Archaeology Layers and Positions

 
It is very important to record the position of all the objects that are found. The vertical position of an object, as defined by the layer in the earth, or strata, where it is found reveals its date or at least it relations to what came before and after it. Archaeologists carefully remove earth layer by layer when they are excavating so they can determine the date or period of objects and not mix them up with objects from other periods.

 The strata are often look like the layers of a layer cake, with the oldest layers being the ones that are the deepest in the earth. Each layer and the locations of artifacts are carefully measured, often with surveying equipment. The layers can be dated by using the dating methods listed below.

 Many ancient buildings were constructed of mud brick or stone. Over time, walls of these structures tended to weaken and collapse, often due to rain or an attack, and the ruins were leveled off before a new structure was raised. Each time a building collapsed and a new one was built on top of it and a new layer of strata was created. Over centuries many layers are piled on top of one another and a mound is created.

 The horizontal position of an object and it locations in relation to other objects often give clues to what the object is used for. The locations of each significant object found are recorded using a grid system that usually can be overlaid on the excavation site. These days measurements can be done with lasers and excavation records and survey data can quickly be transferred to computer to create a three'dimensional model of excavated objects and their positions.

Stratification and Commerce

 David Silverman of Reed College wrote: “The distribution of pottery types into particular layers of an excavation is not always perfect. Sometimes a single layer contains pottery from two different periods. Come back for a second to the hypothetical example of the Bell-bottom people versus the Saggers. Suppose you found a few pairs of bell-bottoms among the baggy shorts. Since they are relatively rare compared to the shorts, we can posit that a few people in the 1990's liked to wear clothes from the 1960's. The bell-bottoms might actually date back to the 1960's; the analogous pottery item in this case would be called an heirloom. Or, the bell-bottoms might have been made in the 1990's in a deliberate effort to achieve that 1960's look; the pot in this case would be called archaizing. [Source: David Silverman, Reed College, Classics 373 ~ History 393 Class ^*^]

 “What if, on a level which had primarily bell-bottoms, some baggy shorts showed up? Or, in pottery terms, what if you find traces of a late style in a layer which the majority of the evidence suggests is early? This situation is much more rare than the previous one. There would be only two possible explanations. One, that the stratification of the site, the levels, had been disturbed at some time between the inhabitation of the area and the excavation. This happens when someone has dug through the levels and jumbled up their contents. If it is established that the levels were undisturbed, that means that the previously existing ruling chronological scheme, which maintained that no one was wearing baggy shorts in the 1960's, was wrong and has to be revised. Archaeologists tend to have a hostile reaction when someone claims that a particular pottery chronology needs revision."*^

 “In addition to knowing the date of manufacture of a particular piece of pottery, it is often also possible to tell where it was made. This in turn allows us to deduce with what other peoples a particular people might have had contact, especially commerce. Goods commonly traded in antiquity, such as wine and oil, were routinely transported in large earthen vessels, called storage amphoras. Sometimes, too, the vessel itself is the import product; this is true in the case of some elaborately decorated pottery (called fine ware, as opposed to coarse ware such as storage amphoras)." ^*^

Stone Tool Terminology

 
Louis LeakeyStone tools are the oldest surviving type of tool made by hominins, our early human ancestors. It is likely that bone and wooden tools were used quite early, but organic materials deteriorates with time and doesn't survive like stone. Archaeologists sometimes use the term 'lithics' to refer to all artifacts made of stone. [Source: K. Kris Hirst, Thoughtco.com, March 8, 2017 ==]

 Artifacts (also spelled artefacts) are objects or remainders of objects, which were created, adapted, or used by humans. The word artifact can refer to almost anything found at an archaeological site, including andscape patterns, trace elements attached to potsherds. All stone tools and pieces of stone tools are artifacts. ==

 Geofacts are pieces of stone that looks as if they can be used as tools, with seemingly human-made edges, that have been created naturally by erosion or being broken and have not been shaped, modified or purposely broken by humans or hominins. Objects that are products of human behaviors are artifacts. Geofacts are produced by natural forces. Telling the different between artifacts and geofacts can often be difficult. ==

 An assemblage or haul refers to the entire collection of artifacts recovered from a single site. Material culture is used in archaeology and other anthropology-related fields to refer to all the corporeal, tangible objects that are created, used, kept and left behind by past and present cultures. ==

Working on an Archaeological Dig

 Describing his experience, working as a volunteer at an Early Bronze Age site in Mitrou, a small island in southern Greece, Stefan Beck wrote in the Wall Street Journal, “It was before six on my first morning...I found myself hauling potsherds, pickaxes, shovels and computers from a gecko-infested “apotheke” (warehouse) to a big orange truck parked outside. When the truck was full, we headed off, a police escort alongside to protect us from hijackers---that is to say, from antiquities smugglers eager for our loot. We then unloaded it at a new, more spacious apotheke."

 “The second day was spent removing backfill at the site. At the end of each season of exploration, the archaeologists put a tarp over the site and then covered it with soil to protect artifacts from the ravages of weather...here I began to grasp how little of archaeology is strictly “digging." As the dirt came out these scientists paid careful attention to the profile of the tarp beneath it; even a after a year, the trench supervisor knew what lay under every contour---a cist tomb, a fragment of wall...The site operated as methodically as an ant arm and with every bit as much purpose."

 “As the days wore on---and my back wore out---I became more impressed by the range of knowledge that mere “digging” required. Archaeology cuts across the shallow trench that divided the hard sciences from the humanities. To get the full value...requires some knowledge of technology, history, language (both ancient and modern), classical literature, zoology , botany, geology and art...And how can I forget the charming field of mortuary analysis."

Pottery Analysis

 Almost every archaeological site yields thousands of pieces of broken pottery known as pottery shards, or potsherds. Because pottery was cheap and easy to make, ancient people thought nothing of throwing it away. Archaeologists are adept at deciphering pottery shards. They can often date a site, gage its level of sophistication and establish trading patterns solely by examining pottery shards.

There are tables and guides that archaeologists can refer to identify potsherds. Different kinds of pottery can be differentiated by the designs, pottery making process and the composition of clay, glazes and pigments used to make it. Large data bases of over 7,000 kinds of pottery from different ages and different sites around the Mediterranean alone cane be used to identify the date and origin of the objects. The analysis is based on the type of clay used, pottery type and ornamentation.

 Pottery can be dated measuring the effects of radiation via thermolumiscence, by carbon dating food remains or dating the sediments of the layers in which the pottery was found. A “clay atlas” has been created for “fingerprinting” pottery for 35 trace elements. This atlas is especially useful with small pottery shards.

Importance of Pottery

 David Silverman of Reed College wrote: “One material which totally defies the corrosive effects of long periods of burial is baked clay. At almost every single place where humans have lived, from the Neolithic age on, remains of their pottery can be discovered. Pottery is enormously important to archaeologist, no only because of its omnipresence, but also because it permits them to answer another question with near certain exactitude: when did these people live? Pottery answers this question because people of different time periods and different cultures made different kinds of cups, pots, jars and so forth. Pottery varies according to the shape of the vessel, the type of clay, the nature of the decoration outside or inside the pot, and the technique employed for shaping and firing. [Source: David Silverman, Reed College, Classics 373 ~ History 393 Class ^*^]

 “Imagine that an archaeologist from far in the future was digging a late 20th century site, and that clothing served for him the function that pottery does for archaeologists of ancient sites. He finds two layers, each representing the occupancy of a space by a different group of people at a different time. In settlement "A" everyone wore bell-bottom jeans; in settlement "B" (which is closer to the surface than settlement "A") everyone wore big baggy shorts which reached to mid-calf. The archaeologist would then refer to an already established chronology based upon the preference for pants styles at other late 20th century American sites, and he would then be able to date settlements "A" and "B" within a margin of error of around five to ten years. And in fact a margin of error of ten to fifteen years is typical for dates based solely or primarily upon pottery evidence."*^

 “Pottery dating is not perfect. First of all, one might think when finding out for the first time about how important pottery is for archaeological dating, it is so low-tech. What about the analysis of the breakdown of radioactive isotopes, carbon 14 dating? Actually, carbon 14 dating tends not to be very helpful to archaeologists (more so to geologists and the like). Carbon-14 dating only works on items which contain carbon, such as wood or coal. And in some cases C-14 dating can tell you only when an object's raw material first came into existence, as opposed to what you really want to know, which is when the material was shaped into its current form." ^*^