Archaeological Chronology Research Articles

Cultural-Environmental Systems and the Archaeology of Climate Change and Social Complexity: Midwest and Southeast United States

The investigation of dynamic fully integrated cultural-environmental systems is one grand challenge facing archaeologists in this century. In the Midwest and Southeast United States, archaeologists recently increased their study of Mississippian social systems (ca. AD 1000–1600) in relationship to paleoclimate and paleoenvironmental data. Significant differences in chronological control between archaeological chronologies and paleoenvironmental records pose challenges to the study of cultural-environmental systems in this region and often result in equifinal results. Three major lines of paleoenvironmental records are reviewed: bald cypress tree-ring records, the Living Blended Drought Atlas (LBDA), and lake-bottom sediment cores. The strongest approaches include local and regional multiproxy environmental records from the same location as a well-investigated archaeological site(s) or region(s). In the rare case where the cores also encode a regional population history, it may be possible to develop stronger inferences that consider variation within and between communities and their vulnerability to climate change and environmental catastrophes.

The origin of the Protogeometric style in northern Greece and its relevance for the absolute chronology of the Early Iron Age

Classical archaeological chronologies are steeped in relative dating, but the application of absolute methods does not always support such clear-cut seriation. Here, the authors consider the significance of a Macedonian vase in reconciling the conventional and absolute chronologies of Early Iron Age Greece. Decorated with compass-drawn concentric circles and found in a Late Bronze Age context at ancient Eleon, Boeotia, the authors argue that this vessel establishes a chronological anchor and supports a twelfth-century BC emergence of the Protogeometric style in central Macedonia. A model for the indigenous development and dispersal of the Macedonian Protogeometric style is presented for future elaboration.

Study on Production Characteristics and Change in Production Location of Pottery Excavated from DongOe-dong Site in Goseong

As a result of scientific analysis of 26 pottery excavated from the DongOe-dong site in Goseong, pottery with various firing degrees was confirmed, ranging from low-firing pottery with mica minerals detected to high-firing pottery with high-temperature minerals such as cristobalite and mullite detected. In addition, low-firing pottery has an absorption rate of 9.7∼25.8% and generally shows high saturation value. On the other hand, high-firing pottery has low absorption rate and saturation value, so the physical characteristics of the pottery show a high correlation with the group classified by XRD analysis. Pottery with a low firing degree commonly contains fine-grained mineral particles and has a similar composition of trace elements such as Rb, Ba, and Sr. And they were most abundantly excavated from the No. 1-1 moat. However it was confirmed that there is a difference in the production area because compositions of the rare earth elements are distributed in two areas in the graph. High&intermediate-firing pottery samples are observed to have a vitrified base matrix and relatively less temper minerals. And their contents of Rb, Sr, and Ba are significantly different from low-firing pottery. In the composition of rare earth elements, they are all distributed in same area as one of the separated areas of low-firing pottery, so it is highly likely these pottery were produced in the same or nearby production region regardless of the firing degree. As a result of checking up the composition of rare earth elements according to the archaeological chronology of pottery, it is estimated that there was a change in the production region of the pottery introduced into the DongOe-dong site around 250 AD.

Building culturally meaningful chronologies: negotiating Indigenous and Western temporalities in Oceania

ABSTRACTThis paper examines some of the ways in which Indigenous and Western archaeological chronologies are being negotiated and entwined in Oceania. Indigenous pasts are often known through oral traditions, genealogies and ancestral landscapes; these are vital pasts populated by the ancestors. The archaeological past is often interpreted through taphonomy, stratigraphy and direct dating techniques. There are tensions and intersections between these perspectives, and research partnerships between archaeologists and Indigenous communities must negotiate how to build chronologies and narrate the past. Drawing on case studies from our research in Australia and Papua New Guinea, we discuss how these seemingly different ways of knowing the past can be brought into productive conversation and how these understandings are transforming today. We argue that incorporating diverse temporalities for ancestral places can generate richer historical narratives of value to communities and researchers.

Radiocarbon-Refined Archaeological Chronology and the History of Human Activity in the Southern Tarim Basin

Famous for Taklimakan, the world’s second largest sandy desert, the Tarim Basin in Xinjiang has long attracted researchers from various fields to investigate its paleoenvironment and antiquity. The southern part of this basin is an ideal region in which to investigate the interactions between humans and the environment due to its fragile habitat and prosperous ancient civilizations. However, the lack of direct radiocarbon dating data has caused the chronologies of some of the archaeological sites to be debatable, which hinders our ability to reconstruct historical patterns of human activity and further understand, in a coherent manner, their interaction with the environment. This study reports 25 new radiocarbon dates acquired from ten undated archaeological sites in the southern Taklimakan Desert in order to refine their chronologies. Based on this, a radiocarbon dataset was established to reveal the trajectory of human activity with the support of Bayesian chronological modeling. The results indicate a two-millennium continuous flourishing of the local society since the beginning of the first millennium BCE, as well as a peak of human activity during the Tang Dynasty (618–907 CE). The distinct trajectory of human activity in the southern Tarim Basin revealed by this study provides a solid foundation for further assessments of human–environment interaction in the Tarim Basin and along the Silk Road.

Placing radiocarbon dating at the center of collective archaeological practice

ABSTRACT Radiocarbon analysis is a common tool used to obtain the absolute ages of materials from archaeological contexts. This method underlies the basis of most archaeological chronologies across the globe, allowing us to better understand the temporality of past events. However, in the American Southeast, research by a small number of academic archaeologists who are interested in specific kinds of sites, time periods, and research questions drive radiocarbon dating efforts. This creates an uneven distribution of chronological and temporal frameworks that limits our interpretation of human behavior across time and space. In this report, we argue that if archaeologists want to control for time in the same way that we control for space in our interpretations of the archaeological record, radiocarbon dating must be practiced using a standardized methodology in all realms of archaeological practice – cultural resource management, academia, museums, and government agencies. To do this, archaeologists need to (1) better date individual sites and groups of related sites and (2) build an aggregate data set that more accurately reflects the reality of human behavior across time. We argue that cultural resource management, specifically, can play a key role in helping put radiocarbon analysis at the center of archaeological practice.

Echoes of the Past: Unveiling the Kharga Oasis’ Cultural Heritage and Climate Vulnerability through Millennia

The civilization and tangible cultural heritage of the Kharga Oasis has a historical precedence over that of the old Nile Valley civilization. Approximately 12,000 years ago, a significant prehistoric migration occurred from the Kharga Oasis to the Nile Valley. This event was motivated by climate change and the southward shift of the Inter-Tropical Convergence Zone (ITCZ), which caused a shift in Egypt’s savannah forests from abundant vegetation to an extremely dry desert. The present study investigates the progressive deterioration of the tangible cultural and civilized legacy of the Kharga Oasis over the course of several millennia, positing that this phenomenon can be attributed to the area’s vulnerability to paleoclimatic fluctuations. The evaluation of the Kharga Oasis’ susceptibility to climate change was predicated on the scrutiny of petroglyphs that were unearthed at different sites within the Oasis. This analysis was reinforced by paleoclimate information and radiocarbon dating (C14). The utilization of an interdisciplinary approach yielded significant insights into the dynamic climate patterns and their effects on the Kharga Oasis across temporal scales. The results illustrated a noteworthy alteration in climate, which caused the conversion of the Oasis terrain from being heavily wooded to becoming arid, mainly due to extended periods of drought. The present research postulates a novel and alternate hypothesis concerning the archaeological chronology of human habitation in the Kharga Oasis from ancient eras, predicated on the analysis of pictorial depictions on rock surfaces. The findings of this study made a noteworthy contribution to the current corpus of knowledge regarding the vulnerability of the ancient Egyptian society to the impacts of climate variability. Moreover, the petroglyphs’ depictions provided a distinctive viewpoint on the climatic fluctuations that occurred in the Sahara and North Africa throughout the Holocene epoch, as well as the fundamental causative factors.

Food globalization in southern Central Asia: archaeobotany at Bukhara between antiquity and the Middle Ages

The Silk Road is a modern name for a globalization phenomenon that marked an extensive network of communication and exchange in the ancient world; by the turn of the second millennium AD, commercial trade linked Asia and supported the development of a string of large urban centers across Central Asia. One of the main arteries of the medieval trade routes followed the middle and lower Zarafshan River and was connected by mercantile cities, such as Samarkand and Bukhara. Bukhara developed into a flourishing urban center between the fourth and sixth centuries AD, served as the capital of the Samanid court between AD 893 and 999, and remained prosperous into the Qarakhanid period (AD 999–1220), until the Mongol invasion in AD 1220. We present the first archaeobotanical study from this ancient center of education, craft production, artistic development, and commerce. Radiocarbon dates and an archaeological chronology that has been developed for the site show that our samples cover a range between the third and eleventh centuries AD. These samples from Bukhara represent the richest systematically collected archaeobotanical assemblage thus far recovered in Central Asia. The assemblage includes spices and both annual and perennial crops, which allowed Sogdians and Samanids to feed large cities in river oases surrounded by desert and arid steppe and supported a far-reaching commercial market in the first millennium AD.

The variable nature of the coastal 14C marine reservoir effect: A temporal perspective for Rio de Janeiro

The radiocarbon (14C) marine reservoir effect (MRE) is very sensitive to physical and chemical processes affecting the local carbon (C) cycle. In coastal zones, these tend to be numerous and complex, hindering the derivation of local marine reservoir offsets (ΔR) for the establishment of archaeological chronologies. Although discussions of how the magnitude of the MRE responds to factors such as the presence of coastal upwelling are common in the literature, little has been done to assess how the effect is influenced by a changing relative sea level. Here, we address the MRE temporal variation on the coast of Rio de Janeiro in the light of updated 14C calibration curves and considering the Holocene relative sea-level curve for the region. To achieve this, we employ Bayesian modelling to analyze published and new 14C ages from Brazilian archaeological sites and pre-bomb samples. In this study, we show evidence for a Late Holocene increase in the MRE, varying from −577 ± 56 14C yr at ca. 5500 cal BP to −29 ± 25 14C yr at present, associated with a decreased relative sea-level.

NEW HUMAN BONE RADIOCARBON DATES FROM THE ROMAN PERIOD–MIGRATION PERIOD LITHUANIAN CEMETERIES

ABSTRACTA set (n = 37) of new human bone radiocarbon accelerator mass spectrometry (14C AMS) dates from 11 Lithuanian Late Roman Period–Migration Period cemeteries is presented and discussed in the light of the established schemes of archaeological chronology. The focus of the paper is on the burials of the military and social elite, which indicate the emergence of new cultural traditions in E–S and W–Central Lithuania or the immigration that took place during this time. The 14C dates allow us to suggest corrections to the dominant chronological pattern of cultural development in the region.

CHALLENGES IN BUILDING ARCHAEOLOGICAL CHRONOLOGIES IN THE STANN CREEK DISTRICT

Key to archaeological research is our ability to recognize and define material-culture patterns and organize such patterns in time and space. Since 2014, the Stann Creek Regional Archaeology Project (SCRAP) has focused on understanding processes of settlement development and growth at the Ancestral Maya town of Alabama in East-Central Belize, constructed and occupied primarily during the transition period between the late facet of the Late Classic to Terminal Classic periods. While we may never know precisely who settled Alabama and why, we aim to answer questions about the where, when, and how of its development in our ongoing research. In following these lines of inquiry, we have had to grapple with several obstacles that have frustrated standard practices of building archaeological chronologies at the site. Such barriers include earthen-core architecture with minimal artifact refuse within platform cores. Additionally, local and regional soil conditions that result in a poorly preserved and highly fragmentary ceramic assemblage and no preservation of human or faunal remains to date. Finally, we face the difficulties of constraining the radiocarbon calibration curve during the primary period of Alabama’s settlement and growth. This paper details these problems and outlines our various approaches in their confrontation.

Settlement, environment, and climate change in SW Anatolia: Dynamics of regional variation and the end of Antiquity.

This paper develops a regional dataset of change at 381 settlements for Lycia-Pamphylia in southwest Anatolia (Turkey) from volume 8 of the Tabula Imperii Byzantini-a compilation of historical toponyms and archaeological evidence. This region is rich in archaeological remains and high-quality paleo-climatic and -environmental archives. Our archaeological synthesis enables direct comparison of these datasets to discuss current hypotheses of climate impacts on historical societies. A Roman Climatic Optimum, characterized by warmer and wetter conditions, facilitating Roman expansion in the 1st-2nd centuries CE cannot be supported here, as Early Byzantine settlement did not benefit from enhanced precipitation in the 4th-6th centuries CE as often supposed. However, widespread settlement decline in a period with challenging archaeological chronologies (c. 550-650 CE) was likely caused by a "perfect storm" of environmental, climatic, seismic, pathogenic and socio-economic factors, though a shift to drier conditions from c. 460 CE appears to have preceded other factors by at least a century.

Legacy radiocarbon dates and the archaeological chronology of the Western Pyrenees

The Western Pyrenees as a geographic region spanning portions of France and Spain is explored through the analysis of publicly available legacy radiocarbon dates from archaeological contexts. Eight hundred and eighty-three radiocarbon dates were identified. After completing a chronometric hygiene, a total of 416 radiocarbon dates were then available for use in our Bayesian analysis and simulations. Dates were calibrated using OxCal 4.2.7 and the IntCal 20 curve then compared with simulated dates for commonly recognized archaeological periods in the Western Pyrenees. The simulation results offer a coherent framework for improving the chronological models and defensible radiometric evidence for the onset, duration, and decline of various cultural historical phenomena in the region. The key finding is that publicly available radiocarbon dates from archaeological contexts in the Western Pyrenees are subject to varying uncertainties that affect their precision and accuracy and limit the questions they are presently suitable for addressing. This points to the importance of increasing access, transparency, and dissemination of archaeological results in the Western Pyrenees in line with Open Science guidelines.

Radiocarbon dating and Hallstatt chronology: a Bayesian chronological model for the burial sequence at Dietfurt an der Altm\xfchl \u2018Tennisplatz\u2019, Bavaria, Germany

This study is first attempt to refine Early Iron Age absolute chronology, specifically the timing of the Hallstatt C-D transition in southern Germany, using Bayesian chronological modelling of radiocarbon (14C) dates. The Hallstatt period (c.800–450 BC) marks the transition from prehistory to proto-history in Central Europe. The relative chronological framework for Hallstatt burials developed by the mid-twentieth century is still used today, but absolute dating is limited by the scarcity of dendrochronological dates and the perception that 14C dating in the Hallstatt period (HaC-HaD) is futile, due to the calibration plateau between c.750 and 400 cal BC. We present new AMS 14C dates on 16 HaC-HaD burials from a stratified sequence at Dietfurt an der Altmühl ‘Tennisplatz’ (Bavaria, Germany). This sequence is situated entirely on the ‘Hallstatt plateau’, but by combining 14C dating with osteological, stratigraphic, and typological information, we demonstrate that the plateau is no longer the ‘catastrophe’ for archaeological chronology once envisaged. Taking into account dendrochronological dating elsewhere, we show that at Dietfurt, the HaC-HaD transition almost certainly occurred before 650 cal BC, and most likely between 685 and 655 cal BC (68.3% probability), several decades earlier than usually assumed. We confirm the accuracy and robustness of this estimate by sensitivity testing. We suggest that it is now possible, and essential, to exploit the increased precision offered by AMS measurement and the IntCal20 14C calibration curve to re-evaluate absolute chronologies in Early Iron Age Europe and equivalent periods in other regions.

The Coordination of Chronology in Archaeology on the Period of the Three Kingdoms through the Comparison of Harnesses between Korea and China

삼국시대 동아시아 마구는 전체적인 변화 발전의 틀에서 많은 공통속성이 확인되어 표준연대자료의 확보에유효하다. 양진-16국시대의 마구를 검토하여 편년의 기준자료를 확보하고 이를 삼국시대 마구와 비교하여 삼국시대 고고학 편년 조율을 시도하였다. 동오·서진 마구에서 등자의 발명은 마구 역사에서 획을 긋는 사건이었으며, 등자와 고안교 안장의 조합은 1인기승의 보편화를 의미한다. 동진대에는 쌍등과 고안교 안장의 조합으로 개마중갑기병이 확산하는 틀이 마련되었고, 1인 기승 마장 체제를 확립하였다. 16국 시기 삼연 마구는 전통적 속성, 중원적 속성 및 중원 마구가 삼연 문화 체제 내에서 변용된 속성으로 나눌 수 있는데, 중원을 원향으로 하는 중원적 속성과 변용적 속성이 대부분이다. 금동제 등자, 쌍봉문과 승문을시문한 행엽과 안장 장식 및 판비는 중원을 원향으로 하는 마구 속성이다. 삼연 마구의 경우 삼국시대 등자의 시원인 금속판으로 보강한 목심 등자를 비롯하여 지판과 장식판을 덧댄 구조의 판비와 행엽은 상한이 370년대로편년된다. 중원지역에서 철제 개마중갑기병은 16국 시기에 본격화하였다. 마주의 비교에서 고구려와 가야는 각각 4세기 중엽과 4세기 말에 전연의 것을 받아들였지만, 고구려는 4세기 말에 중원의 것도 수용하여 고구려 독자의 양식을 완성하였다. 가야와 신라는 광개토왕 경자년 남정을 계기로 마갑과 마주 조합이 완비된 개마중갑기병 체제를 갖추었다. 양진-16국시대 마구와 삼국시대 마구를 비교한 결과, 권운문와당의 간지 기년을 4세기 전반으로 한 고구려 고고학 편년, 가락동 2호분의 조영 시점을 3세기 후반으로 하는 백제 고고학 편년, 황남대총 남분을 내물왕 무덤으로 비정한 신라 고고학 편년을 당해 시기 한·중 마구에 적용하면 동아시아 고대 마구의 역사는 물론 세계 마구의역사도 다시 써야 한다. 그렇지만 권운문와당 간지 기년을 4세기 후반, 가락동 2호분을 4세기 말, 황남대총 남분을 눌지왕 무덤으로 하는 편년을 양진-16국시대 중국 마구 편년에 적용하면 괴리가 거의 없다.The harness, which was used in East Asia during the period of the Three Kingdoms, has been confirmed to have many common attributes in terms of the overall framework of changes and developments, showing that it is valid for obtaining data on standard chronology. It has obtained reference data for chronology by reviewing the harnesses of East and West Jin Dynasty-16Guo Dynasty for comparison with those of the period of the Three Kingdoms, which led to an attempt to coordinate chronology in archaeology on the period of the Three Kingdoms. The invention of stirrups in the East Wu·West Jin harness was an epoch-making event in the harness history, and the combination of stirrups and high saddles means the generalization of single-person horse riding. The framework for the spread of the heavy cavalry was established by a combination of the double-stirrups and high saddles in East Jin, resulting in establishing the system of single-person horse riding. The attributes of SanYan harness of 16Guo Dynasty are divided into a traditional attribute, a Chinese Zhongyuan-based attribute, and a transformational attribute of the Chinese Zhongyuan harness transformed within the system of SanYan culture, but in most cases, the Chinese Zhongyuan-based attribute according to the Chinese Zhongyuan region and the transformational attribute apply. gilt-bronze stirrups, Harness pendants decorated with two phoenixes, etc., saddle ornaments, horse bits are the representative examples of harness attributes in the Chinese Zhongyuan region. In the case of the SanYan harness, all of the horse bits and harness pendants structuralized by plates and ornamental plates, including wooden stirrups reinforced by the metal place, the origin of stirrups during the period of the Three Kingdoms, are known to be in the 370s as terminus post quem. In the Chinese Zhongyuan region, heavy cavalry began in earnest in the 16Guo Dynasty. The comparison of horse helmets have shown that Goguryeo and Gaya accepted the ways of QianYan in the mid-4th century and late 4th century, respectively, but Goguryeo completed its own style by accepting those of the Chinese Zhongyuan region in the late 4th century. Gaya and Silla established a system of heavy cavalry with a complete combination of horse armors and helmets with Goguryeo’s southward conquest as a momentum. The results of comparing the harness of East and West Jin-Dynasty-16Guo Dynasty with that of the Three Kingdoms have suggested that applying chronology on the Goguryeo archaeology in which the GanJi (干支) script of cloud-pattern the roof-end tiles was from the first half of the 4th century, chronology on the Baekje archaeology in which the construction period of Garakdong Tomb No.2 were from the late 3rd century, and chronology on the Silla archaeology in which Hwangnamdaechong nambun was designated as the tomb of King Namul to the harnesses of Korea and China in those days, not only the history of ancient harnesses in East Asia, but also that of harnesses in the world should be written. But, applying chronology on the GanJi (干支) script of cloud-pattern the roof-end tiles from the late 4th century, on Garak-dong Tomb No.2 from the end of the 4th century, and on Hwangnamdaechong nambun designated as the tomb of King Nulji to chronology on the Chinese harness in East and West Jin Dynasty-16Guo Dynasty, there is almost no gap among them.

Technocomplexes and chronostratigraphy for MIS 6-1 in southern Africa

AbstractOne of the conventional ways to construct Late Quaternary chronostratigraphic frameworks for archaeology in southern Africa is through archaeological technocomplexes. This practice is more developed in South Africa and Lesotho than in the northern areas of the region. The Still Bay, Howiesons Poort, Robberg, Oakhurst, and Wilton technocomplexes are widely recognized, whereas more ambiguity is associated with the Bambata, Tshangula, Pietersburg, Mossel Bay, Sibudu, Sibudan and early Later Stone Age. Technocomplexes are frequently defined in relation to generalized, typological attributes from lithic assemblages excavated over several decades at different sites with various levels of resolution. This might lead to coarse-level data that do not necessarily relate to changes in culture, cognition, climate or the environment. Here the relationship between lithic technology and the palaeoenvironment is explored from a constrained chronostratigraphic context in two technocomplexes from the southern Cape coast, the Mossel Bay from Klasies River Main site, and the Oakhurst from Klipdrift Cave. Significant changes in the shore habitat are not reflected at technocomplex level, but lithic densities and dimensions of the products vary more closely with environmental shifts. Although a close relationship between Marine Isotope Stages and technocomplexes cannot be unambiguously demonstrated, some aspects of lithic technology seem to be sensitive to palaeoenvironmental change. Technocomplexes have heuristic value to identify cultural patterns through time and space and they are useful in determining where gaps in evidence occur. Ordering stone tool assemblages using technocomplexes remains one of the main ways to construct archaeological chronologies, especially when refined dating results are not available, and for exploring archaeological cultural developments against the backdrop of paleoclimate fluctuations, especially between MIS 6 and 1.

The Colors of the Circus Mosaic from Barcino (Roman Barcelona): Characterization, Provenance, and Technology Issues

Archaeometric studies on mosaics often concentrate only on glass tesserae, while comprehensive studies including both stone and glass tesserae are scarce; however, both types of tesserae can sometimes bring relevant data to elaborate archaeological knowledge on a studied mosaic. In this paper, a representative set of tesserae from a large polychrome Roman mosaic retrieved in Barcelona (NE Spain) is investigated using various methods. Most of the techniques were directly applied on samples prepared as petrographic thin sections (including polarized-light, cathodoluminescence and electron microscopies, and synchrotron through-the-substrate μX-ray diffraction). The results indicate that, from the ten sampled stone tesserae, there are (i) seven limestones, one of them identified as Alveolina limestone (early Eocene) from the southern Pyrenees (ii) two sandstones from Barcelona’s Montjuïc hill (Miocene) and, (iii) a Carrara white marble from the Apuan Alps (Italy). The profuse presence of tesserae of both local and imported materials with well-known uses in architecture, epigraphy, and sculpture could imply that tesserae were a by-product of their main use. Two different production technologies were identified for the three sampled glass tesserae. The concurrent use of antimony- and tin-based opacifiers is in agreement with the accepted archaeological chronology of the mosaic (4th century AD).

Social Identity and Dental Modification at the Postclassic Maya Urban Centre of Mayapan

Dental modification represents one interesting aspect of corporeal adornment in human history that directly reflects personal social identity. Tooth filing choices distinguished certain individuals at the urban, Maya political capital of Mayapan from 1150 to 1450ad, along with cranial modification, nose and ear piercings, tattoos and body paint. Here we examine how filing teeth, considered a beautification practice for women at Spanish Contact in the sixteenth century, is distributed across a skeletal sample of males, females, elites and commoners in this city. We evaluate the normative claim of the Colonial period and determine that while predominantly females filed their teeth, most women chose not to. Sculptural art further reveals that male personages associated with the city's feathered serpent priesthood exhibited filed teeth, and we explore the symbolic meaning of filed tooth shape. Assessing the practice in terms of associated archaeological contexts, chronology and bone chemistry reveals that it did not correlate with social class, dietary differences, or birthplace. Residents of Mayapan, a densely inhabited, multi-ethnic city of 20,000, engaged with multiple material expressions of belonging to intersecting imagined communities that crosscut competing influences of polity, city, hometown and family scale identity. Tooth filing reflects identities at the individual or family scale.

CLARIFYING THE AGE OF INITIAL SETTLEMENT HORIZON IN THE MARIANA ISLANDS AND THE IMPACT OF HARD WATER: A RESPONSE TO CARSON (2020)

ABSTRACTThis paper is a response to criticism by Carson (2020) concerning the age of the Unai Bapot archaeological site in the Mariana Islands. Of specific contention are supposed errors in the marine radiocarbon (14C) research reported by Petchey et al. (2017). According to Carson, this work produced marine reservoir offsets (ΔR) of “suspiciously wide variance from each other … and those results were incompatible with the site’s reported stratigraphy and dating (Carson 2008) as well as with other previously calculated marine reservoir corrections in the Mariana Islands (Carson 2010: 3).” This statement is misleading on all three points. Our reply discusses the problems encountered when dating shells from near-shore “marine” environments where terrestrial input, in particular hard water, may complicate date interpretation. We outline a cautionary tale relevant to any researcher using “marine” shell dates to develop regional archaeological chronologies in regions dominated by limestone.

Revision of the human’s occupations chronologies at the Senegalese and Mauritania sites by using marine reservoir ages corrections

Abstract The prehistoric settlement of the west coast of the Senegalese-Mauritanian basin is established from archaeological remains and coal samples collected, sometimes in a stratigraphic context. However, the chronology issued, in the Before Present (BP) age, does not take into account the taphonomic context of the sites and the local reservoir age. Therefore, this article revisits the chronologies obtained based on the 14C literature and dating(s) acquired. Changes in time and duration of human occupancy of the area are shorter or longer depending on adequate yields of local reservoir age (Ndeye, 2008), which is a relevant element for marine samples. Thus, the archaeological implications observed with the reservoir effect are the rejuvenation or ageing of the dates, the age of the sites, the duration of occupation prehistoric or historical sites studied. Using the calibration programmes, it is noted that for the site of Senegal (Khant), without taking into account the reservoir effect, the human occupation is a priori, from the fifth millennium (Ancient Neolithic) to the third millennium BC (Middle Neolithic). However, if this marine reservoir effect is applied, the chronological periodisation goes from the fourth millennium to the first millennium. For the Mauritanian sites, the reservoir age correction is necessary for the Chami site while for the Tintan site is not required. Therefore, the calibrated archaeological chronologies obtained after the application of the marine reservoir effect are more relevant.