The concept of tectonic regimes is developed so as to specify the symmetry and orientation of bulk deformation for use in tectonic analysis. Four symmetry patterns combined with possible arrangements of principal axes in vertical and horizontal directions as in a compression belt give thirteen regimes which are in turn defined and tentatively related to some known tectonic structures. A theoretical orogenic sequence of regimes is developed and the paper concludes with a review of some of the difficulties.

Karroo sedimentation in the mid-Zambezi area presents an instance of deposition in an intra-cratonic basin during a complete climatic semi-cycle. Mention is made of the tectonic factors which controlled the course of Karroo sedimentation in the area, and the nature of the pre-Karroo surface is commented upon. An account is given of the depositional history of the mid-Zambezi basin during the Karroo period. The structural development of the region since Karroo times is outlined, and it is suggested that the present valley is essentially a downwarped and eroded part of the peneplain which still forms the adjacent plateau to the north-west.

The presence of locally abundant pebbles of Middle Devonian Limestone in the New Red Sandstone near North Tawton, Devonshire, is recorded. It is suggested that these were derived in Permian times from a nearby outcrop of Devonian limestones which projected through the Culm Measures of the mid-Devon syncline.

Alternation of morphogenetic systems conditioned by wide swinging of climatic belts equatorward and poleward has been used to explain otherwise puzzling relict forms in many regions. A characteristic finely dissected landscape relief prevalent in some middle-latitude regions is in strong contrast with smoothed, coarse-textured, whalebacked, relatively featureless relief in others, notably western Europe, which are now in the humid-temperate zone. This latter is believed to be relict from the periglacial regimes of Pleistocene ice ages. In New Zealand where the former landscape type is typically developed, there has also been quite strong “periglaciation”, and in Europe running-water erosion cannot but have operated to some extent in interglacial ages. It appears that the periglacial smoothing has been pushed to the extreme limit in Europe but that its effects have been neutralized in New Zealand by the vigour of dissection in the alternating warm ages. Periglacial smothering, or “fossilization”, of fine-textured relief, which has been followed by renewed fine dissection, is very common at Wellington, New Zealand. The reasons are not clear why running water should have been (and should still be) more efficient in dissecting the New Zealand landscape than that of Europe, so that the relict periglacial landscape remains intact in the latter region.

Geological information obtained by core sampling of the solid rock underlying the loose deposits on the floor of the Western Approaches is set forth. Discoveries of interest include those of Chalk in the area north-west of Cornwall and of nepheline phono-lite from Epson Shoal, 6 miles east of the Wolf Rock. Other samples obtained very probably represent the Devonian, New Red Sandstone and Chalk, and on the basis of the identifications a geological map has been prepared showing the approximate distribution of these formations in the area.

The age of zircon from the Kunait pluton in south-west Greenland has been measured by the lead-alpha method. The experimental data indicate a Cambrian age and the bearing of this result on the general geology of the area is briefly discussed.

A bone found in the peat near King's Lynn, Norfolk, has been identified as belonging to a pelican. This is the fifth fossil record from East Anglia but it is the first to be accurately dated, and it can be correlated with Godwin's pollen zone VII–VIII (Iron Age). Other fossil pelican bones from East Anglia and Somerset are identified as those of the Dalmatian Pelican rather than the White Pelican which now visits parts of north-west Europe.

The Woolridge Terrace gravels of the lower Severn are re-examined, and certain high-level gravels west of the Severn valley examined for the first time. It is concluded that the deposits are of two different ages. The older series is probably the outwash of a Severn valley glacier, the younger was laid down by a stream coming from the Silurian hills near Ledbury. A Gipping age is suggested for both.