Journal Articles

Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915

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Start date: 1990End date: 1999

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Now showing 1 - 7 of 7
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    Dairy deregulation and low-input dairy production: A bioeconomic evaluation
    (Western Agricultural Economics Association, 1999) Tozer PR; Huffaker RG
    Deregulation of the Australian dairy industry could affect the utilization of resources by milk producers and the profitability of dairy production. In this study we examine the feed mix that dairy producers use, both pastures and supplements, under partial and total deregulation. We are particularly interested in the interaction of pasture utilization and farm profitability. The results of this research demonstrate that profitable low-input dairying is constrained by the most limiting resource, feed supplied by pasture, and that the interactions between economic and biological processes are critical to farm profitability.
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    Large hydrovolcanic field in the Pannonian Basin: general characteristics of the Bakony- Balaton Highland Volcanic Field, Hungary.
    (Massey University., 1999-01-01) Nemeth, Karoly; Martin, Ulrike
    No abstract available
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    Eroded porous-media aquifer controlled hydrovolcanic centers in the South Lake Balaton region, Hungary: The Boglar volcano
    (Akad�miai Kiad�, 1999) Nemeth K; Martin U; Philippe M
    The volcanic centers next to Balatonboglar township represent 3.5 Ma old products of post-extensional alkaline basaltic volcanism in the Pannonian Basin (eastern Central Europe). They are small, eroded volcanic centers located on the southern shore of Lake Balaton and genetically related to the Bakony-Balaton Highland Volcanic Field eruptive centers. The relatively small area (500 m x 500 m) contains at least 2 eruptive centers, which are probably related to each other and have built up a complex volcano, called the Boglar Volcano. The volcanic rocks overlie the older Pannonian clastic sedimentary sequence and represent the topographic highs in this area. The areas of lower elevation around the eruptive centers are covered by Pleistocene to Holocene swamp, lake and river clastic sediments, which strongly suggest intense erosion during the last few million years. All volcanic rocks around Balatonboglar are volcaniclastic. There is no evidence of lava flow occurrence. The volcaniclastic sediments have been divided into two lithofacies associations. The largest amount of volcaniclastic rocks is located in the center of the local hills and has been interpreted as a phreatomagmatic crater fill lapilli tuff. They contain large amphibole megacrysts and small olivine crystals. The second lithofacies association is interpreted as lahar deposits. This sequence contains an unusually large amount of fossil tree trunks, which are identified as Abies species. Within a small area in the western hills small outcrops show evidence of maar-lake clastic sediment occurrence. On the hilltops debris shows intimate interaction processes between clastic sediments and basaltic melt. We interpret this to mean that the eruptive centers of Boglar Volcano were formed under subaerial conditions, with explosions fueled by intensive interaction between water-saturated Pannonian sand and uprising basaltic magma.
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    Late miocene paleo-geomorphology of the bakony-balaton highland volcanic field (Hungary) using physical volcanology data
    (Gebruder Borntraeger, 1999) Nemeth K; Martin U
    A new view is presented of the Bakony-Balaton Highland Volcanic Field (BBHVF), Hungary, active in late Miocene and built up of ca. 100 mostly alkaline basaltic eruptive centers, scoria cones, tuff rings, maar volcanic complexes and shield volcanoes. A detailed map shows the physical volcanology of the monogenetic volcanic field. In areas where thick Pannonian Sandstone beds build up the pre-volcanic strata normal maar volcanic centers have formed with usually thick late magmatic infill in the maar basins. In areas, where relatively thin Pannonian Sandstone beds resting on thick Mesozoic or Paleozoic fracture-controlled, karstwater-bearing aquifer, large unusual maar volcanic sequences appear (Tihany type maar volcanoes). In the northern part of the field large former scoria cones and shield volcanoes give evidence for a smaller impact of the ground and surface water causing phreatomagmatic explosive activity. The Tihany type maar volcanic centers are usually filled by thick maar lake deposits, building up Gilbert type gravelly, scoria rich deltas in the northern side of the maar basins, suggesting a mostly north to south fluvial system in the pre-volcanic surface. Calculating paleosurface elevation for the eruptive centers, two paleo-geomorphology maps are drawn for a younger (4-2.8 Ma) and an older (7.54-4 Ma) scenario. The erosion rate of the volcanic field is estimated to vary between 96 m/Ma and 18 m/Ma. In the western site of BBHVF the erosion rate is higher (more than 60 m/Ma, Tapolca Basin), and an average 50 m/Ma in the center and eastern side.
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    Subaqueous volcanism and their depositional processes, their relationship to subaerial volcanism: review
    (Massey University., 1999-01-01) Nemeth, Karoly
    A vizalatti vulkanizmus jelenségei és üledékképződési folyamatai, kapcsolatai a szárazföldi vulkáni folyamatokkal: attekintes (Subaqueous volcanism and their depositional processes, their relationship to subaerial volcanism: review)
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    The Supervisor
    (World Scientific Publishing, 1/01/1997) Sligo F
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