Seismic geomorphology anomalies within a Pliocene deepwater channel complex in the Taranaki Basin, offshore New Zealand

2020 ◽  
pp. 1-27
Author(s):  
Julian Chenin ◽  
Clayton Silver ◽  
Heather Bedle

The Taranaki Basin, located offshore New Zealand, is a Cretaceous rift basin which has well defined yet complex Miocene deepwater sedimentary systems. This paper analyzes a pronounced anomalous seismic response in a late Miocene to early Pliocene deepwater channel within the 2005 Hector 3D survey located in the southern Taranaki Basin. Several seismic attributes were calculated to interpret the extent of these anomalous features. Modern analogues from Snedden (2013) within both the Iron River reservoir in Albania, Canada and the East Breaks Basin Four, offshore Gulf of Mexico suggest that these anomalous seismic features are most likely channel-body basal scours resulting from turbulent flows that eroded the base of the channel. One alternative interpretation is that this is not a channel but rather a scar left behind from a small-scale mass trasnport deposit (MTD) where sediment later ponded and filled in the rugose topography left by the MTD. This process has also been observed by Kremer et al. (2018) within the Molasse Basin in southern Germany. However, these scours could also be interpreted as pockmarks resulting from channel abandonment and fluid escape due to compaction. Jobe et al. (2011) described this process within submarine canyon systems, offshore Equatorial Guinea. Within all possible interpretations, there is evidence of differential compaction as sediment fills the accommodation space and creates a concave down expression immediately above the interpreted scours.

Author(s):  
J.G. Jago ◽  
M.W. Woolford

There is a growing shortage of labour within the dairy industry. To address this the industry needs to attract more people and/or reduce the labour requirements on dairy farms. Current milk harvesting techniques contribute to both the labour requirements and the current labour shortage within the industry as the process is labour-intensive and necessitates long and unsociable working hours. Automated milking systems (AMS) have been in operation, albeit on a small scale, on commercial farms in Europe for a decade and may have the potential to address labour issues within the New Zealand dairy industry. A research programme has been established (The Greenfield Project) which aims to determine the feasibility of automated milking under New Zealand dairying conditions. A Fullwoods MERLIN AMS has been installed on a protoype farmlet and is successfully milking a small herd of 41 cows. Progress from the prototype Greenfields system offers considerable potential for implementing AMS in extensive grazing systems. Keywords: automated milking systems, dairy cattle, grazing, labour


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Peter Higgins ◽  
Cooper A Grace ◽  
Soon A Lee ◽  
Matthew R Goddard

Abstract Saccharomyces cerevisiae is extensively utilized for commercial fermentation, and is also an important biological model; however, its ecology has only recently begun to be understood. Through the use of whole-genome sequencing, the species has been characterized into a number of distinct subpopulations, defined by geographical ranges and industrial uses. Here, the whole-genome sequences of 104 New Zealand (NZ) S. cerevisiae strains, including 52 novel genomes, are analyzed alongside 450 published sequences derived from various global locations. The impact of S. cerevisiae novel range expansion into NZ was investigated and these analyses reveal the positioning of NZ strains as a subgroup to the predominantly European/wine clade. A number of genomic differences with the European group correlate with range expansion into NZ, including 18 highly enriched single-nucleotide polymorphism (SNPs) and novel Ty1/2 insertions. While it is not possible to categorically determine if any genetic differences are due to stochastic process or the operations of natural selection, we suggest that the observation of NZ-specific copy number increases of four sugar transporter genes in the HXT family may reasonably represent an adaptation in the NZ S. cerevisiae subpopulation, and this correlates with the observations of copy number changes during adaptation in small-scale experimental evolution studies.


Symmetry ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 502 ◽  
Author(s):  
Jong-Hyun Kim ◽  
Wook Kim ◽  
Young Kim ◽  
Jung Lee

When we perform particle-based water simulation, water particles are often increased dramatically because of particle splitting around breaking holes to maintain the thin fluid sheets. Because most of the existing approaches do not consider the volume of the water particles, the water particles must have a very low mass to satisfy the law of the conservation of mass. This phenomenon smears the motion of the water, which would otherwise result in splashing, thereby resulting in artifacts such as numerical dissipation. Thus, we propose a new fluid-implicit, particle-based framework for maintaining and representing the thin sheets and turbulent flows of water. After splitting the water particles, the proposed method uses the ghost density and ghost mass to redistribute the difference in mass based on the volume of the water particles. Next, small-scale turbulent flows are formed in local regions and transferred in a smooth manner to the global flow field. Our results show us the turbulence details as well as the thin sheets of water, thereby obtaining an aesthetically pleasing improvement compared with existing methods.


1994 ◽  
Vol 47 (6S) ◽  
pp. S3-S13 ◽  
Author(s):  
Parviz Moin ◽  
Thomas Bewley

A brief review of current approaches to active feedback control of the fluctuations arising in turbulent flows is presented, emphasizing the mathematical techniques involved. Active feedback control schemes are categorized and compared by examining the extent to which they are based on the governing flow equations. These schemes are broken down into the following categories: adaptive schemes, schemes based on heuristic physical arguments, schemes based on a dynamical systems approach, and schemes based on optimal control theory applied directly to the Navier-Stokes equations. Recent advances in methods of implementing small scale flow control ideas are also reviewed.


2021 ◽  
Author(s):  
Kevin Michael Torres ◽  
Noura Al Madani ◽  
Rodrigo Rafael Gutierrez

Abstract The study presents the sequence stratigraphy of the carbonate platform focused in lower part of Shuaiba Formation, as well as the organization of the arrangement formed by the cyclical sedimentological evolution at high-resolution scale, through the facies analysis, diagenetical imprints and finally, significance of stable carbonate isotope results in the building up of carbonate platform in southeast Abu Dhabi. Interpreted stratigraphic surfaces from integration of depositional facies reviewed in all available cored data within studied area and stable carbon isotope results allowed that four small-scale regression-transgression depositional cycles can be discriminated which are stacked into a medium-scale sequence, that may record a 600 kyr Milankovitch signal. The small-scale sequences were correlated within the studied area using both conventional well logs and stable isotope records. Transgression hemicycles represent the increasing of accommodation space and can be identified in direct evidence, such as 25-40 ft. thickness of lithocodium/bacinella floatstones and skeletal peloidal packstones facies, association of facies interpreted within upper slope sub-environment. Likewise, in δ13C profiles, the rise/fall turnarounds of small-scale sequences are marked by negative δ13C peaks and associated with characteristics patterns: (1) proportion decrease of shallower sub-environments facies is interpreted as an rising relative sea-level and (2) decreasing δ13C trends interpreted to be related to decreasing nutrient supply. The medium/big pores of floatstones poorly connected in packstone matrix are expressed in the medium/high porosity with low permeabilities. In contrast, regressive hemicycles represent the reduction in accommodation space and can be characterized in direct evidence, such as the growing up of persistent 10-20 ft. thickness with thousands of meters of correlation of stromatoporoids and rudist facies, association of facies interpreted within shelf-margin complex sub-environment. In addition, the fall/rise turnarounds are marked by positive δ13C peaks, associated with the stromatoporoids/rudists mounds with characteristic patterns: (1) proportion increase of shallower sub-environments facies is interpreted as falling relative sea-level and increase in proximity and (2) increasing δ13C values interpreted to reflect increasing nutrient supply. Unusually very high permeability is attributed to the present of fractures and dissolution events that is enhanced where proportion of stromatoporoids facies are more pronounced. The described characterization resulted in the identification of genetic cycles that reproduce the sedimentological evolution, which are presented in small-scale sequences. In addition, the δ13C values enabled to understand the internal organization and the development of the carbonate building up in the Shuaiba shallow platform evolution. This study provides update and understanding on sedimentary facies, depositional pattern, and expands on previous published works, using new approach from semi-regional to local scales. Finally, results help to understand the laterally extensive water break-through thin intervals, which are directly related to the regressive hemicycles described previously.


2018 ◽  
Vol 857 ◽  
pp. 270-290 ◽  
Author(s):  
Josef Hasslberger ◽  
Markus Klein ◽  
Nilanjan Chakraborty

This paper presents a detailed investigation of flow topologies in bubble-induced two-phase turbulence. Two freely moving and deforming air bubbles that have been suspended in liquid water under counterflow conditions have been considered for this analysis. The direct numerical simulation data considered here are based on the one-fluid formulation of the two-phase flow governing equations. To study the development of coherent structures, a local flow topology analysis is performed. Using the invariants of the velocity gradient tensor, all possible small-scale flow structures can be categorized into two nodal and two focal topologies for incompressible turbulent flows. The volume fraction of focal topologies in the gaseous phase is consistently higher than in the surrounding liquid phase. This observation has been argued to be linked to a strong vorticity production at the regions of simultaneous high fluid velocity and high interface curvature. Depending on the regime (steady/laminar or unsteady/turbulent), additional effects related to the density and viscosity jump at the interface influence the behaviour. The analysis also points to a specific term of the vorticity transport equation as being responsible for the induction of vortical motion at the interface. Besides the known mechanisms, this term, related to surface tension and gradients of interface curvature, represents another potential source of turbulence production that lends itself to further investigation.


2005 ◽  
Vol 51 (12) ◽  
pp. 191-199 ◽  
Author(s):  
R. Craggs ◽  
L. Golding ◽  
S. Clearwater ◽  
L. Susarla ◽  
W. Donovan

Chironomid midge larvae are a valuable component of wastewater stabilisation pond (WSP) ecology. However, in high numbers, adult midge swarms can be a nuisance to near-by urban areas. Improving WSP treatment by incorporating aerobic or maturation ponds or by the addition of pre-treatment to reduce organic loading also increases the availability of aerobic sediment (midge larva habitat) in the pond system and the potential for midge nuisance problems. The efficacy of Maldison, an organophosphate traditionally used to control midge larvae in New Zealand WSPs, was compared to Bacillus thuringiensis var. israelensis (Bti), Methoprene, Pyriproxyfen and Diflubenzuron which are all more specific to insects and have fewer adverse environmental effects. Initial laboratory trials established the concentration of each compound required to achieve 95% control of the midge population. During 21-day small-scale trials within the WSP, Bti, Diflubenzuron and Maldison reduced live larvae numbers substantially (80–89%) compared to controls and adult midge emergence was markedly reduced by all compounds (72–96%). Large-scale trials with Bti (Vectobac® WG) powder (1000 μg/L) only caused a slight reduction in midge larvae numbers compared to controls and had little effect on adult emergence, however, Methoprene (Prolink XRG granules) (50 μgAI/L) reduced midge adult emergence by ∼80% over 25 days and has been used successfully to control several midge nuisance outbreaks.


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