Recognition of micro-scale deformation structures in glacial sediments - pattern perception, observer bias and the influence of experience

It is a scientist's mission to try to remain unbiased. However, certain factors play a role in scientific analyses that are not controlled by conscious thought. These factors are potentially very important in areas of science where interpretations are based on a scientist's ability to identify patterns or structures. One such area is the micromorphology of glacial sediments. In this paper we investigate the role of an analyst's experience in relation to pattern perception with specific reference to turbate microstructures in glacial diamictons. An experiment was conducted on 52 participants, which demonstrated that, as may be expected, more experienced (glacial) micromorphologists tend to exhibit a higher sensitivity-to-signal, but that complete novices, if given clear instructions, can reach levels of sensitivity similar to those of experts. It also showed, perhaps more surprisingly, that response bias does not decrease with experience. We discuss psychological factors, such as the drive for success and consistency, that may have contributed to these results and investigate their possible implications in the micromorphological analysis and interpretation of glacial sediments

A Foraminiferal study of Cuban mangrove sediments

The importance of mangrove environments is becoming increasingly apparent as more and more research is done in the area. This study attempts to identify zonation trends and patterns within the foraminiferal assemblages found across a range of micro-habitats within the mangrove ecosystem. This is so as to identify a set of parameters found in the sedimentary record that may enable the monitoring of environmental characteristics within modern mangroves by sedimentary analysis but also so as to look at the possibility of using fossil foraminifera to identify palaeo-mangrove locations. Both possibilities would increase the accuracy of mapping and modelling mangrove environments. The study found that while there may be a dominant environmental parameter causing assemblage diversity across a system there are other environmental factors that although not appearing to fit typical trend data have a recordable affect on certain species within these assemblages. This means that with increased resolution studies and statistical analysis it may be possible to identify key trends in species that could be used to monitor the diversity and health of mangrove environments. The study also found that the greatest amount of variability at individual locations is exhibited mainly in the macro foraminiferal (>300um) assemblages below this size fraction the environmental parameters appear to have a lesser effect on the diversity of the sample and other statistical analysis parameters. This leads too two conclusions, that using the larger foraminiferal sizes in ecological studies has the advantage of making the taxa easier to identify and clearly showing any trends in diversity across the system that would have been deemed negligible had the entirety of the sediment been examined. However it also leads to the conclusion that previous studies that have focussed upon the macroforaminiferal size fractions may have exhibited lower diversity or higher degrees of change than those actually representative of the location being studied as a whole.Faculty of Scienc