Chapter Four Flashcards
What is geoarchaeology?
study that applies concepts and methods of geosciences to archaeological research
What are the two objectives of geoarchaeology?
- place archaeological materials in relative and chronometric temporal context thru use of stratigraphy and chronometric dating techniques
- understand natural processes of site formation
How can we understand the natural processes of site formation? (2)
- human and natural actions work together to form sites
- geomorphology or the study of landforms and landscapes
What is stratigraphy? (4)
- description and classification of distinct geological layers of the earth’s surface
- stratum: homogenous layer visually separable from other layers by a discrete difference in character
- Law of Superposition: strata at the bottom of a profile were deposited before those on top
- strata are composed of depositional units of naturally occurring material broken down by processes of weathering and erosion and then transported by wind, water, ice or gravity to settle in another location
What are two important case studies involving rockshelters in Nevada?
Gatecliff and Bonneville Estates
What are the three sediment types?
- eolian: transported by wind
- alluvial: transported by water
- colluvial: transported by gravity
What are marker beds, or chronostratigraphic markers?
easily identified geological layer whose age has been independently verified at several locations and whose presence can therefore be used to date archaeological and geological sediments
What is soil?
not depositional, but a developmental sequence of layers formed in place thru pedogenesis
Describe the horizonization of soils in pedogenesis. (3)
- A horizon: top layer, typically dark in color because it is made up of mineral matter that is being mechanically altered by decomposition of organic matter on the surface
- B horizon: below the A horizon, this mineral zone accumulates the oxides and soluble salts that result from movement of water down from the overlying horizon; often red in color, but calcium carbonate-rich sediment may look whitish
- C horizon: below the B horizon, this mineral zone is parent material that remains unaltered by pedogenesis
Describe site formation.
human and natural actions working together to create an archaeological site
What is reverse stratigraphy?
when sediment is moved to a new place and the movement leads to the top of the profile being placed at the bottom of a new location
What are site formation processes?
the ways in which human behaviors and natural actions operate to produce and affect the archaeological record
What are the two contexts leading to site formation?
- systemic context: archaeological materials are actively part of an ongoing cultural or behavior system, including manufacture, use, reuse, and discard of materials (aka active/contemporary depositional context)
- archaeological context: archaeological materials enter the ground and continue to be affected by human and natural processes (aka post-depositional contexts)
What are the two types of depositional processes?
- cultural formation: human behaviors lead to deposition of artifacts, and in some cases redeposition of artifacts
- natural formation: natural actions affect the burial, preservation, and position of artifacts
What are some examples of cultural formation processes? (3)
- reuse: reusing artifacts before they enter the archeological context
- reclamation: moving artifacts from the archaeological context back to the systemic context
- disturbance: modification of archaeological materials in the archaeological context
