Excavation methods vary according to which dimension of the past an archaeologist chooses to study. This technique requires archaeologists to uncover a site layer by layer until reaching the level of the desired time period. Alternately, an archaeologist seeking to understand the progression of time at a site would probably employ a grid excavation . Baulks allow archaeologists to examine a site's general stratigraphy and are later removed to reveal whatever might lie within them. Researchers use more intrusive excavation methods when a site will be obstructed or destroyed by some form of modern development, such as a shopping center.
Researchers gather two very different sets of information during the course of any excavation.
They can examine tangible findings, such as artifacts and the remains of plants, animals, and humans, well after an excavation has ended. However, excavation destroys contextual features, such as building remains, as they are uncovered. To preserve vital information about these remains, archaeologists painstakingly catalog every nuance of a site through volumes of photographs and drawings.