Discriminating intra-parasequence stratigraphic units from two-dimensional quantitative parameters

ABSTRACT The intra-parasequence scale is still relatively unexplored territory in high-resolution sequence stratigraphy. The analysis of internal genetic units of parasequences has commonly been simplified to the definition of bedsets. Such simplification is insufficient to cover the complexity involved in the building of individual parasequences. Different types of intra-parasequence units have been previously identified and characterized in successive wave-dominated shoreface–shelf parasequences in the Lower Cretaceous Pilmatué Member of the Agrio Formation in central Neuquén Basin. Sedimentary and stratigraphic attributes such as the number of intra-parasequence units, their thickness, the proportions of facies associations in the regressive interval, the lateral extent of bounding surfaces, the degree of deepening recorded across these boundaries, and the type and lateral extent of associated transgressive deposits are quantitatively analyzed in this paper. Based on the analysis of these quantified attributes, three different scales of genetic units in parasequences are identified. 1) Bedset complexes are 10–40 m thick, basin to upper-shoreface successions, bounded by 5 to 16 km-long surfaces with a degree of deepening of one to three facies belts. These stratigraphic units represent the highest hierarchy of intra-parasequence stratigraphic units, and the vertical stacking of two or three of them typically forms an individual parasequence. 2) Bedsets are 2–20 m thick, offshore to upper-shoreface successions, bounded by up to 10 km long surfaces with a degree of deepening of zero to one facies belt. Two or three bedsets stack vertically build a bedset complex. 3) Sub-bedsets are 0.5–5 m thick, offshore transition to upper-shoreface successions, bounded by 0.5 to 2 km long surfaces with a degree of deepening of zero to one facies belt. Two or three sub-bedsets commonly stack to form bedsets. The proposed methodology indicates that the combination of thickness with the proportion of facies associations in the regressive interval of stratigraphic units can be used to discriminate between bedsets and sub-bedsets, whereas for higher ranks (bedsets and bedset complexes) the degree of deepening, lateral extent of bounding surfaces, and the characteristics of associated shell-bed deposits become more effective. Finally, the results for the Pilmatué Member are compared with other ancient and Holocene examples to improve understanding of the high-frequency evolution of wave-dominated shoreface–shelf systems.

The philosophies of science in developing nursing science

During the successive wave of globalization, nurses emphasized the requirement of specialized knowledge to improve the nursing as a profession and to make the transition from vocation to profession. The science of nursing is a foundation of knowing for nurses. Also there has a shift of nursing metaparadigm based on Kuhn’s philosophy of science. It was assumed that Philosophies are theoretical works that included one or more of the metaparadigm concepts. Philosophy provide us broad general view of what is science and human science, evolution of science, function of scientific theory, scientific methodologies, different philosophical approaches, significant philosophical shift in different eras and it would be helpful for the development of nursing as a discipline from adhering to the knowledge that we learnt in this paper.

The philosophies of science in developing nursing science

During the successive wave of globalization, nurses emphasized the requirement of specialized knowledge to improve the nursing as a profession and to make the transition from vocation to profession. The science of nursing is a foundation of knowing for nurses. Also there has a shift of nursing metaparadigm based on Kuhn’s philosophy of science. It was assumed that Philosophies are theoretical works that included one or more of the metaparadigm concepts. Philosophy provide us broad general view of what is science and human science, evolution of science, function of scientific theory, scientific methodologies, different philosophical approaches, significant philosophical shift in different eras and it would be helpful for the development of nursing as a discipline from adhering to the knowledge that we learnt in this paper.

STRATEGIES OF THE UNEMPLOYED IN SOUTH AFRICA: DOES MOVING ALLOW THE UNEMPLOYED TO GET AHEAD?

This paper examines the survival strategies of the unemployed using the balanced panel of the first three waves of the National Income Dynamics Study. We find that in response to unemployment and almost no unemployment insurance, unemployed individuals look to parents, relatives and friends for economic support. They are more likely to attach themselves to household that have some income through an employed member or in receive of state support. In many cases the unemployed delay setting up their own households while others move back into family households when faced with persistent unemployment. We use a probit model to show that the unemployed who move are more likely to be employed in a successive wave. The effect of moving on employment status remains significant and positive when we take into account household and individual characteristics. Moving allows the unemployed to get ahead.Â

Wave-in-Deck Forces on Fixed Horizontal Decks of Offshore Platforms

The problem of wave-in-deck loading on offshore structures involves complex physical mechanisms which require close study. In this paper, the wave-in-deck forces generated on the bottom plate of a rigidly mounted, box-shaped structure subjected to unidirectional regular waves are quantified by means of two approaches. The first is an analytical momentum approach recommended by classification societies and the second is a computational fluid dynamics (CFD) approach based on the volume of fluid (VOF) method implemented in the commercial code FLUENT. The change in force due to very small variations in wave steepness and air gap is investigated and discussed. Several numerical trials are conducted to optimise the computational domain and model discretisation suggestions are made. The numerical results are compared with physical model tests recently carried out at the Australian Maritime College (AMC). The results of the successive wave impacts are analysed using a discrete wavelet tool to ensure that the temporal information of slamming events is not lost in signal analysis and filtering. By comparing the theoretical and experimental results it was found that in many cases the momentum method underestimates the magnitude of the horizontal and upward directed wave-in-deck forces. Although the three-dimensional CFD cases tested are noticeably time-consuming, these simulations were found to be in good agreement with the experimental measurements.