Archaeology for Teachers

Field School 2005

Patty Finger

June 2005

The Tools

Bags to hold artifacts and Sharpies to label the bags

Wire brush to

clean equipment

Trowels for skimming

Mea

suri

ng

tap

e Nails to mark unit or to set datum

Clippers to cut roots

Paint brushes clear soil from artifacts

Bamboo picks help to clear soil from around an artifact

Files keep tools sharp

Tool ChestFilm canisters keep fragile items safe

The Process

Setting Up a Unit

2 meters

2 m

eter

s

Standard archaeological units are 2 meters by 2 meters. These units lie within a grid established from a fixed starting point.

Who was Pythagoras?

Archaeologists use the Pythagorean theorem to find the hypotenuse of a right triangle. If all the measurements are correct, the units are square.

a2 + b2 =c2

Dig, Dig, Dig!Once the unit is laid out, ground breaking begins as you dig through the plow zone. The pile of dirt and sod that is created is known as the back dirt pile. It is always in the wrong place!

Skimming Off the Plow Zone

The plow zone is a 25 cm layer (approximately) that is disturbed by the plow. Artifacts found in this area indicate the possibility of a site but not an exact location.

Archaeologists need to get below the plow zone to find in situ artifacts.

Putting the Trowel to Work

The trowel helps level the unit and makes any stains more pronounced. Make sure you trowel in the same direction to avoid trowel lines.

Looking for Stains

A stain is a color variation in the soil. Stains give archaeologists an indication of past human activity.

Do you see the stain?

Setting the Datum

The datum is the point archaeologists use to measure from. They measure down from the datum line which has a level attached. This keeps each level an equal distance below the datum point.

Layer by layer

A layer of 5 cm of soil is removed from a feature. This is called a level. Levels are identified by a sequential level number and the measurement below datum (cmbd).

Anything found in the layer is placed in an artifact bag and labeled.

The Matrix

Matrix is a sample of soil from the level of a feature. The matrix is floated to collect very small fragments like charcoal, pollen, or seeds.

What’s missing from my label?

What were all those numbers?47LC333

•47 – Wisconsin

•LC – LaCrosse County

•333 – 333rd site in the state

F14 E½

•F14 – Feature #14

•E½ - East half of the feature

Level 9

•The ninth level excavated; can also be written as L9

60-65 cmbd

•The top of the level was 60 cm below datum and the bottom of the level was at 65 cm below datum

06-28-2005

•The date excavated

Did you figure out that the acquisition number is missing?

Screening

Soil not collected in a matrix is screened at the site. Artifacts found in this process are also bagged and labeled.

Using the Bamboo

A bamboo pick is used to remove soil from around an artifact so it can be removed without damage. It is also used to create a pedestal under the

object so the entire item can be exposed without removing it. When several items are exposed in a single layer, an archaeologist can use the

context to draw conclusions about past human activities.

Painting – sort of!

A paint brush is used to clear loose dirt from off of or around an artifact. This prevents damage to the artifacts.

Mapping the Feature

Once the level has been completed a map must be drawn of the feature. Careful measurements are taken and any artifacts that extend beyond the level, large artifacts in situ, additional stains and rodent disturbances are placed accurately on the map.

Paperwork Every level has an Excavation Level Form. The excavator indicates the site, feature, half, level, cmbd, methods used for excavation, screening, artifacts found and comments about the level.

Acquisition numbers at the top are used to label matrix and artifact bags.

Field Journals

An archaeologist keeps a field journal. She records daily what has been done, how it was done, what was found and any other observations about the site.

What happens to the artifacts?

Artifacts are placed in resealable bags. The acquisition number and provenience information are written directly on the bag along with information or instructions about the artifact. Very small, fragile artifacts like bone or shell may be placed in film canisters and large chunks of charcoal wrapped in foil for carbon dating purposes.

Finishing Touches

The Munsell book is consulted to find the soil color. The soil color is indicated on both the map and the Excavation Form.

A photo is taken as a second record of the finished level.

When the paperwork is finished, the feature mapped and the photo taken, the archaeologist tackles the next level. If sterile soil (soil outside the stain area) has been reached, the archaeologist goes back to the plow zone.

What was hidden under all that “dirt”?

47LC333

F14 E½

Level 9 (60 – 65 cmbd)

scraper

Fire cracked rock (FCR)

potsherd

flake

FCR

clay

charcoal

47LC333

F14 E½

Level 8 (50 – 60 cmbd)

FCR

potsherdpotsherds

large chunk of claydeer bone

½ of a metate

The End…

…really it’s only the beginning!

Meanwhile…back at the lab

All the matrix samples are dried and wait to be floated.

Matrix samples are floated in water and poured through screens. Soil is washed away so that only artifacts, lithics and organic materials remain.

Looking for the little bitty treasures

Everything collected in the screens is placed in cloth and set aside to dry.

Organic matter from the matrix samples is analyzed and classified.

Artifacts are sorted by type, carefully washed and set out to dry before being catalogued and stored.

The Final Stage

When everything has been sorted, classified, counted and a report written the artifacts are rebagged, boxed and stored until they are needed to tell a story of the people from the past.

• Note: This PowerPoint presentation was created by a teacher participating in an ESEA Title II grant-funded project for use in the teachers' classrooms. It reflects the individual’s experience at a particular site and is not intended to accurately reflect what happens on all archaeological investigations around the country or world.

•The teacher participated in professional development activities provided by:

• Mississippi Valley Archaeology Center• University of Wisconsin - La Crosse• 1725 State Street• La Crosse, WI 54601• Web site: http://www.uwlax.edu/mvac/• All material Copyright © 2000-2005 Mississippi Valley

Archaeology Center at the University of Wisconsin - La Crosse