1 / 9

Collecting Field Data for a Bedrock Geologic Map

Collecting Field Data for a Bedrock Geologic Map. GEOL 3000. Preparation. Establish Objectives Why are you mapping?

jael
Download Presentation

Collecting Field Data for a Bedrock Geologic Map

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. Collecting Field Data for aBedrock Geologic Map GEOL 3000

  2. Preparation • Establish Objectives • Why are you mapping? • - previously unmapped or inadequately mapped area, adding additional level of detail to previously mapped area, trying to solve a specific geologic problem, evaluating economic potential of an area, ... • What are you mapping? • - quadrangle, county, geological unit of interest, area of mineralization potential • What scale will your final map be? • determines the scale of your field map (always map at more detail than the final map) and the coverage of outcrop you acquire • Who will be mapping and where? • - balance expertise, safety, coverage of field parties • Research Previous Mapping and Useful Data • Review published and unpublished maps (e.g. thesis maps, exploration company maps) and related reports or scientific articles • Seek out original field maps and notes if available • Investigate any handsamples and thin sections from previous studies • Investigate any drill core or core logs in your field area

  3. Gear for Northwoods Field Work I’m gonna find me some outcrop today! • Clothing • long sleeve collared shirt • loose-fitting, light but rugged long pants • inexpensive rain pants and jacket • field hat • rugged water-proof boots • field vest &/or back pack • Geologic Equipment • field map and map board • notebook (water-resistant) • Brunton AND orienteering compasses • hand lens, magnet, acid bottle • hammer (and chisel) • pencils (reg. & colored) • sample bags and permanent markers • Other • - insect repellent and more insect repellent • - water (2 liters) • - field lunch (gorp, fruit, jerky)

  4. North Country Exposures

  5. The Field Map • Topographic Base • ~ page size • scale greater than final map scale (e.g. for 1:24,000 map, field map at 1:12,000 or 1:10,000) • add UTM grid for ease of locating • use waterproof paper or laminate • overlay with sheet of mylar • Outcrops • label station ID that matches notebook and sample ID • discriminate rock type with colored pencil • note sample locations • draw strike and dip of measured structures • Other Features • route taken • new roads or trails • possible geologic contacts or faults • other things of note BE ACCURATE BE NEAT! Field Map of part of Tofte 7.5’ quadrangle

  6. Finding Outcrop Start here M486 S80ºW or 260º ~700’ or 1120m ~140 paces massive gabbro

  7. Recording Outcrop Information • Scout around the outcrop: • Make careful observations of rock type(s), • textures, structures; peel moss if necessary • Measure orientation of structures/contacts • Hammer off a piece of rock for a closer look • Take a sample if necessary or important • Take a picture if photogenic exposure • Find a comfortable spot on the outcrop; Apply bugspray if necessary; pull out notebook and map; check GPS location • On the field map, mark: • Route to outcrop location • Area of outcrop - ACCURATELY (in color?) • Station ID# label • Strike and dip symbols of structures • Locations of samples taken • In the notebook, record: • Station ID#, UTM coordinates • Extent, visibility, & type of outcrop • Rock description- mineralogy, texture, structure • Structure measurements • Photographs taken • Samples descriptions

  8. Finding More Outcrop Start here M486 No OC 25o S60ºW or 250º ~1100’ or1750m ~220 paces M487 S75ºW or 255º ~750’ or1200m ~150 paces S5ºW or 185º ~950’ or1520m ~190 paces massive gabbro S-- M488 layered gabbro 20o

  9. Compiling Field Data In GIS

More Related