Elementary Geology Flashcards
What is stratigraphy?
Sequence of
Stratigraphy is the analysis of the sequence of deposits in the earth’s surface that have formed through natural or human activities.
What is stratigraphy for an archaeologist?
Primary basis
“For an archaeologist, stratigraphy is the primary basis for understanding buried materials and provides the most direct information on how objects came to be buried.”
What is the law of superposition?
Younger layers of rick sit atop older layers
What is the law of original horizontality?
Layers of sedimentary rock are originally deposited flat.
What is the law of cross-cutting relationships?
Rock layers one top of one another must be older than the intrusion that disturbs them.
What is the law of lateral continuity?
Layers of rock are continuous until they encounter other solid bodies that block their deposition or until they are acted upon by agents that appeared after the deposition took place.
What is reversal?
Items moved from one location and deposited in another location in reverse order.
What is association?
Items found together within the same layer are likely the same age (or deposited at the same time)
What is bioturbation?
“…mixing, displacement, or modification of the position of materials in the soil.”
Sedimentation
Water
Linked to degree of water flow through grave as it could deposit silts or create fissures. Also affected by evaporation which can cause cracking patterns
What causes compaction and depression?
Anthropogenic cause (intentional compaction of grave soil / shoe print impression / tool compressions) OR natural cause (settling of disturbed soil / collapse of body cavity due to decomp.)
