Southeasternmost Baffin Island is mantled by Hudson Strait drift; it contains abundant limestone erratics and 20 to 50% carbonate in the matrix. To the northwest, it is replaced by drift dominated by locally derived rock of the Canadian Shield. The sense and orientation of ice-erosional features demonstrate that Hudson Strait drift is associated with northeasterly ice flow that crossed the tip of Meta Incognita Peninsula; local drift, associated with ice flow S10°W along the Hudson Strait coast, was derived from a dispersal center on the peninsula. Erratic lithologies contained in the Hudson Strait drift indicate a Labradorean provenance. Large-scale bedrock molding and the distribution of cirques indicate NE-flowing ice has been dominant throughout the middle and late Quaternary. Radiocarbon dates of in situ shells confirm that deglaciation began more than 11,000 yr ago, with the Frobisher Bay coast becoming ice free by 9300 yr ago. Five dates from Hudson Strait suggest that the strait was deglaciated before 9000 yr BP. However, ice from the Labradorean Sector recrossed Hudson Strait during the Cockburn Substage, about 8500 yr ago, damming drainage from the west. Final retreat of Labradorean ice from Baffin Island was complete by 8000 yr ago, at which time the sea was able to penetrate Hudson Bay.

High latitude intracontinental seaways occupy great troughs carved by broad tongues of inland ice as it debouched to deep marine water. Such troughs occur in glaciated coasts, but not in stable, nonglaciated ones. Where ice flowed along the walls of troughs whose adjacent uplands held local glaciers, the walls simulate alpine troughs with faceted spurs and submarine hanging tributary valleys. Where uplands were not glaciated, trough walls are unbreached. Where ice flowed across them, coasts are digitate in low relief. In the northeastern sector of the Laurentide Ice Sheet, large glacial grooves converge toward the Gulf of Boothia-Prince Regent Inlet-Lancaster Sound avenue of egress to open sea, suggesting that it was an exit for inland ice which shaped it to its present form. The subduction Pacific coast of the Americas is mostly harborless in nonglaciated latitudes, but in southern Chile and British Columbia it is dissected. A circular gravity high 2800 km across is concentric with the area covered by the Laurentide Ice Sheet. Abyssal glacial silts are voluminous enough to account for an average of 100–150 m of erosion over the area covered by the Laurentide Ice Sheet.

We measured the offsets of six stream valleys, of 30 to 90 m, along the northwest-southeast trending, left-lateral Haiyuan strike-slip fault, in north-central China. Minimum ages of these offsets were determined to estimate lower bounds for the Holocene slip rate. The most reliable bounds are 7.6 ± 1.0 and 6.7 ± 1.0 mm/yr, with three others that are smaller (3.4 ± 0.7, 3.5 ± 0.9, and 4.1 ± 0.4 mm/yr) and one large value (16.4 ± 5.9 mm/yr) that we doubt. Thus, the average Holocene slip rate of the Haiyuan fault is larger than 6 mm/yr and probably exceeds 7 mm/yr. If the average slip rate of 5 to 10 mm/yr for the Quaternary Period is applicable to the Holocene Epoch, the average rate is 8 ± 2 mm/yr.

An extended chronology of Lahontan basin lake levels based on uranium-series age estimates correlates with the global ice-volume record. Lake highstands occur at or shortly after times of maximum ice-sheet size. Moderate size lakes occur when the global ice volume is about 80% of its maximum. The data indicate that lake levels rise and fall relative to the proximity of the mean position of the jetstream. When the continental ice sheet is above some threshold size or shape, it appears that the large-scale circulation and climatic conditions are right for producing lakes of moderate to large size within the Lahontan basin.

The isotopic composition of oxygen in freshwater calcareous tufa seems to be a sensitive indicator of past climatic changes. Results of measurements of δc18O and δc13C in tufa samples dated with the 14C method are used to reconstruct Holocene climatic changes in southern Poland. Values of δc18O obtained on tufa samples from four sites (Raclawka, Rzerzuŝnia, Trzebienice, Sieradowice) representing different hydrodynamic conditions of tufa sedimentation seem to form a selfconsistent series. These values, with some simplifying assumptions concerning the course of tufa sedimentation, were therefore used to estimate mean annual temperatures in the interval ca. 9500-2000 yr B.P. When the resulting curve of thermal changes in southern Poland is compared with changes of deposition and erosion of tuffaceous sediments and with results of other methods of reconstruction of paleoclimate in central Europe, a reasonable agreement among the different specific methods is seen.

Three lithologically distinct alluvial units of Holocene age can be distinguished along trenched cross sections of the Missisquoi valley bottom. The oldest is of early Holocene age, and the associated floodplain had aggraded to nearly its present level by 8000 14C yr B.P. At that time, early Archaic projectile points were deposited in a fire hearth 50 cm below the surface. Abandonment of this floodplain was followed by the development of an A-E-Bt soil profile. Accumulation of a younger floodplain had begun by 6400 14C yr B.P. and local sedimentation persisted to ca. 500 14C yr B.P., as indicated by radiocarbon dates of buried woody debris (including large logs) and of charcoal. Alluvium of the modern floodplain began accreting after A.D. 1860 and contains machine-cut square nails, whiteware ceramics, and coal clinker. Previous locations of the river channel can be reconstructed from relict surfaces marked by paleosols, the preserved depositional stratigraphy, and the radiocarbon samples. Immediately after regression of the Champlain Sea from this part of the valley, and before 8000 14C yr B.P., the river incised late Fleistocene marine silts and clays at an average rate of at least 1 m/100 yr. After the interval of downcutting, episodic lateral migration became the dominant process, with the rate varying between 0 and 4 m/100 yr. The early Holocene incision was most likely a lagged response to postglacial crustal rebound, whereas strong soil development and floodplain stability between 8000 and 6400 14C yr B.P. may reflect an independently documented warmer, and perhaps drier, climate in New England at this time. Finally, the post-A.D. 1860 period of active floodplain sedimentation may have been a response to timber clear-cutting, row crop agriculture, and cattle and sheep grazing in the watershed.

An unusually well-defined association between guano-derived phosphate rock (apatite) and coral carbonates on Pelsaert Island has provided an opportunity to test uranium-series dating methods as applied to insular phosphorites. The phosphate deposit, which is bracketed by late Pleistocene and Holocene corals with 230Th/234U ages of 120,000 and 4700 yr B.P., respectively, has 230Th/234U ages ranging from 85,000 to 112,000 yr B.P. The mutually consistent results suggest that phosphate deposition commenced soon after the peak of the last interglaciation and has been largely controlled by sea-level fluctuations and probably other factors associated with late Quaternary climate in this area.

Dendroecological analysis of black spruces (Picea mariana (Mill.) BSP.) near the shore of Clearwater Lake in the eastern Canadian subarctic yielded information on water level over the past three centuries. Tree positions, growth froms, layering, tree ring patterns, and ice scars provide direct evidence of a major rise in lake level. From the 17th century to the present, trees on the lake shore were progressively submerged by the increasing water level, which reached a maximum in this century. Higher levels began around the mid-18th century when shoreline spruce trees started to lean because extensive wave erosion caused landward shore displacement. High mortality of leaning spruce and abundant ice scar formation occurred during this century. The rise in water level in inferred to have been caused by snowier winters occurring parallel to climatic warming.

Five seasons of excavation in Feature Area 2-1 of the Lubbock Lake Landmark, Texas, exposed a megafaunal bone accumulation in sands and gravels deposited by a late Pleistocene meandering stream. Many bone specimens exhibit evidence of alteration, supporting interpretation of the feature as an in situ, secondary meat-processing area; the gravels are interpreted as the point bar of a meandering stream. Faunal remains lying stratigraphically above the point bar have been considered to form a separate, noncultural feature produced by stream flooding. However, rose diagrams and analysis of adjusted residuals demonstrate that a statistically significant amount of bone in each feature is aligned along axes of preferred orientation. Further, the orientation patterns and statistical analyses of both features exhibit the same trends, suggesting that the same processes affected both. Although the evidence does not rule out a role of human behavior, it does demonstrate that stream currents significantly influenced feature structure.