The scientific study of human behavior in the past through the excavation, examination, and interpretation of sites and artifacts.

Archaeological Excavation

Scientifically controlled removal of earth and artifacts by an archaeologist and/or archaeological team.


Any object made, used, or modified by human action. Artifacts are distinct from other types of material culture found on archaeological sites, like features.

Auger Test

Also called coring and sometimes posthole testing, this simple procedure uses a long and thin handheld drill or probe like tool to collect a vertical sample of earth on archaeological sites. The purpose of the test is to examine subsurface stratigraphy without or before excavation. The information gleaned from auger testing can help guide fieldwork.


A large, human-operated excavating machine attached with a hydraulic bucket, or digger, typically used during construction activities. Archaeologists sometimes utilize these machines to quickly remove unwanted soils and/or oversized materials from sites before and during archaeological excavations.


Materials used to provide stability, levelling, and/or insulation during the construction of floors for buildings and other structures.

Belgian Blocks

Rectangular, tooled granite paving stones sometimes referred to as cobbles or cobblestones typical of 19th-century New York City’s sidewalks and streets. Belgian Blocks are a specific type of building material, while "cobbles" is a catch-all term that can also mean rocks naturally smoothed by water.  


Dense, sedimentary rock native to New York and surrounding areas. Bluestone slabs were used to pave New York City sidewalks in the 19th century. 

Bore Size (Smoking Pipe)

Clay smoking pipes are some of the most common artifacts found on historical sites and are highly dateable, making them particularly important to archaeologists. The basic anatomy of a pipe includes a bowl for holding tobacco and a stem to draw the smoke through. Bore size refers to the dimensions of the hole inside of the pipe stem. Stem bores are usually measured in imperial 64ths of an inch, with size generally decreasing over time. The age of a pipe is usually expressed as a time range that reflects the dates of manufacture for that particular type of pipe. Archaeologists also consider form, style, finish, maker's marks, decoration, and manufacturing technique when dating pipes to further refine production dates.  

Builder's Trench

A long and thin hole dug into the earth to assist in the laying down of building or structure foundations during construction. In time's past, builder's trenches were often excavated by hand and had to be wide enough to accommodate both workers and construction materials. Builder's trenches are great resources for archaeologists because they help to date the buildings and structures found on archaeological sites. 

Catalog Number

A unique identification number assigned to artifacts found during archaeological excavations. Archaeological sites are often complex and complicated spaces in which numerous artifacts and contexts are encountered. Catalog numbers help archaeologists keep track of the spatial data for each and every artifact. Improper recordation can lead to faulty analyses and interpretations. 


A waterproof shaft feature -- so called because of their below-ground shape -- for storing rainwater common in New York City backyards before the advent of modern utilities. Once utilities were introduced to New York City beginning in the mid-19th century, cisterns became obsolete and transitioned into convenient receptacles for household trash. Cisterns often provide exceptional information to archaeologists as they can be attributed to a single household, family, or time period.


Archaeologists scientifically assess the ground by digging stratigraphically, or in precise levels based on observable differences in the layers of the earth. Context is the precise positioning of artifacts and features in space and time and their resultant associations with each other. Context can also be called “provenience”.


A physical, fixed point from which to take standardized depth measurements on an archaeological site. 


Often synonymous with layer, level, horizon, and strata, deposits can also refer to distinct areas of artifact and/or soil concentrations that resulted from specific cultural or natural events. This is different from stratigraphic layers, which develop slowly and are the result of large-scale geological processes.


Vertical measurements taken off of a local, fixed point on an archaeological site. Fixed points can be unit datums or even the ground or excavation surface. Depth is different from elevation, which is the height above or below an official point, like sea level. 

Diagnostic Artifacts

An artifact that can be attributed to a specific time period or date range. 


A natural or culture event or sequence of events that dislodges and disrupts intact stratigraphical layers. While artifacts found in disturbed layers are analyzed differently than those from intact layers, disturbances are important because they provide information about the history of the area being studied.  


Stacking stones on top of one another to create a wall without the use of mortar or other sealing compounds.


Organic materials on archaeological sites that were not made or modified by humans. Examples of ecofacts include animal bones, plant remains, pollen, and charcoal. Ecofacts are important to archaeologists because they can provide important information about past human behavior and environmental conditions. 


Human waste. 

Excavation Unit

A standardized pit, trench, cut, or hole created for the scientific investigation of archaeological sites. During the Stadt Huys project, excavation units were referred to as “test cuts”.  


Animal remains like bone and shell found on archaeological sites. The branch of archaeology that specializes in the analysis of animal remains is called zooarchaeology.  


Structural or physical elements made or modified by humans that cannot be removed from an archaeological site intact. Features include large-scale structural remains like foundations, earthworks, or embankments, but also smaller-scale elements like postholes, burned earth, collections of ash and charcoal, hearths, pits, and floors.  


Material which is (a) either deliberately brought into a location to raise the ground level, to level irregular topography, or to make new land; (b) construction/demolition debris which serves as the basis for later construction; or (c) deposits that can form the foundation for historic archaeological sites. 


Footings (so called because they stick out like a foot) form the bottom part of structural foundations. They are critical in distributing weight evenly to prevent buildings from sinking into the ground.    


The main structural support for a building. Intended to anchor structures into place, foundations are often found below ground level. Common building materials include brick, stone, and, beginning in the late-19th/early-20th century, concrete. 

In situ

A Latin term that means, “in the original place.” Archaeologists often use this term to describe artifacts or elements that are found in the exact location that they were originally deposited or built.  


A term denoting a thin, ephemeral layer of soil within or between larger, established strata on archaeological sites. Lens can also be used to mean a distinct deposit contained within a larger stratigraphic layer.  


The standard stratigraphic unit excavated by archaeologists. Levels are different from layers. Layers are discrete strata that archaeologists dig by level. Levels are often arbitrary, meaning that archaeologists predetermine a set amount of earth to be dug (usually 4-inches or 10-cm). Levels can be human-made, like fill, or natural, meaning that their depth follows the earth’s geology. Arbitrary and natural levels can occur on the same site. While levels are important when digging, their information is aggregated together by strata when analyzing and interpreting the results. 

Living Surface

Living surfaces are special areas on archaeological sites because they reveal evidence of human activity in contained areas and from particular periods of time. The activities themselves may be discrete, meaning that they reflect specific occupations or actions in the past. The artifacts that are recovered from these surfaces are of great value because of their exceptional spatial and temporal control. Different from other types of floors like wood or brick, living surfaces are often made of dirt and are distinguishable by their compaction, which is likely created by the constant physical action of humans and animals (walking, sitting, sweeping, e.g.).


The illegal act of taking artifacts without permission from archaeological sites to sell or keep. Unlike archaeologists, looters do not document where the artifacts they took were found. Without this information, archaeologists cannot properly analyze and interpret the sites they are working on. Archaeological sites are nonrenewable resources, meaning that they are unique places that shed light on the human past. Once destroyed, this information is lost forever.  


A tract of land that forms the basic unit for zoning regulations in the city.  


The physical place within the earth where archeological deposits and artifacts are located. 


Archaeologists in the field or the laboratory sometimes notice that pieces of glass, ceramic, or other material found separately actually fit together, or mend. Mending is thus the process of reassembling whole or nearly whole vessels from sherds found during excavation, much like a puzzle. If the sherds were found across the site and not concentrated in one stratigraphic layer, the process is called "cross-mending".  


A durable and workable paste that is used to fasten building materials like bricks and stones together. Different than cement, mortar is made out of sand, binding agents, and water. It also hardens as it sets. Mortar has been used for thousands of years and is still produced today.  

Munsell Color System

A color-matching system used to uniformly record soil colors in the field. Munsell colors are distinguished by Hue, Value, and Chroma and are written thusly: 10YR 5/4 yellowish brown.  


A collection of soil or other matter that lays atop the regular surface of a test pit or excavation unit. Though overburdens can provide important information about site histories, they are often removed before archaeological testing begins. 

Plan and Profile Drawings

Plan and profile diagrams are to-scale illustrations of the physical elements of an archaeological site. To-scale means that the object being depicted keeps its true measurements, but in a smaller size. To accomplish this, archaeologists use graph paper and tools like line levels, plumb bobs, and measuring tapes and rulers. Both types of drawings are important in the interpretation and analyses of sites and artifacts.  

A plan drawing is a graphic illustration of the horizontal elements of a site. A horizontal perspective can be thought of as a bird’s eye view. Horizontal viewpoints are two-dimensional depictions of a flat plane as seen from above. Street maps are a classic example. Plan drawings are useful tools because they can (1) portray spatial relationships between excavation units, features, and landscape; and (2) record vital physical information about features. Archaeology necessarily destroys the things that it studies. Plan drawings are thus an important record of resources that may no longer exist.

Profile drawings depict the vertical elements of an excavation unit. Vertical can be thought of as an up-down or side view perspective, like depicting the face of a building. The purpose of a profile drawing is to accurately show the stratigraphy of an excavation unit through the illustration of one or more unit walls. Profile drawings include anything that contributes to the physical story of the excavation unit, like features, artifacts, rocks, and tree roots. Archaeologists use a fixed line, or datum, to measure the depths of every layer and element. Color (using the Munsell Color System), texture, and composition are then recorded for each layer. 

Posthole (Postmold)

Archaeological features containing the remains of (usually wooden) posts for fences, palisades, or other enclosures or structures.  Postholes can contain remnants of the original post, though they often appear as soil stains of a different color or texture than the surrounding natural soils.


Non-mechanical outdoor toilets often placed in the backyard. These types of shaft features -- so called because of their below-ground shape -- were the primary way that early New Yorkers disposed of human waste before the advent of modern utilities. Privies are essentially large holes dug into the ground and lined with brick, stone, and/or wood, or left unlined. Privies were not connected to sewers and had to be periodically cleaned by hand. Once utilities were introduced to New York City beginning in the mid-19th century, privies became obsolete and transitioned into convenient receptacles for household trash. Privies provide exceptional information about diet, disease, sanitation, and disposal practices and are especially important as they can often be attributed to a single household, family, or time period.  


Stratigraphic layers and/or deposits disturbed by earth-moving activities and subsequently reinserted in the same or similar location. Redeposited soils are considered disturbed because their original contexts have been destroyed. However, redeposition can tell archaeologists a lot about the history of the sites they are studying. 


Physical remains like artifacts, features, sites, and associated documentation found through archaeological methods that reveal information about past human activity and behavior. 


Screening is an essential task archaeologists perform during excavations to collect artifacts from the soil. Though it can come in many forms, a screen is basically a wooden box with 1/4- to 1/2-inch wire mesh serving as the bottom. The person working the screen will pour dirt from excavation units into the box and agitate it to force the soil through the mesh openings, leaving the larger artifacts and ecofacts behind. Archaeologists then collect these materials for later analysis.

Screening can be dry or wet. Wet screening uses the aid of water to clear off soils from artifacts.  


Natural stratigraphic layers are made up of either soils or sediments. These two types of layers are scientifically distinct from one another because they develop in very different ways. Sediments are rock and/or mineral particles that move from one location to another by processes of erosion, like water, wind, gravity, or ice. These erosive particles then collect in particular places over time and become distinct stratigraphic layers.  

Shaft Features

Privies, cisterns, wells, and other waste and water features that were common in New York City backyards until the introduction of modern utilities in the mid- to late-19th century. Shaft features are often referred to as outbuildings.  


A piece of broken pottery or ceramic found on an archaeological site.  


A distinct spatial clustering of materials representing past human activity. It may also connote a project area.  


Unlike sediments, soils develop in place (pedogenesis) and are comprised of organic materials capable of supporting plants. Soils are differentiated into horizons based on physical characteristics. 

Soil Horizon

From the surface downward, the four most common horizons are: O, A, B, and C. The O horizon is the thin layer of fresh and decaying plant residue on the surface. The A horizon is below the O and contains both organic and mineral material. The B horizon typically contains less organic matter, making it redder or browner than the above A horizon. The C horizon is the oldest of the four horizons and does not often contain organic materials.  


In archaeology, the word slope is used to describe land that is at an incline or a decline. Another way to think of slope is as a surface that is angled relative to the horizon, or that has one end higher than the other. The sides of hills and pitched roofs are good examples. 


The earth is made up of a series of sediment and/or soil layers that have developed over space and time. Archaeologists examine these various layers, or strata, for evidence of human activity. Archaeologists call this type of analysis stratigraphy, which refers to the study and reconstruction of the temporal and spatial relationships between the earth’s strata. Stratigraphy is one of the most important analyses that archaeologists undertake during excavation because it allows for a more in-depth interpretation of artifacts (see “context”).    

Strata (Stratum)

Can also be called layers, horizons, and deposits. Strata are the natural layers in the earth made up of sediments or soils that are differentiated by observable physical attributes, like texture, color, and composition. Archaeologists use the Munsell Color System to uniformly record stratigraphic colors. It is important to note that human-modified layers or deposits can also be found in archaeological excavations (see “fill”).  


A stratum that has no material culture within it. 


A natural stratigraphic layer that underlies all cultural layers. The subsoil is considered too old for human habitation. Once reached, an archaeological excavation is often considered complete.  

Terminus Post Quem (TPQ)

The earliest date that something could have been deposited on an archaeological site. For instance, an intact stratigraphic layer found with a coin dating to 1815 could not have been deposited before that date because the coin would not have existed. However, the layer could have been deposited at any point after 1815. TPQ is not intended to give the exact date/s of layers, but rather to help build a general understanding of the site’s chronology.  

Terminus Ante Quem (TAQ)

The latest date that something could have been deposited on an archaeological site. While not as commonly used as TPQ, TAQs can be determined under the right conditions. For instance, deposits that are located beneath floors, walls, or other structural elements for which the dates of construction are known. As long as the floor is not disturbed, the deposits laying underneath it could not have been set down after the floor was built. TAQ is not intended to give the exact date/s of layers, but rather to help build a general understanding of the site’s chronology.   


In archaeology, truncated usually refers to the removal of the upper portion of a stratigraphic layer or deposit. Though the remaining layer may not be disturbed or mixed up, it is important to note that its stratigraphical and archaeological information is incomplete.   


Water, sewers, trash, gas, electricity, telephone lines, and other essential goods, services, or infrastructure. Each type of utility has its own history and was introduced to consumers at different times. Archaeologists often find evidence of the structures and strategies early New Yorkers used to get rid of waste, store water, and perform other duties before the advent of modern utilities.  

Water Table

The depth at which below-ground excavations hit the natural water level in the area. 


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