Journal and Proceedings of
The Royal Society of New South Wales
Volume 106 Parts 3 and 4 [Issued February 6th, 1974]
CONTENTS
| AUTHORS & TITLES | PAGES |
| Sims, K.P., Occultations Observed at Sydney Observatory during 1972 [No Abstract] | 81-83 |
| Roberston, W.H., Precise Observations of Minor Planets at Sydney Observatory during 1971 and 1972 | 84-88 |
| Rankama, Kalervo, The Late Precambrian Glaciation, with Particular Reference to the Southern Hemisphere [Clarke Memorial Lecture – No Abstract] |
89-97 |
| Korsch, R.J., Structural Analysis of the Palaeozoic Sediments in the Woolgoolga District, North Coast, New South Wales | 98-103 |
| Dulhunty, J.A., Potassium-Argon Basalt Ages and their Significance in the Macquarie Valley, New South Wales | 104-110 |
| Prokhovnik, S., Slow Transport as a Criterion for Synchronizing Clocks | 111-114 |
| Van der Poorten, A.J., A Note on Recurrence Sequences | 115-117 |
Vol 106 pts 3-4, pp.84-88
Precise Observations of Minor Planets at Sydney Observatory during 1971 and 1972
W.H. Robertson
Abstract. Positions of 2 Pallas, 3 Juno, 4 Vesta, 6 hebe and 7 Iris obtained with the 23 cm. camera are given
Vol 106 pts 3-4, pp.98-103
Structural Analysis of the Palaeozoic Sediments in the Woolgoolga District, North Coast, New South Wales
R.J. Korsch
Abstract. Macroscopic folds in the Coffs Harbour Beds are upright equant planar cylindrical folds with straight hinges. Folds are open in the north and adpressed to isoclinal in the south. Plunges change from subhorizontal in the north to steep in the south. These progressive changes can be explained by the simple theory of a southward increase in the dip of bedding relative to a stress field (and cleavage) of constant orientation. The theory is applicable if the strikes of bedding and cleavage are slightly different.
A reticulate cleavage, parallel to the axial planes of the folds, is present and one intersection with the bedding is homogeneous with the fold axis.
The beds have been affected by three phases of deformation. The first was a soft-sediment slumping and the other two were tectonic in origin, both being related in time to the Hunter-Bowen Orogeny. The second deformation produced mesoscopic folds and the axial-plane reticulate cleavage whereas the third deformation formed small scale monochnes in the bedding and cleavage.
The Redbank River Beds have suffered two tectonic deformations but these cannot be related to the deformations in the Coffs Harbour Beds. The first deformation produced tight folds, often isoclinal in style, and the second formed gentle warps on the limbs of the tight folds.
Vol 106 pts 3-4, pp.104-110
Potassium-Argon Basalt Ages and their Significance in the Macquarie Valley, New South Wales
J.A. Dulhunty
Abstract. Potassium-Argon ages and modes of occurrence are recorded for Tertiary basalt flows in and near the Macquarie Valley region, and considered in relation to Tertiary volcanism geomorphology. Two age groups of Tertiary basalts occur. An older, mainly Eocene group, of the order of 40 to 55 m.y. was extruded in eastern areas of the region and now rests on remnants of an early or pre-Eocene surface along and near the Main Divide. A younger, or middle Miocene group, of the order of 11 to 15 m.y., was extruded across the region before tilting of the Western Slopes and subsequent removal of basalt from eastern areas, entrenchment of the Macquarie River to 60 m below the base of the basalt at Bathurst, and burying of basalt beneath river alluvium in western areas near Dubbo. Results for the Macquarie region correspond with similar results previously recorded for regions to the north along the Western Slopes.
Vol 106 pts 3-4, pp.111-114
Slow Transport as a Criterion for Synchronizing Clocks
S.J. Prokhovnik
Abstract. If a clock is transported slowly from one point to another of an inertial system, the time-dilatation effect is small and varies with the velocity of transport. This variation permits detection of and compensation for the effect, thus providing a procedure for synchronizing separated clocks, which is equivalent to Einstein's light-signal convention. However, clocks so synchronized, with respect to a given inertial system, will not appear synchronous with respect to any inertial system. It is shown that the substratum formulation of Special Relativity provides a satisfactory interpretation of this phenomenon. Consideration is also given to the relation between the criteria for clock-synchronization and the status of light-velocity measurements.
Vol 106 pts 3-4, pp.115-117
A Note on Recurrence Sequences
A.J. van der Poorten
Abstract. Sequences satisfying linear homogeneous difference equations (recurrence sequences) over a commutative ring R are investigated with a view to demonstrating without appeal to analytic techniques that the set of all such sequences is an R-algebra with respect to termwise operations. Explicit formulae are provided.