Abstract The Ross Sea contains three major depocenters, each underlain by a sediment-filled rift graben and an overlying glacial sedimentary sequence. The sedimentary sections are up to 14 km thick with up to 8 km in the rift grabens and up to 6 km in the presumed-glacial sequences. The rift grabens were downfaulted and filled probably during the late Mesozoic to early Cenozoic continental breakup of Gondwana; their early history may be analogous to coeval rift basins of southeast Australia, Tasmania, and New Zealand. The rift-graben sediments are unconformably overlain by glacial-marine sequences deposited since middle Eocene(?) to early Oligocene time. Renewed down-faulting has occurred along the west and east margins of the Ross Sea probably since Eocene time. The hydrocarbon potential of the Ross Sea is poorly known because only post-Eocene glacial rocks have been sampled offshore. The age and type of rocks filling the rift grabens, below the glacial sequence, is unknown. Source beds do not occur in the glacial sequence, but may exist in the rift grabens. Structural and stratigraphic traps are likely near basement structures and unconformities, which are common, and near large sedimentary structures found only in the Victoria Land Basin and along margins of the Eastern Basin. Reservoir rocks are unknown but sands could occur throughout the glacial and rift sequences. Lopatin-Waples models indicate that hydrocarbons could be generated presently at depths of 2.5 to 4.0 km, if source beds exist. Migration is likely in dipping strata along rift-graben flanks and in late-rift fault zones of the Terror Rift. Hydrocarbon seeps and accumulations are unknown in the Ross Sea. The preglacial strata that are deeply buried within the early- rift grabens have the best hydrocarbon potential; however, a definitive assessment awaits sampling of these deep,rift deposits.

Abstract Each wireline log records the properties of rocks that are ordered with respect to age. Unless the succession is inverted or faulted, depth values are a monotonic function of time, and so, log measurements are examples of time series. However, there are some important distinctions between logs and conventional time series. The results of standard mathematical methods should be interpreted thoughtfully, in a way that takes account of the true nature of the rock record of time. Patterns and trends may be revealed as systematic functions of depth. However, the depth scale should be recognized as both a nonlinear and highly discontinuous representation of time. Variable sedimentation rates and the differing compactional characteristics of lithologies are nonlinear in their effects on time-thickness relationships. Possibly more important is the fact that typical successions are riddled with discontinuities, caused by breaks in sedimentation and erosional events. These discontinuities result in the generation of multiple gaps in the time record to the extent that Ager (1973) suggested that the gaps were the dominant feature. He likened sedimentation to the life of the soldier: long periods of boredom, punctuated by short intervals of terror. The processing of logs by techniques of conventional time series analysis must therefore be interpreted in the light of appropriate concepts of sedimentation and erosion. The task has been made easier by recent research which has greatly improved our understanding of relationships between sedimentation and time. These newer concepts have their origin in results from seismic stratigraphy and sequence stratigraphy.