Within this area are developed a series of quartz veins which cut three rock types, the Grainsgill granite, part of the southern margin of the Carrock Fell gabbro to the north, and an intervening area of hornfels belonging to the Skiddaw Slate Series. Both the hornfels and the gabbro have suffered thermal metamorphism due to the granite, and in addition, the hornfels has undergone a very localized metamorphism due to the gabbro. All three rock types have undergone a further hydrothermal alteration due to the quartz veins. The microscopic changes involved in this alteration are described and it is shown that the end product in each case is essentially similar to a greisen, with the addition of pyrite and arsenopyrite.

Ocellar hybrid rocks, formed by metasomatic transformation of basalt xenoliths engulfed in granitic magma, are characterized by numerous small, oval quartz porphyroblasts, each sheathed with narrow rims of amphibole. The progressive development of these quartz ocelli, together with the general texture of the ocellar hybrid, is traced through a number of intermediate hybrid types. In some instances, the ocellar hybrid displays an intrusive relationship toward basalt and is thought to have undergone a certain amount of metasomatic mobilization.

An account is given of the petrography and chemistry of a diopside-orthoclase-hornblende rock within the quartzose garnetkyanite-biotite granulites of the Leverburgh Lewisian paragneiss belt of South Harris.

An outcrop of siliceous, conglomeratic grit is described on the margin of the Dartmoor granite near Woolley, and is considered to be probably of Oligocene age.

Vermiform burrows, which are common in the Lower Greensand, can be used to estimate the relative rate of sedimentation, repeated penetration by burrowing organisms being taken as indicating slow deposition, a single undisturbed penetration as indicating rapid deposition. Application of this criterion is illustrated by reference to the Ferruginous Sands of the Isle of Wight.

Some thousands of Australian coal samples have been studied at the Division of Coal Research, C.S.I.R.O. On the basis of these studies, the present usage of the term “sclerotinite” is considered and possible justifications for the retention of this maceral category are outlined and discussed. No characteristic differences in physical properties, form, or utilization behaviour have been found whereby sclerotinite may be distinguished from the other macerals of the inertinite group. Most of the material which has been referred to as sclerotinite is probably not fossil fungus. The “discrete body” category of sclerotinite may well represent fusinized resin bodies, while the more extensive material represents degraded plant tissue. There would appear to be no case for the retention of the maceral category sclerotinite, and alternative means are suggested of classifying for petrographic analysis material which has hitherto been regarded as coming within this category.

The occurrence of numerous washout structures in the Appin Quartzite is recorded and the criteria by which they are recognized discussed. It is concluded that these structures are reliable for the determination of the way-up of beds and that their association with current and graded bedding indicates a turbid deltaic environment of sedimentation.

The 1953 earthquake at Suva in the Fiji Islands caused submarine subsidence at the outer edge of the coral reef near Suva. Sixty miles of the cable from Suva to Norfolk Island was either buried or shifted about 2 miles from its original position. The damaged cable followed close to the centre of a submarine valley that extends out from the coral reef near Suva. A length of cable recovered from the ocean bottom 40 miles from Suva is damaged in a way that indicates that it was eroded while lying partly buried in sediments and was then torn up and twisted. A wire hawser found attached to the cable had been cleaned by sandblasting. It is inferred that the cable was damaged by a turbidity current that originated at the submarine subsidence, that the current had a velocity of at least 10 miles an hour, and that it travelled for at least 70 miles.

Postdepositional low-temperature mineralogical changes in Carboniferous sedimentary rocks from Vestspitsbergen are described. These include the crystallization of apatite, quartz, and feldspar, and the replacement of feldspar and quartz by calcite and dolomite. Minerals of the chalcedonite–lutecime–quartzine group also occur.

The orientation of quartz in small shear folds, which belong to two movement episodes, is considered to result from laminar flow along the axial plane surfaces. The locations of fabric maxima and girdles are controlled by the orientation of the a–kinematic axis, which in shear folds may not be normal to the fold axis, and the shear surfaces. The earlier fabric consists, essentially, of paired maxima arranged systematically about the axial plane; ac–girdles are absent. The explanation of the near-orthorhombic symmetry of the first fabric in terms of a late “flattening” overprinted upon the previously-formed fold is not favoured: quartz orientation developed during the first folding. The later fabric results from the recrystallization of quartz grains with their largest dimensions and c–axes parallel to the calculated a–kinematic axis of second folding.

It is suggested that the Scotia Arc was formed after the disruption of a continental strip between South America and Antarctica by an eastward advance of the Pacific crust; volcanic island arcs and associated trenches developed at the juction of the Pacific and Atlantic crustal types; the Scotia Arc migrated eastward with time; and that the crustal structure of the Scotia Sea is in the process of changing from an oceanic (Pacific) to a continental type.