Thesis (M.S.) University of Delaware, 2006. / Principal faculty advisor: Frederick E. Nelson, Dept. of Geography. Includes bibliographical references.

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Navigation by satellite---GNSS---is a local technology with global repercussions. Although operation and control rest in government hands, the consequences of satellite use, most often beneficial, have a worldwide effect. Controversy arises when this free-of-direct-charge technology, on which the International Community relies, fails, thus causing damage to third parties. / It was the intention of the drafters and negotiators of the international space law regime to establish a victim-oriented liability framework, in order to guarantee adequate compensation for damage caused by space activities. Unfortunately, it seems that the present regime has only partially met these goals. / The surest means of obtaining compensation is through domestic legal regimes, but these regimes are naturally subject to the ebb and flow of government policy and judicial discretion. / The present thesis will analyse the established liability regimes for which a damaged GNSS final user may seek compensation, and will finally consider whether the drafting of a GNSS Convention is opportune.

The Global Satellite Navigation System (GNSS), the core of the International Civil Aviation Organization (ICAO) Communication, Navigation, Surveillance/Air Traffic Management concept is capable of supporting future aviation needs. The implementation of this revolutionary technology however remains overshadowed by a series of complex institutional and legal issues. The extraterritorial control and ownership of existing GNSS systems coupled with the dual character of this technology poses a serious threat to the concept of national sovereignty as traditionally understood. This is further aggravated by the fact that there exists only one de facto GNSS signal provider, thus placed in a position to impose its own conditions without reference to the requirements of the rest of the world. / In an attempt to secure both European political independence and a fair share in the global GNSS market Europe has decided to play an active role by launching Galileo, an autonomous global constellation under the control of civil authorities scheduled to be operational by 2008. / The present thesis analyses the desirability of a suitable legal and institutional GNSS framework to achieve universal acceptance of the GNSS. However, in the context of the present status quo it is unrealistic to expect that the only GNSS signal provider surrender its nationally procured system under the umbrella of an international instrument. National security concerns and industrial policy goals underlie this tendency. The present situation may turn different when the incumbent GPS faces the competition of Galileo, an alternative civil system willing to offer firm legal guarantees of service performance albeit in exchange for a fee. The entire viability of this theory remains however dependent upon the European capability of defining a successful business case for Galileo.

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The measurements from eighteen GPS (Global Positioning System) surveys and four terrestrial surveys were used to calculate the velocities of 406 survey stations throughout the South Island, Stewart Island and the southernmost North Island. Repeated GPS measurements are available at 350 stations. The calculation of the velocities for the remaining stations is made possible through the use of terrestrial measurements. The velocity was modelled under the assumption that the displacements of the stations are either linear with time or linear punctuated by discontinuities. The discontinuous model was used to estimate the coseismic displacements of stations in the vicinity of the 1994 Arthur�s Pass earthquake (M 6.7). The maximum station displacement was estimated to be ca. 40 cm, and significant displacements are seen to a range of ca. 70 km from the earthquake epicentre. Station displacements were also calculated for two later earthquakes in the vicinity of the Arthur�s Pass earthquake, but it was not possible to separate these from the postseismic displacements due to the earlier earthquake. A continuous velocity field was estimated from the discrete station velocity measurements through a stochastic model based on the concept of minimum curvature. The selection of the basic stochastic model was effectively arbitrary; however, the model was refined to better suit the velocity field in the South Island. This was achieved through estimating the correlation between the velocity components (east and north) and the anisotropy of the velocity field. The stochastic model has the advantage over other models (e.g. polynomials or splines) in that only the probable shape of the velocity field is assumed. Therefore, the shape of the velocity field is not restricted by a priori model assumptions. The measurement of the differential velocity across the South Island plate boundary between Christchurch and Cape Farewell is less than 85% of the interplate velocity calculated from NUVEL-1A. One possibility is that the NUVEL-1A model may not be an accurate representation of the motion at this plate boundary. Alternatively, deformation (occurring during the period of survey measurements) may extend a total distance of 150 km or more (assuming that the spatial velocity differential is less than 5x10⁻⁷/year) offshore from Christchurch and Cape Farewell. In the southern South Island there is evidence for as much as 22 mm/year of east directed motion being accommodated between Fiordland�s west coast and the stable interior of the Australian Plate. An accretionary wedge has been imaged west of Fiordland (Davey and Smith, 1983; Delteil et al., 1996); therefore, some of this deformation may be related to slip on the subduction interface. The shear strain rates are clearly influenced by the dominant fault elements in the South Island, i.e. the southern and central Alpine Fault, and the eastern Hope Fault. The maximum measured shear strain rate in the South Island, 6(±1) x10⁻⁷/year, occurs adjacent to the Alpine Fault at (1 70.5°E, 43.3°S), ca. 40 km northeast of Mt Cook, and is coincident with a local dilatational strain rate minimum, -7 (±4.5) x 10⁻⁸/year. This is the only location where the measured strain rate is compatible with strike-slip and dip-slip motion on the Alpine Fault. Shear strain rates decrease eastwards along the Hope Fault: from 5(±0.7) x10⁻⁷/year at the Alpine Fault, to 3(±0.8) x10⁻⁷/year close to the Jordan Thrust. The zone of deformation broadens with a concomitant decrease in shear strain rate, such that within the northeast South Island there is no distinct maximum over any particular fault. A band of contraction and shear has been imaged at a distance of 100 km southeast of, and parallel to, the Alpine Fault. The deformation at this location may be related to a frontal thrust zone similar to that described in the two-sided wedge models. The band of deformation continues north of Christchurch, intersecting the Porters Pass Fault Zone. Significant contraction rates are seen in the measurements from four other zones. The first of these is situated towards the northeast (on land) ends of the Clarence, Awatere and Hope Faults. Some of this signal is presumably related to the uplift of the Seaward and Inland Kaikoura Ranges. The three remaining zones of significant negative dilatational strain rate are located north of the Wairau Fault, close to Jackson Bay and within central Otago. A zone of significant shear strain rate is measured along the eastern side of, and within southern Fiordland. The deformation measurements probably partially reflect the existence of an important fault running through Lake Te Anau, which accommodates the motion of the Fiordland block relative to the Pacific Plate. The remainder may be due to internal deformation of the Fiordland block. A new velocity differential measurement has been introduced, the rotational excess. This function of the shear strain rate, vorticity and dilatational strain rate should be sensitive to tectonic rotation (as measured by paleomagnetic data). Point estimates of the rotational excess are insignificant throughout the South Island. Also, there are no easily defined regions in which spatially averaged measurements are significant. If the rotational excess is assumed to be a direct measurement of tectonic rotation then the measurements place a bound on the size of the region and the rate at which it rotates. For example, the rate of tectonic rotation within a square region with side lengths of 50 km located adjacent to Cape Campbell is unlikely to be greater than 4°/Ma. However, greater tectonic rotation rates are possible within smaller regions.