Following the 2001 December 7 Jackson Bay earthquake (M-L 6.2, M-W 5.8), a temporary network of five portable seismographs was deployed in the region to record aftershock activity. Data recorded by the temporary network and nearby New Zealand National Seismological Network stations have been used to define a velocity model for the region and station corrections for each recording station. The locations of the best recorded aftershocks and the revised location of the mainshock indicate that the Jackson Bay earthquake sequence occurred 3-10 kin to the east of the Alpine Fault, which is vertical in this region. A fault plane solution obtained from body-wave modelling suggests the mainshock was primarily a reverse event (rake = 103 degrees) centred at c. 4 km depth on a fault striking northeast-southwest (48 degrees) and probably dipping to the southeast (45 degrees), which is roughly consistent with the Harvard CMT solution for this earthquake. However, on examination of the aftershock locations, such a fault plane is not clear, nor is any other. The aftershocks are located mainly in two clusters near each other at depths between 3 and 8 km and aligned approximately north-south. Their positions are in accord with induced stress considerations and the mainshock fault plane lying between the clusters. Individual focal mechanisms for 33 aftershocks have a wide range of solutions. As a group, however, their P and T axes are reasonably well aligned and consistent with the background stress regime in the region as determined by direct inversion of P-wave polarities. The Jackson Bay earthquake was the third thrust earthquake of magnitude > 6 to occur just cast of the Alpine Fault in a 7 yr period. Consideration of the mechanics of this earthquake, and the previous two, suggests that the regional stress is at a high level, in accord with the long elapsed time since a large Alpine Fault event. Although the area is small, the Jackson Bay mainshock induced a mainly positive change in Coulomb Failure Stress (CFS) on the closest section of the Alpine Fault, up to c. 0.7 MPa (7 bars).

Assessing dietary protein of colobus monkeys through faecal sample analysis: a tool to evaluate habitat quality Colin A. Chapman*, Terry Webb, Raime Fronstin, Michael D. Wasserman and Ada Mayte Santamaria Department of Zoology, University of Florida, Gainesville, FL 32611, Wildlife Conservation Society, 185th Street and Southern Boulevard, Bronx, NY 10460 and Metro Zoo Miami, One Zoo Boulevard, 12400 S.W. 152nd Street, Miami, FL 33177, U.S.A.

The Mw 6.1 Thompson Sound earthquake occurred on I November 2000, with an epicentre near the Fiordland, New Zealand, coastline (-45.112degrees, 166.952degrees). Aftershocks, recorded on temporary seismographs as well as the National Seismograph Network, define a 12.5 x 12.5 km planar zone, taken as the mainshock fault, with a strike of 175degrees and dip of 65degreesW, ranging in depth from c. 12 to 24 km. This is in accord with the mainshock focal mechanism determined by a body-wave inversion that indicates a rake of c. 590, that is, mainly thrust motion with a component of left-lateral strike-slip. This event follows a series of moderate to large earthquakes in the Doubtful Sound region: Te Anau, 1988, Mw 6.7, depth 60 km; Doubtful Sound, 1989, Mw 6.4, depth 24 km; Secretary Island, 1993, Mw 6.8, depth 22 km. The Secretary Island event was a thrust event near, or on, the subduction interface, with a dip of 30-40degreesSE, and our interpretation is that both the Doubtful and Thompson Sound events were oblique thrusts (with a left-lateral component) above the interface and shoreward of the Secretary Island earthquake. The Coulomb failure stress induced by all three large events prior to the Thompson Sound event would have loaded closer to failure faults such as that at Thompson Sound. Together, the four events induced a pattern of Coulomb failure stress on the nearby Alpine Fault that varies in sign with depth. Overall, little can be said about potential triggering or bringing forward/retarding of a large Alpine Fault event. Strong motion recordings for the Thompson Sound event are few, but peak accelerations are in accord with existing attenuation relationships.

We have studied 18 earthquakes of M-w > 5.5 within the North Island, New Zealand region to determine fault parameters for earthquake hazards and regional tectonic studies. Since most large (M-w > 6.5) earthquakes in the North Island occurred prior to 1961, these events provide important information to supplement studies of more recent seismicity. Our results indicate that no large plate interface earthquakes have occurred in the central and southern North Island for the past 80 years, although six strike-slip earthquakes of M-w greater than or equal to 6.8 occurred within the Australian (upper) Plate during an extremely active 25 year period that began in 1917. Only the M-w > 7.2 strike-slip events were associated with surface faulting, indicating the difficulties that may arise in attempting to identify active faults within this region. Two earthquakes (M-w = 6.9-7.1) off the northeastern North Island in 1947 appear to have occurred along the plate interface and were associated with local tsunamis having runup heights of up to 10 m. Two M-w = 6.8 events also occurred within the Pacific (lower) Plate, highlighting the hazards related to intraslab events. Slip vectors for the earthquakes studied suggest that the majority of transcurrent motion along the plate margin is accommodated within the Australian Plate, similar to the results obtained from studies of more recent, smaller earthquakes. Pure thrusting occurs along the plate interface and T axes of intraslab events indicate downdip tension in the Pacific Plate.

SUMMARY The (1994) Arthur’s Pass earthquake (Mw 6.7, South Island, New Zealand) had a complex aftershock sequence including events aligned with major mapped faults. To determine whether the major NE‐SW-trending strike-slip faults in the region were activated during this aftershock sequence, we investigate the largest well-recorded aftershocks. The Arthur’s Pass earthquake itself was a reverse-faulting event, but the majority of the aftershocks were strike-slip. We use the empirical Green’s function method to obtain source time functions for four aftershocks (ML 4.1‐5.1). We then invert for slip on each nodal plane and compare the variance reduction to determine which is the fault plane. The two largest earthquakes (ML 5.1 and ML 4.2) located close to the mapped trace of the Bruce fault both occurred on fault planes striking NNW‐SSE, perpendicular to the strike of the Bruce and other regional strike-slip faults. The third earthquake studied (ML 4.1), located on a lineation of aftershocks parallel to the regional mapped trend, had a preferred fault plane with a NE‐SW strike. The fourth aftershock (ML 4.1) was located close to the main-shock fault plane and had an oblique reverse mechanism. This earthquake exhibited northward directivity, but the fault plane could not be identified. The earthquake stress drops ranged from 1 to 10 MPa.

On 24 November 1995 an earthquake of moment magnitude M-W 6.2 struck near the small settlement of Cass in the Southern Alps, South Island, New Zealand. Body-wave modelling using teleseismic arrivals gives an oblique reverse focal mechanism for the mainshock, with the fault plane striking approximately north-south, and a shallow centroid depth of 3-6 km. Aftershock recordings at the station SNZO near Wellington were used as empirical Green's functions to estimate a source time function duration of 7 s. A joint inversion for velocity and location of 169 selected events was used to derive a one-dimensional velocity model with station terms, and this velocity model was then used to relocate all recorded aftershocks. A subset of the best 803 events was then selected for further analysis. The apparent trend of the aftershock zone is NNW-SSE, with the mainshock near the centre. However, projections of the aftershocks on north-south and east-west cross-sections show a band of activity shallowing to the south and dipping to the west. The north-striking, west-dipping nodal plane of the mainshock focal mechanism is therefore most likely to be the fault plane. Early aftershocks occurred mainly to the south of the mainshock location, suggesting rupture to the south, a feature supported by the mainshock modelling. The aftershock focal mechanisms are mixed but reflect the regional stress field (NW-SE compression).

We present the results of body waveform modelling studies for 17 earthquakes of M-w greater than or equal to 5.7 occurring in the South Island, New Zealand region between 1918 and 1962, including the 1929 M-s = 7.8 Buller earthquake, the largest earthquake to have occurred in the South Island this century. These studies confirm the concept of slip partitioning in the northern South Island between strike-slip faulting in southwestern Marlborough and reverse and strike-slip faulting in the Buller region, but indicate that the zone of reverse faulting is quite localized. In the central South Island, all historical earthquakes appear to be associated with strike-slip faulting, although recent (post-1991) reverse faulting events suggest that slip partitioning also occurs within this region. The difference between historical and recent seismicity in the central South Island may also reflect stress readjustment occurring in response to the 1717 AD rupture along the Alpine fault. Within the Fiordland region (southwestern South Island) none of the historical earthquakes appears to have occurred along the Australian/Pacific plate interface, but rather they are associated with complex deformation of the subducting plate as well as with deformation of the upper (Pacific) plate. Two earthquakes in the Puysegur Bank region south of the South Island suggest that strike-slip deformation east of the Puysegur Trench is playing a major role in the tectonics of the region.

The upgrade of the New Zealand National Seismograph Network in the late 1980s has enabled more accurate earthquake locations to be determined. The catalogue data for events occurring from January 1990 until the end of February 1993 show some new patterns that have not been identified in previous observation periods, and also confirm the persistence of some phenomena observed previously, such as the aseismic corridor through the Nelson region. The deep seismicity data show spatial patterns remarkably similar to those for higher magnitude events recognised by Reyners in 1989. The Hikurangi Benioff zone is marked by intense seismic activity at depths between 150 and 200 km beneath the Central Volcanic Region; it has a sharp discontinuity beneath northwest Nelson and it extends as far southwest as Westport. The Fiordland Benioff zone is distinctly more seismically active in its northern block, and activity is noticeably concentrated in a zone to the west of Lake Te Anau.Shallow earthquakes (depth <15 km) for the period 1990 to February 1993 outline the active eastern boundary of the Central Volcanic Region and an east-west band running from Mt Ruapehu to Mt Taranaki. Earthquakes in this latter group also extend to deep crustal levels and they, and some recently recognised faults in this area, are probably related to a crustal discontinuity in this region. The Cape Egmont Fault Zone has been particularly active during this observation period. In the South Island, the 1990 Tennyson earthquake appears to have triggered activity along the Awatere Fault. The Alpine Fault is seismically quiet in the section from Harihari to Jackson Bay. A band of earthquakes lying to the east of the fault north of Harihari may represent activity associated with the Alpine Fault at depth although this cannot be confirmed by existing data. At the southern end of the Alpine Fault, two subparallel lineaments appear to form the boundaries of the western end of the Otago Range and Basin Province, but they are not associated with any known tectonic feature. In the Wellington region, the earthquakes shallower than 15 km are concentrated in the area between the Wellington and Wairarapa Faults. A group of earthquakes near Carterton possibly represents the interaction between two fault systems of different trends in that area. A very sharp northeast-southwest trending boundary between the very active shallow seismicity of the Wanganui Basin and the aseismic Marlborough Sounds is probably linked to subduction. Earthquakes in the Benioff zone underlying the Wellington region show a gap beneath the Wairarapa Basin.

The ability to distinguish foreshocks from background seismicity is very important in short-term earthquake prediction. To that end we have looked at spatial clustering (using waveform cross-correlation) and stress drops of foreshocks of two New Zealand earthquake sequences that occurred in 1990. The Tennyson sequence, located in a continental margin-type strike-slip environment, consisted of a group of foreshocks, an ML = 5.8 mainshock, and many aftershocks. A cross-correlation analysis showed five spatially close clusters of activity prior to the mainshock. Two were event pairs located within the final aftershock zone, two were clusters of four events, each located outside the aftershock zone, and the fifth was a cluster of eight immediate foreshocks loated within the aftershock zone. An analysis of two nearby control regions showed that pairs of identical events were not uncommon, but larger clusters were. Stress drops of three events in the 12 days before the mainshock, obtained by deconvolving small events as empirical Green's functions, were lower than for earlier preshocks and aftershocks. Source time functions derived from the Green's function deconvolution indicated that a unilateral rupture model was more appropriate than a circular source model. Cross-correlation values from the ML = 5.9 Weber sequence also showed spatial clustering, but this was well removed from the mainshock in space and time. A control area also showed similar clustering, suggesting that it is a normal feature of the seismicity at a convergent margin. The Weber foreshocks, only four in all, were not highly correlated. For both sequences, foreshocks did not correlate with the aftershocks, indicating that they occurred in a region of complete coseismic stress relief. A stress drop of 1650 bars was obtained for a 44-km-deep event that occurred within the upper part of the subducting Pacific Plate, nearby, but not related to the Tennyson sequence.

The plate motion model NUVEL-1 predicts oblique convergence between the Pacific and Australian plates in the South Island of New Zealand. We used P and SH body waveform analysis to constrain the focal mechanisms of the 15 largest earthquakes (M(S) > 5.8) that have occurred in this region since 1964, in order to see how the plate motion is accommodated. At the southern end of the Alpine Fault, convergence is achieved by oblique slip movement along a concentrated zone of deformation. In the southern offshore region one event may be related to thrusting of the Australian plate beneath the Pacific plate, and another strike-slip event probably demonstrates movement on an active strike-slip fault system parallel to, but offset from, the southern limit of the Alpine Fault. This geometry provides a possible mechanism for the rapid uplift of the Fiordland region. Deformation in the northern South Island is more distributed. In the south-west Marlborough region partitioning occurs between strike-slip faulting in the SE and reverse faulting farther NW in the Buller region. We suggest that the partitioning developed as a consequence of an increasing component of shortening that was accommodated by slip on reactivated pre-existing normal faults in the Buller region. Shortening in the Buller region may have deflected the NE end of the Alpine Fault towards the NW, forming the prominent bend. The Marlborough Fault System, with its youngest and most active faults to the SE, probably developed in an attempt to maintain a through-going strike-slip structure as each of the strike-slip faults was transported towards the north-west. Partitioning of the opposite polarity (with reverse faulting SE of the strike-slip faulting) occurs in north-east Marlborough. The boundary between the two different styles of partitioning in NE and SW Marlborough appears to coincide with a change in the nature of the downgoing slab and a change in strike of faults of the Marlborough Fault System. A normal faulting earthquake on the northern edge of the Chatham rise probably results from a complex interaction of the buoyant continental crust in that region with the subduction zone and the overlying Marlborough Fault System.

Source parameters of the M L 5.7,19 July 1985 earthquake of northern Hawke's Bay, New Zealand are determined by modelling the teleseismic P and S body waves. A focal depth of 31 ± 1 km, scalar moment 5.6×10 17 Nm and source duration of 3.0–3.5 s are estimated. The focal mechanism (strike 224°, dip 78°, rake 273°) shows normal faulting on a NW-dipping plane that is parallel to the strike of the subducted Pacific Plate. Thirty-five aftershocks were recorded by a temporary seismograph network, 21 of which were relocated using the JHD method. The hypocentres define a northwest dipping plane, 20×30 km, which extends from the hypocentre of the mainshock to a depth of 47 km. The position of the subducted plate in Hawke's Bay is well defined from previous micro-earthquake studies. In the region of the mainshock the plate interface is located at a depth of approximately 28 to 30 km, placing the hypocentre of the mainshock in the crust of the Pacific plate. The extent and location of the aftershock distribution suggest that the mainshock ruptured downward and extended through the crust of the plate. This event thus differs from other normal faulting events in the region that usually occur in the mantle of the subducted plate. The scalar moment at long periods ( T > 45s, Dziewonski et al., 1986) exceeds that determined here by a factor of 2, suggesting a source rich in long period energy, an idea supported by the relatively large aftershock area.

Long-period body-wave modelling of the main shock of the 1987 March 2 Edgecumbe earthquake sequence reveals a multiple rupture event with a moment of 4. 3 × 1018 N m. The first rupture originated at a depth of about 8 km and propagated to the surface and to the southwest. A second subevent occurred about 3 s later with an epicentre about 9 km to the southwest of the main-shock epicentre. The focal mechanism of the first subevent shows dominantly normal faulting. Comparison with the surface fault break indicates that the northeast-striking, northwest-dipping nodal plane was the fault plane and hence the horizontal slip vector trend was approximately 342°. The second subevent may correspond to the faulting observed on the Te Teko trace.

The matrix used to prepare control material for the Chemical Pathology Quality Assurance Programme Group of the Royal College of Pathologists of Australasia/Australian Association of Clinical Biochemists (RCPA/AACB) was investigated to identify a contaminant affecting the gas-liquid chromatography (GLC) analysis of valproic acid (VPA). The contaminant, not present in patients' sera, eluted with the octanoic acid internal standard in our GLC procedure. The compound was identified as octanoic acid. The source of this contamination could not be determined. The presence of endogenous octanoic acid in the RCPA/AACB quality control material precluded the use of octanoic acid as an internal standard.

The M l = 6.2 Gisborne earthquake of March 4, 1966 occurred along the East Coast of the North Island, New Zealand. Modeling of P and S body waves shows that the focal mechanism of this event is consistent with northwestward thrusting of the Pacific Plate beneath the North Island ( ϑ = 249°, δ = 25° and λ = 131°). The focal depth is constrained to 18 km, significantly less than the values of 25–30 km computed from local network data. Estimates of the scalar moment, source duration and stress-drop for the event are 4 × 10 24 dyne-cm, 2–3 s, and 20–120 bar, respectively. Cross-correlation errors of synthetic to observed waveforms were computed for all possible P and T axis locations and slip vector orientations and contoured on a projection of the focal sphere. The error contour at which the synthetic waveforms distinctly diverged from the observed waveforms was established by eye. The procedure shows that the analysis of long-period body waves, at least in this case, provides much better constraint on focal mechanism orientation than does first motion data alone.

This paper examines the relationship between organisation structure and management style and their influence on organisational effectiveness measured in both ‘human’ and financial terms. Account has also been taken of related contextual factors such as differences in task, size and environment of a company. Using information collected from a sample of fifty small and medium size printing and building firms the authors have elaborated a conceptual model involving the independent attributes; integration, control, task orientation and people orientation. The validity of this model has been operationally tested and examined against the background of evidence reported by other research workers on the contextual determinants of organisational structure and management style. Substantially different patterns of association between ‘organisation’ and ‘style’ and company performance are found for the two industries and an important outcome of the research has been to produce further evidence in favour of the contingency theory of organisation. The paper concludes with some implications for management practice and organisational design.