Arch GeoPhysics Flashcards
What is Geophysics:
The earth science concerned with the physical process and physical properties of the earth and its surrounding space environment, and the use of technology and quantitative methods.
True or False. GeoPhysical Surveyors typically find out the results of the ground truthing of their surveyor.
False
True or false. Most geophysical surveyors are archaeologists
F
What are some reasons Arch GeoPhys is NOT used in CRM
- Costs too much
- Doesn’t work i.e. unrealistic expectations, poor surveyor, wrong survey method
- Anomalies present but unsure where to dig
- It’ll replace traditional archaeology
Where did many of misconceptions surrounding GeoPhysical study in Archaeology come from?
In the 1980s when the discipline was first gaining traction in the archeological industry it was over sold as a miracle method.
Why should it be used
- Guides and targets future archaeological survey
- Non-Invasive/ Non-Destructive
- Allows for site management
- Increased spatial extent of subsurface knowledge without excavation
- Less cost; if part of research plan
What GeoPhysical technique was introduced in the 40s?
Resistivity
What GeoPhysical technique was introduced in the 50s?
Magnetic testing strategies
What GeoPhysical technique was introduced in the 80s?
high res seismic, ground and space radar, infrared imagery and self potential methods
What have been the primary advances in Geophysical Techniques since the 80s?
Software improvements, imagining, display and GPR
When preforming testing what should your line spacing be?
Depends on what you want to find, but .25 m is typically best
What is the magic number when identifying a pattern?
3
Why is know what your are looking for important in a geophysical test?
Historics show up easer with large, regular anomalies whereas precontract data will be more challenging to tease out. Knowing what you are looking for tells you what sort of anomalies to look for in the data.
How does GPR work?
- Detects abrupt changes in materials below the ground.
- Two antenna one transmits reflects off of subsurface variations (boundaries between contrasting materials)
- One line collects Y and Z data but taking consecutive parallel transects creates 3D data that can be spliced together with programs like RADAN.
What is an anomaly?
A different reflective value compared to the rest of the soils
When reviewing GeoPhysical data, what is important to remember about anomalies?
NOT ALL ANOMALIES ARE ARCHAEOLOGICAL