Grain-size distribution and mineralogical composition are independent variables in most detrital sediments. Separate classifications are necessary to describe these sediment attributes. Essential characteristics are given when the following format is used: (sorting term) (size term): (cement) (prominent nondetrital) (detrital composition). This polynomial evokes a clear mental image of the sediment. Descriptive nomenclature and procedure are modified from earlier Folk publications. The resultant classification system is objective and practical. Gravel, sand, silt, and clay are end members of triangular diagrams that are divided into named textural categories in accord with apparent natural groupings. Modal size and sorting terms supplement the names of some categories. Rudite, arenite, and lutite are used in a compositional sense for detrital sediments whose texture is respectively indicated by the terms gravel (conglomerate or breccia), sand (sandstone), and mud (mudstone, siltstone, or clayston...

https://www.tandfonline.com/doi/pdf/10.1080/00288306.1970.10418211

Detrital sedimentary rock classification and nomenclature for use in New Zealand

A computer fit of the 500-fathom contour of most of the southern continents is supported by geological and geophysical data.

The Fit of the Southern Continents

Rainfall patterns and the distribution of coals and evaporites in the Mesozoic and Cenozoic

Abstract The Tasmanides of eastern Australia record the break-up of Rodinia, followed by the growth of orogenic belts along the eastern margin of Gondwana. Spatially, the Tasmanides comprise five orogenic belts, with an internal Permian-Triassic rift-foreland basin system. Temporally, the Tasmanides comprise three (super)cycles, each encompassing relatively long periods of sedimentation and igneous activity, terminated by short deformational events. The Neoproterozoic-earliest Ordovician Delamerian cycle began by rifting, followed by convergent margin tectonism and accretion of island-arc forearc crust and ?island arcs in the Middle-Late Cambrian. The Ordovician-Carboniferous convergent margin Lachlan supercycle consists of three separate cycles, each ending in major deformation. The Ordovician Benambran cycle includes convergent (island-arc) and transform margin activity terminated by terrane accretion in the latest Ordovician-earliest Silurian. The Silurian-Middle Devonian Tabberabberan cycle reflects development of a large back-arc basin system, marked by rift basins and granite batholiths, behind intra-oceanic arcs and an Ordovician-Early Devonian terrane that were accreted in the Middle Devonian. The Middle Devonian to Carboniferous Kanimblan cycle began by rifting, followed by continental sedimentation inboard of a major convergent margin system that forms the early part of the Late Devonian-Traissic Hunter-Bowen supercycle. This supercycle comprises a Late Devonian-Carboniferous continental arc, forearc basin and outboard accreted terranes and subduction complexes intruded by the roots of a Permian-Triassic continental margin arc. Complex deformation ended with accretion of an intra-oceanic arc in the Early Triassic. Key features of the Tasmanides are: continuity of cycles across and along its length, precluding growth by simple eastwards accretion; development of a segmented plate margin in the Late Cambrian, reflected by major rollback of the proto-Pacific plate opposite the southern part of the Tasmanides; rifting of parts of the Delamerian margin oceanwards, to form substrate to outboard parts of the Tasmanides; the presence of five major Ordovician terranes in the Lachlan Orogen; and the generation of deformations either by the accretion of arcs, the largely orogen-parallel ‘transpressive’ accretion of Ordovician turbidite terranes (in the Lachlan Orogen), or by changes in plate coupling.

The Tasmanides of eastern Australia

While the paramount importance of global sea-level changes has been widely accepted by Quaternary geologists throughout this century, it is only within the last decade that such changes in the rest of the Phanerozoic have received much attention. There are two principal reasons for this arousal of interest. First, increased exploration of the stratigraphic record across the Earth, both on land and under the sea, and significant improvement in biostratigraphic correlation have drawn attention to what appear to have been globally synchronous events. Second, oceanographic research has demonstrated the importance of tectonically controlled changes in the cubic capacity of the ocean basins, notably variations in ridge volume, which provide a ready mechanism for sea-level changes even at nonglacial times. The adjective eustatic was first proposed for global changes of sea level by Suess ( 1906) in his great treatise The Face of the Earth. (The corresponding noun is eustasy, not eustacy as it is commonly misspelt ; the unconvinced reader need only think of ecstasy.) Eustatic sea-level changes can be inferred, as Suess recognized, by (a) plotting the temporal spread of marine sediments over the continents and (b) estimating the depositional depth variations in marine stratal sequences, which can be correlated across and between continents. To these methods can be added seismic stratigraphy, in which biostratigraphically age-determined seismic sequences on the con­ tinental margins are analyzed in terms of cycles of coastal onlap and offiap. When the results of these methods are broadly in accord, confidence in a eustatic interpretation is increased, but the range of confidence can vary considerably. It is widely accepted that there was an exceptionally high sea

K. A. W. Crook

Papers

The Geological Evolution of Australia & New Zealand

Manual of sedimentary structures

Security for australia