faults follow an exponential distribution - this has not been documented and may be suggestive of fundamental processes at plate boundaries.
The spatial occurrence of earthquakes over time and with depth is NOT random. This likely indicates the current state of stress at the plate boundary. There may yet be some hope for more complete understanding of tectonics!

16. Future Directions
Incorporate bathymetry, gravity and magnetic data into map. This has thus far been stymied by the format of the ship data.
Pursue ideas generated by distribution of fault length data. What can the distribution tell us about fundamental faulting processes at plate boundaries?