A bog pond 4 km east of Yellowstone Lake has a pollen record starting with an Artemisia spruce assemblage, implying alpine vegetation. A layer of volcanic ash, dated as 14,360 ± 400 BP (probably Glacier Peak or Mt. St. Helens J), occurs within the zone, which terminates at 11,630 ± 180 BP. The rest of the pollen sequence is dominated by lodgepole pine, with reappearance of spruce pollen in modest quantities about 4500 BP, according to dating provided by a layer of Mt. Mazama ash (6600 BP). The present vegetation of the area is marked by forests of lodgepole pine with some stands of spruce and fir. The pollen sequence suggests that the upper treeline before 11,600 y. a. was perhaps 500 m lower than today. The climate then became warmer and/or drier than today (Altithermal interval). About 4500 y. a., a slight climatic reversal took place, roughly contemporaneous with the regrowth of glaciers in the western mountains (neoglaciation).

The palynology of stratigraphic sections from road-cut and gravel-pit exposures and from a fen and sphagnum bogs in the southern part of the Chilean lake district (40° 53′ S, 72°37′ W-41°24′ S, 72°53′ W) is the basis for interpreting vegetation and climate during the last interglaciation and glaciation (named Llanquihue Glaciation) and during the post-glacial. To help interpretation, modern pollen rain was studied in relation to vegetation and altitude along a transect on the west slope of the Andes, and average January (summer) temperatures were interpreted. The upper limit of closed Andean forest, where wind is a determinant, appears to be close to the 12°C January isotherm; parkland in southern Chile does not exceed the January isotherm of 9°C.

Grassland and later southern beech forest are evident during the interglaciation that is dated at more than 39,900 radiocarbon yr. Climate of the grassland was relatively dry; during the forest phase, it was wet, cool, and approximately the same as at present. During Llanquihue Glaciation, average January temperature is estimated to have been about 8°C colder than today at 19,450 BP, some 5° colder shortly before 36,300 BP, and around 4° colder at 10,000 BP. Antarctic-alpine tundra or parkland, under colder, drier climate, is mostly in evidence in the vicinity of the study sites before about 12,000 BP. During the postglacial, forest communities occupied the lake district, and temperatures there were probably 1–2°C above (by 6500 BP) and as much as 2° below (4500-0 BP) the present-day average of about 16°.

This pattern of climatic changes finds accord, in general terms, in other parts of the Southern Hemisphere where palynological, chronological, and glacial geological studies are reported. Postulated as a cause of these changes are shifts in the intensity of air mass circulation in antarctic latitudes.

In midwestern United States the most important widespread environmental event during the Holocene about 8000 y.a. was the establishment of an effective precipitation pattern that in part defines the Prairie Peninsula. The pattern occupies a region that is dominated by dry westerly air for 6–9 mo during normal years and for 9–12 mo during drought years. Regional soil geography correlates readily with zones of precipitation effectiveness with Brunizem (Udolls) conforming to the moist, subhumid zone, Chernozem (Boralls, Udolls) relating to the dry, subhumid zone, and Chestnut and Brown soils (Ustolls) fitting the semiarid zone. During the past few thousand years, a climatic reversal has caused encroachment of forest on prairie resulting in the formation of transitional or intergrade soils.

In local areas the Holocene is expressed on the land surface by the soil geomorphic unit which is the repetitive occurrence of a sequence of soils on the erosional surface of a hillslope and on the correlative depositional body at the foot and toe of the slope. This unit embraces time, lithology, landscape, and soils and provides a means for mapping the Holocene on the countryside.

Shoreline changes since 1776, including two 30-yr periods separated by nearly 100 yr are documented from surveys, topographic maps, harbor charts, and aerial photographs for the southeastern corner of the island of Martha's Vineyard, Massachusetts (41°25′ N, 70°35′ W). From 1776 to 1969, a barrier beach has receded by more than 880 m, and average rate of 4.6 m/yr. A series of four detailed surveys from 1840 to 1886 document consistent shoreline retreat in this area of 3.1 m/yr.

For the period 1938–1969, planimetry from aerial photographs and field observation indicate that more than 28 ha and nearly 3 × 106 m3 of foreland composed of till have washed away. A house, located 200 m from the cliff edge of the foreland in 1938 was only 56 m from the cliff edge in July 1972.

Violent storms were associated with the opening of the bay behind the barrier beach in nearly the same location in 1856, 1886, 1938, and 1954. Easterly migration of the opening results in rapid erosion of the southeastern corner of the island (Wasque Point) and eventual closing of the opening.

Field observation of the 1954 opening indicates that the mechanism of failure of the barrier beach is primarily by storm tide-induced subsidence. Subsequently, strong (up to 1.2 mps) easterly currents cause migration of the opening to the east and closure within 15 yr.

A summary review of evidence for changes in sea level in the past is suggested in partial explanation for the consistent shoreline retreat described in this paper.

A zone of synchronous end moraines has been recognized in the Lake Superior region across northern Ontario and Michigan. The moraines were formed between 11,000 and 10,100 y.a. as cold climate resulted in successive halts in the general ice retreat. The cold climate is also indicated by the presence of tundra near Lake Superior until about 10,000 y.a. This episode is here referred to as the Algonquin Stadial. It was preceded and followed by rapid deglaciation. The Algonquin Stadial is comparable in age with the Younger Dryas Stadial of Europe, and indicates a reversal in the continuous trend toward a warmer climate during Late-Wisconsin (an) time. The apparent conflict between the present result (based on geologic evidence) and earlier pollen stratigraphical studies with no reversal is discussed.

Glacial Lake Duluth formed in the western Lake Superior basin before 11,000 BP, followed by a series of Post-Duluth lakes between approximately 11,000 and over 10,100 BP. The Main Lake Algonquin stage in the Huron and Michigan basins terminated approximately 11,000 BP. The subsequent high-level post-Main Algonquin lakes, which were contemporaneous with the Post-Duluth lakes, existed in the southeastern Lake Superior basin. When the ice margin was along the north shore 9500 BP Lake Minong occupied the whole Lake Superior basin. By 9000 BP the ice had retreated north of Lake Superior-Hudson Bay divide.

Emerged coral reef terraces on the Huon Peninsula in New Guinea were reported in a reconnaissance dating study by Veeh and Chappell 1970. Age definition achieved was not good for several important terraces, and we report here a series of new 230Th/234U dates, which further clarify the history of late Quaternary eustatic sea level fluctuations. More than 20 reef complexes are present, ranging well beyond 250,000 yr old: we are concerned with the seven lowest complexes. Major reef-building episodes dated by 30Th/234U are reef complex I at 5–9 ka (kilo anno = 1000 yr), r.c. IIIb at 41 ka (four dates), r.c. IV at 61 ka (four dates), r.c. V at 85 ka (two dates), r.c. VI at 107 ka (two dates), and r.c. VII at 118–142 ka. Complex II was previously dated by 14C at 29 ka: this age has not yet been confirmed, and may be only a lower limit. The reef crests were built during or immediately before intervals of sea level maxima, when rates of rising sea level and tectonic uplift briefly coincided. The culmination of each reef-building episode was only a few thousand years in duration, and multiple dates from the same reef complex generally group within the statistical errors of the individual dates.

Several methods can be used to estimate the altitude of each sea level maximum relative to present sea level. The least complicated is to calculate mean tectonic uplift rate for each profile of the terraces, and use the mean rate to calculate the tectonic displacement of each dated reef complex on that profile. The difference between the present altitude of a reef complex and its calculated tectonic uplift gives the paleosea level at the time the reef grew. We estimate uplift rates for six surveyed sections by calibrating against published paleosea level estimates from Barbados and elsewhere, viz 125 ka, paleosea at +6 m; 103 ka, −15 m; 82 ka, −13 m. For each section the individual uplift rates for reefs V, VI, and VIIb are within 5% of their section means. Using the mean rates. paleosea level estimates for reef crests II, IIIB, and IV are made for each section. Consistency of estimates between sections is good, giving −28 m for the 60 ka paleosea level, around −38 m for the 42 ka level and −41 m for the 28 ka level (if the age is older the paleosea level would be lower. Using the mean uplift rates, the 82 ka and 103 ka paleosea levels are also estimated for each section: all individual estimates are plotted graphically, and a sea level curve drawn. The reef stratigraphy indicates sea level lowerings between each dated reef crest: the crests probably represent the interstadials of the Wisconsin (Würm, Weichsel) Glaciation, and intervening lower levels correspond to stadials. Since the last time of eustatic sea level higher than the present (about 125 ka), five sea level maxima occurred at roughly 20-ka intervals, none being as high as the present.

Four paleosols, and soil horizons within paleosols, were clearly identified in the thick calcium carbonate-free loess sections at Timaru, South Island, New Zealand, by changes in the distribution of total phosphorus and calcium phosphate in the upper 2 m to each paleosol. Extractable manganese was also sensitive in identifying paleosols, particularly the upper horizons. The distribution of bulk density values was useful in identifying paleosols; however, the maximum bulk density (>1.7 g/cc) occurred in horizons identified as B2 rather than fragipan horizons in three of four cases. The distribution of clay particles was useful in understanding the genesis of the modern soil and paleosols, but not in identifying paleosols.

The racemization rate constant for aspartic acid has been determined from the D/L isomeric ratio in four strata of radiocarbon dated woodrat midden in Arizona. Two different methods of stereospecifically deaminating L-aspartic acid prior to the assay are compared. It is found that pure L-amino acid oxidase pretreatment of the DL aspartic acid mixture requires one less step than treatment with crude, dialyzed venom (Crotalus viridis) but that the two methods give the same results. Application of the theory of amino acid racemization dating is discussed in the context of the steric properties ofthe protein environment in which the racemization actually occurs.

Late Pleistocene radiolarian assemblages were examined in two cores (V24-58 and RC11-209) from the eastern equatorial Pacific Ocean, using Nigrini's 1970 method of recurrent group analysis. The radiolarian “climatic index” curves obtained by this analysis were in close agreement with fluctuations in carbonate levels established previously for the same cores. This correspondence suggests that equatorial radiolarian assemblages changed significantly in response to Pleistocene climatic oscillations. The radiolarian “climatic indices” of the two cores showed close agreement with each other. Our data indicate that equatorial radiolarian assemblages may prove useful for regional correlations between cores, and for paleoclimatic interpretations.

Pleistocene alluvium along Little Kettle Creek in east-central Georgia contains a unique record of vertebrate life in the Appalachian Piedmont during a colder phase of the late Quaternary. The small fauna includes fishes and the following mammals: Synaptomys cooperi, the southern bog lemming; Clethrionomys sp., a redback vole; Mammut americanum, the American mastodon; a mammoth, Mammuthus sp.; Odocoileus cf. virginianus, a deer; and Bison sp. Both Synaptomys and Clethrionomys are primarily boreal genera of rodents which today reach their southern limits at higher elevations in the Great Smoky Mountains about 175 km north of the fossil locality. The American mastodon is also commonly associated with Pleistocene spruce bogs in eastern North America. Catfish (Ictalurus (?) sp.) vertebrae from the deposit show well-defined annual rings in contrast with the weakly marked annuli produced by fish living in the same area today. The total aspect of the fauna is one of considerably lower temperatures than those prevailing in the Georgia Piedmont now. The joint occurrence of bison and proboscideans indicates an age no older and no younger than late Pleistocene (Rancholabrean) for the assemblage. Because no pollen was found in the sediments and there was insufficient organic matter present for 14C dating, no more precise age can yet be assigned to the fauna.

Quaternary terraces and pediments along Ralston Creek and Clear Creek, near Golden, Colorado, are associated with Verdos, Slocum, Louviers, and Broadway Alluviums. Terrace deposits can be locally correlated on the basis of elevation and relict paleosols. The terrace sediments probably represent aggradation by braided streams flowing from glaciated drainage basins. Engineering hydraulic calculation procedures suggest that flood flows were 2–3 m deep on steep gradients (0.008–0.01). Discharges were as great as 1400 m3/sec, nearly an order of magnitude greater than modern flood discharges. The most useful paleohydraulic calculation techniques were found to be the dimensionless shear approach applied to stream competence and bedload function theory applied to stream capacity.

Examination of loess columns in coastal South Canterbury, New Zealand, and the recognition of paleosols with comparable morphology to surface soils allowed the division of the loess column into six members. The upper loess members 1–4 are grouped into a proposed Dashing Rocks Formation. This commonly overlies an erosion surface on Timaru Basalt, but in some situations is underlain by loess member 5 and mixed loess and weathered basalt member 6. The paleosol developed on loess member 5, on both morphological and chemical evidence, is indicative of a period of soil formation of longer duration or greater intensity than is indicated by the overlying paleosols or surface soils. Therefore members 5 and 6 are grouped into a separate formation.

A radiocarbon chronology for loess members 1 and 2 of the Dashing Rocks Formation, suggests loess accumulation phases from 9900 to 11,800 and prior to 31,000 radiocarbon yr BP, followed by periods of soil formation and contemporary peat development in surface depressions.

A hypothesis is presented suggesting that at least loess members 1 and 2 of the Dashing Rocks Formation accumulated during periods of glacial recession which in turn precipitated fluvial and eolian erosion, transport and redeposition of fluvioglacial deposits. The periods of soil development indicated by the paleosols were initiated during warm interstadial conditions and continued throughout the cooling of the following stadial. Such an interpretation has its parallels in the northern hemisphere but is in slight disagreement with previous glacial and fluvioglacial chronologies accepted in New Zealand.

Uranium series dates on bone from the Isimila Prehistoric Site, Tanzania, indicate that this East African Acheulian site may be older than originally estimated. They raise the possibility that the Middle Pleistocene sediments containing Acheulian occurrences span a longer range of time than had been supposed. This could add to the plausibility of a contention by Hansen and Keller that differences between artifacts in the uppermost Acheulian horizon and in lower-lying beds are primarily a reflection of change through time rather than a result of different human activities.

A summary of the artifact content and associations of the several archeological stratigraphic units is given, and, although a sort of “developmental sequence” can be seen, the existence of discrepant occurrences suggests that an interpretation of directional change as a “function of time” does not, in fact, well accommodate the evidence.

Quantitative changes in artifact class proportions in aggregates seem just as likely to be related to local exploitation potentials for early man which were produced during the process of basin in-filling, while observed qualitative differences in the lower-lying horizons may be due to samples biased because of limited exposures which are restricted to a single sedimentary environment.

The initial peopling of South America is reviewed in terms of geochronological and archaeological data. The problem is put in historical perspective and a systematic evaluation is made of the latest typologically oriented arguments for the presence of preprojectile point complexes. Field evidence is very weak for early Biface and Chopper traditions. There is better support for an early Flake tradition, but it is not likely to precede the use of stone projectile points.

Radiocarbon dates and “terrace dating” should be used only with great caution and careful attention to the nature of cultural and stratigraphic associations. Uncritical acceptance of determinations on bone and soil samples has led to extremely problematic cultural reconstructions. Emphasis on stratified sites with finished artifacts, faunal assocations, and charcoal dates leads to a reconstruction at odds with those presented in recent textbooks. It is concluded that the bulk of solid evidence favors the entry of man as a big game hunter using stone projectile points and having an adaptation much like that of the Paleo-Indians of North America.