Phosphate Analysis of Anthropic Soils

Abstract

The use of phosphate analysis in archaeology is possible because past human occupation and activities increased the amount of soil phosphorus in the areas occupied. The accumulated phosphorus in archaeological deposits tends to remain constant through time and is measurable through soil sampling and chemical analysis, thereby providing archaeology with a valuable tool, applicable to a wide variety of research situations. Phosphate analysis is especially useful in surveying large areas to locate and delimit sites.     

Relevance of soil biology and fertility research to archaeological preservation by reburial

Abstract

This paper discusses how soil biological information can help to improve understanding of, and possibly inform decisions about, preservation of organic archaeological remains by reburial. A brief summary of the properties of the soil biological community is followed by an outline of results from recent biological investigations following the recovery of archaeologically relevant materials that had been buried for thirty-three years in one of the experimental earthworks in England UK. Examples from the soil biology and fertility literature are discussed to illustrate the effects of fluctuations in soil wetness and aeration, and of nitrogen availability on decomposition. Finally, the impact of soil handling and physical disruption on biological processes in soil are discussed, as they influence whether soil functions can be restored at a reburial site once the archaeological resources have been ‘protected’ beneath.     

Physical and Geochemical Characteristics of Soils from Angel Mounds State Historic Site,Indiana, including a Case Study of Sherds from Unit A

Abstract

Using physical and chemical characteristics of soil to evaluate archaeological artifacts and their preservation potential along with associated features is well established. The soil characteristics and geochemistry of the Angel Mounds site (12Vg1) indicate the soil geochemistry is very homogenous and composed of loams and silt loams with a range of pH values from 4.69 to 6.17, mean value of 5.40 ± 0.47. The slightly acidic nature of the soil favors the preservation of pollen and soil diatoms, with minor corrosion potential for the bone, shell, and sherd artifacts. A comparison of the geochemistry of the soils from Unit A and site-wide sampling to sherds from Unit A suggests that elevated phosphorus (P) in the sherds is either the result of the addition of a P-rich temper material or from the sourcing of nonlocal clay-rich sediment, and not from use-derived residue or from the soils themselves.     

A Qualitative Approach for Assessment of the Burial Environment by Interpreting Soil Characteristics; A Necessity for Archaeological Monitoring

Abstract

Modern-day archaeological monitoring is often hampered by lack of money, lack of time, inadequate measuring equipment, and lack of insight in the conservation potential of a site.

Although in modern archaeological excavations soil characteristics are noted (colour, texture, groundwater level, and sometimes mineralogy), these characteristics are mainly used for the interpretation of a site. However, by looking to these characteristics from a conservational view eventually combined with the conservation status of the archaeological objects, much can be learned about the burial environment. This is essential for optimizing archaeological monitoring.

Degradation processes result from the change of reactive phases in the soil or the site. Reactive phases are soil components such as organic matter, sulfides, iron(hydr)oxides and carbonates (chalk, shells), and, if present, components in the ground or interstitial water such as hydrogen ions and sulphate. The presence of these phases can easily be established by the archaeologist or soil scientist in the field. We propose a simple field-based method for assessing degradation processes essential for in situ preservation and monitoring.     

Quantification and Visualization of In Situ Degradation at the World Heritage Site Bryggen in Bergen,Norway

Abstract

Environmental monitoring at the World Heritage Site of Bryggen in Bergen, Norway, has shown damaging settling rates caused by degradation of underlying archaeological deposits. Measurements of piezometric head, oxygen, and soil moisture content, as well as chemical analyses of water and soil samples are key elements of the environmental monitoring.

Groundwater monitoring and geochemical analyses reveal a complex and dynamic flow through the natural and anthropogenic stratigraphy. The preservation conditions within the organic archaeological deposits are strongly correlated with oxygen and soil moisture content, that are controlled by the groundwater flow conditions at the site. To quantify decay rates, it is thus essential to understand the wider hydrogeological context of the site. This paper presents recent advancements in quantifying decay rates in the saturated zone at Bryggen. The paper also shows that 3D geo-archaeological modelling can contribute to preservation management by visually combining results of geological, archaeological, geochemical, and hydrological investigations. This opens up for improved multidisciplinary understanding of preservation potential, thereby contributing to an improved protection of archaeological deposits in situ.     

Publications New Archaeological Books and Journals

Abstract

An electrical resistivity survey and accompanying soil analyses were performed over an exposed but unexcavated prehistoric house in Peoria loess in westcentral Illinois. Positive resistivity anomalies occur along the trenches for the house walls and within the house and distinctive patterns in contoured resistivity data occur over the house.

Soil analyses show that quartz, kaolinite, montmorillonite, illite, and hematite are the main mineral constituents in the soil. Within the house basin, the soil is dark gray in color because of the presence of organic carbon. Prominent positive electrical resistivity anomalies occur where the dark soil is thickest.

Analyses of the resistivity and soil data enable the identification of several anthropogenic features within the house and suggest that electrical resistivity data would be helpful to archaeologists in doing both detailed and reconnaissance work. For example, the mean amplitude and fabric patterns in contoured resistivity are distinctive over the house relative to areas outside the house. This fact suggests that similar analyses of reconnaissance resistivity data might be helpful in exploration for large archaeologic activity areas such as whole villages or camps. Also, detailed analyses of the resistivity and soil data, in conjunction with information already available from other excavated structures at Orendorf village, suggest that the electrical resistivity technique can serve as a valuable, but ancillary, tool to help archaeologists focus their efforts and decide which of the many structures in a village should be excavated.     

A still worm from excavations at Carrick Castle,Argyll

Abstract

During 1993 excavations at Carrick Castle, Argyll, a rare item of distilling equipment was unearthed. Possibly dating to the 17th century, the copper alloy condenser or ‘worm’ is unique in design. Pollen analysis of an associated soil sample supports a use in the production of grain spirits. The technology of manufacture and historical context of the worm are examined in depth.     

Electromagnetics for Mapping Buried Earth Features

Abstract

Electromagnetic surveys are a fast method of locating and mapping some large earth features such as leveled mounds and refilled ditches. They can be a substitute for resistivity surveys and are particularly suitable where the surface soil is dry, hard, or rocky, or where the vegetation is moderately dense.

As in all geophysical techniques, it is necessary that the features to be located are sufficiently different from the surrounding terrain. Results from three sites will illustrate the capabilities of electromagnetic surveys.     

Numerical Modeling of a Church Nave Wall Subjected to Differential Settlements: Soil-Structure Interaction,Time-Dependence and Sensitivity Analysis

ABSTRACT

Historic masonry structures are particularly sensitive to differential soil settlements. These settlements may be caused by deformable soil, shallow or inadequate foundation, structural additions in the building and changes in the underground water table due to the large-scale land use change in urban areas.

This paper deals with the numerical modeling of a church nave wall subjected to differential settlement caused by a combination of the above factors. The building in question, the church of Saint Jacob in Leuven, has suffered extensive damage caused by centuries-long settlement. A numerical simulation campaign is carried out in order to reproduce and interpret the cracking damage observed in the building.

The numerical analyses are based on material and soil property determination, the monitoring of settlement in the church over an extended period of time and soil-structure interaction. A sensitivity study is carried out, focused on the effect of material parameters on the response in terms of settlement magnitude and crack width and extent. Soil consolidation over time is considered through an analytical approach. The numerical results are compared with the in-situ observed damage and with an analytical damage prediction model.     

Thousand years of vegetation history revealed by pollen in a sandy soil,central Netherlands

Abstract

Within the scope of an interdisciplinary research project to determine the genesis and age of small clusters of oak trees, three soil sections in and three outside oak clusters in an ancient woodland/heath on the Veluwe, central Netherlands, were sampled for palynological analysis. The sections within the clusters show an undisturbed development from the Medieval period onwards, the sections outside the clusters are missing ca. 15 cm because of sod cutting associated with plaggen soil formation. The rate of downward movement of pollen was established, using known dates from the near surroundings.     

The Earth's Soil Our Ultimate,Shrinking Limit to Growth

Abstract

The loss of productive soil in the world was first brought to the attention of the international community at the Environment Conference in Stockholm, 1972. Subsequent discussions have led to the suggestion that the slow rate of transfer to the developing world of the technology for its control was perhaps due to social and economic rather than to technological constraints. The background to this hypothesis and the attempt that is being made to validate it, are here described.     

Nitrates,water and salt: maintaining the fertility of agriculture

Abstract

The fertility of the soil depends on an ample supply of nitrogen compounds and on a variety of other nutrients and trace elements. The supply of nitrates by natural means has posed a limit to productivity since the inception of agriculture, and the avoidance of soil salination has been a necessity in many environments. Since the invention of an industrial process for fixing atmospheric nitrogen (the Haber process), there has been an ample supply of nitrates in the form of chemical fertilisers, capable of sustaining agriculture worldwide, and enabling it to feed the burgeoning human population. The growth in agricultural supply has been attributable, in the second half of the twentieth century, to the combined agency of hybrid crop species, chemical fertilisers and irrigation. Now, at the beginning of the twenty-first century, the problem of soil salination is limiting this growth and threatening to reverse it.     

Monitoring the burial environment of terrestrial wet archaeological sites in The Netherlands

Abstract

Monitoring the burial environment of archaeological sites is necessary to assess the success of their preservation in situ. Also, monitoring the state of preservation of actual archaeological remains together with that of their burial environment will further our understanding of the degradation processes acting on archaeological remains in situ. These remains consist not only of objects made from wood, metal, stone, etc., but also of pollen, soil features and even micromorphological features. Although, to date, the precise degradation mechanisms of archaeological remains in situ are not yet fully understood, general agreement exists on which parameters should be monitored in wet terrestrial environments. Also, it has been established that in situ measurements are preferable to laboratory analyses of soil (water) samples. In practice, it is difficult to find suitable monitoring equipment for in situ measurement as it must meet many requirements: an in situ measuring principle; stable for a period of at least several months; robust for use in the field; and equipped with a datalogger. A suitable principle exists for measuring the redox potential, however a simple, robust field instrument with datalogger is not yet available. Monitoring of the water table level, temperature and oxygen content is possible with recently developed, commercially available instruments. Monitoring of acidity is less complex as it does not vary as rapidly as, for example, the redox potential; however, the recommended method is still based on analysing soil samples, which is not acceptable in the long term at archaeological sites.     

GEZA‘

Abstract

Through a material and exegetical analysis of the texts in question (Isa 11, 1; 40, 24; Job 14, 8) the thesis demonstrates that from a horticulotural point of view, gz‘ displays the characteristics of a cutting (contextually perhaps a root sucker): gz‘ is a shoot taken from a tree (though its being cut off is not explicitly stated), planted in the soil where it takes root, it grows up, and in the religious imagery it is watered by the gardener who decides its fate.     

Monitoring of soil moisture in backfilled soil for conservation of an Ancestral Pueblo an great house in Chaco Canyon

Abstract

An automated monitoring station, with climate sensors and a three-dimensional array of soil moisture sensors, was installed to document moisture-content changes in backfilled soil covering an Ancestral Pueblo an ‘great house’ at Chaco Culture National Historic Park, New Mexico, USA. The objective was to evaluate the performance of a geomembrane installation in the soil. Prior to its installation of the geomembrane, we observed that precipitation in winter and spring penetrated only 60–90cm into the fill during the first year after backfilling. A significant amount of moisture evaporated from the surface during the summer months, consequently the driest region was at the surface. In the following twenty-four months we observed continued dissipation of the trapped moisture towards the surface. The installation of the geomembrane system during the second year maintained a stable and dry soil environment, indicating effective surface removal of precipitation and preventing moisture penetration deeper into the soil.     

Effects of Near-Fault Pulses on Nonlinear Soil-Structure Systems

ABSTRACT

This paper is focused on effects of near-fault pulse characteristics on seismic performance of soil-structure systems considering foundation uplifting and soil yielding. To this end, an extensive parametric study is conducted. Mid-to-high-rise buildings of different aspect ratios (SR) resting on shallow mat foundations are investigated. Different vertical load-bearing safety factors (F_S) of foundation as well as different soil types (i.e. soft to very dense) are considered in this study. Finite element method is used for numerical modeling. The underlying soil is simply modeled with a set of nonlinear springs and dashpots beneath the foundation. Mathematical near-fault pulse models of fling step and forward directivity are used as input ground motions. The results show that reduction in structural drift demands due to nonlinear soil-structure interaction (SSI) is more considerable in the case of short-period pulses compared to long-period ones. In more precise words, significant reduction occurs when pulse-to-fixed-base period ratio falls within 0.7–1.5 in the case of directivity pulses and 0.5–1.4 in the case of fling pulses. It is also demonstrated that the beneficial effects of nonlinear SSI reduce when the number of stories increases.     

A Predictive Map of Compression- Sensitivity of the Dutch Archaeological Soil Archive

Abstract

Weak soils like unconsolidated clay and peat may deform and compress considerably by loading, for example, by sand bodies for roads and railways. Archaeological sites within such easily compressible soil layers may therefore be heavily affected by different kinds of construction works. The vulnerability of archaeological sites to compression is largely dependent on soil properties like lithology, grain-size, and previous loading history. This may therefore differ considerably. Predicting the compression sensitivity is of great value for planners, since they can estimate in which areas in situ protection of archaeological sites may be feasible and where it would require (costly) technical measures or plan adaptations.

As part of the Cultural Heritage Agency’s research programme on construction and archaeology, we prepared predictive maps of the compression sensitivity of the subsurface sediments in the Netherlands for 1 m depth intervals from 0 to 20 m depth.

The maps were constructed using a full 3-D model of the subsurface of the Netherlands.

In combination with the Indicative Map of Archaeological Values (IKAW) that is already available, these maps can be used to better estimate the technical measures needed and costs involved for in situ protection of archaeological sites in the planning phase of construction projects.     

Investigating the Impact of Concrete Driven Piles on the Archaeological Record Using Soil Micromorphology: Three Case Studies from the Netherlands

Abstract

In this paper we present the results of field tests into the impact of driven concrete piles on three archaeological sites in the Netherlands. The field tests were done in two different types of archaeological sites. Two locations in the northern part of the Netherlands (Kenwerd and Groot Wetsinge) were artificial mounds or terps, where new buildings were going to be constructed using driven piles. The third location was Voorburg in the western part of the country, where the impact of pilings from the 1950s were studied. We analysed soil which was in direct contact with the piles, and soil at a distance from the pile surface.

The tests show remarkable results. Visible effects of piling in sand were downdrag of sediments along with the pile, disturbance of structure by local displacements, or liquefaction. In clay, some disturbance of structure, compression of pores, and damage to carbonized material was observed. Additionally, piles may promote the formation of pyrite in the directly adjacent peat. In a large number of samples taken from soil directly adjacent to a pile, no disturbance was observed. We did not observe any impact further than six to eight cm from the pile surface.

These results indicate that the impact of piling in fine sediments is smaller than is generally assumed. However, as the number of observations in the present study is relatively small, the results need to be corroborated by more field tests. In future, planners need to consider the direct effects piles have on the surrounding soil as well as the possibility of excavations.     

Research on Conservation State and Preservation Conditions in Unsaturated Archaeological Deposits in Oslo

Abstract

Archaeological, biological, and geochemical investigations of soil sample series from a section and five boreholes have been studied to evaluate the state of preservation at the time of investigation and the preservation conditions of urban archaeological deposits from medieval Oslo, Norway. Focus has been put on the most fragile deposits in the unsaturated and fluctuation zones. Even with limited investigations, it is possible to assess the archaeological conservation state and the preservation conditions. Further work should focus on interpreting measured results and on mitigation strategies.