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Content available remote Are fossils enough? Palaeontological tourism based on local dinosaur discoveries
Fossils of dinosaurs and other tetrapods have long aroused interest of scientists and the public opinion alike. Every finding of a new (especially large) species receives coverage in national and international media, and thus, local fossil discoveries might constitute a good basis for local tourism development. The paper aims to examine whether fossiliferous sites on their own may be enough for the development of palaeontological tourism to occur, or do they require the support of additional amusement infrastructure. For this purpose, the interest in chosen localities was analysed using Google and Wikipedia searches, and was further discussed against a survey on dinoparks and their elements. The above-mentioned data reveal that local tourism can be indeed predicated on local paleontological findings, however, it is deemed considerably more efficient if such attractions are backed with an extensive infrastructure of amusement theme parks.
Infrared absorption spectroscopy was introduced at the Museum of the Earth of the Polish Academy of Sciences in Warsaw in 1985for research on fossil and subfossil resins of the world. As new reports on previously unknown findings have been made, a collection of resins from across the world has been developed according to the identifications based on the preliminary IRS method, documented by a catalogue of about 1200IR spectra, of which 344 are presented in the published ATLAS. The results of research, conducted with the participation of various teams, are presented. These include very useful activities that organize the terminology to protect against counterfeiting, and indications of the areas of differentiation of highly resin-producing forest communities, both in time and with regard to their migration over considerable distances. In search for the source tree of succinite, Pseu- dolarix vehri has been indicated based on both the IR spectra from Axel Heiberg (Canada) and the Paleogene paleogeography. In the studies of Indonesian glessites, the hypothesis of the contribution of volcanic processes to increased production of resin by trees has been proved. In amber (= succinite) with a solidfoam structure, SEM investigations revealed the presence of succinellite microcrystals (= succinic acid), hitherto known only as one of the components of dry distillation of the Baltic amber.
The occurrence of perylene in the Middle Jurassic fossil wood from Poland is described, along with its correlation with unsubstituted polycyclic aromatic hydrocarbons (PAHs) as well as cellulose content. Perylene is especially common in immature/low maturity organic matter (OM), largely of terrestrial origin (e.g. Louda & Baker 1984, Jiang et al. 2000, Grice et al. 2009). It has been found in diverse recent environments, such as marine and terrestrial sediments, including peats, as well as ancient deposits, including brown coal and hard coal, crude oil and sedimentary rocks (review in Marynowski et al. 2013). Here we link perylene, a product of wood-degrading fungi, to conifer biomarkers in fossil wood material of different ages. Middle Jurassic wood remnants were of relatively low maturity (ca. 0.2-0.4% vitrinite reflectance Rr), had excellent preservation of biomarkers and biomolecules and generally good preservation of anatomical structures due to early diagenetic mineralisation. The results from described (most taxonomically defined) fossil wood fragments demonstrated a negative correlation between the concentration of perylene and those of generally typical conifer biomarkers (e.g. cadalene, dehydroabietane, simonellite and retene). We defined a conifer wood degradation index as: CWDI = perylene / (perylene + cadalene + retene + simonellite + dehydroabietane); and observed a wide range of values (0.001 for less degraded wood to 0.95 for highly degraded samples). We determined similar δ13C values for perylene from the fossil wood samples (from -26.4% to -27.8%), whereas the values for the conifer biomarkers were slightly higher and varied from -25.6% to -26.6%. In contrast, pyrene was depleted in 13C (from -27.5% to -28.2%). The carbon isotope values of perylene are consistent with an origin from wood-degrading fungi.
The geological profile of Quaternary deposits was excavated at the northern district of the city of Wrocław in an artificial ditch of about 200 m long and 6 m deep. Lower part of the profile, starting from the depth of 3,2 m below the surface down to the base of the ditch consisted of light-yellow sand with partly fragmented intercalations of plant debris (0,2 m thick) at the depth of 4,0 m. The lowermost bed of plant debris marks the same level in which numerous logs of sub-fossil oak (Quercus robur) were found. The excavations along the ditch revealed 22 such logs, the thickness of which is in rang of 0,4-1,4 m. They occurred at the depth of 3,9-5,4 m. Morphology, color and qualities of the sub-fossil wood were very good indicators of the changing conditions of the river transport and sedimentation. Among the dendrochronologically analyzed oak samples, two generations of different ages were recognized and local chronologies were produced. The first one was dendrochronologically dated against the Southern Poland oak standard to the period 1796-1526 BC. This dating is in perfect agreement with the earlier produced result of radiocarbon analysis 3180+/-50 BP. The second chronology (4890+/-60 BP and 5000+/-40 BP) indicate that the oaks of that generation grown at the end of the Atlantic Period. Radiocarbon dating also enabled identification of trunks older than 5000 BP (5580+/-40 BP and 5330+/-40 BP), as well as of an age intermediate between these both chronologies (4370+/-50 BP). The analyses carried out indicate that the analyzed profiles contain mostly oak trunks from the Atlantic and Subboreal periods. They enable dating of the youngest part of the alluvial series to around 1500 BC.
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