Shovel test pit
Encyclopedia
A shovel test pit is a standard method for Phase I of an Archaeological survey. It is usually a part of the CRM
methodology
and a popular form of rapid archaeological survey in the United States of America and Canada
.
It designates a series of (c. 0.50 m or less) test holes, usually dug out by a shovel
(hence the name) in order to determine whether the soil contains any cultural remains that are not visible on the surface. The soil is sifted or screened through 1/4" or 6 mm wire mesh to recover the artifacts.
STPs will often be laid out over the project area in a grid-like fashion or in a consistently spaced line, creating a fairly systematic survey. Therefore, after the holes have been dug, one may map artifact densities over the project area, pinpointing the locations of possible sites where further investigation may be necessary. The interval
at which the STPs are placed varies considerably and, in CRM
at least, is sometimes prescribed by state
regulations (in the U.S.
) or is determined by the conditions in the field. The usual space between two STPs is 10 m or more but it can be considerably less (e.g., 1 m). The current standards in the United States is 30m or less. The depth of an STP depends on the depth at which either the bedrock or the sterile
subsoil
is found.
The form of STP may vary from region to region and even within regions by company/organization. Common forms include circular and square shaped. Circular STP often have cylindrical to "bullet" (i.e., cylinder with short inverted conical base) shaped profiles and range from 30 cm to 50 cm diameter. Square STPs are typically about 50 cm, but some locations prefer other sizes (e.g., 40 cm). Unusual and unusually ineffective variants include circular (30 to 50 cm diameter) STP with truncated conical profiles.
Depth of STP excavation also varies widely and is often dependent upon local soil types and expected maximum depth of sites. Typically this ranges from 30 cm to 1.0 m. A second factor is mechanical, in that excavation is limited by the tools and techniques used (i.e., shovel versus trowel). Typically STP are excavated to a maximum average of 1.0 m, although it is possible to excavate somewhat deeper (1.25 to 1.5 m) dependent upon the excavator and the tools available. STP can be combined with other techniques and tools (augers, corers) to extend the maximum depth of effective testing beyond 1.5 m.
Cultural resources management
In the broadest sense, Cultural Resources Management is the vocation and practice of managing cultural resources, such as the arts and heritage. It incorporates Cultural Heritage Management which is concerned with traditional and historic culture. It also delves into the material culture of...
methodology
Methodology
Methodology is generally a guideline for solving a problem, with specificcomponents such as phases, tasks, methods, techniques and tools . It can be defined also as follows:...
and a popular form of rapid archaeological survey in the United States of America and Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
.
It designates a series of (c. 0.50 m or less) test holes, usually dug out by a shovel
Shovel
A shovel is a tool for digging, lifting, and moving bulk materials, such as soil, coal, gravel, snow, sand, or ore. Shovels are extremely common tools that are used extensively in agriculture, construction, and gardening....
(hence the name) in order to determine whether the soil contains any cultural remains that are not visible on the surface. The soil is sifted or screened through 1/4" or 6 mm wire mesh to recover the artifacts.
STPs will often be laid out over the project area in a grid-like fashion or in a consistently spaced line, creating a fairly systematic survey. Therefore, after the holes have been dug, one may map artifact densities over the project area, pinpointing the locations of possible sites where further investigation may be necessary. The interval
Interval
Interval may refer to:* Interval , a range of numbers * Interval measurements or interval variables in statistics is a level of measurement...
at which the STPs are placed varies considerably and, in CRM
Cultural resources management
In the broadest sense, Cultural Resources Management is the vocation and practice of managing cultural resources, such as the arts and heritage. It incorporates Cultural Heritage Management which is concerned with traditional and historic culture. It also delves into the material culture of...
at least, is sometimes prescribed by state
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...
regulations (in the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
) or is determined by the conditions in the field. The usual space between two STPs is 10 m or more but it can be considerably less (e.g., 1 m). The current standards in the United States is 30m or less. The depth of an STP depends on the depth at which either the bedrock or the sterile
Sterile deposit
In archaeology, a sterile deposit is a geological stratum that lacks any materials of archaeological significance. That is, there are no artifacts, ecofacts, or features present....
subsoil
Subsoil
Subsoil, or substrata, is the layer of soil under the topsoil on the surface of the ground. The subsoil may include substances such as clay and/or sand that has only been partially broken down by air, sunlight, water, wind etc., to produce true soil...
is found.
The form of STP may vary from region to region and even within regions by company/organization. Common forms include circular and square shaped. Circular STP often have cylindrical to "bullet" (i.e., cylinder with short inverted conical base) shaped profiles and range from 30 cm to 50 cm diameter. Square STPs are typically about 50 cm, but some locations prefer other sizes (e.g., 40 cm). Unusual and unusually ineffective variants include circular (30 to 50 cm diameter) STP with truncated conical profiles.
Depth of STP excavation also varies widely and is often dependent upon local soil types and expected maximum depth of sites. Typically this ranges from 30 cm to 1.0 m. A second factor is mechanical, in that excavation is limited by the tools and techniques used (i.e., shovel versus trowel). Typically STP are excavated to a maximum average of 1.0 m, although it is possible to excavate somewhat deeper (1.25 to 1.5 m) dependent upon the excavator and the tools available. STP can be combined with other techniques and tools (augers, corers) to extend the maximum depth of effective testing beyond 1.5 m.