Application of sequence stratigraphy to seismic reflection profiles from the Bransfield Basin indicates that this modern back-arc basin formed in response to cessation of subduction at the South Shetland trench at 4 Ma. Two distinct systems tracts stack to form depositional sequences; hemipelagic sediments drape the basin during highstand/interglacial periods, whereas glacially-eroded sediments prograde into the basin during lowstand/glacial maxima. Relative ages of back-arc and forearc sequences suggest that forearc subsidence due to subduction cessation predated back-arc rifting. Since glacial fluctuations in the region are controlled primarily by sea level, the Bransfield Basin sequences may correlate with global eustatic cycles; subsidence rates and sediment thicknesses suggest that they are of $\sim$0.8 Ma duration. If so, the forearc started subsiding by 3.1 Ma, a rifted back-arc margin existed by 2.4 Ma, and basin floor volcanism began before 1.6 Ma. Tectonic segmentation of the back-arc reflects the continuing influence of the formerly active South Shetland subduction zone.

Clastic packages studied in the southern East Pisco Basin represent the transgressive Late Eocene to earliest Oligocene Paracas Group, with questionable presence of the latest Oligocene to Early Miocene Chilcatay formation. Syndepositional faulting and rugged topography protected Late Eocene sediment from direct wave attack. Fluvial systems were poorly developed in this arid environment, where sediment gravity flows provided poorly sorted sediment to fan deltas in proximal and inner shelf areas. Shelf facies contain evidence of storm-dominated sand transport and variable rates of bioturbation and suspended sediment input. In conjunction with compositional increases in igneous derived sediment, the preservation of wave induced structures increased between Paleogene and Neogene time. Factors associated with these changes include higher rates of transgression and lower sediment supply during the Late Eocene, less protected depositional areas, arid climates, and a dramatic increase in the supply of sand-sized volcanic sediment in Neogene time.

This study documents the evolution of the low sediment-supply Trinity-Sabine incised valley system during the last eustatic fall and rise. Two high sediment supply fluvial-deltaic systems, the Western Louisiana and the Brazos, acted together with the Trinity-Sabine system to produce a unique distribution of facies in the study area. Nine seismic facies were recognized using high-resolution seismic data, boring descriptions and core samples. Sequence stratigraphic techniques were used to identify major surfaces and sedimentary packages. Five phases of evolution occurred, from the last glacial eustatic highstand to the Holocene transgression. The interplay of tectonics, eustasy and sediment supply produced sedimentary bodies with a variety of internal and external configurations. High-resolution seismic data images the complexity of the deposits, in contrast to conventional seismic data. High resolution seismic data, in conjunction with cores, constitutes a powerful tool for unravelling the stratigraphic history of the study area and for testing stratigraphic models.

The Endicott Mountains allochthon is an east-west striking stack of north-northwest vergent thrust sheets which were emplaced during late Mesozoic and Cenozoic (Brookian) orogenesis. Thrust sheets in the allochthon are composed of clastic and carbonate rocks which track the progressive evolution of a Late Devonian and Early Carboniferous continental margin. Sedimentary facies in lower Upper Devonian rocks of the Beaucoup Formation delimit a volcanically active depositional basin. Volcaniclastic sediments within the Beaucoup were apparently derived from the south; whereas siliciclastic sediments were derived from the north. By the late Late Devonian, the Beaucoup depositional basin had developed into a south-facing continental margin. Southwestward progradation of the Kanayut-Hunt Fork delta system deposited thick conglomerates, sandstones, and shales on the margin and created a lithofacies pattern in which the Kanayut Conglomerate is thicker in the north and the Hunt Fork Shale is thicker in the south. Transgression of the Lower Mississippian Kayak Shale over the Kanayut Conglomerate occurred as sea level rose during the Early Mississippian. Subsequent transgressive-regressive cycles in carbonates of the Lisburne Group indicate that the margin had evolved into a stable passive margin by the middle Mississippian. The style of Brookian structures in the Endicott Mountains allochthon changes from imbricate thrust sheets and large single-phase folds in the north to a thick, variably strained thrust nappe in the south. Strain variation in the southern nappe is evidenced by a progressive change from single-phase folds at the top of the nappe to polyphase folds at the bottom. First phase fold axes change from strike-parallel at the top of the nappe to dip-parallel at the bottom, and the angle between first phase axial planes and the basal thrust decreases with depth. The change from thrust imbrication in the north to heterogeneous intranappe strain in the south apparently was controlled by the distribution of sedimentary facies and the extent of tectonic burial. The greater thickness of Kanayut Conglomerate and lack of a superjacent thrust sheet favored thrust imbrication in the north; whereas the greater proportion of shale and tectonic burial beneath the Skajit allochthon favored heterogeneous intranappe deformation in the south. Changes in fold orientation, the number of superposed fold phases, and measured strain in the southern nappe indicate that deformation was facilitated by a combination of layer parallel shortening and simple shear in a collapsing shear zone.

Seismic, surface, and well data from the mid-Adriatic Sea and the Umbria-Marche region of central Italy suggest a shallowly detached decollement thrust geometry for the central Apennines and its foreland basin with a substantial amount of shortening. The front of the Apennine overthrust system trends NW-SE in the Adriatic Sea. Palinspastically restored balanced cross sections suggest that shortening and the number of thrust sheets increase significantly from north to south. Much of the increased shortening is due to three north-south trending duplex structures in the foreland basin, which lose their identity to the north. Paleozoic basement does not appear to be involved in the thrusting east of the Tevere River, and the Triassic evaporites act as the principal detachment surface. Seismic profiles in the Umbria-Marche region do not permit the identification of the basement. However, magnetic and gravimetric interpretations indicate that the basement dips gently westward beneath the central Apennines to depths of 12-14 kms near the Tevere River. Onlap relationships in the Adriatic Sea suggest that thrust structures were formed predominantly in the middle Pliocene, with additional growth in the upper Pliocene. The Pleistocene shows no folding. The structures in the western foreland seem to have been formed in the later part of the lower Pliocene. The youngest rocks beneath the Sibillini thrust are of middle Messinian age, and thrusting gets progressively older to the west. Normal faulting occurred shortly after thrusting, and a later extensional phase continues in the Present. A Jurassic extensional event probably was dominated by moderate to low angle, east dipping normal faults, with high angle antithetic faults. Tertiary thrusting inverted some of the Jurassic extensional structures, apparently taking advantage of pre-existing discontinuities in the Triassic evaporites. In the Sibillini mountains, modern normal faults listrically sole into the pre-existing thrust detachment surface, and do not cut the (footwall) sediments of the Laga Basin. The Miocene-Pliocene clastic sequence is often detached from the Jurassic to Early Tertiary carbonate sections, and thus the structural style of shallow units in the foreland seems more complicated than deeper or more westerly units. Prominent reflections on a seismic profile are not offset by surface lineaments identified in Landsat Thematic Mapper data.

Deep structural levels of the Brooks Range thrust belt, and a unique sequence of lower Paleozoic rocks (informally named the Apoon assemblage) are exposed in a structural high near Mount Doonerak. Previous workers interpreted these rocks as autochthonous basement to the Brooks Range thrust belt, and correlated them with rocks of similar age in the North Slope and northeastern Brooks Range. The contact between the Apoon assemblage and the overlying Carboniferous rocks has been called an angular unconformity, with deformation in the lower Paleozoic rocks attributed to Devonian orogenesis. In this study, the Apoon assemblage is subdivided into four fault-bound lithologic units: (1) a fine-grained clastic unit (Pzp); (2) a mixed volcanic and volcaniclastic unit (Pzv); (3) a coarse clastic unit (Pzc); and (4) a pyroclastic volcanic unit (Pza). The rocks in the Doonerak Window contain three phases of folds: an early isoclinal phase overprinted by two less intense folding events. The last two phases of folds are parallel in the Apoon assemblage and the overlying Carboniferous rocks. The first phase of folds, however, is usually discordant. This discordance, and other data, suggest that the contact between the two units is a fault, not an angular unconformity. All three folding phases are probably related to Brookian deformation. A duplex model is proposed to explain the geometry of the structural high. The lack of Devonian structures within the Apoon assemblage affects correlation with other lower Paleozoic rocks in northern Alaska. The North Slope and northeastern Brooks Range show evidence of Devonian deformation, and hence, have a different structural history than the Apoon assemblage. The lithologies (especially volcanics) are also different in these area. The Apoon assemblage seems more closely related to lower Paleozoic rocks of the Skajit and Rosie Creek allochthons which contain related lithologies and show no evidence of Devonian deformation.

Piston core, drill core, and high resolution seismic data from McMurdo Sound were analyzed and tied to litho- and seismic stratigraphic events in the Ross Sea. The data show that the first extensive ice sheet grounding event occurred in the Ross Sea as early as late Oligocene time. Development of the East Antarctic ice sheet, and Oligocene ice sheet grounding may have been triggered by the opening of a seaway between Antarctica and Australia during late Cretaceous/early Paleogene time. As the seaway formed, moist air was advected over the cold Antarctic continental landmass. This led to increased precipitation on Antarctica and to the development of an Antarctic ice sheet by at least late Eocene time. Marine-based ice sheets appear to have waxed and waned on the Ross sea continental shelf since the Oligocene grounding event. These waxing and waning events are thought to be responsible for the development of a global Neogene stratigraphic signature. Stratigraphic analysis of seismic and drill core data from the Ross Sea suggests that the stratal geometry and thickness of glacial marine deposits is strongly controlled by the rate of glacial waxing and waning and the availability of accommodation space which in this instance is largely controlled by basin subsidence. Thick offlapping sequences form when the accommodation is high and glacial fluctuation rates are low, and thin flat-lying sequences are deposited when accommodation is low and glacial fluctuation rates are high. A new statistical technique was devised in order to analyze the complex facies relationships that are found in the stratigraphy of McMurdo Sound. Generally, these analyses show that infilling of the basin has been asymmetric. Volcaniclastic debris dominates the eastern portion of the Sound, while deposition of biogenic, ice-rafted and eolian transported debris, and basal till (during glacial maxima) infills the western Sound and central basin. During temperate interglacial events, meltwater transported debris may play an important role in infilling the Sound. Sedimentation on the volcaniclastic apron of the eastern slope of McMurdo Sound is dissimilar to most submarine fans. It is characterized by a reversal in the distribution of proximal and distal facies.

The structural styles of the Neogene basins in Southern Turkey formed in two stages. (1) Early to Middle Miocene transtension in a NNW-SSE direction disrupting the Paleozoic--Mesozoic substratum in the Adana Basin and the allochthonous ophiolite basement in the Iskenderun Basin. (2) Late Messinian-Pliocene transpression in a NW-SE direction which yielded structures on two levels. Inversions of former extensional faults sole in the substratum. The compression also shows advancing thrusts which utilize the Messinian evaporites as a decollement surface. Synchronously with regional shortening gravitational tectonics sloping towards the deeper parts of the Iskenderun Basin accompany the overall deformation. The study area and the Amik Basin to the southeast is a strain transfer system between two major sinistral transform faults; the Ecemis fault to the northwest of the Adana Basin and the Dead Sea fault to the southeast of the Iskenderun Basin, where it loses its transcurrent character into the graben zone of the Amik Basin.

The Skajit allochthon consists of an imbricated sequence of heterogeneous Devonian and lower Paleozoic clastic and carbonate rocks which structurally overly the Endicott Mountains allochthon and the Schist belt in the central Brooks Range, Alaska. Three sets of Brookian folds, north directed thrust faults, and a late set of high-angle faults were identified. Many previously undated imbricates within the Skajit allochthon, which were previously thought to be dominantly Devonian(?) in age, are largely or partially of lower Paleozoic age. Substantial lithologic differences preclude any simple correlation of the lower Paleozoic rocks of the Jesse klippe, as proposed by Brosge and Patton (1982), with rocks in the Doonerak window. The large scale involvement of lower Paleozoic rocks in Brookian thrusting favors large thrust displacements and high shortening reconstructions. A partial balanced cross section of the Skajit allochthon yields a minimum 100 km of shortening by internal imbrication.

Piston cores and Precision Depth Recorder (PDR) data collected from the western margin of the Northern Antarctic Peninsula were examined to reconstruct the late Wisconsinian glacial setting of this region and characterize the Holocene depositional setting. Evidence of subglacial scouring is restricted to the inner continental shelf, with the exception of the Adelaide-Biscoe Trough whose bed is scoured partially onto the outer shelf. Basal Tills were sampled on the inner shelf and from the Adelaide-Biscoe Trough. Transitional Glacial Marine sediments occur mostly in Marguerite Bay; whereas, modern diatomaceous muds occur almost directly on top of basal till in the Adelaide-Biscoe Trough. Terrigenous gravelly muds dominate the outer continental shelf. Petrogenic variability, pebble shape analyses and oxygen isotope data indicate that these sediments were deposited during the Holocene by icebergs. This glacial reconstruction places grounded ice in Marguerite Bay and the Adelaide-Biscoe Trough. Glacial ice retreated rapidly from the northern regions, while offshore of Marguerite Bay, an ice tongue slowly retreated. $\sp{14}$C data indicate that an ice shelf in Marguerite Bay retreated after 12,430 ybp.