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Excavation Methodology

            Our test pit locations were determined in conference prior to the field season and refined at the site during the field season. Prior to excavation, we prepared a computer map for the crew chief showing our intended pit location and nearby survey reference points and structures.  Our excavation crew chief then located the test pit as closely as possible to the position given on the work map, while still avoiding trees and other formidable obstacles. When the pit had been located in the field and staked, the crew chief then remeasured its location from the nearby survey control points and structures. These final locations are the ones reported here.

            Each pit was staked at its four corners using a measuring tape and compass.  We tied twine to the four corner stakes, or to pairs of stakes near each corner stake, and levelled it with a line level to establish a datum level for the pit. The datum varied from 0 to 20 cm above ground.

            The crew cleared the surface of all vegetation and collected the sherds found during this process. These sherds are separately recorded under test pit excavations as level zero or level one.  After clearing the surface we excavated the first layer of soil in such a way as to make the bottom of the test pit flat even if the surface terrain was uneven.  From that point we excavated in 10‑cm levels until reaching obvious changes in soil or upon encountering artificial features, such as a floor within a platform. The excavations, therefore, yielded both natural and artificial levels. With the exception of test pit #26 on the slope of the edge of the karstic shelf, all test pits were excavated with each level relatively flat.

            All earthen material was removed from the pit in buckets and sifted through a 4-mm wire mesh. The advantage of a mesh this fine was that it caught small but identifiable sherds, obsidian blades, and fish bones. Screening was more time consuming, however, than it would have been with a larger mesh. We also recovered a high fraction of small unidentifiable sherds as a direct result of using small-mesh screen. These unidentifiable fragments are included in the counts and weights reported.

            Large stones, which we encountered as platform fill or in the collapse zone adjacent to a structure, were removed from the test pits individually. Very large stones were broken with a maul within the pit and, as necessary, removed with a pulley hoist hung from a pole tripod. Access to deep pits was via ladders which were hand-made by our workers as necessary.

            We excavated the earth with small hand picks and trowels and controlled our excavation to 10-cm levels, where possible. This was easy to do in middens with few stones, but extraordinarily difficult in platform fill consisting of large stones. In some instances, levels containing very large fill stones were over a meter in depth.

            Material recovered from each level by the excavator(s) and by the person(s) screening the earth was bagged separately for each level. Small items, such as obsidian blades and fragments of carbon, were individually wrapped in aluminum foil. Excavation notes were recorded by the supervisor of the excavation and lot bags marked with their pit number, level number, date, and excavator. Lot numbers were assigned sequentially at the end of each day for the lots excavated that day. In some cases, a highly productive level produced more than one lot bag of material.

            The details of the Muyil excavations are reported in Appendix 1 (a lot register in numeric order) and in Appendix 2 (where the details of the material recovered from each test pit level are recorded).

            I report the following in Appendix 2: for surface collections, the provenience (location on the site in X-Y coordinates), and brief notes. For test pit excavations I report the pit number, the dates opened and closed, the nearby structure or structures that we sampled with the test pit, the location (the X-Y coordinates on the site map of the southwest corner of the test pit), and the size of the pit in meters north and meters east. Test pits excavated into platform fill frequently tapered inward toward the bottom to avoid dislodging large stones.

            Most test pits were oriented so that their walls aligned to cardinal compass points.  For these test pits we recorded the bearing of a north-south wall of the pit as N (north). For those few pits not aligned to the compass points we report the bearing of the pit as, for example,  N 20 E, which means that the north-south walls of the pit actually have a compass bearing which is 20 degrees east of north.  We have further recorded for each test pit our label as to the type of pit, such as "elite residential platform." We recorded for each pit whether or not the material was screened, and if it was screened, the size mesh, usually 4 mm. We recorded the maximum depth the pit reached below the datum line, which was not necessarily even with the pit surface. We recorded under the label "excavator" the last name of the crew chief responsible for the test pit. Each test pit has recorded for it a synopsis of the excavator's field notes and separate analytical notes prepared after the recovered material was analyzed.

            For each level of each test pit, we recorded the level number, which on occasion is supplemented by a letter suffix for subdivided levels, the depth of the top of the excavation level and the bottom of the excavation level and the (computed, not measured) number of cubic meters of material excavated. An individual level of a test pit may have both field notes and later notes from the analysis. Within each level there may be one or more lot numbers of material. Within each lot the material recovered has been listed and we have shown count, weight, primary form, secondary form, analysis code, description, whether or not a drawing was made, and notes. (If a field or laboratory drawing was made, it was not necessarily included in Appendix 4 on ceramics in some cases it was too small or otherwise unsuitable.) For ceramics, the count represents the number of potsherds after gluing together any matching fragments. These matching pieces were usually detected by noticing a freshly-broken edge evidence that the sherd had been broken during our excavation. Weight given is the weight in grams. Weight was determined as described in the chapter on ceramics. Primary form indicates the vessel part from which the sherd came, such as rim, neck, base, or body. Secondary form is used to describe sherds for which there was an obvious reuse, such as a net sinker made on a rim sherd or a pendant made from a piece of polychrome. Under description, I show the ceramic group, type and variety or nearest best designation if the ceramic could not be identified to the variety level. The word "yes" appears under the heading "Drawing" for those sherds for which a drawing was made in the field notes. Many of these drawings have been used to prepare illustrations of vessel forms and may be found in Appendix 4 with the type-variety ceramic descriptions.

            For the 53 test pits where sufficient material was available, there is a battleship diagram for the ceramics of that test pit. It shows the relative proportions by count of the individual ceramic types in each level and illustrates how they change with depth (time). In addition, there is a drawing of the test pit profile, plus individual plan views where the complexity of the excavation warranted reporting them.

            With this excavation strategy, we have obtained evidence, discussed below, that documents part of the history of the site, the period of use of many structures, the construction era and period of use of the sacbe, and the extent of connections with other points in the Maya area.


Copyright 2000-2005 Walter R. T. Witschey   Page last updated Wednesday, April 02, 2008