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Here we address a long-standing puzzle of ice-age climate called the “fly in the ointment of the Milankovitch theory.” Using geomorphic mapping and 10Be surface-exposure dating, we show that five moraine belts were formed during maxima of the last ice age by the Pukaki glacier in New Zealand’s Southern Alps. They afford ages of 41.76 ± 1.09 ka, 35.50 ± 1.26 ka, 27.17 ± 0.68 ka, 20.27 ± 0.60 ka, and 18.29 ± 0.49 ka. These five maxima spanned an entire precessional cycle in summer insolation intensity at the latitude of the Southern Alps. A similar mismatch between summer insolation and glacier extent also characterized the Chilean Lake District in the mid-latitudes of South America. Thus, in apparent contrast to northern ice sheets linked by Milankovitch to summer insolation at 65°N latitude, the behavior of southern mid-latitude glaciers was not tied to local summer insolation intensity. Instead, glacier extent between 41.76 ka and 18.29 ka, as well as during the last termination, was aligned with Southern Ocean surface temperature and with atmospheric carbon dioxide.

Glacial maxima and their terminations provide key insights into inter-hemispheric climate dynamics and the coupling of atmosphere, surface and deep ocean, hydrology, and cryosphere, which is fundamental for evaluating the robustness of earth's climate in view of ongoing climate change. The Last Glacial Maximum (LGM, ∼26–19 ka ago) is widely seen as the global cold peak during the last glacial cycle, and its transition to the Holocene interglacial, dubbed 'Termination 1 (T1)', as the most dramatic climate reorganization during this interval. Climate records show that over the last 800 ka, ice ages peaked and terminated on average every 100 ka (‘100 ka world’). However, the mechanisms pacing glacial–interglacial transitions remain controversial and in particular the hemispheric manifestations and underlying orbital to regional driving forces of glacial maxima and subsequent terminations remain poorly understood.

The termination of the last ice age featured a major reconfiguration of Earthʼs climate and cryosphere, yet the underlying causes of these massive changes continue to be debated. Documenting the spatial and temporal variations of atmospheric temperature during deglaciation can help discriminate among potential drivers. Here, we present a 10Be surface-exposure chronology and glaciological reconstruction of ice recession following the Last Glacial Maximum (LGM) in the Rakaia valley, Southern Alps of New Zealand. Innermost LGM moraines at Big Ben have an age of 17,840 ± 240 yrs, whereas ice-marginal moraines or ice-molded bedrock surfaces at distances up-valley from Big Ben of 12.5 km (Lake Coleridge), ∼25 km (Castle Hill), ∼28 km (Double Hill), ∼43 km (Prospect Hill), and ∼58 km (Reischek knob) have ages of 17,020 ± 70 yrs, 17,100 ± 110 yrs, 16,960 ± 370 yrs, 16,250 ± 340 yrs, and 15,660 ± 160 yrs, respectively. These results indicate extensive recession of the Rakaia glacier, which we attribute primarily to the effects of climatic warming. In conjunction with geomorphological maps and a glaciological reconstruction for the Rakaia valley, we use our chronology to infer timing and magnitude of past atmospheric temperature changes. Compared to an overall temperature rise of ∼4.65 °C between the end of the LGM and the start of the Holocene, the glacier recession between ∼17,840 and ∼15,660 yrs ago is attributable to a net temperature increase of ∼4.0 °C (from −6.25 to −2.25 °C), accounting for ∼86% of the overall warming. Approximately 3.75 °C (∼70%) of the warming occurred between ∼17,840 and ∼16,250 yrs ago, with a further 0.75 °C (∼16%) increase between ∼16,250 and ∼15,660 yrs ago. A sustained southward shift of the Subtropical Front (STF) south of Australia between ∼17,800 and ∼16,000 yrs ago coincides with the warming over the Rakaia valley, and suggests a close link between Southern Ocean frontal boundary positions and southern mid-latitude climate. Most of the deglacial warming in the Southern Alps occurred during the early part of Heinrich Stadial 1 (HS1) of the North Atlantic region. Because the STF is associated with the position of the westerly wind belt, our findings support the concept that a southward shift of Earthʼs wind belts accompanied the early part of HS1 cooling in the North Atlantic, leading to warming and deglaciation in southern middle latitudes.

The timing and magnitude of postglacial climatic changes around the globe provide insights into the underlying drivers of natural climate change. Using geomorphologic mapping of moraines, 10 Be surface-exposure dating, snowline reconstructions, and numerical modeling, we quantified glacier behavior during Late Glacial (15–11.5 ka) and Holocene (the past ∼11.5 k.y.) time in the Ben Ohau Range, New Zealand. Glaciers were more extensive during the Antarctic Cold Reversal (ACR), than subsequently, and the margins underwent a punctuated net withdrawal over the Holocene. Numerical modeling experiments that achieve the best fit to the moraines suggest that air temperature during the ACR was between 1.8 °C and 2.6 °C cooler than today, with similar (±20%) prescribed precipitation. After the ACR, a net snowline rise of ∼100 m through the Younger Dryas stadial (12.9–11.7 ka) was succeeded by a further "long-term," or net, rise of ∼100 m between ∼11 k.y. and ∼500 yr ago. Glacier snowline records in New Zealand show generally coherent Late Glacial and Holocene climate trends. However, the paleoclimate record in the southwest Pacific region shows important differences from that in the Northern Hemisphere.

Determining whether glaciers registered the classic Last Glacial Maximum (LGM; ∼26,500–∼19,000 yrs ago) coevally between the hemispheres can help to discriminate among hypothesized drivers of ice-age climate. Here, we present a record of glacier behavior from the Southern Alps of New Zealand during the ‘local LGM’ (LLGM). We used 10 Be surface-exposure dating methods and detailed glacial geomorphologic mapping to produce a robust chronology of well-preserved terminal moraines deposited during the LLGM near Lake Ohau on central South Island. We then used a glaciological model to estimate a LLGM glacier snowline and atmospheric temperature from the Ohau glacier record. Seventy-three 10 Be surface-exposure ages place culminations of terminal moraine construction, and hence completions of glacier advances to positions outboard of present-day Lake Ohau, at 138,600 ± 10,600 yrs, 32,520 ± 970 yrs ago, 27,400 ± 1300 yrs ago, 22,510 ± 660 yrs ago, and 18,220 ± 500 yrs ago. Recessional moraines document glacier recession into the Lake Ohau trough by 17,690 ± 350 yrs ago. Exposure of an ice-molded bedrock bench located inboard of the innermost LLGM moraines by 17,380 ± 510 yrs ago indicates that the ice tongue had receded about 40% of its overall length by that time. Comparing our chronology with distances of retreat suggests that the Ohau glacier terminus receded at a mean net rate of about 77 m yr −1 and its surface lowered by 200 m between 17,690 and 17,380 yrs ago. A long-term continuation of ice retreat in the Ohau glacier catchment is implied by moraine records at the head of Irishman Stream valley, a tributary of the Ohau glacier valley. The Irishman Stream cirque glacier advanced to produce a set of Lateglacial moraines at 13,000 ± 500 yrs ago, implying that the cirque glacier was less extensive prior to that advance. We employed a glaciological model, fit to these mapped and dated LLGM moraines, to derive snowline elevations and temperature parameters from the Ohau glacier record. The modeling experiments indicate that a snowline lowering of 920 ± 50 m and temperature depression of 6.25 ± 0.5 °C below modern values allows for the Ohau glacier to grow to an equilibrium position within the LGM moraine belt. Taken together with a glaciological simulation reported from the Irishman Stream valley, snowlines and temperatures increased by at least ∼520 m and ∼3.6 °C, respectively, between ∼18,000 and ∼13,000 yrs ago. Climate parameters derived from the Ohau glacier reconstruction are similar to those derived from glacier records from Patagonia, to air temperature indicators from Antarctica, as well as to sea-surface temperature and stratification signatures of the Southern Ocean. We think that the best explanation for the observed southern LLGM is that southern winter duration modulated Southern Ocean sea ice, which in turn influenced Southern Ocean stratification and made the surface ocean cooler. Orbitally induced cooling of the Southern Ocean provides an explanation for the LLGM in the Southern Alps having been coincident with the northern LGM. We argue further that the global effect of North Atlantic stadials led to disturbance of Southern Ocean stratification, southward shifts of the subtropical front, and retreat of Southern Alps glaciers. Collapse of Southern Ocean stratification during Heinrich Stadial-1, along with attendant sea-surface warming, triggered the onset of the Last Glacial termination in the Southern Alps of New Zealand.

We present a simulation of the New Zealand Southern Alps icefield at the Last Glacial Maximum (LGM, c. 30,000–20,000 calendar years ago (ka)) in an attempt to constrain the climate of that period. We use a 500 m-resolution ice-sheet model parameterised using empirical glaciological, climatological and geological data specific to the model domain to simulate the entire Southern Alps icefield. We find that an LGM cooling of at least 6–6.5 °C is necessary to bring about valley glaciers that extend beyond the mountains. However, climate–topography thresholds related to the elevation and hypsometry of individual catchments control the gradient of the rate of glacier expansion in the domain, and in order to remain within geologically reconstructed LGM limits we find that the LGM cooling was most likely associated with a precipitation regime up to 25% drier than today. Wetter-than-present scenarios give rise to equilibrium line depressions and ice extents that are incompatible with empirical evidence. These results perhaps indicate that either the westerly air masses affecting New Zealand during the LGM were drier than today, or that they were weaker or zonally displaced with respect to present.

The geographic extent of cooling associated with the Antarctic Cold Reversal is unclear. Dating of glacial moraines in New Zealand suggests that the cooling extended into the southern mid-latitudes, possibly as a result of the northward migration of the southern subtropical front.

The Younger Dryas — a period of sudden cooling in the Northern Hemisphere about 12,900 years ago — is perhaps the best-known example of abrupt climate change. But the global extent of the Younger Dryas is a topic of intense debate, particularly in the record of glacial behaviour in New Zealand. A new reconstruction of the growth and retreat patterns of glaciers in the Southern Alps in New Zealand at the time of the Younger Dryas supports the suggestion that temperature reductions in the north caused warming and glacial retreat in the Southern Hemisphere through a series of climate feedbacks. The Younger Dryas — during which Northern Hemisphere temperatures cooled drastically in just a few years — is perhaps the best-known example of abrupt climate change, but its global extent is under debate, particularly in the record of glacial behaviour in New Zealand. These authors present evidence for glacial retreat in New Zealand during the Younger Dryas, supporting the hypothesis that Northern Hemisphere climate changes caused Southern Hemisphere warming through a series of climate feedbacks. Millennial-scale cold reversals in the high latitudes of both hemispheres interrupted the last transition from full glacial to interglacial climate conditions. The presence of the Younger Dryas stadial (∼12.9 to ∼11.7 kyr ago) is established throughout much of the Northern Hemisphere, but the global timing, nature and extent of the event are not well established. Evidence in mid to low latitudes of the Southern Hemisphere, in particular, has remained perplexing1,2,3,4,5,6. The debate has in part focused on the behaviour of mountain glaciers in New Zealand, where previous research has found equivocal evidence for the precise timing of increased or reduced ice extent1,2,3. The interhemispheric behaviour of the climate system during the Younger Dryas thus remains an open question, fundamentally limiting our ability to formulate realistic models of global climate dynamics for this time period. Here we show that New Zealand’s glaciers retreated after ∼13 kyr bp, at the onset of the Younger Dryas, and in general over the subsequent ∼1.5-kyr period. Our evidence is based on detailed landform mapping, a high-precision 10Be chronology7 and reconstruction of former ice extents and snow lines from well-preserved cirque moraines. Our late-glacial glacier chronology matches climatic trends in Antarctica, Southern Ocean behaviour and variations in atmospheric CO2. The evidence points to a distinct warming of the southern mid-latitude atmosphere during the Younger Dryas and a close coupling between New Zealand’s cryosphere and southern high-latitude climate. These findings support the hypothesis that extensive winter sea ice and curtailed meridional ocean overturning in the North Atlantic led to a strong interhemispheric thermal gradient8 during late-glacial times, in turn leading to increased upwelling and CO2 release from the Southern Ocean9, thereby triggering Southern Hemisphere warming during the northern Younger Dryas.

Vive La Différence How closely do climate changes in the Northern and Southern Hemispheres resemble each other? Much discussion has concentrated on the Holocene, the warm period of the past 11,500 years in which we now live, which represents a baseline to which contemporary climate change can be compared. Schaefer et al. (p. 622 ; see the Perspective by Balco ) present a chronology of glacial movement over the last 7000 years in New Zealand, which they compare to similar records from the Northern Hemisphere. Clear differences are observed between the histories of glaciers in the opposing hemispheres, which may be owing to regional controls. Thus, neither of two popular arguments—that the hemispheres change in-phase or that they change in an anti-phased manner—appear to be correct.

Several distinctive marginal moraines of Preboreal age have been observed in Norway. They are grouped into three major morainal zones that are radiocarbon dated at about 9900±100, 9600±100 and 9300±100 B.P. respectively. The following deglaciation of central Norway was rapid and most likely completed about 8500 B.P. Evidence of glacier fluctuations up to recent time is discussed. The results are based partly on observations by the field parties of the I.G.C.P. project ‘Quaternary Glaciations in the Northern Hemisphere’.

The age and correlation of marginal moraines in Norway is discussed. A tentative location of the ice margin 15,000 B.P. is suggested, as well as a more firmly based location of the 10,000 B.P. ice margin. The results are preliminary and based partly on observations by the field parties of the I.G.C.P. project Quaternary Glaciations in the Northern Hemisphere'.

Isoleucine epimerization (alle/Ue) ratios in the pelecypod Mya truncata and benthic foraminifer Cibicides lobalulus from emerged marine units in western Norway allow construction of a regional relative chronostratigraphy for the Ecmian and Weichselian. Two in situ interglacial sections are considered correlative by the similar biostratigraphy and alle/Ile ratios in C. lobalulus. Overlying sediments at the two sites are of both marine and glacial origin. Neither site contains a complete Weichselian record, but allelic ratios, lithostratigraphy and fauna! changes suggest at least four stadial and three interstadial events occurred along the western Norwegian coast during Early and Middle Weichselian time. Kinetic data defining the relationship between the isoleucine epimerization rate constant and temperature for the species studied allow the estimation of paleotemperatures for samples of known age. Accepting published age estimates for the Eemian interglacial beds, the average Weichselian temperature in western Norway is calculated to have been ca. 4°C below the average Holocene temperature, whereas the last interglacial was 1 to 2°C warmer that the Holocene. The limited temperature depression over this region during the Weichselian implies that coastal western Norway was ice-covered only about 30% of this period, and that Atlantic water, although not necessarily in a warm surface current as today, entered the Norwegian Sea during much of marine isotope stage 5 and intermittently during stage 3. Interpolated amino acid ages date interstadial events at ca. 94 ka, 78 ka and 52 ka, B.P., whereas glacial events are dated ca. 103 ka and bracketed by limiting dates between 78 and 89 ka, between 52 and 63 ka and less than 36 ka B.P.

On the basis of studies of many stratigraphical profiles, together with radiocarbon dates, Thorium-Uranium dates and amino-acid dates, the following preliminary stratigraphy is proposed: (1)Late Weichselian. Stavanger Stadial. The glacier covered the coast and deposited the upper drift sheet. - (2) Middle Weichselian.(a)Sandnes Interstadial (30,000?-39,000 years B.P.). Thick units of marine deposits underlie the Stavanger Stadial drift. The lithology, the foraminiferal fauna, the molluscan fauna and the pollen flora all record cold, partly near-ice environment during their deposition. Elements of a boreal type foraminiferal fauna suggest that certain phases of the Sandnes Interstadial could have been slightly warmer. The shore level was very high. (b) Jaeren Stadial (40,000† 1000 years B.P.). Tills and glaciomarine deposits at several locailites are correlated with a Jaeren Stadial. (c) Nygaard Interstadial (41,000–50,000? years B.P.). Marine deposits representing a low shore-level phase, record cool to cold conditions. - (3)Early Weichselian. (a) Karmoy Stadial (older than 47,000 years B.P.). Gravelly and very bouldery tills at low stratigraphical levels in several prifles are correlated with a Karmoy Staidial.(b) Older deposits. Marine deposits which lie below the Karmoy Stadial till and on top of Eemian deposits at Bo II on Karmoy are being studies.

Norwegian Quaternary research has experienced rapid development during recent decades, from a rather weak position before 1960 to a more ‘normal’ position in 1986. A brief comparison with the status in 1960 is attempted, in order to understand this development and the present day status.

The chronology of the Late Pleistocene glacial history of North Westland, South Island of New Zealand, is refined by luminescence dating of sediments. It is demonstrated by two case studies that ages determined by different luminescence techniques agree well with the results of radiocarbon dating. Luminescence ages determined for sediments from two key sites of the Loopline Formation confirm the previous correlation of this unit with marine isotope stage (MIS) 4. This indicates that Late Pleistocene glaciers reached their last maximum extent in North Westland during the early part of the Otira (Last) Glaciation. Furthermore, initial dating evidence on coarse alluvial deposits in the lowlands indicates their formation during MIS 5b and MIS 5d. It is probable that these coarse gravel deposits are outwash related to glacial advances. If so, both advances were probably much less extensive than the glaciations during MIS 4 and MIS 2.

A short overview of NMR spectroscopic applications for the study of metal ion complexes of DNA oligomers is presented. One typical example is given to illustrate the scope of the methods: the NMR structure of a trans -DDP interstrand cross-linked duplex, d(CTCCTG*TGTCTC)·d(GAGATA*AGGAG). The solution structure of this double-stranded DNA oligonucleotide, containing a trans -diammineplatinum(II) interstrand cross-link, was determined using two-dimensional nuclear magnetic resonance (2D NMR) and NOE-restrained molecular dynamics and energy minimization refinement. The duplex is a non-palindromic 12/11-mer with a missing central residue in the lower strand and in addition it contains a GT mismatched base pair. The analysis indicated that an interstrand cross-link is established between G6-N7 of the upper strand and A18-N1 of the lower strand.

The single-stranded oligonucleotide 5′-d(CCTCGCTCTC) (I) was reacted with the antitumor trans platinum iminoderivative trans-[PtCl2{E-HN = C(OMe)Me}2] (trans-EE) and subsequently annealed with its complementary strand 5′-d(GAGAGCGAGG) (II). The platinated duplex was characterized by 1D and 2D proton NMR spectroscopy at 600 MHz. In agreement with previous studies by different techniques trans-EE was found to form a monofunctional adduct with the duplex involving the guanine residue. The modification by trans-EE has been found to induce only minor local distortion in the duplex geometry. Two key crosspeaks observed in the NOESY map corresponding to a close contact between G5-H8 and the methoxy and the methyl group, respectively, enabled us to dock the trans-EE complex with the duplex by geometry optimization. The results support the idea that the antitumor activity of trans-EE is related to lesion of DNA fundamentally different from that of cisplatin. Unexpectedly, the NOESY spectra indicated that at the high NaCl concentration used (0.2 M) the duplex was found to undergo slow deplatination. This was subsequently proved by HPLC. In a separate experiment on platination of the single strand in a salt free environment the HPLC analysis showed that the monofunctional adduct was not deplatinated, however, after 24 hours, additidnal minor isomers were detected.

A proton NMR study was performed on the copper(ll)-ciprofloxacin system. The proton relaxation times (T1) were determined from the titration data in acidic and basic media. In acidic medium the H5 signal is dramatically affected and it is assumed that copper is bonded to the quinolone through carbonyl and one of the carboxyl oxygens. Such bonding is in agreement with the X-ray literature data for the complex [Cu(cf)2]Cl2.6H2O isolated from the slightly acidic solution. There are additional significant changes in T1 of H3′ and H5′ atoms which suggest that the terminal nitrogen atom of the piperazine ring system-N4′ also interacts with copper in the basic conditions. Thus it is plausible that more than one species are present in the solution at high pH values.

Six successive zones with distinctive marginal moraines are recognized. Based on radiocarbon dates the ages of the three oldest zones are believed to be: older than 11,100 years B.P. (Vasdal event), about 10,900 B.P. (Glomfjord-Straumoy events), and between 10,400 and 9500 B.P. (Skjerstad event). The three youngest zones are Preboreal. Corresponding marine sediments, shorelines, glaciation limits and other glacial features are described.

The metal binding properties of three different oligodeoxyribonucleotides, one decamer and two dodecamers, have been studied by 1D and 2D 1H NMR spectroscopy. The sequential composition of the oligomers was chosen so as to provide a multitude of different binding site contexts: 5′-GACGGCCGTC (I), 5′-CGCGAATTCGCG (II), and 5′-ATGGGTACCCAT (III). Salts of three different metal ions: Mn(II), Co(II) and Ni(II), were used in titration experiments. The binding studies were carried out under duplex conditions. The influence of paramagnetic metal ions on protons adjacent to the binding site were followed by measuring line broadening and T1 relaxation times. We have previously proposed a rule for sequence-selective metal binding to G-N7 in oligodeoxyribonucleotides where the metal prefer the 5′-guanine residue in the order: 5′-GG ≥ GA > GT ≫ GC. This binding pattern is also observed in the present study for Mn(II) and Co(II). However, in sequence I Ni(II) does not follow the established selectivity rule showing greater affinity for 5′-G in the context 5′-GC than in the context 5′-GA. For II and III Ni(II) ions are seen to follow the selectivity rule. Fluctuation in the nucleophilicity of G-N7 along the duplex is probably a consequence of sequence-dependent variation in π-stacking interaction between base residues.

Palaeoecological studies carried out in the Chilean Lake District and Chilotan Archipelago (41°–43°S) record full-glacial and late-glacial pollen assemblages beginning just after 21000 and beetle assemblages after 18000, both sets extending until 10000 14C yr BP. Pollen records indicate that Subantarctic Parkland, the vegetation of the early millennia of record, changed after about 14000 yr BP to become open woodland and later North Patagonian Evergreen Forest. Assemblages of plants and beetles, responding more or less in unison to a strong rise in temperature (≥ 6°C), behaved in accord at around 14000 until 13000–12500 yr BP, the beetle fauna displaying a marked increase in obligate forest types. During full-glacial conditions (17400–16100 and 15300 and 14400 yr BP) and in the late-glacial interval (after about 13000 yr BP), however, climate evidently coerced populations dissimilarly, the pollen sequence showing an increase in plant taxa indicative of colder climate, whereas the beetle fauna underwent little or no variation. Contrasting climate modes implied by plants and beetles may be attributed to differential responses to apparent low-order temperature changes (≤ 2–3°C).

Isotopic records from polar ice cores imply globally asynchronous warming at the end of the last glaciation. However, 10 Be exposure dates show that large-scale retreat of mid-latitude Last Glacial Maximum glaciers commenced at about the same time in both hemispheres. The timing of retreat is consistent with the onset of temperature and atmospheric CO 2 increases in Antarctic ice cores. We suggest that a global trend of rising summer temperatures at the end of the Last Glacial Maximum was obscured in North Atlantic regions by hypercold winters associated with unusually extensive winter sea ice.

A radiocarbon chronology shows that piedmont glacier lobes in the Chilean Andes achieved maxima during the last glaciation at 13,900 to 14,890, 21,000, 23,060, 26,940, 29,600, and/=33,500 carbon-14 years before present ((14)C yr B.P.) in a cold and wet Subantarctic Parkland environment. The last glaciation ended with massive collapse of ice lobes close to 14,000(14)C yr B.P., accompanied by an influx of North Patagonian Rain Forest species. In the Southern Alps of New Zealand, additional glacial maxima are registered at 17,720(14)C yr B.P., and at the beginning of the Younger Dryas at 11,050 (14)C yr B. P. These glacial maxima in mid-latitude mountains rimming the South Pacific were coeval with ice-rafting pulses in the North Atlantic Ocean. Furthermore, the last termination began suddenly and simultaneously in both polar hemispheres before the resumption of the modern mode of deep-water production in the Nordic Seas. Such interhemispheric coupling implies a global atmospheric signal rather than regional climatic changes caused by North Atlantic thermohaline switches or Laurentide ice surges.

The climate and glacier fluctuations during the last interglacial-glacial cycle in Fennoscandia seem to correspond roughly in time with the climate fluctuations recorded in France-Germany-Holland. However, the climate in Fennoscandia was considerably colder, and the coldest phases are recorded as periods with glacier fluctuations. Admittedly, the exact age and amplitudes of some fluctuations are still much debated.

As many as 44 shell samples from deposits within end moraines and from glaciomarine deposits related to end moraines were used to radiocarbon date 5 morainal zones in Nordland. Zone A, Vega-Skarpnes Event, 12,300?200 years B.P. Zone B, Tj0tta-Troms0-Lyngen Event, 10,700?300 years B.P. Zone C, Nordli-Skjerstad Event, 10,100+200 years B.P. Zone D, Misvaer-Finneid Event, 9550?200 years B.P. Zone E, Rombak-0lfjell Event, 9300+200 years B.P. Introduction Altogether 46 shell samples collected by the writers from deposits related to marginal moraines in Nordland and southernmost Troms have been radiocarbon dated at Trondheim Radiological Dating Laboratory. The dates of as many as 39 of the samples correspond approximately with the expected ages. Seven samples must have been contaminated since their radiocarbon ages are obviously much too high or too low. On the basis of the 39 "correct" dates and 5 dates of samples collected by other scientists the excact radiocarbon ages of the moraines were determined. They were grouped into 5 major marginal moraine zones, A to E, which will be described in the following (cf. Figs. 1 and 3). The dated moraines were deposited in the sea and raised above sea level in post glacial time. Located above sea level the interior structure of the moraines and the corresponding sediments adjacent to the moraines can more easily be studied. Fig. 2 shows a generalized cross-section of a marinely deposited terminal moraine. The presented stratigraphical units vary in thickness in the different moraines, but the lithology of each unit is much the same in all moraines. Units Y1-Y3 are younger than the moraine, Mi-M6 correspond with the moraine and units 0,-02 are 1 Department of Geology, University of Bergen 2 Oljedirektoratet, Stavanger 3 Radiological Dating Laboratory, Trondheim older than the moraine. In situ marine shells in the beds correspond in age with the host sediment and can be used to date the different depositional phases. Transported shells, in general fragments, are usually older than the host sediment, and their radiocarbon dates represent maximum ages of the beds. Of particular interest are the M units which represent the end moraine and corresponding deposits. Most of the dated shells were found within the M units, and many within the glaciomarine beds M6 on the distal side of the moraine. The M6 unit is very thick at the moraine, and the thickness decreases quickly in distal direction. The lithology varies from gravelly clay with dropstones to bouldery gravel. Gravelly clay is most usual and the gravel/boulder content is highest near the moraines. Units Ml, M2 and M5 frequently contain transported shell fragments which are older than the moraine. High-arctic molluscan faunas which thrived in the cold, muddy and often brackish water near the ice fronts are usually found in unit M6. Due to the rapid sedimentation of clay near the ice fronts the shells lie scattered in the clay, and it is usually very time-consuming to collect enough shells for radiocarbon dating. Different faunas seem to be related to the different glacier events. A very distinctive Main-Arctic shore line was formed during the B-event. Shore lines which correspond with the younger events lie below the Main-Arctic shore line, and higher lying shore lines correspond with older events. The oldest moraines Several moraines on the Lofoten Islands (M0ller & Sollid 1972) are older than the A-event. They are not precisely dated. However, radiocarbon dates at about 18,000 years B.P. of lacustrine sediments at And0y Island (K. D. Vorren, 1978) together with radiocarbon dated marine beds on the shelf near And0y (T. Vorren, 1981) suggest that the age of the oldest moraines could be 18,000 to 20,000 years B.P. Geografiska Annaler ? 63 A (1981 ) 3-4 155 This content downloaded from 157.55.39.111 on Wed, 03 Aug 2016 05:40:11 UTC All use subject to http://about.jstor.org/terms BJ0RN G. ANDERSEN, FREDE B0EN, REIDAR NYDAL, ARNE RASMUSSEN AND PAL VALLEVIK

Former longitudinal profiles of Beardmore Glacier, an outlet through the Transantarctic Mountains, constrain polar plateau elevations near the center of Antarctica and ice-shelf grouding in the southern Ross Embayment. Three gravel drift sheets of late Quaternary age occur alongside Beardmore Glacier. Plunket drift, the youngest, is parallel to and 7–30 m above the present ice surface. The upper limit of Beardmore drift, intermediate in age, is within 35–40 m of the present ice surface near the polar plateau but about 1100 m above the present ice surface near the glacier mouth. The upper limit of Meyer drift, the oldest, is parallel to and 30–50 m above Beardmore drift. From correlation with numerically dated drifts farther north, we assign an early Holocene age to Plunket drift, a late Wisconsin age to Beardmore drift, and an age of marine isotope Stage 6 to Meyer drift. By our age model, Beardmore Glacier was close to current elevations in its upper reaches and thickened considerably in its middle and lower reaches during the last two global glaciations represented by Beardmore and Meyer drifts. Most likely, grounded ice in the southern Ross Embayment caused such thickening of Beardmore Glacier almost to the polar plateau. A concomitant decline in precipitation is implied by ice-cap retreat on the nearby Dominion Range and is consistent with little change of upper Beardmore Glacier. Ice-shelf grounding most likely resulted from lowered sea level and/or basal melting. Lower than present precipitation was probably caused by colder air temperatures and more-distant open water. The Plunket profile records Holocene ice-surface lowering from increased surface ablation, decreased ice flow, or grounding-line recession.

Former longitudinal profiles of Hatherton Glacier, an outlet through the Transantarctic Mountains, constrain nearby polar plateau elevations and ice-shelf grounding in the southwestern Ross Embayment. Four gravel drift sheets of late Quaternary age beside Hatherton Glacier are, from youngest to oldest, Hatherton, Britannia I, Britannia II, and Danum. The Hatherton drift limit is uniformly 20 to 70 m above the present ice surface. The Britannia II drift limit is within 100 m of the present surface of uppermost Hatherton Glacier but is 450 m above middle Hatherton Glacier. Extrapolation of this profile downglacier indicates a surface elevation 1100 m above the present Ross Ice Shelf. The Britannia I drift limit is parallel to, but 50–100 m below, Britannia II drift. The Danum drift limit is parallel to, but 50–100 m above, the Britannia II profile. From correlation with drifts near McMurdo Sound and from local 14C dates, we assign an early Holocene age to Hatherton drift, a late Wisconsin age to Britannia drifts, and an age of marine isotope Stage 6 to Danum drift. By our age model, the upper reaches of Hatherton Glacier (and presumably the adjacent polar plateau) have not exceeded their current elevations by more than 100–150 m during the last two complete global glacial-interglacial cycles, whereas the middle and lower reaches of Hatherton Glacier have thickened considerably during the last two global glaciations (late Wisconsin and marine isotope Stage 6). The effect of ice-shelf grounding probably was the major control of these changes of Hatherton Glacier. Holocene ice-surface lowering probably represents the last pulse of grounding-line recession in the southwestern Ross Embayment.

Pa de praktisk talt snauskrapte 800—1000 m hoye heiene sonnenfor indre del av Josenfjorden ligger en imponerende, flere km lang, opptil 5—7 m hoy, skarp, morenerygg. Den bestar nesten utelukkende av hodestore til husstore, kantrundete grunnfjellsblokker (gneis og granitt). Bondene i disse traktene kaller den Trollgaren (fig. 27). Det var kjennskapet til Trollgaren som ledet meg inn pa. undersokelsene i Ryfylke. Jeg har funnet lignende morenerygger pa fjellene sydover mot Lysefjorden. De er sannsynligvis alle avsatt ved samme brerand, og horer til det jeg har kalt Trollgaren-stadiet. Vestenfor Trollgaren-stadiet ligger det morener etter et eldre, mektigere bre-stadium, Lysefjord-stadiet. Disse moreneryggene loper som kjempemessige steingarder, tvers over snauf jellet mellom fjordene (dalene) og videre som sidemorener langs fjord (dal-) sidene til de nar de store, tidligere kjente frontmorener f. eks. i Lysefjordmunningen, foran Haukelivann (Esmarkmorenen) og foran O. Tysdalsvann. Slik har jeg klart a folge...

A multidisciplinary study of crustal movements in coastal Maine has shown that parts of the state9s coastal zone are subsiding. This subsidence is associated with seismic activity that has persisted locally since at least the 1800s. Bedrock structural studies have not produced evidence of major Holocene faulting, but measured horizontal rock strains may be related to Mesozoic graben development in the adjacent Gulf of Maine. The crustal down warping is most apparent in eastern Maine, where releveling data indicate a modern subsidence rate of as much as 9 mm/yr. The anomalously rapid sea-level rise resulting from this subsidence has caused erosion and submergence of archeological sites and historical man-made structures. However, the altitudes of glaciomarine deltas and the distribution of dated archeological sites show that the present subsidence rates have not persisted throughout Holocene time.