Academic literature on the topic 'Woodbury granites'

The northeast Thelon Basin in the Kivalliq region of Nunavut is prospective for uranium deposits. Recently discovered basement-hosted, unconformity-associated prospects west of Kiggavik are restricted to deformed and metamorphosed Neoarchean psammitic enclaves of the Woodburn Lake group within 1.83 Ga Hudson granite and Martell syenite that together comprise the Shultz Lake intrusive complex (SLIC). The depth and geometry of the intrusive complex are relatively unknown as the geological constraints are poor; the drilling is sparse and of shallow depth extent as it was not targeting the basement but shallower multiply faulted and highly altered demagnetized zones. This study aims to constrain the geometry and context of the Shultz Lake intrusive complex with respect to the ore-hosting Neoarchean metasedimentary rocks and intersecting reactivated fault arrays through geophysical modelling of detailed aeromagnetic and gravity data integrated with new geological knowledge. By integrating detailed gravity, aeromagnetic, and structural geology observations measured along a series of transects with a petrophysical rock properties database, it is possible to derive constraints on the depth and thickness (200–300 m) of the SLIC. Quantitative comparison and integration of multiple hypothetical geometries favours a model wherein the SLIC, together with metasedimentary and older basement gneiss, has been structurally emplaced over the Neoarchean metasediments.

The implementation gap between science, policy and practice has led to loss of biodiversity and ecosystem services throughout Africa and is described in a case study from Limpopo Province, South Africa. In 2006, the South African National Biodiversity Institute first highlighted the Woodbush Granite Grassland (WGG) in the Greater Tzaneen Local Municipality as the only Critically Endangered ecosystem in Limpopo Province. Five years later (2011), the Critically Endangered listing was published in the Government Gazette No. 34809. After repeated and sustained efforts for many years from volunteers of a local environmental group – currently known as the Friends of the Haenertsburg Grassland (FroHG) – in 2015 the intent to formally protect 126 ha was published in the Government Gazette No. 2609. Unfortunately, the proposed protected area accounts for only 66% of the largest remaining fragment of WGG, which excludes an important colony of medicinal plants. Considering that only 6% of the original extent of WGG remains in an untransformed state the whole fragment should be conserved. Non-alignment of municipal spatial priorities, as in the Haenertsburg town plan from 1896, to provincial and national environmental priorities has resulted in numerous incidents that have degraded what little remains of the WGG ecosystem. Failure of the provincial authorities to act timeously to enforce environmental regulations resulted in the FroHG successfully involving national authorities to stop illegal land occupation while another incident involving an illegal fence was resolved 9 years after erection. A strengthened relationship with Lepelle Northern Water has resulted in better planning of activities in relation to an existing pipeline. This case study shows various avenues available to environmental volunteer groups in South Africa and suggests that long-term lobbying can yield positive results.Conservation implications: Formal conservation of WGG through the intended nature reserve proclamation represents application of environmental legislation (notably Listing Notice 3, National Environmental Management Act 107 of 1998: Environmental Impact Assessment Regulations, 2014), scientific recommendations and policy. Better cooperation between provincial administration and FroHG will benefit the protection and management of WGG.

Thesis (M. Sc. (Botany)) -- University of Limpopo, 2019
The Woodbush Granite Grassland (WGG) is the most threatened vegetation type in Limpopo Province of South Africa. However, it has a high conservation value, because few examples of this vegetation type remain in southern Africa. Unfortunately, a large part of it is not formally conserved, making this the vegetation type most urgently in need of conservation. The study aimed at mapping transformation of the WGG, identifying species of conservation importance, and providing a management plan required for maintenance of the WGG. The objectives of the study included compiling a transformation map for the WGG, which also involved describing the remaining patches of the WGG that are in a natural or near-natural state. It also provides information on species of conservation importance, medicinal plants and threats to the WGG. On the four main study sites (Iron Crown Grassland, Haenertsburg Grassland, Ebenezer Dam Nature Reserve Grassland, and Ebenezer Dam Perimeter Grassland), quadratic plots were randomly set with a size of 25 x 25 m, and subplots of 1 x 1 m. Vegetation mapping was done during summer and winter. At each plot data was collected on all plant species occurring within the quadrat. A cover score was assigned to each plant species. A modified Braun-Blanquet data collection sheet was employed to obtain baseline data. For transformation mapping GeoTerra Image (GTI), land cover data were extracted for the WGG, using the modelled boundary as a mask, with 5 categories of transformation defined. Of the surveyed sites, the Ebenezer Dam Nature Reserve Grassland has the highest number of species, while the Haenertsburg Grassland contained the most endemic species of conservation importance. Rare species such as the Aloe zebrina, which does not occur in any formally protected area, and medicinal plants such as Athrixia phylicoides, occur on the WGG. All sites have importance with regard to WGG conservation. Identified threats include the spread of alien invasive plants, uncontrolled collection of medicinal plants, urban development, and poorly timed anthropogenic fire. vi The WGG underwent transformation to other land classes. Grassland clearing for plantations and cultivation were the main causal factors behind the observed WGG losses, with a total of 55.25% transformed. Transformation by afforestation is considered irreversible. It is concluded that the WGG is of conservation importance, and that some of it has been transformed to exotic timber plantations. The grassland is under various threats; therefore it is recommended that: (1) The proposed management plan provided in this study be adopted, (2) further research on the WGG be done on medicinal plants, (3) phytosociological and floristic studies be conducted and, (4) the effects of fire and alien invasive plant species on the grassland be investigated.