June 5, 1997 Progress and Plan

Scott Veirs

These ~2 pages (of text) present my research (and academic) progress during the past 6 months, and research plans for the upcoming 6 months. It is available with pertinent (underlined) links at http://www2.ocean.washington.edu/~scottv/academic/progress/june5.97.html.

In accordance with the Graduate Student guide (p.9), after the committee meeting (see agenda below), I will prepare a 1/2 page summary of progress made to date on previously agreed upon goals, detailed goals for the next 6 months, and a listing of committee recommendations.

Meeting Agenda: June 5, 1997, (11am, MSB 269)

  1. 10 minute presentation by Scott of research plans
  2. 20-40 minute discussion of:
    1. Targeted research objective
    2. Attainable goals and deadlines
    3. Opportunities for creativity
    4. Potential seques to a PhD dissertation topic?
  3. Additional committee recommendations

Progress
Research | Academic | Educational Experience

Plan
Research Objectives | Outlined Plan

Research Summary

After interaction with scientists (primarily Baker and Lavelle) at the Fall AGU meeting, I returned Winter quarter to the exploration of near-bottom hydrographic features in the Mixing Zephyr data set. With reference to the plan formulated in the December advisorial meeting, I have accomplished some, but not all of my goals.

Dr. Rhines's course offered a (rarely offered) opportunity to investigate the behavior of focussed and diffused flow of buoyant fluid in non- and linearly-stratified environments. While my geophysical fluid dynamics project results were primarily qualitative, the class helped me to understand how classical plume theory and the work of D. A. Trivett might be applied to analysis and interpretation of the Mixing Zephyr measurements.

While I have not yet consulted Dr. Lavelle about numerical modelling of plumes and/or diffuse flow, I have become more familiar with the field data. I continue to assess how to calculate salinity and thermal anomalies that account for variability in source properties (q-ness); I have catalogued the general characteristics of Mixing Zephyr hydrothermal activity (depth distribution of effluent, source depths and characteristics, typical plume rise heights); and I have begun to test the hydrographic utility of potential temperature, salinity, and potential density gradients.

Aiming to constrain the source of anomalous fluid through an assumption of minimal diapycnal mixing subsequent to equilibration in the water column, I have examined the density structure over the Endeavour ridge -- both along- and across-axis. On average (in space and time), the isopycnal surfaces are horizontal planes. After considering the Hydrosweep depths measured for known and suspected buoyancy sources, I am gaining confidence that -- if the assumption of minimal diapycnal mixing is correct -- there are distinct hydrothermal sources in the following areas:

  1. North horst
  2. Side scan sonar target
  3. Between Mothra and Main fields
  4. Perhaps atop the western axial valley wall

Academic Summary

Winter Quarter 1997 Courses

Winter Quarter 1997 Grade Summary

Cumulative Summary through Winter Quarter 1997

Spring Quarter 1997 Schedule

Pedagogical Experience

In collaboration with Christian Parker and Melanie Summit, I visited the school of one of the REVEL participants, presenting a short course on hydrothermal vent systems to a group of 6 elementary and secondary school students over 5 days.

(Back up to...) Progress
Research | Academic | Educational Experience

2 Year Plan

I would like to work hard this summer with the goal of receiving a Masters degree prior to pausing for 2 years in my progression towards a PhD. My primary motivations are:

  1. Live closer to Annie, until she completes her rotations; then return with her to Seattle to simultaneously engage in further MORP research and a medical residency, respectively.
  2. Through collaboration with scientists in the Bay Area (NASA Ames, USGS Menlo Park, Stanford, ...) fufill more directly the objectives of my Earth Systems Science Fellowship proposal.
  3. Seek teaching experience, either as a teaching assistant (Stanford Earth Systems Program, or returning to UW Oceanography for a quarter), or an employee of an innovative educational service (the Sea Education Association, for instance).

My hope is to remain enrolled as a full- or part-time student during the first year, and then to petition for On-Leave status (outlined on pg. 13 of the School's Guide for Graduate Students). If necessary, I will petition for 2 years of On-Leave status.

I realize that significant progress this summer will be crucial to accomplish this goal. I will be dedicated to the task throughout the summer, and am eager to work with my advisors to delineate the central questions and logistical tasks that will underpin a late-August presentation on "Evidence for diffuse flow at the Endeavour Segment, and its distribution within a regional hydrographic context."

My greatest fear is that the Mixing Zephyr data does not contain sufficient evidence of diffuse flow to allow meaningful mapping of its distribution. I would greatly appreciate it if you could bolster my confidence in this regard!

Remaining sensitive to where there is (most likely) sufficient information available, I have outlined a logical structure that I believe leads most efficiently towards a Masters presentation and a subsequent publication. During my June 5 committee meeting, I would like to focus upon presenting and refining this outline, and deriving from it more specific, attainable goals and corresponding deadlines.

Logical Outline

  1. Define "diffuse flow"
    1. Summarize what is known from sea floor observations about the distribution (map!) and character (S,T,X,chemistry) of "diffuse" and "focussed" hydrothermal activity.
    2. Through theoretical arguments, predict the water column signature expected from the observed sea floor sources -- particularly the diffuse flow sites.
      1. Rise heights (MTT -- Trivett)
      2. Diapycnal mixing and source elevations (turbulent diffusivities for T,S?!)
      3. q-ness?
      4. Entrainment considerations
  2. Discuss new approaches to mapping (diffuse flow)
    1. Isopycnal bounds
    2. q-ness ==> independent anomalies of S and Theta
    3. Gradients (S,T,X)
    4. Diagnostic ratios of parameters, or chemical constituents (bottle distribution!?)
  3. Present tests of new hydrographic approaches
    1. Groundtruth and hydrography of diffuse flow site(s) (Clam Bed? Cirque? Dune?)
    2. Groundtruth and hydrography of known fields (Dante? Mothra? Salty Dog?)
  4. Results of new methodology
    1. Hydrography of suspected sources (Inter-field? Mothra?)
    2. Distribution of diffuse sources (North Horst? Side scan sonar target?)
    3. Distribution of "ground fog" (Diffuse flow effluent??)
  5. Interpretation (integrate hydrothermal vent system theory[Cherkaoui, Parker] and independent observations of morphology[Bhat], crustal structure[Archer], geochemistry[Bain], etc...)