Out of the Peat: Preliminary Geophysical Prospection and Evaluation of the Mid-Holocene Stationary Wooden Fishing Structures in Haapajärvi,Finland

The huge scientific and interpretive value of wetland archaeological sites has been well demonstrated in several studies. The management of the archaeological resource of wetland landscapes is problematic, however, and there is an urgent need for noninvasive techniques to detect waterlogged organic archaeological remains. Stationary wooden fishing structures associated with fishing sites constitute an important wetland archaeological resource in northern Europe. In Finland, similar wooden constructions have been used for fishing from prehistory to the early modern era. The discovery of sites has been accidental, because the waterlogged organic remains have been considered invisible to conventional geoprospection techniques. Because of this, a small project was launched at Lamminoja, northwest Finland, in order to investigate whether it would be possible to improve our chances to detect fishery sites in demanding wetland habitats. New information was obtained through geophysical prospection, trial excavations, and accelerator mass spectrometry (AMS) dating. Geophysical testing was hampered by several factors, including complex sediments affected by modern drainage. New information was obtained, however, on the composition, age, and spatial distribution of the wooden fishing structures preserved in peat over 5000 years.     

A Spanish Man‐o‐War in New Zealand? The 1864 wreck of Grafton and its lessons for pre‐Cook shipwreck claims

This paper considers the 1864 wreck of Grafton in the Auckland Islands, and its implications for wreck analysis and pre‐Cook exploration claims. The captain of Grafton, Thomas Musgrave, stated that the schooner was built from the wreck of a Spanish man‐o‐war, and archaeological analysis of the wreck found that the timbers are a tropical South American species, and had possibly been reused. The implications of this are clear; it is possible that timbers that originated in pre‐Cook (1769) ships lie in New Zealand, but without a full understanding of the historical and archaeological context of any such timbers, including their reuse in later ships, it is not possible to claim proof of pre‐Cook European exploration of New Zealand.     

The in situ preservation of archaeological remains: using lysimeters to assess the impacts of saturation and seasonality

Recent research has studied the effects of seasonal variability on waterlogged burial environments. In a new approach to the study of archaeological contexts, the use of controlled laboratory conditions via lysimeters has enabled new insights into the nature of short term fluctuations in saturation, and the impact that these can have on burial contexts. In addition, the protocols used have facilitated interesting insights into burial environments and the way in which fluctuations in saturation and seasonality can impact on the contained organic components within them.     

内蒙古赤峰市大山前第一地点夏家店下层文化的植被和生态气候

内蒙古赤峰市大山前遗址属于中国北方青铜时代早期文化遗存 ,出土了大量夏家店下层文化遗物 ,其年代为 2 0 0 0BC～ 15 0 0BC。本文对大山前第一地点 1996年发掘区中部的探方T4 0 6内F8H1灰坑出土的木炭碎块进行了种属鉴定 ,并对出土的不同树种的木炭碎块进行分类和称量 ,得知当时的地带性植被为油松林和蒙古栎林 ,生态气候为温湿类型 ,同时也存在着气候暖干波动现象 ;柳属的发现说明遗址附近有河流存在 ;根据蒙古栎的起源和生态特性推测这一时期可能有人类的砍伐活动 ;H1出土的油松木炭可能绝大多数属于薪炭遗存     

First Trials to Set Up a Microwave Reflectometric Tool for the Survey of Historic Timber Structures

Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage.

This article presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner.

The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna which transmits the continuous-wave (CW) microwave signal and receives the signal reflected by the material under investigation.

Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening.     

海洋出水木质文物保护中的硫铁化合物问题

海洋出水的木质文物中通常会沉积硫铁化合物。打捞出水后,硫铁化合物遇到空气和水分后会发生氧化,生成硫酸以及各种硫酸盐,并引起有机质的降解。近年来,硫铁化合物对海洋出水木质文物的危害已引起广泛关注。为此,本工作阐述了硫铁化合物相关问题的研究现状,就硫铁化合物的产生原因、危害以及目前控制方法的研究进展进行了总结,同时评述了针对硫铁化合物的处理方法。     

一件淮北市东汉“木侠纻”耳杯的测试分析

考古出土的漆器中,除木胎之外,有自铭“革园”的皮革与麻布为胎的漆器,有自称为“布”“绪”“纻”的麻布胎漆器,有自铭“布缯”的麻布和缯帛(一种丝织物)为胎的漆器,以及麻布夹贴于木胎之上的“木侠纻”漆器。作为夹纻胎漆器其中的一种类型,“木侠纻”漆器与“布胎”漆器在制作工艺上是否不同,二者之间是否存在技术演变关系的问题值得深入探讨。 本工作以2011年10月淮北市出土的一件东汉时期的耳杯为例,采用超景深视频显微镜、X射线衍射仪(XRD)、傅里叶红外光谱仪(FTIR)、扫描电子显微镜与能谱仪(SEM-EDS)等测试手段进行研究,深入了解汉代“木侠纻”漆器的工艺特点。显微结构观察发现在器物木胎与外层漆灰之间有着清晰的织物平纹组织结构,织物层的厚度仅占整体厚度的11.4%,远低于同尺寸“布胎”耳杯织物层所占的比例(后者一般在50%以上)。成分测试分析结果显示,髹漆材料为传统的中国大漆,红色漆膜呈色颜料为朱砂,织物材质可能为苎麻纤维,漆灰成分为SiO₂、NaAlSi₃O₈和Ca₈H₂(PO₄)₆H₂O等常见物质。上述研究结果说明,比较汉代“木侠纻”漆器工艺与“布胎”漆器,在髹漆材料、呈色颜料以及漆灰中矿物质成分等方面并无区别,仅在织物层的厚度所占胎体尺寸比例等方面有着明显差异。同时,本研究中发现“仅在木胎一侧贴附麻布”的做法与文献记载的“两麻布夹贴于木胎之上的木侠纻”工艺并不完全一致。 文章首次采用科技手段从制作材料、髹漆工艺等方面揭示了汉代“木侠纻”制作技术。事实上,从厚木胎斫制到薄木卷制成型,再到以布为胎,胎骨的变化见证了古代漆器水平的进化历程。从考古出土的漆卮、樽可以发现,薄木卷制而成的器型在两端的连接处仅依靠生漆或其他材料,其本身的结构并不牢固。古代漆工们为了防止木胎开裂,在接口处的木胎之上粘贴织物。这种借助于植物纤维的拉力增强木胎牢固性的技术即为“木侠纻”。当然,“木侠纻”工艺是否直接催生了“布胎”漆器还有待进一步讨论,但至少从传统手工业技术发展的规律可以进一步窥探两种工艺之间的借鉴或启示。时至今日,这种工艺在今天的家具、屏风制作中依然广泛使用。     

Near infrared spectroscopy as a tool for archaeological wood characterization

Archaeological wood, as most of natural materials, is slowly decomposing on the archaeological site due to various biological factors. Rapid and accurate estimation of the degradation level is extremely important for optimal restoration and conservation. The goal of this research was to verify the effectiveness of Fourier transform near infrared (FT-NIR) spectroscopy for archaeometry. The important advantage of the NIR spectroscopy is its accuracy, simplicity and ability to perform very high number of tests without needs of any destruction to the workpiece. Five oak pieces of the archaeological wood collected from waterlogged sites in Poland have been used. Cellulose and lignin contents, as well as crystallinity and the degree of polymerization were measured with standard reference methods and compared to the contemporary wood. The near infrared spectra represent all the physical/chemical changes of the wood due to waterlogging. This technique was successfully validated in rapid estimation of the cellulose and lignin contents. The method explored in this research might be a novel tool assisting experts in evaluation of the degradation state of archaeological and historical wooden materials.