5 research outputs found
Structural heterogeneity of the midcrust adjacent to the central Alpine Fault, New Zealand: Inferences from seismic tomography and seismicity between Harihari and Ross
© 2015. American Geophysical Union. All Rights Reserved. Determining the rates and distributions of microseismicity near major faults at different points in the seismic cycle is a crucial step toward understanding plate boundary seismogenesis. We analyze data from temporary seismic arrays spanning the central section of the Alpine Fault, New Zealand, using double-difference seismic tomography. This portion of the fault last ruptured in a large earthquake in 1717 AD and is now late in its typical 330 year cycle of Mw∼8 earthquakes. Seismicity varies systematically with distance from the Alpine Fault: (1) directly beneath the fault trace, earthquakes are sparse and largely confined to the footwall at depths of 4-11 km; (2) at distances of 0-9 km southeast of the trace, seismicity is similarly sparse and shallower than 8 km; (3) at distances of 9-20 km southeast of the fault trace, earthquakes are much more prevalent and shallower than 7 km. Hypocenter lineations here are subparallel to faults mapped near the Main Divide of the Southern Alps, confirming that those faults are active. The region of enhanced seismicity is associated with the highest topography and a high-velocity tongue doming at 3-5 km depth. The low-seismicity zone adjacent to the Alpine Fault trace is associated with Vp and Vs values at midcrustal depths about 8 and 6% lower than further southeast. We interpret lateral variations in seismicity rate to reflect patterns of horizontal strain rate superimposed on heterogeneous crustal structure, and the variations in seismicity cutoff depth to be controlled by temperature and permeability structure variations. Key Points: Seismicity is sparse near the Alpine Fault late in its typical seismic cycle Seismicity rates increase abruptly 9 km southeast of the fault trace This transition coincides with a strain rate peak and lateral velocity gradient
Innovating a consumer awareness of sweet potato: Industry, research and consumer adoption issues
Australian sweetpotato production has grown remarkably (1700%) in the last16 years. Growers currently market 75 000 t per annum, worth $80-90 million at farm gate. Gold-fleshed dessert types dominate (90% of total production), almost exclusively cv. Beauregard, bred at Louisiana State University Agricultural Center (LSU AgCenter) in the USA. Australian sweetpotato growers desire alternative cultivars, to reduce risks associated with relying on one genotype. They also wish to expand demand, by offering diverse products. Recent research identified Evangeline, another LSU AgCenter cultivar, as an alternate gold sweetpotato possessing attributes desired by consumers (regular, smooth shape; highly coloured skin and flesh). In experimental and grower evaluations across key Australian growing regions in Queensland and New South Wales, Evangeline produced marketable yields similar to Beauregard. Evangeline had a high proportion of premium small-medium sweetpotatoes. In sandy locations, Evangeline also demonstrated superior root-knot nematode resistance to Beauregard. However, compared to Beauregard, Evangeline had greater risks of splitting, or over-purple skin colouration, at harvest, particularly when dug in Winter/Spring. Initial evidence suggested splitting was more common with increased fertiliser nitrogen inputs. Split roots or off-specification colours are unmarketable; the associated risks are currently substantial impediments to adoption of Evangeline by Australian sweetpotato growers. Scientists from Agri-Science Queensland and Central Queensland University are currently partnering with Australian Sweetpotato Growers (Inc.) to develop strategies for maximising performance and mitigating risks of growing Evangeline in Australian conditions.This will enhance industry profitability and resilience; improve understanding of sweetpotato physiology; and increase diversity and quality of sweetpotato products available to consumers
Innovating a new cultivar in partnership with the Australian sweetpotato industry: agronomic adaptation issues
Australian sweetpotato production has grown remarkably (1700%) in the last 16 years. Growers currently market 75000 t per annum, worth $80-90 million at farm gate. Gold-fleshed dessert types dominate (90% of total production), almost exclusively cultivar 'Beauregard', bred at Louisiana State University Agricultural Center (LSU AgCenter) in the USA. Australian sweetpotato growers desire alternative cultivars, to reduce risks associated with relying on one genotype. They also wish to expand demand, by offering diverse products. Recent research identified 'Evangeline', another LSU AgCenter cultivar, as an alternate gold sweetpotato possessing attributes desired by consumers (regular, smooth shape; highly coloured skin and flesh). In experimental and grower evaluations across key Australian growing regions in Queensland and New South Wales, 'Evangeline' produced marketable yields similar to 'Beauregard'. 'Evangeline' had a high proportion of premium small-medium sweetpotatoes. In sandy locations, 'Evangeline' also demonstrated superior root-knot nematode resistance to 'Beauregard'. However, compared to 'Beauregard', 'Evangeline' had greater risks of splitting, or over-purple skin colouration, at harvest, particularly when dug in Winter/Spring. Initial evidence suggested splitting was more common with increased fertiliser nitrogen inputs. Split roots or off-specification colours are unmarketable; the associated risks are currently substantial impediments to adoption of 'Evangeline' by Australian sweetpotato growers. Scientists from Agri-Science Queensland and Central Queensland University are currently partnering with Australian Sweetpotato Growers (Inc.) to develop strategies for maximising performance and mitigating risks of growing 'Evangeline' in Australian conditions. This will enhance industry profitability and resilience; improve understanding of sweetpotato physiology; and increase diversity and quality of sweetpotato products available to consumers
Centrality dependence of charged hadron transverse momentum spectra in Au + Au collisions from square root of s(NN)=62.4 to 200 GeV
We have measured transverse momentum distributions of charged hadrons produced in Au + Au collisions at square root s(NN) = 62.4 GeV. The spectra are presented for transverse momenta 0.2
Energy dependence of elliptic flow over a large pseudorapidity range in Au + Au collisions at the BNL relativistic heavy ion collider
This Letter describes the measurement of the energy dependence of elliptic flow for charged particles in Au+Au collisions using the PHOBOS detector at the Relativistic Heavy Ion Collider. Data taken at collision energies of root s(NN) = 19.6, 62.4, 130, and 200 GeV are shown over a wide range in pseudorapidity. These results, when plotted as a function of eta' = vertical bar eta vertical bar - y(beam), scale with approximate linearity throughout eta('), implying no sharp changes in the dynamics of particle production as a function of pseudorapidity or increasing beam energy