excavation methods

Vertical excavation proceeds downward through successive deposits. By recording each layer and its finds, archaeologists establish a relative sequence of occupation and identify changes from one period to another. Hence option A is correct. Mapping one building in plan is more closely associated with horizontal exposure, while collecting surface objects or levelling the site does not reveal chronological layering.

A trial trench is a limited excavation opened to sample the deposits of a site before committing resources to a larger project. It can reveal the depth, sequence, preservation, and approximate archaeological potential of the layers, helping archaeologists plan the next stage. Thus option A is correct. It is not intended to excavate an entire city, repair artefacts, or construct a museum.

During a surface survey, archaeologists systematically inspect the ground and record visible artefacts, pottery scatters, bricks, stone fragments, mounds, walls, and other structural traces. These patterns can suggest the location and extent of buried occupation even before excavation begins. Therefore option A is correct. The other choices concern unrelated environmental, economic, or zoological information.

A levelling instrument is used to compare the elevations of different points and to establish changes in ground height, making it possible to map the slope and relief of an archaeological site. Consequently, option A is correct. A soft brush cleans delicate finds, a sieve separates small materials from soil, and a hammer is used for limited excavation or geological work; none is the proper surveying instrument here.

A datum point is a fixed, recorded reference used as the common basis for measuring the position, depth, and elevation of excavation units and finds. Using one reference improves accuracy and allows observations from different areas or days to be compared. Thus option A is correct. A datum does not clean artefacts, independently date soil, or indicate that a trench should be closed.

A context number is assigned to a distinct archaeological unit, such as a deposit, layer, pit, wall, floor, or other recognisable feature. It provides a consistent way to record the unit and associate its finds, relationships, and observations in the site archive. Therefore option A is correct. Numbering is not restricted by an object’s material, human remains, or whether a pot is complete.

Cultural layers are deposits created or substantially altered by people, such as floors, occupation debris, ash, broken pottery, and construction material. Natural layers form through processes such as flooding, wind deposition, soil development, or erosion without being produced by human occupation. Therefore option A is correct; the distinction is about origin, not that one layer is always modern or contains a particular material.

The governing concept is stratigraphy, which studies the sequence and relationships of deposits. When a later pit cuts an older layer, the cut disturbs the earlier deposit, while the pit fill belongs to a later activity. Therefore, the contexts become complex and must be recorded separately. Option A is correct; B and C wrongly change the dates of all objects, while D exaggerates the effect because stratigraphy can still be analysed.

In archaeological stratigraphy, a pit is a later cut and its fill is the material deposited after or during the cutting event. Objects inside that fill usually relate to the activity or process that filled the pit, although some may have been redeposited. Thus A is the best answer. B confuses the original layer with the later fill, and C and D have no contextual basis.

Archaeologists examine soil colour together with texture, composition, inclusions and boundaries. A visible colour change may mark a separate deposit, a floor, a pit fill or an activity area, so it helps define contexts during excavation. Option A is correct, but colour alone does not prove a date or identify gold. Rain is only one possible cause, not the only explanation.

Soil texture records whether a deposit is sandy, clayey, silty, compact, loose or mixed with ash and other inclusions. These properties help archaeologists infer how the deposit formed, such as through natural accumulation, construction, dumping or burning, and may suggest activities at the location. Therefore A is correct; texture cannot reveal market price, modern ownership or script language.

An ash layer is evidence of burning, but its interpretation depends on location, thickness, composition, associated objects and spatial extent. A small concentrated deposit may indicate a hearth, whereas a broader layer could reflect a larger fire or industrial activity. Thus A is the only suitable option. It should not automatically be labelled as destruction, and the other choices do not normally explain ash.

The governing archaeological principle is contextual analysis. When a burnt layer is discovered, the archaeologist should record its extent, depth, position, relationship with nearby deposits and associated objects such as ash, charcoal, pottery or structures. This helps distinguish a local hearth from a wider fire or destruction event. A is correct; colour alone is insufficient, while the modern name and village population do not interpret the deposit.

Human remains must be treated as archaeological evidence in their complete context. The team should map and photograph the skeleton, record its orientation, depth, relationship to the grave and associated objects, and then have trained specialists recover it carefully. A is correct because position can reveal burial practices. Immediate lifting, discarding soil or keeping only the skull destroys valuable evidence.

Careful sieving separates small materials that may be missed during hand excavation, including beads, teeth, tiny bones, charcoal and other grave goods. These finds can clarify burial customs, diet, health or the identity and activities of the buried person when studied with the complete context. Therefore A is correct. Sieving does not change soil colour, automatically determine age or reduce trench depth.

Animal bones are important archaeozoological evidence. Their species, age, body part, condition and cut or burning marks can reveal what people ate, which animals they hunted or kept, and how animals were processed. Separate collection preserves provenience and prevents samples from different contexts being mixed. Thus A is correct; the other options are not valid archaeological purposes.

Charred seeds are valuable archaeobotanical remains because burning can preserve them even when unburnt plant material decays. Identification of their species and context can reveal cultivated crops, gathered plants, food habits, storage and agricultural practices. Therefore A is correct. Seeds do not directly give the date of metal objects or wall dimensions, and they were not necessarily used only as fuel.

The governing concept is flotation-based recovery in archaeological excavation. Soil is mixed with water, and light organic materials such as seeds, grains, charcoal and small plant remains float while heavier soil and stones sink. The floating fraction can then be collected and studied by archaeobotanists. Therefore option A is correct; bricks, walls and heavy metal tools would not normally be recovered by this method because they sink.

The governing conservation principle is that waterlogged wood must be dried gradually and under controlled conditions. Water supports the weakened cellular structure of buried wood; if it evaporates suddenly, the cells collapse, causing shrinkage, warping and cracks. Option A is therefore correct. Wood cannot turn into metal, its weight does not increase for this reason, and drying does not make its chronological age younger.

The governing concept is archaeological conservation. A metal object may carry corrosion products and may deteriorate when exposed to oxygen, moisture, salts or careless cleaning. Specialists therefore examine it, remove harmful deposits safely and stabilize it in a controlled environment. Option A is correct. Strong acid can damage the object, direct sunlight and moisture changes can accelerate deterioration, and repainting would conceal evidence rather than conserve it.

The governing principle is that cleaning must not destroy archaeological evidence. Before washing a pottery sherd, an excavator should inspect it for paint, inscriptions, impressions, soot, food crusts, mineral deposits or other fragile residues and record them when necessary. Option A is correct because water or brushing may remove such evidence. Market price, modern use and weight alone do not determine whether washing is safe.

The governing concept is pottery reconstruction and analysis. When matching sherds are joined, archaeologists can estimate the original vessel’s shape, rim and base, capacity, manufacturing technique and sometimes its function. These details may also help compare cultural or chronological traditions. Option A is correct. Joining pottery alone cannot reveal a modern site boundary, automatically identify a king or establish the direction of a river.

The governing concept is typological classification in archaeology. Researchers compare a pottery vessel’s shape, fabric or clay composition, colour, surface treatment, firing quality and decoration. Repeated combinations of these features can indicate technological traditions, cultural differences or chronological phases. Option A is correct because it combines the principal observable criteria. Weight alone is insufficient, while a site name or modern price is not a physical basis for pottery classification.

The governing concept is systematic archaeological sampling. Selected soil, seeds, charcoal, bones and other materials can be examined for evidence about environment, diet, agriculture, technology and chronology. Sampling makes scientific testing possible while preserving a documented record of the excavated context. Option A is correct. Sampling is not decoration, disposal of finds or simply a way to reduce the depth of a trench.

The governing concept is radiocarbon, or Carbon-14, dating. Living organisms exchange carbon, including a small amount of radioactive Carbon-14; after death, the Carbon-14 gradually decays. Measuring the remaining amount can estimate the age of suitable organic material within the method’s usable range. Option A is correct because wood, seeds and bone are organic. Brick, stone and copper are inorganic and are not dated directly by this method.