Post-Ex Flashcards

Question

Varves

Answer 1

A varve is an annual layer of sediment or sedimentary rock. Similar to dendrochronology, varve layers can be counted and a mastetr chronology created back to 52,800 years.

Answer 2

• Radioactive isotopes of Uranium decay to various radiogenic (and insoluble) isotopes, e.g. thorium, protactinium Dating of stalagmites and flowstones • The daughter isotopes (Th, Pa) will only start to accumulate once the carbonates have precipitated; therefore can measure relative amounts and date when flowstone formed

Answer 3

* 40K decays to 40Ar (half life 1250 million years) * Argon is a gas: when a rock is molten (e.g. volcanic eruption) all argon should be released. When solidifies, 40Ar is trapped in rock as 40K decays * Therefore by measuring the accumulation of 40Ar in a volcanic layer, can date time passed since the eruption - can date artefacts between layers of volcanic ash. Need to measure current abundance of parent and daughter isotopes, either: 40K and 40Ar (K-Ar dating) or 39Ar and 40Ar (Argon-Argon dating)

Answer 4

Measuring luminescence which builds up in crystal lattices due to exposure to background radiation This luminescence is released on heating/light; then it builds up again Date: how long since last heating/light Materials: fired pottery, burnt flints, aeolian sediments

Answer 5

stand out in a non-soil landscape. Show that the soil has been moved or disturbed, and shows that building, burial or farming took place there.

Answer 6

buried walls cause plants to grow shorter above them, and buried pits nad ditches cause plants to grow taller above them as they have more moisture.

Answer 7

Light detecting and ranging Uses radar to measure distance to grounds surface -Igrnores tree cover which aerial photography cannot

Answer 8

The most commonly studied archaeological ‘monument’ is the earthwork. In archaeology, earthworks are artificial changes in land level, typically made from piles of artificially placed or sculpted rocks and soil. Earthworks are often known as barrows in England, and mounds in North America. Earthworks can themselves be archaeological features, or they can show features beneath the surface.

Answer 9

collecting objects such as pottery sherds and bone that are on the surface, before or sometimes instead of more destructive approaches such as excavation.

Answer 10

Earthworks, barrows, buried walls and pillow mounds (rabbit homes) are easily visible under low sun and snow cover.

Answer 11

measures variations in magnetic fields. Buried and magnetic haematite is disturbed by digging. It measures the distribution between area and background soil.

Answer 12

measures electrical resistance in the ground. In this type of survey electrical resistance meters are used to detect and map subsurface archaeological features and patterning.

Answer 13

geophysical method that uses radar pulses toimage the subsurface. This nondestructive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures.

Answer 14

A procedure for excavating a circular feature such as a mound, barrow, pit, etc. by laying out trenches. Material is extracted from four quarters of the feature, starting with the two opposite each other and ending with the other two.

Answer 15

uncovering an area layer by layer: the horizontal approach

Answer 16

the vertical approach. Stratigraphic evidence preserved over a large area. Inner walls then removed to show what is underneath them. Developed by Mortimer Wheeler.

Answer 17

evalution trenches. Particularly useful for examining walls and ditches.

Answer 18

To coarse sieve the samples is poured directly on the sieve of desired size and a student would use his or her hands or trowel to encourage the soil through the mesh. The sieve is under constant observation for archaeological material.

Answer 19

Sub-sample or entirety of context • Flow of water directed over soil sample on mesh – collect ‘flot’ and residue and fine mineral particles washed through

Answer 20

Organic rich flots can be sub-divided randomly using a ‘riffle box’ • Flots/residues may be washed/shaken through a bank of sieves of decreasing mesh size

Answer 21

study of pollen Identification of pollen in preserving deposits – Cores provide sequences of change over time

Answer 22

Some species are “sexually dimorphic” – systematic differences between sexes – Teeth (canines) – Horns, antlers – Baculcum e.g tusk from a male pig

Answer 23

Very sensitive to climatic change Usually waterlogged deposits Recovered via wet-sieving and paraffin (keratin absorbs paraffin and floats) Often derive from ditches, waterlogged pits/wells etc.