1 / 15

Puerto Rico Airborne Gravity Data Modeling

Puerto Rico Airborne Gravity Data Modeling. Kevin Brodie II Norfolk State University, Virginia Computer Science Dr. Theresa Damiani (Mentor) National Geodetic Survey Resilient Coastal Communities and Economies. Overview. What is Geodesy? Background Puerto Rico Hypothesis

tobias-landry
Download Presentation

Puerto Rico Airborne Gravity Data Modeling

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Puerto Rico Airborne Gravity Data Modeling Kevin BrodieII Norfolk State University, Virginia Computer Science Dr. Theresa Damiani (Mentor) National Geodetic Survey Resilient Coastal Communities and Economies

  2. Overview • What is Geodesy? • Background • Puerto Rico • Hypothesis • Methodology • Results • Discussion/Future Work

  3. Geodesy is… • The science of measuring the size and shape of the earth, including the gravitational field and its locations throughout different points in an area. Geoid is simply a surface of equal gravity potential energy. The Earth’s mass is unequally distributed causing certain areas to have a greater gravitational pull which makes the geoid seem to have bulges.

  4. Background • The Airborne gravity data was collected by the National Geodetic Survey’s GRAV-D program there in 2009. GRAV-D surveyed Puerto Rico and the islands in the marine areas to the north and south, where the Puerto Rico trench and other ocean floor features are located. Atlantic Caribbean

  5. About Puerto Rico Different classification schemes exist for the soils of Puerto Rico.  Five general soil types: humid coastal plains, semiarid coastal plains, humid uplands, semiarid uplands, and humid upland valleys.  The territory is very mountainous (covering about 60%), except in the regional coasts, but Puerto Rico offers astonishing variety: rain forest, deserts, beaches, caves, oceans and rivers.

  6. Hypothesis This research project has the objective of better understanding the setting and geologic composition of PRVI, which is important for NOAA’s use in geodetic modeling of the area. We hypothesize that using gravity data files for the 2D modeling of topography and bathymetry of PRVI, gravity anomalies, that are produced from algorithms of code, can be calculated and graphed in MATLAB. Finally the created 2D model will have polygons that are added that mimic oceanic crust and mantle. These polygons drastically effect the model’s gravity and are tweaked in order for the model gravity to match actual airborne gravity survey data in 2009. Then the model that is created is interpreted in order to better understand the composition of the islands.

  7. Methodology Latitude Longitude Full-field gravity (mGal) Free-air gravity (mGal)

  8. Topography Caribbean Bathymetry Atlantic Bathymetry

  9. This boundary that separates two different densities of rock is what gives the gravity reading Oceanic Crust density=2.9733 Oceanic Crust Density = 2.97 g/cm For each polygon there is a calculation done for each point separately to find the gravity. Mantle density =3.3 g/cm Mantle density=3.3 A rigorous process of editing the model to produce a similar gravity reading to the measured gravity is done.

  10. Results • This project was the 1st step in modeling more complex diagrams and figures of the PRVI • The topographic and bathymetric models of PRVI were created with MATLAB; along with that, realistic gravity signals were calculated using different algorithms. • Gravity and model results were consistent among other researchers work. • There was a distinct protruding mass of mantle that was found and observed. • Knowing the gravity, sea level can be located, which in turn improves the accuracy of elevation measurements in Puerto Rico Caribbean plate Atlantic plate

  11. Discussion/Future Work

  12. This project was one component of many that leads to the updating of the vertical datum. Knowing where the density changes among land, gravity can be calculated Resilient Coastal Communities and Economies Based off of the gravity information, Sea level can be located With actual Sea level heights known, the vertical datum can be updated With the vertical datum more accurate, this allows the coastal communities to be further prepared for natural disasters

  13. Images collected by NGS emergency response team of post-Sandy destruction. Houses and roads washed away by storm surge illustrate the importance of knowing sea level and heights above sea level. Coastal communities can rebound from storms more quickly, with less damage, if we know which areas are in the most danger from rising waters during storms

  14. Acknowledgements • A special thank you to: - Dr. Theresa Damiani - National Geodetic Survey - Office of Education Scholarship Team - Fellow EPP Scholars

More Related