Archaeology Vocab Ch 2

thermoluminescence (TL)

A "trapped charge," radiation damage technique for dating archaeological objects. Energy produced by natural radiation in soil becomes stored in nearby objects. The amount of energy stored is a function of the level of the background radiation (this can be measured) and time. Once you know the level of background radiation at a particular place, you can measure how much has accumulated in an archaeological object, and from that determine how old the object is (how long it has been accumulating the energy)

osteological comparitive collection

A bone library. A collection of bones used as models to aid in identifying the bones recovered in a paleontological or archeaological excavation.

relative date

A date that places a fossil or archaeological site or artifact in a sepuence with other specimens, bu does not allow for the assignment of an age in terms of years or even a range of years (compare to absolute date)

test pit

A hole or boring into soil in the search for archaeological evidence. In some parts of the world, a pattern of test pits spread out across an area, is a primary method by which archaeological sites are searched for and by which the spatial distribution of buried materials at a site is first identified.

pumice

A light and porous volcanic rock. Pumice forms when a glassy molten froth cools and solidifies quickly.

argon / argon date

A new version of K /Ar dating

activity area

A place where an activity or group of activities were carried out in the past. The activity area is transformed into an archaeological feature by the loss or discard of material items used in the activity--stone tool making, cooking, butchering, burial--that was carried out there.

site

A place where people lived and/or worked and where the physical evidence of their existence in the form of artifacts, ecofacts, and features can be or have been recovered

hypothesis

A proposed explanation for some phenomenon. A hypothesis may be derived initially from empirical observation of the phenomenon; the process call induction. Hypotheses must be tested; predictions are deduced of what new data must be found if the hypothesis is to be supported. When data are found that contradict these predictions, the hypothesis is rejected or modified.

cache

A stash of stuff placed away for safe keeping by ancient people. When the archaeologist is lucky, a cache was not returned to in the past and whatever was stored therein was not retrieved. A cache becomes the equivalent of an unintentional time capsule, providing a cluster of artifacts representing a single time period.

pyroclastic

A swiftly flowing mass of ash, molten rock, and gas spewing from an erupting volcano. Essentially a burning avalanche, the pyroclastic flow that overwhelmed the cities of Pompeii and Herculaneum traveled at speeds of up to 200 kmh (about 125 mph)

pedestrian survey

A systematic walkover of an area in th search for archaeological remains. A pedestrian survey is a useful tool in the search for sites especially where ancient people built structures with durable materials, where natural processes did not cover up materials on the ground, or where natural or cultural processes have exposed buries layers on the surface.

x-ray fluorescence

A technique for identifying the chemical makeup of a raw material. For example, each chemical element in the raw material of an artifact--for example, a flint spear point--gives off a unique set of energies when bombarded with x-rays. The energies released can be read and then used to determine the precise elemental composition of the raw material. The geographic source of the raw material can be determined when its composition as determined by x-ray fluorescence is similar to the composition of a possible source determined in the same way.

accelerator mass spectrometry (AMS)

A variety of radiocarbon dating. In conventional radiocarbon dating, the amount of carbon-14 left in a sample in measured indirectly by the amount of radioactivity the sample gives off. In AMS dating, the amount of carbon-14 left in a sample is measured directly by an actual count of atoms

paradigm

An over-arching perspective, a broad veiw that underlies a scientific discipline.

carbon isotope analysis

Analysis of the proportion of 12C and 13C in a bone or soil sample. Useful in dietary and environmental reconstruction because different groupings of plants use carbon compounds containing 12C and 13C differentially.

absolute date

Any date where a year or range of years can be applied to a site or artifact. As opposed to a relative date where only a chronological order can be established.

radiometric

Any dating technique based on the measurement of radioactive decay

primary refuse

Archaeological artifacts and ecofacs left at the place they were used or produced

secondary refuse

Archaeological artifacts and ecofacts that were removed by the people who made, used, or produced them from the place where they were made, used, or produced, to a designated refuse area or areas: for example, a trash pile or pit

deciduous dentition

Baby teeth. The teeth that are shed like the leaves of deciduous trees.

wear pattern

Characteristic and diognostic traces of damage or polish left on stone tools as a result of their use. Analysis of wear patterns can often tell the researcher how the tool was use and on what material it was used.

feature

Combination of artifacts and/or ecofacts at a site, reflecting a location where some human activity took place. Features include fireplaces, middens, burials, cooking hearths, activity areas, and buildings. Features are also defined as non-portable, complex artifacts.

calibration curve

Curve resulting from the graphing of of dendrochronologically derived dates for an extensive series of tree rings and the carbon dates determined for each of those same rings.

paleomagnetic dating

Dating method based on the movement of earths magnetic poles

luminescence dating

Determining the age of an object by releasing as light, the energy it has accumulated during its existence. The amount of light it emits in this process is directly proportional to its age. Light (optically stimulated luminescence) or heat (thermoluminescence) can be used to release this energy.

trace element analysis

Determining the geographic source of the materials used by an ancient people through the analysis of small or "trace" concentrations of elements or chemicals in those raw materials. The levels measured in archaeological artifacts are compared to the levels present in various possible sources. Where the concentration in an artifact and a source closely match, it is suggested that the prehistoric people obtained the raw material from that source.

sexual dimorphism

Differences in the form and size of the two sexes. Among most primates, males tend to be larger and physically more powerful than females.

ecofact

Element found in archaeological contexts that exhibit human activity, but were not made by people and so are not, strictly speaking, artifacts. Burned wood in a fireplace, butchered animal bone in a trash pit, and charred seeds or nuts in a midden are all ecofacts.

neutron activation analysis

Form of trace element analysis. The precise and unique chemical makeup of numerous raw material sources have been determined through neutron activation analysis. Archaeological artifacts can be analyzed for their chemical makeup as well. When the artifact's chemistry matches that of a source area, it is concluded that the ancient people obtained the material from the chemically matching source.

coprolites

Fossilized feces, useful in the reconstruction of an ancient animal's diet.

taphonomy

How materials become part of the paleontological or archaeological record

palynology

Identification of plants through the remains of their pollen grains. Pollen is morphologically species specific; the ollen grains of each species are recognizably different from the pollen of all other plant species. Recovery at an archaeological site of the preserved pollen of particular species allows for the reconstruction of the plant community present when the site was occupied which can, in turn, inform us of the climate at the time.

varve

Layers of sediment laid down annually in a body of water, usually a lake. Varves may preserve evidence of yearly fluctuations in the environmental conditions in and around the body of water in which they were deposited.

cranial suture

Lines of connection between cranial bones. Sutures appear as squiggly lines on both the interior and exterior surfaces of the skull. Sutures progressively disapper with age and can be used to provide a general estimate for age of death.

morphology

Literally, the study of form. An analysis of the shape and form of skeletons or artifacts.

pollen

Male gametes in plant sexual reproduction. Pollen grains are durable and morphologically species specific. When preserved at or near an archaeological site and recovered from the same stratigraphic level as a site, a general picture of the local plant community present when the location was occupied can be reconstructed.

half-life

Measurement of the amount of time it takes for half of the radioactive isotope in a given sample to decay into stable form. The half-life of radiocarbon, for example, is 5,730 years while that of radioactive potassium is 1.3 billion years.

optically stimulated luminescence (OSL)

Method of luminescence dating in which time-dependant energy stored in an archaeological specimen is released by th eapplicationof laser light.

foraminifera

Microorganisms used in the study of ancient environments. By measuring the ratio of 16O:18O in foraminifera fossils, the amount of the earth's surface covered in ice at any given point in time can be indirectly determined.

phytoliths

Microscopic, inorganic particles produce by plants. Phytoliths are extremely durable and their morphology is species specific. Enormous databases have been compiled that allow the researcher to to examine individual phytoliths recovered int eh soils or adhering to artifacts recovered at archaeological sites and to identify the species from which the phytoliths originated.

archaeomagnetism

Orientation of the earth's magnetic field can become fixed in relatively recent cultural deposits like the sediments in a canal or the clay in bricks lining a kiln. The date of a site can be determined where that orientation points to a location of magentic north already fixed in space and time along a master curve.

K/ Ar dating

Potassium/ argon dating. The half-life of radioactive potassium has been measured to be 1.3 billion years. Since potassium is an abundant element in the earth's crust and since argon collects in rock solely as a result of the decay of radioactive potassium, this technique is widely applicable.

remote sensing

Procedure that allows for the discovery of archaeological sites or artifacts without digging. Remote sensing may include aerial photography and a number of technologies that allow for scanning below ground without disturbing the soil (proton magnetometry; electrical resistivity survey)

carbon dating

Radiometric dating technique based on the decay of a radioactive isotope of carbon: 14C or radiocarbon. Carbon dating can be applied to virtually anything that was once a part of a living organism withing a range from about 50,000 to 500 years ago. Also called radiocarbon dating.

radiocarbon dating

Radiometric dating technique based on the decay of a radioactive isotope of carbon: 14C or radiocarbon. Carbon dating can be applied to virtually anything that was once part of a living organism within a range from about 50,000 to 500 years ago. Aka carbon dating

stratigraphic

Related to the geological or cultural layer in which something has been found. Stratigraphic layering represents a relative sequence of geological time and/or cultural chronology.

association

Term relating to the spatial relationships among archaeological artifacts, ecofacts, and features. Objects found in proximity to each other are said to be in association.

faunal assemblage

The animal bones found at a site and the species represented by those bones.

epiphysis

The endcaps of the long bones. The epiphyses join at the ends of the diaphysis of each long bone.

epiphyseal fusion

The epiphyses of each long bone join to the the diaphyses during the process of physical maturation. The age of death of a juvenille individual can be assessed by reference to the degree of epiphyseal fusion exhibited.

pollen rain

The overall count or percentage of pollens of different plant species falling at a particula place and time.

C4 pathway

The photosynthetic process employed by most grasses and sedges. In the C4 pathway, a radioactive isotope of carbon, 13C, is more readily used than in plants that follow the C3 pathway.

C3 pathway

The photosynthetic process employed by most trees. In the C3 pathway, a radioactive isotope of carbon, 13C, is differentially filtered out.

artificial selection

The process used in the domestication and refinement of plants and animals whereby human being select which members of a species will live and produce offspring. Humans make such decisions on the basis of their needs or desires concerning the form or behavior of the species: plants that produce larger seeds; animals that produce woolier coats; animals that produce more milk.

master sequence

The regional pattern of tree ring width yearly variations. The master sequence for the American west extends back some 9,000 years. When an archaeological tree ring section can be placed within the master sequence, it can be dated directly and this date can be associated with the archaeological site at which it was found.

experimental replication

The reproduciton, under laboratory conditions, of facsimiles of archaeological artifacts. Process employed to analyze ancient technology.

diaphysis

The shaft of a long bone. On either end of the diaphysis there is an epiphysis.

epistemology

The study of knowledge; how you know what you know

dendrochrology

Tree ring dating. By placing a tree section found at an archaeological site within a master sequence of tree ring widths throughout time, the age of the tree (when it died or was cut down) can be determined and associated with the site at which it was found.

isotope

Variety of an element's atomic form. Isotopes are distinguised by the number of neutrons in their atomic nuclei. Some isotopes are unstable and decay into other forms. These are said to be radioactive. Some radioactive isotopes can be used in dating paleontological or archaeological material.

ejecta

all the material thrown out of a volcano during an eruption

photosynthesis pathways

different specific modes of photosynthesis various plant groups employ in the production of energy from sunlight. Most trees employ one such photosynthesis pathway (called C3); most grasses another (called C4)

public symphysis

point of articulation between the to pubic bones of the pelvis. Changes in the appearance pubic symphysis occur fairly regularly during an individual's life and so can be used to determine the age of death.

osteological

related to bones

paleopathology

the study of ancient disease, trauma, or dietary deficiency. Hominid skeletons often bear evidence of these.