Absolute Dating
Ascertaining the age of an object or artefact with reference to a fixed and specific time scale (e.g. calendar years or radiocarbon years), as opposed to relative dating. Absolute dates are associated with numerical date estimates, so would include all scientific dating methods along with coin dates and other objects that have numerical dates attributed to them by a specialist. Where these dates are derived from scientific dating techniques they are generally presented as a date range with an associated probability curve.
Archaeological Layer/Level
Refers to a horizontal division in an archaeological site, distinguished from one another by differences in artefacts, colour, texture, or other characteristics indicative of changing populations or human activities over time. This would ordinarily be defined during excavation as an extensive deposit, (ie. make-up layer, demolition horizon, etc.) or surface (ie. floor, metalled or cobbled surface, etc.) and may form a ‘nodal’ point in the Matrix.
Architecture
A term used to describe any built or constructed features at an archaeological site. This can refer to buildings, walls, roads, or other constructed elements within the site.
Artefact
An object of material culture that has been created or modified by human activity. In archaeology, artefacts include a wide range of items, from tools, to pottery, to pieces of jewellery. These items provide invaluable insights into the culture, society, economy, and technology of the people who created and used them. They can also be used for dating purposes, to provide relative dating or even absolute dates for the contexts in which they are found.
Construction/Use/Disuse (CUD)
Originally a DUA/MoLA system, high level and broad classification of archaeological groups into which other Subgroups and Groups might fall. ‘Construction’ refers to the initial creation and building of an archaeological feature or entity, ‘Use’ to the period when the entity was functional or operational, and ‘Disuse’ when the entity was no longer in use or abandoned.
Context/Stratigraphic Unit (SU)
Contexts or Stratigraphic Units (SU) are synonymous terms and are the essential elements of a stratigraphic sequence (and any Stratigraphic or ‘Single Context’ Recording System). A stratigraphic sequence is constructed from the building blocks of the recorded stratigraphic units. Two types of stratigraphic units are commonly distinguished as representing distinct stratigraphic activities, either 1. Positive Features (eg. Deposits of material, Architecture etc).. 2. Negative Features (eg. Cuts, Surfaces and Interfaces between deposits). For the purposes of this document we have mostly used the common UK convention in commercial archaeological practice of referring to Contexts.
Cut
In archaeology, a ‘cut’ refers to a context that is the result of a human action that removes (or truncates) other contexts. Cuts can include pits, ditches, and gullies. Cuts are a type of interface and as such have no volume (meaning finds cannot be assigned to them directly); for this reason cuts are usually grouped with their fills, while different fills within cuts may often be separately subgrouped.
Deposit
In archaeology, a ‘deposit’ refers to the material left behind by a human activity, or sometimes natural processes. It can be a single event or the accumulated result of many. Often discussed as being either a layer or a fill, this material can include soil, artefacts, waste products, or other debris.
Depositional (or Stratigraphic) Sequence
A depositional sequence is a series of layers, or strata (and truncations), that have been deposited over time in a specific location. In archaeology, the study of these sequences can reveal important information about the history and chronology of a site. Each layer within a depositional sequence generally corresponds to a particular period or event, with the oldest deposits found at the bottom and the newest at the top, according to the principle of superposition. A depositional sequence can include natural formations, such as sedimentary layers, as well as human-made deposits, such as building ruins or waste dumps. The analysis of depositional sequences forms a key part of stratigraphic excavation and interpretation.
Ecofact
Natural materials, such as plant or animal remains, found in stratigraphic contexts that can provide information about the environment and practices of past societies.
Feature
Fill
A fill is a special subtype of deposit, which specifically refers to the material that is used to fill in a negative or cut feature such as a pit, posthole, ditch, or trench. Fill can include various types of material, such as soil, gravel, waste materials or even artefacts, which can provide important information about the people who created the feature and the nature of their activities.
Finds
Finds is the term used to include all artefacts, building materials, industrial residues, environmental material, biological remains (including human remains) and decay products collected during an excavation (in line with CIfA Standards and guidance 2014).
Finds Specialist
An archaeologist who specialises in the analysis of a particular type of find, (eg. pottery, coins, jewellery, worked flint) which are often further specialised according to period (eg. Medieval pottery as opposed to Prehistoric pottery).
Group
A Group is a stratigraphic entity which combines contexts or stratigraphic units by a range of interpretative criteria (ie. date, location, function, etc.) to create a more substantial and interpretative component of the site, thus simplifying the sequence and, in essence, forms one of the basic units discussed in the stratigraphic narrative.
Harris Matrix – see Matrix
Interface
This term refers to the point of contact between different stratigraphic layers or units. Interfaces can be the result of natural processes such as erosion or deposition, or they can be the result of human activity, such as the construction of a wall or the digging of a pit. In the stratigraphic record, interfaces often represent points of change or transition, and studying them can provide important insights into the sequence and timing of events at an archaeological site. Apart from cuts (which form a special type of interface) interfaces are not commonly numbered as separate contexts, or recorded in the Matrix as a matter of course.
Intrusive
Artefacts from stratigraphically later contexts can find their way into earlier contexts, either by natural processes or through excavation activities, and give inaccurate dating information for the context they are excavated in. These artefacts may be termed intrusive finds.
Land-Use
Land-use refers to a high level of spatial grouping, used on some (usually larger or more complex sites) to offer a spatially and functionally meaningful interpretation of the use of the site in a specific phase or period.
Layer
In archaeology, a layer is a subtype of deposit (or is perhaps for some synonymous with Deposit), which refers to material that was laid down or formed naturally or by human activity in a particular area. Layers are typically horizontal, spreading across a wide area. They can be composed of a variety of materials including soil, silt, organic matter, or even human-made debris. Layers often reflect a specific process of deposition or discrete episodes of activity or occupation and may be associated with particular cultural phases or periods. Each layer in a stratigraphic sequence is usually delineated by changes in colour, texture, or composition that make it distinct from the layers above and below.
Longest Strand (in the Matrix)
Referred to by Roskams (2002) as the ‘Critical Line’ through the Matrix, this refers to the longest continuous sequence of stratigraphic units (contexts, or groups) within a Harris Matrix or Sequence Diagram, which can typically represent the maximum span of (relative) time represented in the stratigraphic sequence. Defining the longest strand is crucial in understanding the chronology and development of a complex stratigraphic sequence, as it technically represents the longest relative duration of occupation or use of the site.
Matrix
(sometimes Stratigraphic Sequence Diagram, or ‘Harris Matrix’ after Dr. Edward Harris)
A diagram visually depicting the sequence of stratigraphic relations between contexts. A matrix diagram shows the stratigraphic sequence between contexts – and from that the diagram can be modified to incorporate depictions of subgroups, groups, and phases.
Material Culture
Material culture refers to the physical objects, resources, and spaces that people use to define their culture. These objects and spaces help to form the basis of societal structures and behaviours. In archaeology, material culture includes items such as artefacts, buildings, monuments, and landscapes that provide evidence about past human activities, beliefs, social structures, and technologies. These items are analysed and interpreted to better understand the culture and lifestyle of a specific group of people in a particular time and place. Material culture can also provide information about trade, migration, interaction, and conflict among different past societies.
Negative Feature
In archaeology, a negative feature refers to a type of feature that is the result of the removal of material, such as a pit, ditch, or posthole (see also: Truncation). These are ‘negative’ because they are primarily defined by the absence of material, rather than its presence.
Nodal Point (in the Matrix)
A nodal point in the Matrix refers to a point where multiple stratigraphic units connect, indicating a significant change or event in the archaeological sequence. It often represents the juncture between different phases or groups of contexts and might physically manifest in the depositional sequence as a surface or a layer extending across a site.
Period
A specific time frame within a larger chronological framework, often characterised by distinctive archaeological, cultural, or historical attributes (with associated start and end dates). Unlike a Phase, a Period is usually defined by an established authority and can span multiple geographic locations. It may be linked to a particular cultural group or civilization (eg. the Roman Period).
Phase
A special kind of stratigraphic grouping which forms a collection of stratigraphic units (contexts) recorded during excavation and interpreted during analysis as having either associated spatiotemporal or spatio-functional attributes that represent a distinct “phase” and duration of activities in the past. Phases often denote a single stage of occupation or use in a specific location and will usually be part of a larger sequence of events. Unlike a Period, a Phase is site-specific and is closely associated with the local stratigraphic sequence; thus Periods should not be seen as Phases, but Phases may certainly correspond to specific Periods.
Positive Feature
In archaeology, a positive feature refers to a type of feature that is formed by the addition or presence of material. Examples could include walls, floors, or mounds. These are ‘positive’ because they are primarily defined by the presence of material, rather than its absence (see also: Negative Feature).
Provenience
The three-dimensional location of an artefact or feature within an archaeological site, sometimes just the context, but often (in the case of special or ‘small’ finds) recorded as a combination of horizontal and vertical measurements.
Relative Dating
Relative dating determines the age of an object in relation to other objects but does not provide a numerical date. It involves methods like stratigraphy, where the lower layers are more ancient than the higher layers, or typology, where the evolution of an artefact type is analysed over time.
Residual
Due to activities in the past, such as digging through earlier layers, artefacts from earlier deposits may be redistributed within later stratigraphic units.
Sequence Diagram (see Matrix)
Seriation
A relative dating technique based on the chronological ordering of artefacts or features according to changes in style or frequency. The assumption behind seriation is that design styles change over time and can be arranged in a predictable sequence. This technique helps archaeologists to infer temporal sequences within an archaeological site or across different sites.
Single Context Recording
A specific stratigraphic recording system, pioneered and developed in London by the DUA and MoLA Museum of London archaeologists, and commonly used in archaeology, where each stratigraphic unit or context in an excavation is recorded and removed individually. Only the stratigraphic (not physical) relationships between contexts are recorded and individual records are linked in this way through the construction of a Matrix. Traditionally within this system, each ‘single context’ is allocated a unique identifier (‘context number’) and will be recorded through the completion of three archival components: a pro forma context sheet, a graphical ‘single context plan’ and an archive photograph (although it should be noted that the shift from analogue towards digital recording and the common use of intra-site GIS has profoundly changed the way in which single contexts are recorded graphically). This method allows for a more detailed and accurate record of the archaeological sequence and is particularly fundamental for understanding the chronology of complex stratigraphy through the relationships between contexts.
Site Excavation ‘Archive’
Small Find
An artefact (or find) that has been individually catalogued due to its particular interest, rarity, significance, or diagnostic features. Small finds typically include items like jewellery, coins, tools, and other portable objects, and they often provide valuable information on specific activities, trade, and cultural affiliations in the archaeological context.
Spot Date
A date provided on a particular (ideally well-stratified) object which can often be used during excavations to give an initial indication of a date for a context in which that object has been found.
Strands (of the Matrix):
Strands in a Matrix refer to distinct sequences of stratigraphic units that represent continuous or linked series of stratigraphic contexts, which extend from underlying or overlying Nodal Points.
Strata
Layers or horizons within an archaeological site, representing distinct episodes or periods of activity. Each individual layer is referred to as a “stratum.” Strata can contain artefacts or other evidence that help to date and interpret the activities that occurred within that layer. The deeper the stratum, the earlier the period it usually represents.
Stratigraphic Narrative
Commonly stratigraphic narratives consist of two key components: A detailed and highly descriptive technical summary of the depositional sequence and a more synthetic and interpretative phased discussion of the sequence. There is a wide variation of practice and style of stratigraphic narrative.
Stratigraphic Recording
A method of recording and interpreting an archaeological site based on the principles of stratigraphy, which gives primacy of documentation to discrete stratigraphic units or contexts. It involves recording (and excavating) the site’s strata (or layers) and other features, including cuts, in the order of their deposition, from the most recent (topmost) to the earliest (bottommost). Each stratigraphic unit is documented, including its relationship with adjacent sequential units, allowing for the reconstruction of the site’s history of deposition and use.
Subgroup
A subgroup is a set of contexts that are interpreted together to be the result of a singular event (i.e. an activity) in the past that will have one applicable timespan (eg. a pit and its primary fill; or a construction cut, wall, and construction cut backfill).
Subphase
A subphase is usually identified as a distinctly interpreted spatiotemporal or spatio-functional entity within an already identified phase. This would normally be very localised (perhaps within a structure or specific trench/area of excavation).
Surface
An archaeological surface refers to a distinct layer or plane, typically horizontal, that is the result of human activity or natural processes. This may include living surfaces, occupation floors, roadways, or even the topmost layer of a deposit. A surface, and the material culture directly associated with it (ie. placed upon, or strewn across it) may hold important clues about past activities, use of space, or chronological changes, making it a significant element for interpreting the stratigraphic record. Unlike Cuts (which are recorded as a special type of intrusive interface) horizontal surfaces (Interfaces) are not commonly separately numbered in the Matrix or Stratigraphic Recording Systems (such as Single Context Recording).
Survey
Text Section
Truncation
In an archaeological context, truncation refers to the process of a stratigraphic unit being cut into or worn away by subsequent human or natural actions. Whilst truncations may be anthropogenic, the word has a broader application and can occur naturally or in taphonomic processes (e.g., erosion, animal burrows), where a ‘cut event’ would tend to imply human activity in an archaeological sense. Truncation can result in the loss of archaeological information, as older stratigraphic units are removed or disturbed. Truncation can also often be recognised as ‘negative’ stratigraphic features and might include cuts, holes, scoured surfaces, or erosion events. There is not necessarily a consensus on when best to apply the terms ‘truncation’ and ‘cut’ and they are often used interchangeably.
Typology
A relative dating technique articulated around the systematic classification and study of artefacts based on their characteristics, such as shape, size, decoration, material, and method of manufacture. Typologies are often used to identify and date archaeological artefacts, establish cultural affiliations, and understand technological and stylistic changes over time.