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Speleothem samples collected for dating Palaeolithic cave art in Shulgan-Tash cave and for paleoclimate research in Southern Ural in 2013-2017 6/20/2018 Technical report Yuri Dublyansky* and Yuri Lyakhnitsky** * Institute of Geology, Innsbruck University, Innrain 52, 6020 Innsbruck, Austria ** A.P. Karpinsky Russian Geological Research Institute (VSEGEI), Sredny prospect 74, 199106 St.-Petersburg, Russia Aknowledgment Work described in this report was partly funded by a grant of the Head of Government of Republic of Bashkortostan R. Khamitov through the State Organization “Scientific-Production Centre for Protection and Use of Objects of Cultural Heritage”, Ministry of Culture of the Republic of Bashkortostan. Additional funding was provided through FWF (Austria) grants P257160 and I027070 to YD. Cite this dataset Dublyansky, Yuri; Lyakhnitsky, Yuri (2018), “Description of speleothem samples collected for U- series dating of Paleolithic cave art in Shulgan-Tash cave, Southern Ural, Russia”, Mendeley Data, v1 http://dx.doi.org/10.17632/c85nth69rb.1 Fig. 1. Google Earth satellite image showing locations of caves from which samples were collected. Coordinates of the center of this map are: 53.03 N, 57.05 E. All caves are located in Southern Ural, Russia. 1. INTRODUCTION Location of caves is shown in Fig. 1. In this report we document: (a) sampling of flowstonein Shulgan- 2. SAMPLING PURPOSES Tash cave for the purpose of dating AND STRATEGIES Palaeolithic parietal art; (b) sampling of stalagmites in Shulgan- 2.1. Sampling flowstone for Tash, Kulyurtamak, Victoria, and dating Palaeolithic Gryoz caves for paleoclimate and cave art paleoenvironmental studies 230 (c) sampling of cryogenic cave calcite The Th-U method has recently emerged as (CCC) in Shulgan-Tash and Victoria a unique tool for accurately and precisely caves for paleoclimate and paleo- dating cave art in the presence of calcite permafrost studies. flowstone (Pike et al. 2012; Aubert et al. 2014; Pons-Branchu et al. 2014; Hoffmann et al. 2016, 2018). If the painting was made on flowstone, the 230Th-U age of the latter provides the maximum possible age of the painting (terminus post quem). If the painting is covered by a younger flowstone, the age of the latter constrains the minimum age 3 | P a g e (terminus ante quem) of the art. The shorter the time gap between the deposition of the underlying “canvas” flowstone and the overlying flowstone, the more precise is the dating of the art. Hellstrom (2012) pointed out that any one calcite overgrowth or underlying layer has a relatively low probability of approaching the age of the art. Studies that consider a small number of examples of cave art may therefore return ages that do not lead to a refinement of the age of that art. Our strategy of sampling the parietal art in Shulgan-Tash cave was to strive to identify all potentially datable paintings in the cave (i.e., those made on old flowstone, those that Fig. 2. Spatio-temporal relationships of flowstone were overgrown by younger flowstone, and and pigment of cave art in Shulgan-Tash cave. a – combinations of both). Typical relationships flowstone and pigment are not in contact; b – flowstone is younger that pigment; c, d – between pigment of paintings and flowstone flowstone is older than pigment; e, f – flowstone are depicted in Fig. 2. is both older and younger than pigment; g – flowstone, both older and younger than pigment, To ascertain that flowstone at a potential is overgrown by a thick layer of tufaceous calcite. sampling location has an unambiguous Red rectangles show possible strategies of stratigraphic relationship with the painting sampling. Note that in a the temporal relationships between paintings and flowstone are each potential location was inspected with a indeterminate, and dating will not yield hand lens. information on the age of cave art. Cave-wide inspections have shown that paintings at the upper level of the cave (Hall 2.2. Sampling stalagmites of Paintings) were made on barren cave for paleoclimate and walls, and only paintings located at the lower paleoenvironmental level of the cave (Domed Hall, Hall of Signs, and Hall of Chaos) have clear stratigraphic studies relationship with flowstone. In total, we “Common” speleothems, such as stalagmites identified and sampled 20 sites potentially and flowstone are recognized archives for suitable for parietal art dating. paleoclimate studies (e.g., 18O and 13C of calcite, 2H of fluid inclusion water, trace elements, etc.; Fairchild and Baker, 2012). For specific purpose of this project, speleothems were 230Th-U dated at their tops and bottoms, thus constraining the time of infiltration of water into the cave (i.e., permafrost-free conditions). Cryogenic cave carbonates (CCC) provide information on the 4 | P a g e time of occurrence of (degrading) permafrost older and younger flowstone layers, in the study area. sometimes having complex geometry (Fig. 2 e). Sampling of speleothems was preceded by screening of caves in the area, during which 3.2. Small-diameter cores the caves were visited, inspected and sites (cave art dating) potentially suitable for speleothem collection identified. By visual observations we 10 mm-diameter holes were drilled through attempted to identify stalagmites that grew the flowstone using custom-made water- at different times, thus providing the widest cooled diamond drill bits, yielding 8 mm- temporal coverage of speleothem growth. In diameter cores. In most cases cores were order to improve robustness of the record, taken laterally adjacent to the paintings, so we collected 14 stalagmites from four caves that the paint layer was not intersected. This located within 4 km (Fig. 1). technique proved adequate when paintings were made directly on cave walls and were 2.3. Sampling cryogenic overgrown by younger calcite. In cases cave carbonates (CCC) where a pigment layer was “sandwiched” between the older and the younger CCC were not known from the study area flowstone, particularly when the shape and prior to this work. We performed a targeted thickness of growth layers were both search for CCC in all inspected caves. CCC irregular, sub-sampling of pre- and post-paint were found and sampled in two caves, calcite in the laboratory becomes Shulgan-Tash and Victoria. problematic. In a number of cases, therefore, we had to drill cores across the pigment 3. FIELD SAMPLING layer. This technique was approved by the oversight authority, State Organization 3.1. In situ collection of “Centre for the protection and management powders using a hand- of immovable cultural heritage” of the held milling device Ministry of Culture, Republic of (cave art dating) Bashkortostan, Russia. Samples for dating were collected as We concur with Hoffman et al. (2016) that powders using a hand-held milling device by the use of this sampling technique should be carefully removing ca 0.5 mm-thin individual restricted to the most exceptional layers of calcite. This technique allowed circumstances and should, in general, be sampling sites showing a simple flat discouraged. geometry of the flowstone growth layers (cf. Fig. 2 b-d). The approach becomes 3.3. Patching problematic when: (a) paintings were made In order to preserve the visual integrity of on irregular flowstone surfaces (e.g., runnel the paintings and cave formations the small flowstone; Fig. 2 f); (b) paintings are coated holes produced by coring were patched with by thick tufaceous calcite (Fig. 2 g; at some lime putty and the addition of local sand and sites in the Hall of Chaos the thickness of puzzolana. Subsequently, patches were such calcite overgrowth reaches 2 cm); and camouflaged using local natural materials (c) paintings are “sandwiched” between (Fig. 3). 5 | P a g e 3.4. Sampling entire speleothems (paleoclimate studies) Stalagmites were collected in those parts of the caves where their removal caused minimal visual impact. Whenever possible, naturally broken stalagmites were collected. Samples of cryogenic cave calcite (CCC) were taken by collecting between 10 and 100 g of crystals and aggregates from the cave floor (Fig. 4). 4. FIELD SAMPLING SCHEDULE Sampling of calcite associated with Palaeolithic cave art in Shulgan-Tash cave was carried out in three stages. Stage 1. Pilot sampling was carried in June 2013. The aim of this campaign was to Fig. 3. Patching and camouflaging the holes: determine whether calcite underlying and (a) 10 mm-diameter hole patched with lime putty; overgrowing cave art is datable using the (b) the hole was subsequently camouflaged with 230Th-U method. At this stage, several local clay. powder samples were collected using a growth layers and the lack of a marker hand-held milling device. horizon between the two stages of calcite deposition. Upon obtaining permission from Stage 2. The main sampling was carried out the overseeing authorities, we drilled several in June 2015. In most cases sampling was cores across the paint layers. In addition, done by small-diameter coring through several new sites were sampled in the Hall of flowstone adjacent to paintings. In two cases, samples represented fragments of runnel flowstone which were chipped off the wall with a scalpel (outside the painted area). Stage 3. Additional sampling was carried out in November 2015. Several sites, where initial sampling by coring adjacent to the painted area had yielded unsatisfactory dating results, were re-sampled. In these cases we were not able to clearly separate sub- samples of pre- and post-paint calcite Fig. 4. Collection of cryogenic cave calcite in the Hall of Rainbow, Shulgan-Tash cave. Photo R. Shone. due to the complex geometry of 6 | P a g e Signs. Sampling of stalagmites and CCC was carried out on several field expeditions between 2013 and 2017. 5. LABORATORY SUB- SAMPLING Samples, collected in situ as powders, were subjected to dating as is.

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