The Waipara – Kowai groundwater allocation zones (referred to as zones) are located 50 kilometers north of Christchurch. Land use in the Waipara zone has evolved from dry land farming towards horticultural and irrigated pastoral farming, and as such the demand for groundwater resources has increased significantly. Recent 14C age dating has shown that deep wells tap >1000 years old water, raising concerns about possible resource mining. The Kowai groundwater allocation zone has had minimal regional hydrogeological investigations and previously little is known about the groundwater resources here. The Waipara – Kowai groundwater allocation zones are located near obliquely convergent plate margin and the Porters Pass Fault System. Recent (early Quaternary) deformation has been noted by workers along margins and associated with emerging structures within basins. These emerging faults and folds within the basin are acting as hydrological barriers, hindering the passage of groundwater within the basin. A geomorphic map was constructed for this study based on existing soils maps, limited field soil surveys and morphometric analysis. Nine geomorphic surfaces are described, with inferred ages of modern to >73 ka. The geomorphic investigation revealed that the Kowai groundwater allocation zone surface is stepped, with increasing thickness of loess up gradient on the downlands. Near the coast there is intercalated terrestrial and marine sediments, to the west overlying the Kowai Formation are small alluvial fans. In the Waipara Basin the Waipara fan dominates the central portion of the basin, with smaller fluvial and alluvial fans building out from the margins. Groundwater recharge was investigated using chemical, isotopic, water level observations and a simple water balance. It was found that in the Kowai zone the major recharge sources were the rainfall, losses from the rivers and streams. The southern region of the Waipara zone is recharged by rainfall with small contributions from the Kowai River (North Branch). In the South region of the Waipara Basin groundwater recharge is derived from rainfall and losses from streams. The groundwater systems are conceptualized as being topographically driven, with slope – basin floors interactions being an important source of groundwater recharge.

The Waipara – Kowai groundwater allocation zones (referred to as zones) are located 50 kilometers north of Christchurch. Land use in the Waipara zone has evolved from dry land farming towards horticultural and irrigated pastoral farming, and as such the demand for groundwater resources has increased significantly. Recent 14C age dating has shown that deep wells tap >1000 years old water, raising concerns about possible resource mining. The Kowai groundwater allocation zone has had minimal regional hydrogeological investigations and previously little is known about the groundwater resources here. The Waipara – Kowai groundwater allocation zones are located near obliquely convergent plate margin and the Porters Pass Fault System. Recent (early Quaternary) deformation has been noted by workers along margins and associated with emerging structures within basins. These emerging faults and folds within the basin are acting as hydrological barriers, hindering the passage of groundwater within the basin. A geomorphic map was constructed for this study based on existing soils maps, limited field soil surveys and morphometric analysis. Nine geomorphic surfaces are described, with inferred ages of modern to >73 ka. The geomorphic investigation revealed that the Kowai groundwater allocation zone surface is stepped, with increasing thickness of loess up gradient on the downlands. Near the coast there is intercalated terrestrial and marine sediments, to the west overlying the Kowai Formation are small alluvial fans. In the Waipara Basin the Waipara fan dominates the central portion of the basin, with smaller fluvial and alluvial fans building out from the margins. Groundwater recharge was investigated using chemical, isotopic, water level observations and a simple water balance. It was found that in the Kowai zone the major recharge sources were the rainfall, losses from the rivers and streams. The southern region of the Waipara zone is recharged by rainfall with small contributions from the Kowai River (North Branch). In the South region of the Waipara Basin groundwater recharge is derived from rainfall and losses from streams. The groundwater systems are conceptualized as being topographically driven, with slope – basin floors interactions being an important source of groundwater recharge.

The vegetation of New Zealand has undergone extreme changes during the period of European settlement, with not only forest clearance but a deliberate attempt to replace the native vegetation with species from Europe and later from other parts of the world. Garden escapes continue this process to the current day. Several European ferns that have been introduced to New Zealand gardens have subsequently escaped. At the time of writing D. filix-mas is the most obvious and probably the most abundant in the rural areas of Canterbury having been observed in a wide range of habitats from suburban to farm, to forests both plantation and montane and in shrublands. This thesis investigates some of the ecology of D. filix-mas and explores its potential as a weed detrimental to New Zealand’s indigenous ecosystems. An extensive literature review revealed that in the Northern Hemisphere D. filix-mas grows over a wide range of climates, vegetation types and soils. However the literature review did not clearly show the forest light conditions under which D. filix-mas grows nor could the Northern Hemisphere experience in deciduous woodlands and coniferous forests be directly carried over into New Zealand’s podocarps, evergreen hardwood and evergreen beech forests. An experiment was designed to investigate tolerance to shade and field data was collected at several sites across North Canterbury for subsequent investigation with ordination and standard statistical methods. Records from around New Zealand were collated and used to generate a map of potential extent using the Land Environments New Zealand dataset. Positive growth was achieved under all shade treatments including the heaviest at 96% shade. However the field data suggests that under some of the lowest light availability D. filix-mas does not grow. In the field D. filix-mas is found in diverse habitats with a preference for sheltered sites with more southerly than northerly aspects. Interpretation of the ordination output combined with knowledge of the sites suggests that D. filix-mas is mostly associated with degraded sites and sites of past disturbance. Regenerating kanuka is a reliable place in which to find D. filix-mas but relatively natural beech forest is not. D. filix-mas can potentially grow over much of the South Island particularly in drier areas and can be invasive following disturbance and when grazing is removed, making it a potential problem for indigenous forest restoration efforts.

Geomorphic, structural and chronological data are used to establish the late Quaternary paleoseismicity of the active dextral-oblique Northern Esk Fault in North Canterbury, New Zealand. Detailed field mapping of the preserved c. 35 km of surface traces between the Hurunui River and Ashley Head reveals variations in strike ranging from 005° to 057°. Along with kinematic data collected from fault plane striae and offset geomorphic markers along the length of the fault these variations are used to distinguish six structural subsections of the main trace, four dextral-reverse and two dextral-normal. Displacements of geomorphic markers such as minor streams and ridges are measured using differential GPS and rangefinder equipment to reveal lateral offsets ranging from 3.4 to 23.7 m and vertical offsets ranging from < 1 to 13.5 m. Characteristic single event displacements of c. 5 m and c. 2 m have been calculated for strike-slip and reverse sections respectively. The use of fault scaling relationships reveals an anomalously high displacement to surface rupture length ratio when compared to global data sets. Fault scaling relationships based on width limited ruptures and magnitude probabilities from point measurements of displacement imply earthquake magnitudes of Mw 7.0 to 7.5. Optically Stimulated Luminescence (OSL) ages from displaced Holocene alluvial terraces at the northern extent of the active trace along with OSL and radiocarbon samples of the central sections constrain the timing of the last two surface rupturing events (11.15 ±1.65 and 3.5 ± 2.8 ka) and suggest a recurrence interval of c. 5612 ± 445 years and late Quaternary reverse and dextral slip rates of c. 0.31 mm/yr and 0.82 mm/yr respectively. The results of this study show that the Northern Esk Fault accommodates an important component of the c. 0.7 – 2 mm/yr of unresolved strain across the plate boundary within the North Canterbury region and affirm the Esk Fault as a source of potentially damaging ground shaking in the Canterbury region.

The Cenozoic was a time of climatic, tectonic and eustatic change in the Southern Hemisphere. Cooling at the pole, glaciation and substantial sea ice formation occurred as latitudinal temperature gradients increased and tectonics altered Southern Hemisphere circulation patterns. During this same time frame, the tectonic regime of the New Zealand continental block transitioned from a passive margin to an active plate boundary, resulting in the reversal of a long-standing transgression and an influx of terrigenous sediment to marine basins. In this transition, depositional basins in the South Island became more localized; however, the influence of oceanographic and tectonic drivers is poorly understood on a local scale. Here we apply sedimentological, biostratigraphic and geochemical analyses to revise understanding of the effects of the changing climatic regime and active tectonics on the development of Oligocene and Miocene rocks in the Northern Canterbury Basin. The Late Oligocene to Middle Miocene sedimentary rocks of the northern Canterbury Basin record oceanographic and tectonic influences on basin formation, sediment supply and deposition. The Palaeocene to Late Eocene Amuri Formation in the basin are micrites and biogenic cherts recording deepwater, terrigenous-starved environments, and do not show any influence of active tectonics. The Early Oligocene development of ice on the Antarctic continent and the associated global sea level response is reflected in this basin as the Marshall Paraconformity, an eroded, glauconitized and phosphatised firm ground and hardground atop the Amuri. Sedimentation above this unconformity resumed in the Late Oligocene-Early Miocene with cleaner, deep-water, bathyal planktic foraminifera packstones and wackestones in eastern areas and Late Oligocene inner shelf volcaniclastic packstones in parts of the western basin. Post-unconformity sedimentation resumed earlier in western areas, as the currents responsible for scouring the sea floor moved progressively to the east. The development of tectonic uplift in terrestrial settings is first seen in the northwestern basin in Lower Miocene fine quartz-rich sandstones, and by the Middle Miocene, bathyal sandstones and quartz-rich wackestones appear in the basin, replacing earlier, more pure carbonates. The uplift caused shallowing to the west, in the form of shelf progradation due to sediment influx. This shallowing is not observed to the east; instead, the palaeoenvironments show a deepening as a result of sea level rise.