Course Outline – Bedrock Fractures

1. Classroom lecture and exercises (8-10 am, 2 hr)
   1. General bedrock geology of Massachusetts and eastern Massachusetts (20 minutes)
   2. Foliation vs. faults vs. fractures (20 minutes)
   3. Introduction to lineament analysis (15 minutes)
   4. Overview of sources for bedrock geologic information in Massachusetts (15 minutes)
   5. Interpreting bedrock geologic maps for hydrogeologic purposes (20 minutes)
   6. Classroom exercise on finding data for site of interest and interpreting likely fracture characteristics and bedrock conditions of sites we will visit later in day. (20 minutes)
   7. Travel to site (10 minutes)
2. Field instruction (10am - 3pm, 1 hour for picnic lunch and transport, 4 hours of instruction)
   1. Sites 1 and 2 in Boxboro, MA - Simple foliation-parallel-fractures, cross-joints, and sheeting joints in Nashoba Formation. Sites are located very close to one another in order to minimize travel time. Participants will be guided through interpretation and measurements at site 1. Site 2 will allow them to practice making observations and measurements in small groups (3 hours).
      1. Methodology for assessing a site
         1. Site tour, noting topography, glacial features, bedrock lithology.
         2. Visual assessment of major fracture sets and structures, what foliation looks like, what to measure
         3. General fracture terminology.
         4. Strike and dip methodology instruction.
         5. Measuring fracture orientation, spacing, trace length, and other attributes.
         6. Quick assessment technique vs. more statistically robust techniques (scan-line method)
         7. How to make a good field sketch fast.
      2. Exercise - break up into teams and measure fractures and related at the site. Data will be analyzed back in classroom at end of the day.

2. Lunch and travel to next Field Site (45 min)
3. Site 3 - Tadmuck Brook Schist, Harvard / Littleton, MA (1 hour)

1. Participants, with help of instructors, assess site with much more complicated fracture sets.
2. Travel back to classroom (10 minutes)

1. Classroom exercise involving Gates Pond Data + fracture data collected from Nashoba formation nearby (2 hours).
   1. Participants will practice summarizing fracture data by graphical means using stereonets.
      1. Theory of sterographic plotting.
      2. How to interpret stereonet plots.
      3. Apply stereonet plots to lineament alanysis and field site characterization.
   2. Participants will work with bedrock well pump test data to evaluate anisotropic flow in bedrock aquifers
      1. Plot and interpret pump test data.
      2. Evaluate how steronets data lend perspective to pump test results.