Thursday, February 7, 2008

Feb. 7: Fieldwork



Feb. 7
Reading for today:
Ashmore and Sharer, Chapter 5, "Fieldwork," pp. 87-124.
Feder, Chapter 10, "Good Vibrations: Psychics and Dowsers," pp. 261-277.

Fieldwork



ARCHAEOLOGICAL SURVEY

Archaeological survey: Methods archaeologists use to locate sites or acquire data from sites or regions without excavation; observing surface remains and using remote sensing for surface and subsurface remains (ibid. 87). Includes ecological factors. Reveals site numbers/types/form/size/spatial distribution. Not all sites found by survey, some known from history or general knowledge. High quality maps and/or aerial photographs necessary to plot site locations.

Three Basic Methods of Site Discovery:

1. Surface survey: Direct inspection of the terrain while walking at ground level, also called archaeological reconnaissance or reconnaissance survey. Should be done along transects at set intervals based on initial plans, but sometimes field conditions require rethinking the strategy. Oldest and most common survey method.

2. Aerial survey: Survey from above, including aerial photography (high altitude, low altitude, and radio-controlled airplanes with rigged cameras). Low raking light at sunrise and sunset very helpful. Not just regular film, use also infrared, radar, thermography (differential heat on ground). Satellites also used at times; for example Landsat especially useful for roads and regional studies. GIS (Geographical Information Systems) data incorporate multiple sources. All remote sensing techniques require ground truth (or "ground truthing") which simply means physically checking the ground itself to check the features being interpreted in the aerial photos, for example.

3. Subsurface survey: Survey of resources under the surface, either by direct intrusive methods like auguring, coring, or shovel testing (this last is the most common and often done on archaeological reconnaissance if the soil development indicates the likelihood of subsurface deposits; such tests are done on transects, and are often called STPs, or shovel test pits), or remote sensing technologies :
-- magnetometer (for variations in magnetism under ground, as with certain kinds of stone features like walls, or large areas of fired materials like clay in kilns)
-- resistivity detector- measures the differences in subsurface features to conduct electrical current, often because of moisture differences
-- ground-penetrating radar- sends back echoes revealing different densities below surface

These last three technologies require expensive technologies, expert interpretation of the results, and are generally limited in usefulness to larger built subsurface features and remains like walls and floors of structures, and sometimes burials
Not mentioned in the text, archaeologists have also used metal detectors, especially for systematic battlefield surveys; one of the first and most famous examples of this use was at the Little Bighorn Battlefield in Montana.

Once a site is located, it is given a trinomial designation in the U.S. as I described in the last class; other numbering or naming systems are used in other countries. Sites are sometimes also given names, either the historic name if known (Diamond City, near Helena), or as is common in the U.S., a landowner's name (MacHaffie Site, near Helena) or descriptive term (Pictograph Cave, near Billings). Finally, sites locations are established using satellite-based GPS (Global Positioning Systems). This is only a consistent development over the last ten years or so; back when I was doing surveys we used only a topographic map and the UTM system (boy that was fun…you young whippersnappers don't know how easy you got it these days!)

After a site is located, by old-fashioned walking or by one of the remote-sensing based surveys, then it all comes back to walking the ground, mapping the site, and describing what is seen on the surface. The site is mapped, either using traditional mapping technologies such as the transit, or newer technologies such as the laser transit and GPS. Topographic maps and planimetric maps can provide different views of the same site data.

EXCAVATION

Excavation is the principle method that archaeologists use to recover data beneath the surface, and is also sometimes a method of discovery. Subsurface remains are generally the best preserved and least disturbed data (but not always…note that subsurface remains can suffer massive disturbance through rodent burrowing even within recent years… and that some surface remains have laid essentially undisturbed for thousands of years in high remote deserts!)

The two basic goals of excavation:
1. Reveal the three-dimensional patterning/structure in deposition of artifacts, ecofacts, features; evaluation of the provenience and association
2. Assess the functional and temporal significance of the patterning; evaluation of the context
The goal is to reconstruct the past behavior; proper and complete records are VITAL to this effort-- archaeology without proper recordation, notes, maps, etc. is simply LOOTING

For the three-dimensional patterning, it is important to note the distinction between the two horzontal dimensions of a surface (usually synchronous..of the same time period), and the one of depth (usually diachronous…of different periods)

Stratigraphy

Stratification- observed layers of matrix (pl. matrices) and features; each layer is a stratum (strata is plural)

Law of Superposition- geological principle that the sequence of strata from bottom to top reflect the order they were laid in, from earliest at the bottom to the most recent at the top (Please check out the figures in your text for a nice illustration, fig. 5.14 on p. 104 and fig. 5.15 on page 105) Even though there may be cases of reverse stratigraphy that seem to fly in the face of the law of superposition, it still holds true (see fig. 5.15, p. 105).

Stratigraphy- the study and interpretation of stratification. Looking for evidence of redeposition or disturbance--sometimes clarification in complex cases is assisted through conjoining studies ("refitting studies") in which fragments of artifacts and ecofacts from different strata are fitted back together. Stratigraphic evaluation includes both temporal and functional evaluations.

Nonarchitectural features: middens, burials, hearths, quarries
Architectural features: walls, floors, platforms, staircases, roadways

One way to approach stratigraphic evaluation is by using a schematic diagram called a Harris Matrix, a way to abstract the relationships between various stratigraphic elements (see fig. 5-16, p. 108)

Excavation Methods

There are two basic kinds of excavations:

1. (Vertical) - Penetrating excavations- Mainly going deep vertically, to see in cross section the depth, sequencing, and composition of the deposits; test pits, trenches, tunnels.

2. (Horizontal) - Clearing excavations- clears occupation levels horizontally to see the extent of the deposit and the arrangement of features/artifacts/ecofacts of the deposit

Usually both types are excavation are used at a site to fit the different goals of research. Excavation is like taking apart a giant 3D puzzle, and putting it back together on paper/computer…thus the vital importance of complete notes and recordation!

The Toolkit
Take a look at the tools for an excavator's toolkit on p. 111…I will comment for you to note that the "gold standard" for archaeologists is the sharpened Marshalltown triangular trowel (medium size)…it is the identifying badge of the profession of field archaeologist beyond all others! At the minimum you also need a good compass (Brunton is the ideal, but Silva is ok too), folding rule, and tape measure (metric for prehistoric, standard inches and feet for historic). Add a shovel (flat-nose for excavations!) and a good screen, and by gum, those are the essentials.

Micromorphology- The microscopic study of fine deposit residues cut from excavated matrices such as floors.

Provenience Control

Horizontal and vertical provenience must always be the guide and structure for excavation; words fail here…Be sure and look at the excellent diagrams of the grid and excavations on pp. 112-113. It is one of those things easier to show than to tell.

Remember…excavation of a site is destruction of the site. Without proper controls, notes, and research design, there is little noticeable difference between archaeology and looting.
The goal is to take enough proper field notes, scaled drawings, photographs, and standardized info on forms, to be able to reconstruct the site as an ideal.

Field drawings are done as:
1. Sections (side/profile view, or vertical/stratified sections; arifacts in the unit walls, etc.)
2. Plan view (horizontal relationship of features and artifacts/ecofacts)

DATA PROCESSING

Data are collected (artifacts, ecofacts, soil samples from the matrix and features for pollen and other analysis, etc.). There are established systems of collecting, storing, processing, and labeling/storing the data for efficient retrieval later (much like a library or archives). Ecofacts are usually processed by specialists in faunal analysis, floral analysis (including pollen or phytolith analysis), etc. Lithic analysis is also important to understand where the source materials for stone artifacts originated.

CLASSIFICATION

Classification is the process of rearranging or ordering objects into groups on the basis of shared characteristics that archaeologists call attributes.

An attribute is any observable trait that can be defined and isolated. Three basic categories of _directly observable_ attributes are used in archaeology, and the classification will depend on the research questions being asked:

1. Stylistic attributes: color, surface finish/texture, decoration (painted/unpainted), alterations, etc. Stylistic types include pottery classifications based on decoration and finish (ex: the many types of pottery styles of the Pueblo Indians of New Mexico

2. Form attributes: overall 3D form and aspects of the artifact's shape; dimensions (metric attributes)- length, width, thickness, weight. Form types include pottery component shape attributes (ex: thickness of wall, curve of wall, strap or loop handles) or grinding stones cross-sections (ex: round, rectangular, etc.)

3. Technological attributes: raw materials (constituent attributes) and traits relating to the manufacturing process. Technological types include metallurgy processes (ex: different alloys of copper such as brass or bronze) and kiln processes (ex: tempering of sand using sand grit or crushed shell)

Besides classification based on _directly observable_ attributes, artifacts can be classified using _inferred attributes_ measurable only by tests such as spectrographic or chemical analysis, which are not done in the field.

Classification serves 4 basic purposes:

1. Classification divides a mass of undifferentiated data into groups/classes

2. Classification allows the researcher to summarize characteristics of many objects by listing only shared attributes through the definition of …
---------Types: represent clusters of attributes that occur together repeatedly in the same artifacts. For example, Oneota Allamakee Trailed pottery which my tribe the Ioway made in precontact times, is typically distinguished by generally globular form (form attribute), trailed decorations such as chevrons (stylistic attribute), and shell-tempered clay (technological attribute)…other types of precontact pottery in the Midwest may have one or the other of these attributes, but all three attributes taken together make up the Oneota Allamakee Trailed TYPE.

3. Classification defines variability of the artifact, which can lead to further to understanding, as when variability in pottery in some cultures relates to social subgroupings of status or lineage identity.

4. Classification, by ordering and describing types, enables the researcher to suggest a series of relationships among classes.

Ultimately there is no right or wrong classification scheme…it is only a working cognitive tool to get at answering a particular research question. For example, for pottery, if one is studying food storage, one might choose to classify based on form attributes, but if one is studying social identity, one might choose stylistic attributes instead.

It is also possible to relate hierarchies of artifact classifications with hierarchies of social groupings, but depends on the base data.
- Individuals make artifacts based on cultural standards, or norms (attributes).
- Subassemblage -Patterned set of artifacts used by occupational or other groups (hunters, farmers, mothers, etc.).
- Assemblage -Patterned set of subassemblages that represent a community's behavior patterns.
- Archaeological culture -Patterned set of assemblages, sum total of material remains, assumed to represent the culture of a past society


Sites and other subjects also mentioned in this chapter:
Stonehenge (Britain)
Tehaucan Valley (Mexico)
Athens, Rome, Carthage (Mediterranean region)
Troy (Greece); Heinrich Schliemann
Olduvai Gorge (Tanzania); the Leakeys
Lascaux Cave (France)
Tell / tepe - hill/mound (term used in SW Asia/Middle East)
Shahr-I Sokhta (Iran)
Sarepta (Lebanon)
Nile Valley (Egypt)
Sybaris (Greece)
Cahokia (Illinois)
China Lake Valley (California)
Teotihaucan (Mexico)
Pompeii (Italy)
Cerén (El Salvador)
Koobi Fora (Lake Turkana, Kenya)
Lindenmeier Site (Colorado)
Royal "Acropolis", Copan (Honduras)

FEDER

FEDER's chapter on "Good Vibrations: Psychics and Dowsers" is a good match for the Ashmore and Sharer chapter. Feder discusses the real life hard work of finding and excavating sites (which I can vouch for personally), compared to the fantasy of being able to predict where a site is using a dowsing rod or pretending to be able to see into the past and explain what happened at a site.

Claims that are not testable, through excavation, etc., are not science. The evidence of incidents that have been tested does not support the claims of psychic archaeology or dowsing for sites.

On the other hand, Feder is pretty dismissive of water dowsing, but my very down-to-earth Grandpa swore by it, and he and his dad could dowse for water. I do not claim that ability. But then my Grandpa actually tracked down a Will-o-the-Wisp in his youth in the dark brush along the Missouri River in pre-WWII Nebraska, when no one else would go with him because they were afraid of ghosts. He didn't believe in ghosts, as he had never seen one. But the Will-o-the-Wisp he tracked down was actually a piece of phosphorescent wood, its internal gases causing it to float its ghostly way through the dark trees. Grandpa caught that Wisp that dark night…but he didn't crush it like lesser men when confronted with the unknown…he let the Wisp-wood go, content with discovering its mystery, and letting it go on its own mysterious way.

Archaeology is a matter of hard work, though we wish it were otherwise…wishing doesn't make it so.

I believe there is room for science and for mystery in this world. The trick is to not be deceived, and confuse one for the other. Science is an astounding tool to discover empirical truth…but it is a very cold God.

Next Time: Fieldwork
Readings for Next Class on Tuesday:
Reading assignment for next class: Ashmore and Sharer, Chapter 6: “Analyzing the Past,” pp. 125-156.

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