Variability and Occupational History in 17th Century Plaza Contexts at LA 162

Sandra L. Morrison¹, Melissa M. Cole^2, and Mark T. Lycett¹
(¹University of Chicago, ²Vassar College)

 Prior to 1996,  excavations at LA 162 concentrated on architectural space.  Plaza surfaces and exterior areas recieved almost no attention. Plaza space, in particular, was an important social and ceremonial space as well as an arena of mundane, everyday activity.  Our research examines these under-represented areas through a dual program of stratigraphic tests and horizontal exposures.  Seddon and Johansen, this session, discuss some of these horizontal exposures. Here we consider the depositional history of the test excavations.   The goals of these excavations are to investigate the construction, use and occupational history of the seventeenth-century plaza, and how these indices vary across space.

LA 162, Test Units Excavated in the Historic Plaza, 1996-2001

In order to investigate the variability of extramural deposits and the occupational history of the historic plaza, one by one meter test units were selected for excavation using a stratified random sampling strategy.  Since 1996, five test units have been excavated    (see Figure 1).  Where features or significant deposits were exposed, the test units were expanded into either two by two meter units or five by five meter block excavations.  Comparison of the deposits and stratigraphy of the test units has provided a picture of occupational history  in plaza construction, use, and maintenance during the colonial occupation at Paa-ko.
 

 Village sites with extensive extramural excavations exhibit evidence of intensive domestic and public use of plazas in the form of abundant and well preserved feature and artifact distributions.  In five seasons of excavation we have documented a wide array of features on as many as seven superimposed  plaza surfaces.

 The historic plaza is surrounded on four sides by partially excavated roomblocks and cross cut by several prominent masonry enclosures. Our excavations suggest that some of these enclosures were part of one or more corral systems while others appear to be simple divisions of plaza space or foundations for ephemeral structures.
 

 Kiva I (Nelson's Kiva B) and Kiva II (Nelson's Kiva A) were tested by Nelson and fully excavated during the 1930s.  A third kiva depression (Mapping Feature 20) is located in the southwest quarter of the plaza.  This depression is overlain by the foundations of a colonial period structure.  Our investigation of  these features is discussed by Lycett, and Johansen.

                                                                                                Ely, A.G.
                                                                                                1936 PAAKO, 5/5/36 to 9/8/36. Unpublished field notes on file at the Laboratory of Anthropology,
                                                                                                 Museum of New Mexico, Santa Fe.
 

 Excavtions in this area have been extensive.  Nels Nelson excavated eleven rooms is three transverse sections of Roomblock XI, and  an additional 37 rooms in the west (IX), north (X), and east (XII and XIIa) roomblocks of this plaza group.  Eighty eight rooms in Roomblock XI and the southwest corner of Roomblock IX, as well as portions of the plaza immediately adjacent to these roomblocks were excavated between 1935 and 1937.  In regard to these plaza excavations, field notes from September 7, 1936 note, "This area is comparatively barren. Tho [sic] several layers of ash and charcoal are to be noted" (Ely 1936).

 The results of our test excavations, however, indicate a significantly more complex depositional sequence than is anticipated by these comments.  Strata of ash, charcoal, and midden fill are interdigitated with repeated episodes of plaza construction. All of these deposits are associated with late glaze ceramics and European domestic fauna, indicating 17th  century occupation. These deposits document a history of regular maintenance and resurfacing of plaza space throughout the occupational sequence of LA 162 and are particularly useful in addressing colonial transformations of spatial organization and production.
 
 

 The south-central plaza: 41E/-150N

The depositional sequence within the historic plaza was established on the basis of two stratigraphic test units excavated in 1996.  Five to six strata were consistently identified in the profiles of these units.  The upper most stratum consisted of greyish brown, soft, loose, moist, organic rich sediment with abundant angular gravel, scattered cobbles, and moderate to high artifact density.  Artifact density declined with depth, while gravel, caliche, and charcoal abundance increased.  These sediments are highly disturbed by rodent burrowing and include mixed deposits of  artifacts from different periods.  Over much of the area, this matrix directly overlies the uppermost plaza surface.  This constructed surface consists of a distinct, undulating compact red-brown clayey layer with pebble and caliche inclusions, charcoal flecking. It consists of multiple, superimposed plaza surfaces with associated features.

                                                                                                                                         41E/-150N
 
 
 

 Subsequent excavations in Blocks A and C follow the patterns first recorded in 1996, except in the area of the plaza converted to domestic animal pens. The interior space defined by the corrals is associated with surface 1, an irregular and undulating stratum composed primarily of animal dung. This  matrix consists of compact, yellowish brown silt loam with platy, fibrous organic inclusions.   Included within this matrix are moderate to high densities of ceramics, chipped stone, and animal bones.  The ceramic assemblage analyzed to date is dominated by late glaze bichromes and polychromes and smoothed, striated plainwares.  The faunal assemblage includes small, medium, and large mammals including domestic horse and goat.   All of these deposits are consistent with seventeenth century occupation.

Although two distinct, constructed surfaces were identified in these excavations, the history of maintenance and resurfacing of the plaza is certainly more complex and continuous.  Surface 2 is the last occupied plaza surface identified in these excavations.  It was first encountered at a depth varying from 1.56 to 1.68 meters below datum. Forty three features were identified in association with this surface including  several semi-circular shallow, ash filled depressions, as well as a hearth, small pits, post holes, a large trash filled pit, and two burned jacal structures. Most features on this surface are relatively irregular concentrations of ash, charcoal, and cobbles.  Surface 3 was the earliest plaza surface exposed.  This surface was encountered at a depth of between 1.56 and 1.76 meters below datum. A total of 21 features were identified on this surface, including a two partial structure foundations, a hearth, and several shallow pits.  Both surfaces appear in profile as Stratum 2.

 Stratum 5, an underlying plaza surface,  lies directly beneath stratum 2 throughout the unit, but is cut by features, rodent holes and an ash lens so that the boundary between these layers is discontinuous. It is a thicker, more irregular red-brown clay loam layer with abundant charcoal and gravel inclusions.  Beneath this surface are culturally sterile strata of variegated pink, red, and white sandy clay and friable, variegated sandstone bedrock.

The central plaza: 48E/-137N

 48E/-137N is located in the central part of the plaza, approximately four meters southwest of Kiva I.  This unit is dominated by a single large pit feature excavated into the first plaza surface.  Six strata were identified in profile, following the same general sequence identified, above.  In this area of the plaza, however, the first constructed plaza surface sits atop a loose silt loam matrix rather than an earlier surface.
 

The Northern Plaza:  37E/-109N and Plaza Block B 

Block B is located within the masonry enclosure appended to the  northern roomblock of the Historic Plaza Group.  There is no evidence of animal penning within this enclosure.  The overlying  matrix consisted of light brown, soft loose fine sandy loam with moderate densities of artifacts and high densities of charcoal.  Charred material included wood charcoal, seeds from a variety of taxa, bean fragments (Phaseolus vulgaris), corn cobs and cupules (Zea mays), and cucurbit stems (Cucurbita spp.). Both charcoal and artifact densities increased with depth, reaching their highest levels at the interface with plaza surface B1.

 In the northern part of the plaza, there is a single constructed plaza surface.  Follwing the gradient of the contemporary ground surface, the depth of deposits in this area is quite shallow. Plaza suface B1 consists of a homogenous, compact reddish-brown silty clay loam with abundant caliche and charcoal inclusions. Several features occur in association with this surface, the largest of which is more than 1.5 meters in diameter.  The gently undulating surface was encountered at a depth ranging from 66 to 81 centimeters below datum.  Consistent with the present day topography, it slopes from northwest to southeast.  This surface lies directly on culturally sterile deposits.
 
 

  The Stratigraphic Sequence

 Previous test excavations in the historic plaza have documented multiple construction episodes and shifts in spatial organization during the colonial period. Nevertheless, the results from this test unit suggest a significantly more complex depositional history than was anticipated.  Strata of ash, charcoal, and midden fill are capped or underlain by seven plaza surfaces. Beginning from the base of cultural deposits, three plaza surfaces were constructed directly atop one another.  Each of these surfaces is consistent in construction, thickness and depth with plaza surfaces documented in Blocks A and C.  Above these are layers of ash, charcoal, midden fill, and structural debris interdigitated with  episodes of plaza construction.   No corral deposits such as those documented in 1997 and 1998 were encountered in this test unit.  However, stratum 4 does contain inclusions visually consistent with burned animal dung.  The chemical composition of these samples have not yet  been analyzed.  All of these deposits are associated with late glaze ceramics and European domestic fauna, indicating seventeenth century occupation. These deposits document a history of regular maintenance and resurfacing of plaza space during this period. They further document repeated burning and redeposition of burned material.  Some of this burning may have been associated with the maintenance of corral areas and the removal of dung, or may have simply used dung as fuel.  In either case, use and continued maintenance of this plaza surface clearly continued to very late in the occupational sequence of LA 162.
 

 Plaza surface 1consists of a distinct, undulating compact red-brown silt loam layer with gravel inclusions and abundant charcoal flecking. This stratum is five to twelve centimeters  thick and  exhibits a gentle slope to the north and west.  It was encountered at depths ranging from  1.13 to 1.205  meters below datum.  No features occurred in association with this surface.     No evidence of animal penning was encountered.

Plaza surface 2 occurs at a depth of 1.215 to 1.285 meters below datum.  This surface is no more than two to three centimeters thick.  It is overlain by a thin lense of yellowish-grey ashy silt loam that separates it from plaza surface 1.  The surface itself is comprised of red-brown compact silt loam with charcoal and gravel inclusions. Two features were recorded in association with this surface, including 21E/-145N/F1, a large, highly burned pit feature.

A thick layer of ash, with possible inclusions of decomposed dung was deposited atop plaza surface 3.  This layer may indicate that some animal penning was occurring in this area of the plaza, yet it is not as dense a dung deposit as was seen in Blocks A/C, which may suggest that there was either more maintenance occurring there, or that this area was not a formal corral.
 

                 Surface 2                                                                                                             Surface 4

 A variegated layer of ash, charcoal, adobe, and burned matrix was laid down over plaza surface 4, and on top of this,  plaza surface 3 was constructed. . It was encountered at depths ranging from 1.335 to 1.455 meters below datum.  The stratum ranges in thickness from two to thirteen centimeters.  It  dips and becomes thinner  to the north and east.

 A variegated layer of ash, charcoal, adobe, and burned matrix was laid down over plaza surface 5, and on top of this , plaza surface 4 was constructed. Surface 4, encountered at depths ranging from 1.395 to 1.535 meters below datum,   is never more than seven centimeters thick, and frequently less than two centimeters thick.  High densities of artifacts and structural debris occur in association with this surface.  Two features were recorded on this surface, including a small wattle and daub structure (22E/-146N/F2) and a shallow pit feature.

Plaza surface 5 is an undulating layer of compact grey-brown to red-brown silt loam with abundant ash, charcoal and gravel inclusions .  It was encountered at depths ranging from 1.605 meters below datum in the southwest to 1.765 meters below datum in the southeast.  The surface is 0.8 to 1.2 meters thick. It exhibits a gentle gradient from west to east. small wattle-and-daub structure (22E/-145N/F2) is associated with this surface.

 Plaza surface 6 was constructed on top of surface 7 out of similar matrix to that of plaza surface 7, with no fill layer between the two. The surface consists of burned and highly compacted, red-brown  silt loam with charcoal, ash, and gravel inclusions. It occurs at a depth of 1.745 to 1.860 meters below datum.  Two pits are associated with this plaza occupation.

 Plaza surface 7 was constructed on top of sterile soil out of pre-colonial plaza and/or roomblock deposits mixed with sterile material. It is distinct in color, texture, and consistence from the overlying deposits.  It is the earliest identified plaza surface in the historic plaza.  It occurs at depths ranging from 1.825 and 1.925 meters below datum and is up to 25 centimeter thick.  Reversing the dominant gradient of previous plaza surfaces documented at LA 162, surface 7 slopes from east to west.  Three pits were associated with this plaza occupation.

                             Surface 6                                                                                                                       Surface 7
 
 

 These excavation have helped to clarify the  relationship between these seven plaza surfaces and the surfaces documented in other excavations.  The stratigraphy, construction details, and depth of plaza surfaces documented in test unit 41E/-150N  are similar to those associated with surfaces five through seven in the present test unit.  That is, a sequence of relatively thick, constructed plaza surfaces is lain directly over  a culturally sterile stratum of variegated clays.  Surfaces A/C 2 and A/C 3, then, are most likely to correlate with surfaces 5 and 6 in the present test excavation.  While these surfaces remained in use on the southeastern quarter of the plaza, there appear to have been ongoing episodes of new deposition and construction in the southwestern quarter of the plaza.  These upper surfaces (1-4) are thin and separated by deposits of ash, charcoal and midden fill.  These sequences have not been documented elsewhere on the plaza.  Their presence suggests intensive activity in this area continuing throughout the latest residential occupation of the site.

 In contrast, in the northern and central areas of the plaza there is a single stratum of  plaza construction, reflecting a less complex and varied depositional history. 

  The occupational and depositional history of this test unit should be considered in terms of three sets of architectural features at the site.  First, our work with notes and collections suggests that the western third of Roomblock XI was probably no longer occupied during the final stages of residential use of the site.  Thus, much of the depositional history documented in 21E/-146N probably took place after rooms immediately to the south of this unit had been abandoned.  In general, occupation appears to have been shifting toward the southeastern quarter of the plaza during this period.  These shifts are reflected in the complexity of construction and deposition in the southern plaza  as well as in changes in domestic architecture.

 Second, Mapping Feature 167, a probable corral wall, encloses this area of the plaza to the north.  Nevertheless, clear evidence of animal penning is absent in this unit.  It is  possible that dung deposits were never as thick or continuous as elsewhere within the corral space or that differential maintenance accounts for the thick accumulations of animal dung to the east. It is also possible that corral space was once subdivided by a structure that is not visible on the surface.

  The corral and enclosure systems that dominate the southern third of the plaza may have been built in  association with the large , public structure discussed by Johansen, this session.  The plan and dimensions of this structure are similar to those from some seventeenth century churches documented elsewhere in New Mexico, and it may be the remnants of small chapel associated with the visita of San Pedro.  This structure was part of an important and as of yet poorly understood reorganization of public space following colonial missionization.  During this period, LA 162 was incorporated into Spanish economic, legal, administrative, and social networks.  New technologies, domesticates, and foreign biota were introduced and at least partially incorporated into existing land use and economic systems.  Historic and archaeological data are consistent with multiple discontinuous occupations, contraction of residential space, resurfacing and reconfiguration of extramural space, and construction of new and sometimes novel facilities at the site.  The complex history of plaza  construction and use  during this period is integrally tied to these  these  changes in the conditions of daily life.

The south-eastern plaza: Implications for Post-Residential History
 

59E/-146N is situated within a U-shaped masonry enclosure abutting Roomblock XI.  The interim results of these excavations suggest that while the depositional and occupational sequences identified in previous seasons are correct  in outline, there is variation across the plaza.  Despite limited exposure and incomplete excavation, the excavation of this unit clearly demonstrates the importance of that variation. The earliest plaza surface documented in this exposure is overlain by a series  of compact, gravel rich sediments that are consistent with stable land surfaces rather than prepared plaza surfaces. A masonry corral enclosure was constructed directly atop the latest of these surfaces.  The deposition of these matrices prior to the construction of a corral suggests that significant time elapsed between the abandonment of the plaza surface and the penning of animals on this area of the plaza.  Animal dung and butchered animal elements were deposed within the enclosure following its construction.  The wall collapsed directly on this surface with little or no intervening deposition.

This sequence differs from that documented in Blocks A and C.   In Blocks A and C, similar masonry corral walls were constructed over existing post alignments that defined the original animal enclosure.  No evidence of a prior corral was found in 59E/-146N. These differences in deposition and construction suggest that the southeastern quarter of the plaza was converted to corral space later than the southwestern quarter and almost certainly after the end of the residential occupation  of Roomblock XI.  This corral enclosure may be contemporaneous with other masonry corrals on the south side of the historic plaza, however, it does not appear to have been constructed over an existing corral system.  Rather it was appended to an that system following the residentail occupation of LA 162.

 The post-residential occupation of LA 162 is not unusual.  Villages abandoned as residential places in the sixteenth and seventeenth centuries took on new roles as logistical elements in an emerging mixed pastoral and agricultural land use system.  Residential abandonment does not necessarily signal a loss of place, but rather  a reconfiguration of its role and historical associations. Settlements like Paa-ko became campsites, corrals, raw material sources, and landmarks in the evolving  cultural geographies of the colonial southwest.
 
 

    Plazas and other mundane interstitial spaces are important landscape elements in these larger cultural geographies.  They are more than the substrate of architectural form and the backdrop of everyday activities.  The history of open space is key to understanding how places are made and reconfigured through time.  At LA 162, this history suggests an intensive and spatially differentiated use and restructuring of extramural space attendant upon colonial incorporation and the complex social and economic transformations of the 17th century.