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The theorem proving system Tps provides support for constructing proofs using a mix of automation and user interaction, and for manipulating and inspecting proofs. Its library facilities allow the user to store and organize work. Mathematical theorems can be expressed very naturally in Tps using higher-order logic. A number of proof representations are available in Tps , so proofs can be inspected from various perspectives.

Many Deep Sea Drilling Project drillholes in circum-Antarctic regions penetrated a basal euxinic claystone facies. The facies is dark-coloured, organic carbon and pyrite-rich, very sparsely fossiliferous, massive to burrow-mottled detrital claystone and silty claystone. At some sites redeposited silt and sand is intercalated with the facies. The facies accumulated relatively rapidly, under stagnant or restricted circulation bottom conditions. On subsided fragments of continental crust (Falkland Plateau, Campbell Plateau) the euxinic claystone facies succeeds transgressive non-marine to marine sequences; in near-continent positions it overlies the oldest oceanic crust. The former relationship appears to mark the rifting phase and the latter the early spreading phase of ocean basin development in circum-Antarctic and other Southern Hemisphere regions. Persistent oceanic biogenic sediment eventually succeeds the claystone facies at each drillsite. In the younger parts of an ocean basin biogenic sediment lies directly on oceanic crust. The change from claystone to biogenic sediment occurs earliest in first-formed oceanic basins and latest in young basins. The change appears to mark the moment when each basin had grown to sufficient size through sea-floor spreading for a thermohaline circulation to develop.

The late Cambrian Bowers Group is regressive marine to non-marine. On the basis of associations of textures and sedimentary structures (both primary and biotic), and of palaeocurrent measurements, the sediments of the newly defined Mariner Formation appear to have accumulated on a platform or continental shelf of low gradient and narrow tidal range. Trilobite- and brachiopod-bearing fissile mudstone with sparse channels and scattered stratified sandstone (open marine) is succeeded by wavy-bedded and lenticular-bedded mudstone, muddy sandstone, and rippled sandstone with bands rich in brachiopods (shallow open marine), then mudstone and laminated sandstone with lenticular bodies of oosparite (open marine shoals and protected inner shelf), and red and green, ripple- and parallel-laminated sandstone, interbedded with burrowed muddy sandstone and mudstone, with lenticular bedding (tidal flat). The sharply overlying Camp Ridge Quartzite of cross-bedded sandstone, pebbly sandstone, and sandy pebble conglomerate, is regarded as braided channel alluvium. The detritus appears to have been derived from veined low-grade metamorphic rocks and fine-grained detrital sedimentary rocks that lay south of the area.