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Petrographical and geochemical changes in Bosnian stalagmites and their palaeo-environmental significance
Full text linkDetailed petrographic observations have been coupled with trace element and δ13C - δ18O
analyses in order to investigate their dynamics in two Holocene Bosnian speleothems. The
potential of this multiproxy approach in providing a means to extract palaeo-environmental
information from stalagmites whose stable isotope signals are noisy and without obvious trends
has been tested. The studied stalagmites are mostly characterized by columnar microcrystalline
fabric. At the sub-millimetre scale of lamination, different microcrystalline columnar sub-types
(open and closed) have been detected and classified on the basis of the observed porosity
and the crystallite size. The presence of variations in crystallite arrangement at the lamina
scale suggests the occurrence of small-scale environmental changes recorded in the studied
samples. A positive correlation was found found between Mg concentration, δ13C and fabric
variations, while a negative correlation relates those parameters with Sr concentration. Both
δ13C and fabric changes appear to be directly related to changes in hydrology. The detailed
observation of calcite fabrics combined with stable isotope and trace element profiles allowed
for the interpretation of the conditions under which the speleothems were deposited
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
KAKO SPELEOLOGIJA MOŽE DOPRINIJETI POZNAVANJU KRŠKIH VODONOSNIKA? PRIMJER IZ PEĆINE GOVJEŠTICA
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