Wokół zagadnień trwałej ochrony zasobów cyfrowych

Słowo wstępne: "Cyfrowe kolekcje wartościowych dokumentów powstają w wyniku procesów elektronicznego publikowania oraz digitalizacji materiałów analogowych. Są one świadectwem dorobku polskiej działalności naukowej i kulturowej. Digitalizacja upowszechnia się w instytucjach pamięci jako forma zabezpieczenia zagrożonych zniszczeniem oryginalnych materiałów. Oficyny wydawnicze coraz częściej publikują treści naukowe w cyfrowej postaci, rezygnując z wersji drukowanych. Instytuty naukowe i badawcze oraz uczelnie wyższe tworzą instytucjonalne repozytoria, pozwalające na szybkie i samodzielne udostępnianie publiczności wyników prowadzonych prac badawczych. Powstające w ten sposób cyfrowe zasoby współtworzą światowe dziedzictwo. Podlegają one trwałej ochronie z myślą o potrzebach obecnych i przyszłych użytkowników."(...

CASPAR – długoterminowa archiwizacja obiektów cyfrowych

[CASPAR – long-term preservation of digital objects Streszczenie]In the paper authors will present an international research project CASPAR – Cultural, Artistic and Scientific knowledge for Preservation, Access and Retrieval, devoted to writing, sharing and searching for information on science, art and culture. Authors will discuss the goals, objectives, architecture and functionality of the system CASPAR

14C Dating of Calcareous Tufa from Different Environments

From the 12th International Radiocarbon Conference held in Trondheim, June 24-28, 1985.14C dates of carbonate and organic matter fractions are compared with a series of calcareous tufa samples from selected sites representing different geochemical environments and associated with different bedrocks. Results obtained in this study indicate values of apparent age ranging from 940 +/- 110 yr for calcareous tufas associated with Pleistocene sediments to 2000 +/- 110 yr and even ca 4000 yr for tufas from sites associated with Jurassic or Cretaceous limestone. It was found also that within each of the investigated sites the value of apparent age does not change significantly with the age of the tufa layer.This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Further Investigations on 14C Dating of Calcareous Tufa

Systematic studies on 14C dating of tufa profiles in southern Poland have resulted in developing a simple phenomenological model which enables us to estimate the reservoir correction factor of 14C dates of individual carbonate samples. We made further studies to test model assumptions and to verify relationships between the value of reservoir correction factor TR and 13C content of tufa carbonate. Two new study sites, Rudawa and Szklarka, are close to previously studied sites. Four tufa samples with associated organic fraction from ca 2000m asl in South America (Peruvian Andes) were measured to test the possible application of the developed model to tufas in different geochemical and climatic environments. Finally, a series of calcareous tufa samples from the Villers-devant-Orval profile (Belgium) were dated, although no direct comparison with organic matter dates is available for this profile.This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Mieczysław F. Pazdur, 1946–1995

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

The Relations Between Carbon Isotope Composition and Apparent Age of Freshwater Tufaceous Sediments

This paper presents a synthetic approach to 14C dating of calcareous tufa, based on statistical analysis of correlations betwen lithologic type of tufaceous sediment, carbon isotope composition, and apparent age. Experimental data on several profiles from southern Poland and the United Kingdom reveal either constant or systematically changing values of apparent age. Constant value of apparent age in a profile can be attributed to calcareous muds precipitated from stagnant or low-energy water, and to tufas precipitated from turbulent water (oncoids, stromatolites, moss travertines) which are characterized by lack of significant correlation between delta-13C and 14C age of tufa carbonate. It was found that the relation between the apparent age of tufaceous sediment and delta-13C value of tufa carbonate depends on lithologic type of tufa. Phenomenological equations describing the dependence of apparent age upon delta-13C are given, and applied to estimate true ages of tufas from Gliczarow (southern Poland) and Folkestone (United Kingdom).This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Gliwice Radiocarbon Dates V

This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Radiocarbon Dating of Holocene Calcareous Tufa in Southern Poland

Calcareous tufa from five sites in southern Poland, representing several most typical conditions of tufa sedimentation, were chosen for 14C, 13C, and 18O measurements. These tufas were deposited in a high-energy turbulent stream (the Raerawka site), in streams with moderate but variable flow (Rzerzusnia and Trzebienice), and in semilimnic conditions (Sieradowice site). Sediments of the Gliczarow site represent spring travertines. In all but the latter site, direct comparison of 14C dates of carbonate and organic fractions was possible, leading to an estimate of initial apparent age of carbonate sediments. Clear correlation was found between the value of initial apparent age of tufas and the hydrodynamic conditions of sedimentation. Corresponding values range from ca 3900 yr (Raetawka) to 910 yr for semilimnic sediments (Sieradowice). Intermediate, almost identical values, equal to 2460 +/- 200 yr and 2100 +/- 160 yr, were obtained for tufas from Rzerzusnia and Trzebienice, respectively. Detailed sedimentologic classification of tufaceous deposits is presented and some primary and secondary factors affecting the accuracy of radiocarbon dates of various types of tufas are also discussed.This material was digitized as part of a cooperative project between Radiocarbon and the University of Arizona Libraries.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202