Reference Chronology Research Articles

Age validation of yellowfin and bigeye tuna using post-peak bomb radiocarbon dating confirms long lifespans in the western and central Pacific Ocean

Abstract Age-reading protocols for tuna species using annual growth zones in thin-cut transverse otolith sections have produced greater age estimates than previous methods. Lifespan estimates for yellowfin (YFT) and bigeye (BET) tuna (Thunnus albacares and T. obesus) were validated up to 16–18 years in the western North Atlantic Ocean using bomb 14C dating and the current study extends the approach to YFT and BET of the western and central Pacific Ocean (WCPO). Archived otoliths from young-of-the-year (YOY) tuna caught in the WCPO were analysed for 14C to establish a reference chronology covering 30 years (1989–2019). This YOY 14C time series exhibited strong concordance with existing coral-otolith 14C references for the tropical-subtropical Pacific Ocean and was combined as a single chronology. Otolith cores from YFT aged 1–14 years and BET aged 1–13 years from presumed annual counts were analysed for 14C. These measurements aligned with the reference chronology for the calculated hatch years for both species. These findings provide strong evidence that growth zones in thin-sectioned otoliths are deposited annually for YFT and BET of the WCPO and that age interpretation is correct using the current age reading protocol with little to no bias.

Dendrochronological examination of the Assumption of the Virgin Mary orthodox church in the village of Pades, Greece

The current study is a dendrochronological analysis of the wood from the church of the Assumption of the Virgin Mary, Pades, Greece which was built towards the end of the 18th century according to historical sources. The tree-ring analysis shows that the date, 1784, given on the inscription at the main entrance of the church probably documents the year when the construction works began, and that there were several construction stages of the structural and decorative elements of the church until the early 19th century. Moreover, the oldest (reused) timber elements that were identified through the dendrochronological study date back to the first half of the 15th century and may indicate the first traces of the construction activity in and around Pades. The dendrochronological study enabled the development of three local reference chronologies for the Epirus region. The timespan for the developed chronologies for the church in Pades is: 1262–1825 for Pinus heldreichii (Bosnian pine), 1295–1854 for Pinus nigra (Black pine), and 1571–1767 for Quercus sp. (Deciduous oak).

Age validation of yellowfin tuna Thunnus albacares in the Indian Ocean using post-peak bomb radiocarbon chronologies

Yellowfin tuna Thunnus albacares stock assessments use age-structured models; therefore, accurate methods for ageing the catch are required. Age estimation techniques need to be validated at the population level to ensure accuracy. However, otolith-based age estimates of yellowfin tuna have never been validated in the Indian Ocean. The current study provides the first age validation for Indian Ocean yellowfin tuna using the post-peak decline period of the bomb radiocarbon (14C) chronometer. A 14C reference chronology based on accelerator mass spectrometry assays of known-age yellowfin tuna otoliths was consistent with published regional coral records, with all showing similar rates of decline during the 2000 to 2019 study period. After back-calculating the birth years of sub-adult and adult yellowfin tuna from otolith increment counts, Δ14C values measured in the early growth portion of the otolith were compared with the observed decline slope of the reference chronology. There were no significant differences between the birth years of validation and reference samples, supporting the otolith increment age determination methodology between the ages of 2.2 and 10.5 yr. The validation of age and growth estimates is expected to benefit assessment models for Indian Ocean yellowfin tuna. We recommend that otoliths from large fish continue to be collected to expand the validation to older fish. Greater precision in the validation results will also require a larger reference chronology.

Flood events in the lower reaches of the Yellow River: OSL and radiocarbon dating on the Anshang site

The lower reaches of the Yellow River have witnessed numerous episodes of flooding and considerable shifts in its course. Examining flood records within the Yellow River basin offers invaluable insights into ancient human settlements, agricultural practices, trade routes, and technological advancements of ancient Chinese civilizations. However, dating these fluvial sediments poses a considerable challenge due to either the scarcity of organic material for radiocarbon (14C) dating or the potential incomplete bleaching of sediments for optically stimulated luminescence (OSL) techniques. This study focused on the Anshang site located in Henan Province, we obtained OSL ages from distinct grain size fractions of quartz and cross-verified them with independent acceleration mass spectrometry (AMS) 14C ages. The findings revealed that both coarse quartz grains (CG) and medium quartz grains (MG) underwent complete bleaching in silt-dominated flood deposits and shallow lacustrine deposits. Conversely, the OSL ages of CG and MG quartz were notably overestimated by approximately 3–6 ka in silty clay-dominated flood deposits. Upon comparing the OSL ages with AMS 14C ages, it was evident that bulk organic matter AMS 14C ages aligned with CG OSL ages in shallow lacustrine deposits, but they appeared older than CG OSL ages in flood deposits. However, the AMS 14C ages from plant demonstrated good consistency. Consequently, we successfully identified flood-lacustrine sediments dating back to approximately ∼13 ka, ∼8–3 ka, ∼2.6 ka, ∼1 ka, and the last few hundred years, aligning well with historical documentation and earlier research. The regional evidence presented herein enhances our understanding of the applicability of OSL dating and AMS 14C dating in fluvial-lacustrine sediments. Armed with these new ages, we constructed a reference chronology for archaeological localities situated in the fluvial sediments of the lower reaches of the Yellow River.

Bomb radiocarbon determines absolute age of adult fin whales, and validates use of earplug growth bands for age determination

Baleen whales are one of the few vertebrate taxa for which there are no confirmed estimates of longevity or methods of age determination. Lamina counts in the waxy earplug are assumed to represent age, but ageing accuracy is completely unknown. In this study, bomb radiocarbon assays of the earplug growth sequence in three adult fin whales (Balaenoptera physalus) were used to prepare the most complete within-individual bomb radiocarbon chronologies yet reported for any vertebrate. The whale radiocarbon chronologies matched those of known-age carbonate reference chronologies very well, indicating that the earplug laminae were both metabolically stable and formed throughout the life of the whale. Earplug lamina counts accurately represented absolute ages of 65-85 yr to within 6% of the correct age. Detection of a significant declining trend in δ13C with year of lamina formation within individual whales was consistent with that of the Suess effect, again underlining the metabolic stability of the earplug laminae. Given our results, recent applications of earplug laminae for reconstructing diet and life history events appear to be firmly based, with the potential for further elemental and isotopic applications analogous to those of the otolith.

What Drives Business Cycles in Egypt? An Analysis of Coincident and Leading Indicators

Abstract The paper proposes a chronology for the Egyptian economy by detecting phases of expansions and recessions during the period (2002–2019). It examines the cyclical behavior of variables that are considered potentially useful in measuring or predicting aggregate economic activity. To do so, we combine the National Bureau of Economic Research (NBER) approach together with time series analysis techniques to select the variables best suitable to play the role of coincident and leading indicators. This methodology is found to be the most appropriate when there is no well-established reference chronology as a benchmark for the cyclical analysis, which is the case of Egypt. As a result, two composite indexes are constructed: 1) the composite index of coincident economic indicators (CEI), which can be considered an adequate measure for the Egyptian business cycle; 2) the composite index of leading economic indicators (LEI) that shows good performance in anticipating aggregate economic activity in Egypt. Moreover, the empirical results indicate that total employment, consumption, and investment move coincidently with the reference cycle, while exchange rate and interest rate variables lead the reference cycle and have strong predictive power for economic activity in Egypt.

Reconstructing the oaks’ growth patterns in Greece with the use of historical timber: Case studies from Western Peloponnese

Southern Greece is a region where available oak reference chronologies are still missing, making dendroarchaeology and dating of historical buildings rather challenging, if not impossible. In the current study we performed wood identification and dendroarchaeological analysis on timber from three historical buildings: the castles of Androusa and Koroni and the Church of Agios Dimitrios, in Western Peloponnese. The three monuments represent buildings of different uses covering different periods, but also sharing a common characteristic: oak was the only timber used in their construction, while the number of preserved timber elements is very limited. A dendroarchaeological examination of these three historical buildings, together with radiocarbon and wiggle-matching analysis, provided valuable chronological information for the local archaeologists, historians, and other scientists. Application of dendrochronological techniques has helped place the three buildings under study into the Ottoman period. Our results also show that timber was acquired most probably from local non-managed forests, which suggests that oak forests were present in the broader area at least from the late 15th to the first half of the 18th centuries. The discordance between dendrochronological and radiocarbon dates in one of the three cases highlights the need for further exploration of the study area through a combined implementation of both dendrochronological and radiocarbon dating analyses in order to develop well-replicated local oak chronologies. Our study also shows that dendroarchaeology can contribute significantly to the cultural and landscape history of Western Peloponnese even with an examination of limited number of preserved timber elements from historical buildings.

Overcoming crossdating challenges to generate ring-width chronologies for Sequoia sempervirens across its native range

We utilize a large dendrochronological dataset for Sequoia sempervirens of 1.29 million rings from 5952 series for 278 trees to generate location and regional ring-width chronologies and to investigate constraints on crossdating. Increment cores were collected at regular height intervals along the trunk via free-hanging ropes with some terrestrial deadwood sampled. Inter-annual chronologies span 86–1687 yr for 47 locations in primary and secondary forests across the native Sequoia range. Shared signals based on declining strength of paired correlations with distance, strong correlations within regions, and groupings of principal components guide chronology creation for northern (1032 yr, 108 trees) and southern (865 yr, 52 trees) regions and four sub-regions. The suite of chronologies provides location-specific references as well as more robust regional indices that reflect distinct signals along a climatically-integrative latitudinal gradient. Secondary forests date to near completion, and we use a subset of data to assess crossdating for trees in primary forests. Among tree and landscape attributes, old age is the most important predictor of undated and missing rings, and undated rings align with periods of reduced biomass production distributed across centuries-long lifespans. Crossdating metrics vary by height above the ground with breast height (BH) and 10 m samples having more undated rings than upper samples. At 10 m, samples have the most missing rings. Buttressing affects the lower trunk as BH series have higher ring widths and lower interseries correlations compared to those up to 70 m. Whole-trunk sampling maximizes success for crossdating old, structurally-complex Sequoia and enables dating of crown damage and assessment of biomass dynamics related to environmental change. Reference chronologies, regional assessments, and crossdating insights collectively guide future study of Sequoia for applications including climatology, fire ecology, and seismology.

Dendrochronological Studies of an Alpine Village (Courbons, Digne-les-Bains, France)

Abstract A dendrochronological study of Courbons, a village in the southern French pre-Alps, was conducted to improve our understanding of its history, strengthen the reference chronologies, and reconstruct the outlines of historical forests. A total of 20 buildings were subjected to dendrochronological sampling. The 145 sampled wood pieces were of nine different species, 44 of which are dated from larch, fir, and deciduous oak. Two main construction phases were identified (from the 13th–16th century CE and from the 18th–20th century CE), separated by a hiatus during the 17th century CE. A scarcity of resources could be the cause of the hiatus. We noticed that oak trees were only used before the 16th century CE and that trees felled after the 17th century CE grew better than those that were felled before this period. Based on historical published data, we assumed that demographic variations, trees reserved for shipbuilding, and pressures from pastoralism could explain the dendrochronological results.

Macroeconomic Determinants of Tourism Demand in Malaysia: A Markov Switching Regression Approach

A wave of studies has always surrounded the nexus of tourism development and economic growth in a nation. An assessment is provided in this study to examine the Malaysian tourism market dynamics. A series of macroeconomic variables has been utilised to model tourism demand and examine causal linkages among tourism and economic growth. Spanning from 2000 till 2018 on a monthly basis, the Markov regime switching regression provides an overview of tourism market performance and potential influences during recession and expansion periods of the Malaysian tourism cycle. Notably, the results present a reference chronology of the crises happening over the past two decades, the Granger causality of the variables, and different behavioural changes of the variables as well for both recession and expansion periods. Significant relationships have been revealed in this study that suggest that overall international tourism can drive economic growth and vice versa.

Dendrochronological Dating and Provenancing of String Instruments.

Dendrochronology, the science of dating tree rings in the wood, defines in which calendar year a particular tree ring was formed. The method can be used to determine the age and authentication of wooden musical instruments. We present a protocol describing how to perform a dendrochronological analysis on stringed instruments and how to interpret the dating. The protocol describes the basic steps in the analysis of top plates, which are usually made of Norway spruce (Picea abies) or, more rarely, silver fir (Abies alba). First, the top plate is carefully inspected, and then the tree ring widths are measured directly on the instrument using high-resolution images. After completing the measurements, a tree ring sequence of the instrument is created, and, in the next step, dating is performed with a number of reference chronologies of the tree species from different geographical areas and instruments. The specialists who date the instruments also invest work in creating reference chronologies. The dendrochronological report provides the dating of an instrument as a calendar year (end date), indicating the year in which the last (most recent) tree ring on the top plate was formed when the tree was still alive. The end date represents the terminus post quem, the year after which the instrument was made or before which it could not have been made. To estimate the year of manufacture, one must consider the time required for wood drying and storing and the number of tree rings removed during wood processing. This protocol is intended to help those commissioning such an analysis to better understand how the analysis is performed and how to interpret the dendrochronological reports in terms of the age, origin, maker, and authenticity of the instrument.

Dendrochronological Dating and Provenancing of String Instruments

Dendrochronology, the science of dating tree rings in the wood, defines in which calendar year a particular tree ring was formed. The method can be used to determine the age and authentication of wooden musical instruments. We present a protocol describing how to perform a dendrochronological analysis on stringed instruments and how to interpret the dating. The protocol describes the basic steps in the analysis of top plates, which are usually made of Norway spruce (Picea abies) or, more rarely, silver fir (Abies alba). First, the top plate is carefully inspected, and then the tree ring widths are measured directly on the instrument using high-resolution images. After completing the measurements, a tree ring sequence of the instrument is created, and, in the next step, dating is performed with a number of reference chronologies of the tree species from different geographical areas and instruments. The specialists who date the instruments also invest work in creating reference chronologies. The dendrochronological report provides the dating of an instrument as a calendar year (end date), indicating the year in which the last (most recent) tree ring on the top plate was formed when the tree was still alive. The end date represents the terminus post quem, the year after which the instrument was made or before which it could not have been made. To estimate the year of manufacture, one must consider the time required for wood drying and storing and the number of tree rings removed during wood processing. This protocol is intended to help those commissioning such an analysis to better understand how the analysis is performed and how to interpret the dendrochronological reports in terms of the age, origin, maker, and authenticity of the instrument.

Occasional but severe: Past debris flows and snow avalanches in the Helmos Mts. (Greece) reconstructed from tree-ring records

The eastern Mediterranean is a hotspot in terms of geomorphic hazards, but the activity of gravitational processes in mountainous areas is largely unexplored. We carried out dendrogeomorphic research in the Helmos Mountains (Northern Peloponnese, Greece) to determine the timing, spatial extent, and hydrometeorological triggers of debris flows and snow avalanches. Specifically, we sampled increment cores from 123 injured Greek firs (Abies cephalonica L.) growing on a debris flow cone and growing along a snow avalanche track. Tree rings were counted and cross-dated with the reference chronology using CooRecorder and CDendro software and the event years were determined on the basis of the location of scars and traumatic resin ducts. We compiled an 118-year chronology (1904–2021) with seven debris flow event years and only one severe debris flow occurring in the 1970/1971 dormant period (WIt = 148.0), followed by spatially limited records for 1986/1987 (WIt = 3.8) and 1993/1994 (WIt = 2.5). Similarly, seven snow avalanche event years were identified in the period 1854–2021, with one major event in 1997/1998 (WIt = 304.5) followed by the 1998/1999 event (WIt = 6.3). Extremely wet conditions in February–March 1971 followed by rain-on-snow precipitation were considered as the most likely trigger of the analysed debris flow event using data from nearby meteorological stations and the ERA5 reanalysis. The snow avalanche event was deciphered in the spring of 1998, when heavy snowfall over three days (62 cm) was followed by rapid snowmelt due to high average temperatures (6–11 °C). We conclude that the abundance of snow is a crucial factor in the geomorphic activity in the study region and that the temperature fluctuations and rain-to-snow transitions are the leading factors for the debris flows or snow avalanches to occur. Furthermore, the dendrogeomorphic approach used can be useful to clearly identify large-scale geomorphic events and excludes potential geomorphic noise caused by other ecological stresses.

Bomb Radiocarbon, Otolith Daily Increments and Length Modes Validate Age Interpretations of Chilean Jack Mackerel (Trachurus murphyi)

Ages of Chilean jack mackerel (Trachurus murphyi) in the southern Pacific Ocean were validated using three methods: 1) daily microincrement readings in sagittal otoliths of young-of-the year (YOY) fish to validate the first annulus; 2) modal progression of strong year-classes (PSYC) to validate the first, second and third annuli, and 3) bomb radiocarbon analysis of otolith cores to validate the absolute age in older fish >38 cm fork length (FL). A Laird-Gompertz (LG) model was fitted to fork length (cm) at age (days) relationship in fish ranging from 3.4 to 25.0 cm FL and from 56 to 550 days in age. The LG model estimated a mean FL of 22 cm at the end of the first year of life, which was large compared with the mean FL estimated through conventional ageing in whole otoliths. The comparison between daily age with annual growth bands from whole otoliths, showed a false increment formed at 185 ± 34 days and a second translucent increment formed at 352 ± 79 days, corresponding to the first annulus for fish with the mean FL of 21.4 ± 1.8 cm. The PSYC coinciding with the recruits of 2008 (age 0), was tracked through three subsequent years with high accuracy, attaining 23, 27 and 30 cm FL in 2009, 2010 and 2011, respectively. These modes identified as age 1, age 2 and age 3 in the PSYC, matched to the mean length of fish with 2, 4 and 5 translucent increments in sagittal otoliths. Results from bomb radiocarbon analysis confirmed that most of the ages were correct, because the Δ14C content of adult otolith core matched the reference chronology. The absolute mean ages for the assayed otoliths, based on the comparison with the reference chronology, ranged from 7 to 13 years for sizes between 39 and 60 cm FL. The age validation for T. murphy as addressed in the current study provided crucial information for enhancing stock assessment output of this important transboundary commercial species.

Dendroclimatic analysis and cartographic modeling of the climatic response of Fagus sylvatica during growth in a sector of the central Cantabrian Mountains

The wide distribution of the common beech (Fagus sylvatica) in Europe reveals its great adaptation to diverse conditions of temperature and humidity. This interesting aspect explains the context of the main objective of this work: to carry out a dendroclimatic analysis of the species Fagus sylvatica in the Polaciones valley (Cantabria), an area of transition with environmental conditions from a characteristic Atlantic type to more Mediterranean, at the southern limit of its growth. The methodology developed is based on the analysis of 25 local chronologies of growth rings sampled at different altitudes along the valley, generating a reference chronology for the study area. Subsequently, the patterns of growth and response to climatic variations are estimated through the response and correlation function, and the most significant monthly variables in the annual growth of the species are obtained. Finally, these are introduced into a Geographic Information System (GIS) where they are cartographically modeled in the altitudinal gradient through multivariate analysis, taking into account the different geographic and topographic variables that influence the zonal variability of the species response. The results of the analyses and cartographic models show which variables are most determinant in the annual growth of the species and the distribution of its climatic response according to the variables considered.

Dendrochronological dating and provenance determination of a 19th century whaler in Patagonia (Puerto Madryn, Argentina)

Dendrochronological methods have been widely used to determine the date of construction and provenance of shipwrecks. Despite a large number of shipwrecks, the application of dendroarchaeological techniques is relatively incipient in the coasts of South America. This paper presents the results of a dendroarchaeological study conducted at the shipwreck site "Bahía Galenses" (BG), located in the western sector of Golfo Nuevo, on the Patagonian coast of the South Atlantic Ocean. Based on previous archaeological research, two hypotheses were tested in this study. First, the wreck described in the BG 2 sub-site corresponds to a mid-19th-century whaler built in the northeastern US. Second, these remains correspond to the Dolphin, a northeastern American whaler built in Warren (Rhode Island) in 1850 and shipwrecked in the Atlantic coast of Patagonia in 1859. Using dendroarchaeological provenance methods and a novel approach based on the gridded North American Drought Atlas, we found highly significant correlations between the wreck's tree-ring width series and white oak and yellow pine tree-ring reference chronologies from the eastern US. The latest non-cutting dates obtained in this analysis correspond to the year 1849. To our knowledge, our study pioneered the use of dendrochronological methods for dating and establishing the provenance of a whaler's remains on the Atlantic coast of South America and encourages the feasibility for future dendroarchaeological research based on the large number of wooden shipwrecks that occurred in the region.

Discovering the Unknown History of the Utilization of Pinus heldreichii in Wooden Structures by Means of Dendroarchaeology: A Case Study from Metsovo (Northern Greece)

(1) Background: Pinus heldreichii is a long-living tree subalpine species commonly used for climate reconstruction. Nevertheless, its potential for dendroarchaeology and dating of historical timber remains unknown. In Metsovo and in the surrounding area of Pindus National Park (Northern Greece) it is commonly used for the construction of buildings and wooden objects and artifacts. (2) Methods: We examined timber found in historical buildings within the study area and we tried to date it using local reference chronologies of Bosnian and Black pines. (3) Results: Bosnian pine chronologies can be used to date timber from historical buildings, while they can also be used as reference chronologies against Black pines, giving very high cross-dating values. Therefore, and since the macroscopic identification of the two species’ timber is impossible, the analysis of wood anatomy is necessary to distinguish the two species in the case of historical wood. (4) Conclusions: The current paper presents the first application of dendroarchaeology for Bosnian pine and highlights the potential of the species in studying cultural heritage and the human past.

Dropped in the Ocean – 87Sr/86Sr as a provenance tool for ice-rafted Arctic driftwood

Provenance and age determinations of driftwood provide insights into Holocene Arctic Ocean surface currents and sea ice dynamics, with detailed reconstructions requiring a provenance methodology with fine temporal and spatial resolution. Determination of wood geographical provenance by genus data is limited by its spatially coarse resolution, while provenance by dendrochronological crossdating is reliant on available boreal forest reference chronologies which are abundant for recent centuries but more sparse for older periods of the Holocene. We present the development of novel techniques to refine the provenance of driftwood through radiogenic isotopic analysis ( 87 Sr/ 86 Sr). The use of geochemical techniques addresses limitations of current methods and opens the possibility of defining the role of atmospheric and oceanic circulation in sea ice and climatic changes throughout the Holocene at a finer spatial resolution than currently possible. This study investigates and develops geochemical 87 Sr/ 86 Sr fingerprinting of Arctic driftwood. To this end, it analyses driftwood samples from northern Svalbard and compares this technique with provenance regions obtained through dendrochronology, and with modelled and measured global 87 Sr/ 86 Sr reference databases. We conclude that the utilisation of 87 Sr/ 86 Sr ratios to establish provenance for Arctic driftwood has some potential, but identify important limitations in the method, concerning both the signal in samples and reference values required for provenance. Increased sample populations and source samples for calibration, as well as methodological improvements that address the likely overprinting linked to driftwood transport, are recommended to build upon this work. We conclude that at present dendro-provenancing continues to be the most powerful method to study sea ice dynamics from Arctic driftwood and suggest that given the high spatial granularity of 87 Sr/ 86 Sr across the boreal forest, this technique might only be usable in combination with previously developed provenance tools and reconstructions. This study provides a first step in the use of radiogenic isotopic analysis in a multi-proxy reconstruction of Holocene driftwood incursion onto high Arctic shorelines. • Driftwood is a novel tool for insights into Holocene Arctic sea ice dynamics. • Fine spatial and temporal resolution of driftwood provenance is needed. • Geochemical 87 Sr/ 86 Sr fingerprinting of Arctic driftwood is explored in this study. • 87 Sr/ 86 Sr shows some promise, with limitations in reference data and sample signals. • We conclude that a combined approach to driftwood provenance shows the most promise.

Absolute Age Determinations of Rural Basque Furniture Using Dendrochronology: A Pilot Study of Four Granary Chests and a Wardrobe

Dendrochronological research in NW Spain is aimed at developing reference chronologies of oak (Quercus sp.), which are suitable for absolute age determinations of cultural heritage from the Basque Country. So far, the main research interest has been on rural architecture such as farmhouses and barns. In order to extend the application range of Basque dendrochronology, the current study focuses on tree-ring research of rural furniture. In close consultation with the curators of cultural centre Gordailu (Irun), four granary chests and a wardrobe were selected for this pilot study. The tree-ring patterns of these objects significantly match against the new Basque reference chronologies, yielding absolute calendar years for the studied panels. The last-formed measured ring from the oldest granary chest in this collection dates to AD 1517. The other three chests have last-formed rings dating to AD 1580, 1665 and 1829, and the wardrobe has a last-formed ring dating to AD 1439. Sapwood ring counts from living oaks in this region were used to estimate the number of sapwood rings missing on the outside of the panels. Derived absolute and terminus post quem felling dates of wood were further refined by adding the estimated drying time of the wood based on information derived from traditional carpenters in this area. All dendrochronologically established construction dates constitute a correction or refinement of the original art-historical age determinations. In addition, the previously assigned provenance of one granary chest could be corrected. These results indicate that dendrochronology is an excellent method to refine our knowledge about the age, and in some cases the exact geographical provenance, of rural movable heritage in and from the Basque region. The fact that the previously established provenance of four of the studied objects within the Basque Country could not be refined further implies that most Basque reference chronologies at present are not sufficiently specific for assessing wood provenance on an intra-regional scale. This can be solved in the future by reassembling the data underlying these chronologies into homogeneous timber groups covering smaller, ecologically more similar, geographical growth areas.

A case study on geomorphology: Tree-ring-based confirmation of the formation year of Lake Kaindy after the 1911 Kemin earthquake in Almaty (Kazakhstan)

Lake Kaindy, which is located in the Kazakhstan side of the Tien Shan Mountains is one of the most famous places in the World due to having sunken Picea schrenkiana Fisch. & C.A.Mey. trees within the Lake. The purpose of the study is to find the dead years of the sunken trees in the lake and therefore to confirm the formation time of Kaindy Lake, and if there is an effect of the 1911 Kemin earthquake on the tree-ring width of Picea schrenkiana around the lake. Eight wood pieces and two increment cores from the sunken trees were taken to find the formation time of the lake. For building a reference chronology to date these sunken woods, a total of 43 increment cores from 25 trees of Picea schrenkiana were extracted by using an increment borer 50 cm long. Four sunken trees were dated to 1912, and dating statistics which are Gleichlaufigkeit value (percentage of parallel variation), t-tests (TV, TVB, TVBP), and CDI (crossdating index) were calculated as 74%(***), 3.3(**), 7.9(***), 9.7(***) and 57, respectively, and all are significant. According to the 11-year event analysis, the ratio of decrease after the earthquake is 34% in older trees, and 20% in younger ones. One of the main reasons for long-term decreasing growth may be breaking the root tips and dying the roots with the effect of the violent vibration in the earthquake. With this dendrogeomorphological study, the formation date of Lake Kaindy was determined as 1911 and the local information was confirmed with tree-ring data. After the year of the great earthquake, a long-term dry period occurred up to the years of 1930s. Tree-ring results showed that the affected trees from the earthquake produced narrower rings during this dry period.