GSA Bulletin: Holocene Relative Sea-Level History of Franz Josef

Holocene relative sea-level history of Franz Josef Land, Russia

Steven L. Forman* Department of Geological Sciences, University of Illinois, Chicago, Illinois 60607-7059

Richard Weihe Byrd Polar Research Center and Department of Geological Sciences, Ohio State University, Columbus, Ohio 43210-1002

David Lubinski Institute of Arctic and Alpine Research and Department of Geological Sciences, University of Colorado, Boulder, Colorado 80309-0450

Gennady Tarasov Sergey Korsun Murmansk Marine Biological Institute, 17 Vladimirskaya Street, Murmansk, Russia 183023 Gennady Matishov }

ABSTRACT INTRODUCTION

One of the largest uncertainties in ice-volume changes during the The pattern of postglacial emergence for many areas in the Northern late Quaternary Period is the extent of ice sheets over the Barents and Hemisphere is pivotal in assessing the distribution of past ice-sheet loads Kara seas. Field research on central and eastern Franz Josef Land, and deglacial history. Observations on postglacial emergence are also Russia, provide new observations on postglacial emergence and important for developing a better understanding of the glacio-isostatic deglaciation that further constrain the magnitude and timing of late adjustment process and the constraining properties of the underlying solid Weichselian glaciations. Radiocarbon dating of driftage from raised- Earth (Cathles, 1975; Peltier, 1974). Recent refinements in models of marine sequences place deglacial unloading prior to 9.4 ka. At a num- mantle viscoelastic structure and an improved understanding of the extent ber of localities within 1 to 2 km of the present glacier margin, in situ and chronology of the Laurentide and Fennoscandinavian ice sheets pro- shells from raised-marine sediments yield 14C ages between 9.7 and vide a basis for estimating variations in ice-sheet thickness during the last 8.4 yr B.P., evidence that outlet glaciers were at or behind present deglaciation (Peltier, 1994; Lambeck, 1995). These earth rheological margins by the early Holocene Period. models accommodate site-specific relative sea-level and global eustatic The altitude of the marine limit on Franz Josef Land ranges records (Fairbanks, 1989), providing new insight into the balance between from 49 to 20 m above sea level (asl) and is low compared to eastern glacier cover and changes in global sea-level in the past approximately Svalbard (110 to 60 m asl). The age of the marine limit ranges from 20 000 yr (Tushingham and Peltier, 1991; Peltier, 1994). ³10.4 ka to ca. 6.0 ka and exhibits greater diachrony where emer- One of the largest uncertainties in ice volume changes in the late Qua- gence is <35 m. A low initial rate of emergence reflects glacio-isosta- ternary Period is the timing and geometry of glaciers over the shelf seas tic compensation offset by a eustatic rise in sea level, and perhaps an bordering the Arctic Ocean. Reconstructions of late Weichselian ice-sheet additional component from renewed water loading of the Barents Sea extent in the Barents Sea region range from a contiguous marine-based ice after deglaciation. The presence of raised beaches at 1 to 4 m asl that sheet over much of the European arctic (e.g., Peltier, 1994; Lambeck, are 1 to 2 ka indicates that uplift is incomplete. An exponential 1995), to smaller, coalescent ice caps based on arctic archipelagos (e.g., extrapolation of uplift data for Franz Josef Land and eastern Sval- Siegert and Dowdeswell, 1995; Lambeck, 1995). This disparity in ice bard yields current maximum uplift estimates of 0.7 to 1.6 mm/yr, an sheet reconstructions reflects the paucity of field observations that con- inferred <5.5 m of uplift remaining. These values are at least 50% to strain the extent, thickness, and timing of late Quaternary glacial events in 80% lower than the inferred uplift residual for a modeled ice sheet in northern Eurasia. the Barents and Kara seas. The discrepancy indicates that further re- Critical field observations needed to constrain the magnitude and dis- finement is needed for this ice-sheet model. tribution of past glacier loads and the timing of deglaciation are the height The compilation of emergence data from Franz Josef Land, and age of raised-beach deposits. Raised beaches were initially recog- Svalbard, and Novaya Zemlya confine maximum glacio-isostatic nized on Franz Josef Land, Russia, during early geologic exploration compensation to the Barents Sea; comparatively minor ice sheet (Koettlitz, 1898). The first systematic studies of postglacial emergence on loads were over Novaya Zemlya and the southeastern Barents Sea. Franz Josef Land were undertaken by Dibner (1965) and Grosswald Emergence isobases since 5 and 9 ka descend northward across Franz (1973). They identified extensive raised-beach sequences on Hooker, Josef Land, indicating a diminishing glacio-isostatic response into the Hayes, Alexandra, and other islands in the Franz Josef Land archipelago. Arctic Ocean. Most notably, they collected five driftwood samples from raised beaches for 14C dating, providing the first age constraints (ca. 6000 yr B.P.) on deglaciation and emergence of Franz Josef Land. Only in the past five *e-mail: [email protected] years, with improved access to the Russian arctic, are new assessments

GSA Bulletin; September 1997; v. 109; no. 9; p. 1116–1133; 17 figures; 3 tables

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emerging on the magnitude and timing of Quaternary glaciations in northern Eurasia (Glazovskiy et al., 1992; Näslund et al., 1994; Polyak and Solheim, 1994; Polyak et al., 1995; Forman et al., 1995, 1996; Lubinski et al., 1996). This contribution presents seven new postglacial emergence records and stratigraphic assessments on deglaciation for central and southern Franz Josef Land (Fig. 1); in combination with other recent re- sults (Glazovskiy et al., 1992; Näslund et al., 1994; Forman et al., 1995, 1996), these form a basis for an enhanced representation of the pattern of Holocene emergence in the northern Barents Sea.

NEAR-SHORE CONDITIONS AND THE RAISED BEACH RECORD

Our field research, in August 1992 and 1993, provides insight on the pattern of postglacial emergence and deglaciation for Hayes, Hall, Wilczek, Klagenfurt, Brady, Leigh Smith, Koldewey, Champ, and Wiener Neustadt islands, Franz Josef Land, Russia (Figs. 1 and 2). These studies concentrated on determining the elevational extent of raised-beach landforms and providing a chronologic and stratigraphic assessment of raised- marine sequences. Radiocarbon dating of drift from raised-beach landforms and mollusks from stratigraphic sections provide chronologic control to relate geomorphic and stratigraphic records. Geomorphic assessment is derived from field observations using 1:200 000, 1:100 000, and 1:50 000 scale maps; aerial photographs were not available for our field studies. The studied islands, in the central and the southern part of the archipelago, are bounded by sounds and fjords that have water depths of >250 m (Matishov et al., 1995). Most of the archipelago (85%) is covered by glaciers, but all islands studied have low elevation (<100 m asl) forelands partially covered by raised-marine sediments. Most sounds and fjords in the archipelago are usually covered by sea ice for 9 to 10 months of the year (Denisov et al., 1993). Sea-ice conditions in the interisland channels during July and August are variable, ranging from open-water conditions to full sea-ice coverage. Gravel and boulder beaches dominate the present shore of central and eastern Franz Josef Land. Storm-beach gravels and sea-ice–pushed ridges often extend 2 to 3 m above the present high-tide level. The tidal range on Franz Josef Land is approximately 0.5 m (Denisov et al., 1993). All mea- Figure 1. Franz Josef Land in the west Eurasian arctic and loca- surements of altitude for raised beaches are determined in reference to the tion of studied islands within the archipelago. high-tide swash mark (m asl) by a Leitz digital altimeter with an analyti- cal precision of ±0.1 m. The altitude of a landform was measured multiple times by two different altimeters and these determinations usually agree RADIOCARBON DATING within ±1 m. The maximum estimated error in measuring altitude, in- cluding variable relief of a raised-marine landform, is ±2 m. Age constraint on marine inundation and deglaciation is provided by 14C The present altitude of raised beaches on Franz Josef Land reflects dating of driftwood, whalebone, walrus bone, and shell from raised-marine principally two competing processes; the postglacial rise in global sea sediments. Driftwood was preferentially collected from the raised-beach level and isostatic up-warping of the lithosphere with disintegration of the sequences because of its suitability for 14C dating. The outer rings of drift- last ice sheet that occupied the Barents Sea. Global sea level has been rel- wood logs were sampled to obtain 14C ages in close association with the atively stable in the past 6000 yr (Kidson, 1982); thus, raised beach sea-level depositional event (Table 1). If driftwood was not located, whale- elevation attained since the mid-Holocene Period reflects predominantly bone and walrus-skull bone were retrieved for 14C dating. Bones were sec- isostatic compensation. However, in areas where postglacial emergence tioned by saw and an internal, well-preserved dense part of the bone was was modest (<50 m), relatively brief (hundreds to thousands of years) ar- submitted for 14C dating. The collagen-dominated gelatin extract from each rests in sea level or transgressive-regressive events (<2 m) have been doc- bone was dated, which in previous studies has yielded accurate 14C ages umented, reflecting the interplay between eustasy, isostasy, and steric and (e.g., Forman, 1990; Forman et al., 1995). The apatite fraction for two sam- nonsteric changes in sea level (e.g., Hafsten, 1983; Svendsen and ples, a whalebone (GX-18313A) and a walrus-skull bone (GX-18306A), Mangerud, 1987; Forman, 1990, 1996 Fletcher et al., 1993). Changes in was analyzed in addition to the gelatin extract (Table 1). The apatite 14C age the course of relative sea level on an emerging coastline are identified as for the whalebone overlaps at one sigma with the corresponding 14C age on constructional (broad raised terrace) or as an erosional (escarpment) land- the gelatin extract. However, the 14C age on the apatite fraction from the form in the raised-beach sequence, reflecting the interaction between sea walrus bone was younger than the corresponding 14C age on the collagen- level, sediment supply, and wave energy. dominated fraction. Potential contamination of this walrus bone is probably

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limited to the apatite fraction, because the 14C age on the gelatin extract RELATIVE SEA-LEVEL RECORD overlaps at one sigma with the 14C age on driftwood from a similar elevation. Most 14C ages on shells are on a single valve by accelerator mass spec- Brady and Leigh Smith Islands trometry (AMS) analysis. Prior to dating, all shells received a 50% leach in HCl to remove potential contaminants. To compensate for the marine 14C On a broad strandflat on southwestern Brady Island (Figs. 2 and 3), the reservoir effect, 440 yr were subtracted from all 14C ages on whalebone and elevational limit of marine influence at 34 ± 2 m asl is identified as a shell. This reservoir correction is derived from pre-World War II bomb shells washing limit or erosional notch into drift-covered bedrock. A few hun- (A.D. 1945) from Nordic seas (Mangerud and Gulliksen, 1975; Olsson, dreds of meters seaward of the washing limit is a broad (100–300 m wide) 1980). Shells collected in the late nineteenth century from Franz Josef Land constructional beach terrace that crests at 32 to 34 m asl. Below the and Novaya Zemlya yielded similar 14C values (Forman and Polyak, 1997). marine limit at 21 to 23 m asl is a 1–3-m-high escarpment, accentuated by

Figure 2. Generalized topography of Leigh-Smith and Brady islands. Hachured areas indicate study sites. At least 90% of the area of these islands is covered by glacier ice or permanent snow banks.

Figure 3. The marine limit and lower regressional raised beaches on southwestern Brady Island, Franz Josef Land. R. Weihe (1.8 m tall) is standing on drift surface (diamicton) at 35 m above sea level (asl), immediately above marine limit. Ma- rine limit at 34 ± 2 m asl is clearly shown as the elevational limit of wave-washed gravels. Base of snow bank in the back- ground at 22 ± 2 m asl demarks an escarpment associated with arrest 2.

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a permanent snow bank, eroded into beach gravels and bedrock (Fig. 3). Discrete strandlines occur below the escarpment to the modern storm- beach limit at 2 to 3 m asl. Despite a concentrated search, no drift was found associated with the washing limit or constructional beach ridge that demarks the marine limit. However, one piece of driftwood was located at 29 m asl on a regressional strand below the marine limit, but above the escarpment. This driftwood yielded the 14C age of 8135 ± 115 yr B.P. (GX-19493) providing a minimum estimate on construction of the broad beach ridge associated with the marine limit. Driftwood from 21 m asl and near the escarpment base gave the age of 5980 ± 100 yr B.P. (GX- 19492), providing a close limiting age on escarpment formation (Fig. 4a). The marine limit on the small and rocky southern foreland of Leigh Smith Island was measured at 40 ± 2 m asl and identified by a washing limit into drift-covered bedrock. Apparently undisturbed marine-limit gravels were traced to within a few hundred meters of the present margin of the ice cap that covers Leigh Smith Island. Steep wave-washed bedrock occurs between approximately 35 m asl and 20 m asl, confounding the retrieval of drift that can be confidently fixed to a past sea level. Driftwood clearly associated with raised beach surfaces were only located from 25 m asl to just above the storm beach limit at 5 m asl (Fig. 4b).

Hayes, Fersman, and Newcombe Islands

The relative sea-level records for Hayes, Fersman, and Newcombe islands have been combined because of the close proximity of these islands and identical elevation of the marine limits (Fig. 5a). Numerous basaltic dikes, on which littoral gravels have been banked to a height of 21 ± 2 m asl, are prominent on northeast Hayes Island. The marine limit on Fersman Island (Fig. 5a), a small island 1 km northwest of the study area on Hayes Island, is identified as a wave-washed escarpment into glacial drift at 21 ± 2 m. On Newcombe Island a similar washing limit is found at 21 ± 2 m asl, eroded into drift covered bedrock. No driftage was found on the marine limit surface on these islands. The highest drift materials found are a 0.5-m-long log from Hayes Island and a 2-m-long whale rib from Newcombe Island, both at 17 ± 1 m, which yielded the respective 14C ages of 5435 ± 80 yr B.P. (GX-18308) and 4935 ± 80 yr B.P. (GX-18313G). These ages place emergence in this area before ca. 5400 yr (Fig. 6). One of the largest unglaciated forelands in the archipelago is on Hayes Island, rising to approximately 100 m asl, at the fore of the present ice cap (Fig. 5a). The Romantikov River and its tributaries that drain the ice cap, have incised into the foreland, exposing a sequence of marine sediments deposited with deglaciation and postglacial emergence (Fig. 7). The basal Figure 4. (a) Height-age relation for raised beaches on Brady Island sediment, currently approximately 5 m asl is a silty-sandy mud that con- and (b) Leigh-Smith Island. Arrests in emergence are inferred from the tains dropstones and abundant paired valves of Hiatialla arctica, Mya occurrence of escarpments and >1 ka range in 14C ages for drift found truncata, and Astarte borealis. One valve of M. truncata from the marine 14 on <3 m elevational span of raised beach. The size of the plotting symbol mud yielded the AMS C age of 5090 ± 65 yr B.P. (AA-10247). This approximates errors in determining altitude of approximately 1 m and mud is overlain by a stratified medium-to-fine sand, containing abundant 14C age determination errors of approximately 100 yr. shells, and is in turn capped by raised-beach gravels that form a terrace at 10 m asl. The sedimentologic sequence indicates shallowing marine conditions with postglacial emergence that commenced prior to ca. 5100 yr. The lowest identified raised beach on Hayes Island at 1 m asl is located Champ and Wiener Neustadt Islands in a northward-facing, protected embayment, shielded from storm waves that construct 2–3-m-high storm beaches on more exposed coastlines. A Two steeply sloping small (<3 km2) forelands were studied on the partially buried log from this raised surface yielded the age of 1075 ± 60 southern coasts of Champ and Wiener Neustadt islands (Fig. 5a). These yr B.P. (GX-18307). Driftwood from a raised beach at 2 m asl, on a pro- islands are covered almost completely by ice caps or permanent snow- tected part of the northern coast of Newcombe Island, yielded the 14C age fields, many which terminate at the coast. The highest discernable raised of 1830 ± 65 yr B.P. (GX-18316). Ages of 1 to 2 ka for the lowest raised marine landform on Champ Island is a beach berm constructed against a beaches at 1 to 2 m asl indicate that emergence is incomplete (Fig. 6). scree slope at 19 ± 2 m asl. Regressional strandlines were identified down

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to the present shoreline. Exposed in a channel bank of a meltwater stream <30 m (Matishov et al., 1995). The marine limit on Klagenfurt Island is is a well-sorted, stratified, medium to coarse sand, containing slightly clearly delimited at 20 ± 1 m asl by a broad (100–300 m wide) constructional abraded valves of Hiatella arctica and Mya truncata (Fig. 8). These sedi- terrace built against bedrock or a drift-covered surface. A marine limit ele- ments were deposited in a littoral-sublittoral environment during emer- vation (19 ± 2 m asl) was registered on nearby Wilczek Land, indicating that gence. The sequence is within a few tens of meters of a present glacier there was little time between deglaciation of Klagenfurt and Wilczek Land margin and is apparently undisturbed. One valve of Hiatella arctica from islands. On Klagenfurt Island, immediately below the marine limit, there is the sublittoral sand yielded the AMS 14C age of 9386 ± 90 yr B.P. (GX- a noticeable discontinuity in the regressional sequence demarked by an 19207-AMS). The proximity of the sublittoral sediment to the present ice escarpment at 16 to 18 m asl cut into marine-limit gravels. Below this cap margin and the age of included shells indicate that this outlet glacier escarpment, regressional strandlines occur to the present storm beach, was at or behind its present margin by at least 9400 yr B.P. which crests at 2 to 3 m asl. Driftwood retrieved from near the base of the On a narrow (<0.5 km wide) foreland on southern Wiener Neustadt Island, escarpment at 17 m asl yielded a 14C age of 4925 ± 160 yr B.P. (GX-18296), wave-washed rounded gravels are traced up to 12 m asl (Fig. 9). Glaciogenic which provides a close limiting age on regression from the escarpment and and marine sediment are identified along approximately 1-m-high banks of a minimum limiting age on deglaciation (Fig. 10a). a stream that has incised into this narrow foreland. A stream bank exposure of a raised beach at 10 m asl contains a clast-rich diamicton underlain by Wilczek Island stratified sand and silt (Fig. 9). In another stream bank exposure, lower in the regressional sequence at 3 m asl, is a stratified, medium to coarse sand with One of the most southerly islands in the archipelago exposed to the slightly abraded valves of Hiatella arctica and Mya truncata, overlain by fetch of the Barents Sea is Wilczek Island (Fig. 5b). We studied a gently beach gravels (Fig. 9). One valve of Hiatella arctica from this littoral/sub- sloping foreland along the southwestern coast of the island. The marine littoral sediment yielded the AMS 14C age of 8970 ± 100 yr B.P. (GX- limit at 25 ± 1 m asl is clearly demarked by the elevational extent of wave- 21170-AMS), providing another constraint on deglacial invasion of the sea. washed gravels against drift or a scree slope. Below the marine limit at 22 to 20 m asl, a discontinuous escarpment (0.5 to 1 m high) has been eroded Klagenfurt Island into marine limit gravels. Strandlines occur from the escarpment to the modern storm beach at 3 to 4 m asl. There was a distinct absence of drift- Klagenfurt Island is small and approximately 2 km off the southern coast age above 20 m asl to the marine limit. However, below 20 m asl there is an of Wilczek Land Island (Fig. 5b). The water depth between these islands is abundance of whalebone and driftwood on the raised beaches. The high-

TABLE 1. RADIOCARBON AGES ON DRIFTWOOD, SHELL, WHALEBONE, AND WALRUS BONE FROM RAISED MARINE DEPOSITS, CENTRALAND SOUTHERN FRANZ JOSEF LAND, RUSSIA Dated material Shoreline Laboratory 14C Laboratory Laboratory altitude age or reservoir number reference (m asl) corrected age* (d13C) (yr B.P.) Brady Island: marine limit 34 ± 1 m asl Log (2 m long) on raised beach 5 2560 ± 85 Ð23.8 GX-19489 Log (1 m long) on raised beach 9 3955 ± 110 Ð24.6 GX-19488 Tree root-plate (2 m long) buried in raised beach 12 4150 ± 90 Ð26.9 GX-19490 Whale skull partially buried in raised beach 16 4855 ± 80* Ð16.9 GX-20740G¤ Tree root-plate (0.5 m long) buried in raised beach 19 5100 ± 95 Ð24.4 GX-19491 Log (1 m long) on raised beach 21 5980 ± 100 Ð24.5 GX-19492 Wood fragments (0.3 m long) within raised beach 29 8135 ± 115 Ð25.4 GX-19493 Leigh Smith Island: marine limit 40 ± 2 m asl Log (3 m long) on raised beach 5 1055 ± 65 Ð26.0 GX-20741 Tree root-plate (0.5 m long) buried in raised beach 10 2010 ± 75 Ð23.6 GX-20742 Log (1 m long) in raised beach 14 2790 ± 70 Ð24.0 GX-20743 Log (8 m long) on raised beach 19 4555 ± 80 Ð25.1 GX-20744 Log (3 m long) buried in raised beach 25 5080 ± 80 Ð23.4 GX-20745 Hayes (H), Fersman (F) and Newcombe (N) Islands: marine limit 21 ± 1 m asl Log (1.5 m long) buried in raised beach (H) 1 1075 ± 60 Ð25.1 GX-18307 Log (1.5 m long) on raised beach (N) 1.5 1830 ± 65 Ð25.8 GX-18316 Log (2 m long) on raised beach (N) 3 2040 ± 65 Ð27.6 GX-18312 Log (4+ m long) on raised beach (F) 6 2980 ± 125 Ð24.7 GX-18310 Tree root-plate (1 m long) buried in raised beach (F) 8 3635 ± 135 Ð26.3 GX-18309 Tree root-plate (1 m long) buried in raised beach (N) 9 3885 ± 140 Ð25.5 GX-18315 Log (3 m long) on raised beach (N) 12 4315 ± 75 Ð27.2 GX-18314 Whale rib (2 m long) imbedded into raised beach (N) 17 4935 ± 80* Ð17.2 GX-18313G¤ Whale rib (2 m long) imbedded into raised beach (N) 17 4775 ± 165* Ð15.3 GX-18313A# Log (0.5 m long) on raised beach (H) 17 5435 ± 80 Ð25.0 GX-18308 Paired M. truncata from marine muds (H) >5 5090 ± 65* 0 AA-10247 Driftwood (H) 10 4775 ± 115 Grosswald (1961) Champ (C) and Wiener Neustadt (W) Islands M. truncata valve from sublittoral sand (C) >9 9386 ± 90* +0.7 GX-19027-AMS H. arctica valve from sublittoral sand (W) >3 8970 ± 100* +0.9 GX-21170-AMS Klagenfurt Island: marine limit 20 ± 1 m asl Log (1 m long) on raised beach 4 1850 ± 65 Ð23.8 GX-18298 Log (1.5 m long) on raised beach 7 3195 ± 70 Ð25.2 GX-18297 Tree root-plate (1 m long) buried in raised beach 10 3635 ± 75 Ð24.6 GX-18294 Tree root-plate (0.5 m long) buried in raised beach 14 4870 ± 155 Ð25.4 GX-18295 Log (0.75 m long) on raised beach 16 4830 ± 115 Ð24.6 GX-21368 Log (1 m long) on raised beach 17 4925 ± 160 Ð26.4 GX-18296

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est drift materials identified are a 1.5-m-long log and a walrus skull found 19506), 6470 ± 100 yr (GX-19505) and 6055 ± 95 yr B.P. (GX-20747) on below the escarpment at 20 ± 1 m asl, which yielded the respective 14C driftwood from regressional strands 1 to 4 m below the marine limit indi- ages of 5830 ± 85 yr (GX-18304) and 5880 ± 85 yr B.P. (GX-18306G). cate a slower rate of initial emergence, compared to later in the Holocene These ages are minimum estimates on the attainment of the marine limit (Fig. 11a). Driftwood retrieved from 10 ± 1 m asl, approximately 8 m and deglaciation (Fig. 10b). below the escarpment, gave the 14C age of 3625 ± 90 yr B.P. (GX-19503), providing a minimum constraining age on escarpment abandonment. Two Koldewey Island pieces of driftwood from 16 and 14 m asl yielded anomalously young ages of 3230 ± 85 yr (GX-19504) and 1645 ± 70 yr B.P. (GX-20748), which Koldewey Island is small and (Fig. 5b) bounded by interisland sounds probably represent displaced drift from lower raised beaches, indicating that exceed water depths of 250 m (Matishov et al., 1995). The highest anthropogenic disturbance (Fig. 11a). evidence for marine inundation on Koldewey Island is registered at 24 ± 1 m asl, consistent with marine limit determinations on adjacent Klagen- Hall Island furt and Wilczek islands of 20 ± 1 and 25 ± 1 m asl. The marine limit on Koldewey Island is identified on a variety of landscape positions. The Field studies concentrated on the southeastern glacier-free forelands on washing limit on interfluves is identified by an erosional escarpment into Hall Island (Fig. 5b). The limit of marine influence was identified to 32 ± drift-covered bedrock. In contrast, the marine limit within valleys is a 2 m asl as a washing limit eroded into drift-covered bedrock. Associated broad (100–300 m wide) constructional beach; ice-pushed ridges cover with this washing limit is a discontinuous constructional beach with the surface (cf. Martini, 1981). Immediately below the marine limit at 18 superimposed ice-pushed ridges (cf. Martini, 1981) that crests at 32 m asl. ±1 m asl there is a prominent escarpment cut into beach gravels and These well-preserved marine limit features are within a few hundreds of bedrock that was visually traced for over 2 km and identified on both sides meters of the present margin of outlet glaciers of the Hall Island ice cap. of the island. Below the escarpment regressional strandlines occur to the A 14C age of 8655 ± 145 yr B.P. (GX-19495) on driftwood from a present storm beach at 2 to 3 m asl. regressional strandline, approximately 1 m below the marine limit, pro- A piece of driftwood deposited against the marine limit escarpment provides a minimum constraining age on deglacial emergence (Fig. 11b). vides a close, but minimum constraining age of 7890 ± 140 yr B.P. (GX- Driftwood located inside Severe Bay at 23 m asl gave the 14C age of 8310 19508) on marine inundation. Radiocarbon ages of 7335 ± 105 yr (GX- ± 145 yr B.P. (GX-19512), at least 1000 yr younger than the inferred age

TABLE 1. (Continued) Dated material Shoreline Laboratory 14C Laboratory Laboratory altitude age or reservoir number reference (m asl) corrected age* (d13C) (yr B.P.) Wilczek Island: marine limit 25 ± 1 m asl Log (0.75 m long) buried in raised beach 4 975 ± 105 Ð24.6 GX-18299 Log (2 m long) on raised beach 6 2040 ± 115 Ð26.3 GX-18300 Log (2.5 m long) on raised beach 10 3295 ± 130 Ð25.2 GX-18301 Log (0.75 m long) buried in raised beach 12 3660 ± 100 Ð26.1 GX-21367 Log (1 m long) on raised beach 15 5255 ± 80 Ð25.7 GX-18302 Fragment from whale skull 16 4425 ± 110* Ð17.0 GX-21366G¤ Log (1.5 m long) on raised beach 18 5205 ± 80 Ð24.6 GX-18303 Log (1.5 m long) on raised beach 20 5830 ± 85 Ð26.9 GX-18304 Walrus skull in raised beach 22 5880 ± 85* Ð16.5 GX-18306G¤ 5030 ± 170* Ð11.6 GX-18306A# Koldewey Island: marine limit 24 ± 1 m asl Log (2 m long) in raised beach behind storm beach 2 1100 ± 70 Ð25.0 GX-19507 Log (1.5 m long) on raised beach 3 1465 ± 105 Ð22.9 GX-19501 Log (0.75 m long) on raised beach 14 1645 ± 70 Ð26.0 GX-20748 Log (2 m long) on raised beach 6 2870 ± 105 Ð26.8 GX-19502 Log (1.5 m long) on raised beach 16 3230 ± 85 Ð27.1 GX-19504 Log (1 m long) in raised beach 10 3625 ± 90 Ð26.1 GX-19503 Log (2 m long) in raised beach 20 6055 ± 95 Ð25.9 GX-20747 Tree root-plate (0.5m long) buried in raised beach 21 6470 ± 100 Ð24.8 GX-19505 Log (0.5 m long) on raised beach 23 7335 ± 105 Ð25.3 GX-19506 Log (5 m long) in raised beach at marine limit 24 7980 ± 140 Ð25.8 GX-19508 Outer Hall Island: marine limit 32 ± 2 m asl Log (1 m long) in raised beach 4 1325 ± 105 Ð23.7 GX-19496 Log (1 m long) in raised beach 7 2265 ± 85 Ð24.6 GX-19497 Tree root-plate (0.75 m long) buried in raised beach 9 3515 ± 85 Ð23.4 GX-19498 Log (1 m long) on raised beach 11 3770 ± 90 Ð25.1 GX-19515 Wood fragments (0.3 m long) within raised beach 18 5010 ± 95 Ð25.7 GX-19500 Log (1.5 m long) buried in raised beach 23 6490 ± 130 Ð25.2 GX-19494 Log (1 m long) buried in raised beach 31 8655 ± 145 Ð24.4 GX-19495 Severe Bay, Hall Island: marine limit 23 ± 2 m asl Splinter log (2 m long) found on raised beach 23 8310 ± 145 Ð24.6 GX-19512 Whale skull from washed sublittoral sediments >8 9450 ± 165* Ð17.3 GX-19511G¤ Paired valves of M. truncata from delatic sands >3 9655 ± 100* +1.9 GX-19509 Paired valves of M. truncata from delatic sands >7 8260 ± 115* +0.9 GX-19510 *440 years has been subtracted from 14C ages of marine subfossils to compensate for the 14C oceanic reservoir effect (Mangerud and Gulliksen, 1975; Olsson, 1980). A d13C value of 0 was assumed for marine carbonate analyzed by the National Accelerator Mass Spectrometry facility at the University of Arizona. ¤The collagen-dominated gelatin extract for all whalebones was dated. #Radiocarbon age on the apatite extract.

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of the equivalent raised beach outside the bay. This log was found at the other marine fauna. The presence of abundant paired mollusks with base of a scree slope and may have been retransported downslope with periostracums and hinge ligaments, and common burrowing structures postglacial regression. indicates an in situ fauna. Most notable is an increase in bed dips from 5° A sequence of marine sand beneath raised-beach gravels along the to 10° at the section base to 25° to 30° up-section, concomitant with a inner part of Severe Bay indicates even earlier deglaciation (Fig. 12). general coarsening in the sand fraction. The plunge of the beds Exposed in river and coastal sections is a sequence of stratified sand and (155°–120°) indicates a sediment source from the northwest, toward the silty sand, containing isolated dropstones. Centimeter-scale beds coarsen present outlet glacier margin. The sequence was truncated with regression upward from a medium-to-coarse sand to a sandy silt. Throughout the and emplacement of beach gravels on top of the section. Radiocarbon ages sequence are paired mollusks of Macoma calcarea, Mya truncata, and on paired Mya truncata shells from this sequence place deposition of these

Figure 5. (a) Location of study sites on Hayes, Fersman, Newcombe, Wiener Neustadt, and Champ Islands, and (b) on Hall, Koldewey, Wilczek, Kla- genfurt, and Wilczek Land Is- lands. Hachured areas indicate study sites.

1122 Geological Society of America Bulletin, September 1997

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Figure 6. Height-age relation (asl—above sea level) for raised beaches on Hayes, Fersman, and Newcombe Islands. Ages on deglaciation from Wiener Neustadt and Champ Islands provide an older estimate on deglacial invasion of the sea. The size of the plotting symbol approximates errors in determining altitude of approximately 1 m and 14C age determination errors of approximately100 yr.

near-shore sands between ca. 9700 and 8300 yr (Table 1; Fig. 12). This sedimentary sequence represents deltaic sedimentation beyond a glacier margin. The lowest, shallowly inclined beds (dips of 5° to 10°) mark bot- tomset deposition. The overlying more steeply inclined beds may reflect progradation of the delta front with fall or stabilization of relative sea level, or a slight advance of a nearby (within 0.5 km) outlet glacier.

MARINE LIMIT AND DEGLACIATION

Available chronologic control places retreat of the northern and western margins of the Barents Sea ice sheet by ca. 13 000 yr ago (Forman et al., 1987; Svendsen et al., 1992; Polyak and Solheim, 1994; Elverhøi et al., 1995; Lubinski et al., 1996). Geomorphic and stratigraphic evidence places deglacial unloading of central Franz Josef Land prior to 9.4 ka. A previous study of emergence along British Channel on western Franz Josef Land indicates deglacial unloading prior to 10.4 ka. The apparent age difference between deglaciation in the adjacent Barents Sea ca. 13 ka and adjacent Franz Josef Land ca. 10.4 ka reflects either relict glacier cover, or a hiatus in datable material delivered to the archipelago. There is a distinct absence of boulder-dominated beaches at the marine limit, although boulder beaches are common lower in the regressional sequence and at the present shoreline. The highest level of marine incursion is commonly demarcated by a discrete washing limit eroded into glacial drift or in proximity to a sediment source, i.e., constructional beach ridges in valley mouths. There is a noticeable lack of driftage on the marine-limit surface. Only two pieces of driftwood, one from Hall Island and the other from Koldewey Island, were retrieved after surveying numer- Figure 7. Stratigraphic section exposed in banks of western tribu- ous marine-limit landforms on central and eastern Franz Josef Land. A tary of the Romantikov River, Hayes Island (location in Fig. 5a) show- similar paucity of driftage on marine-limit surfaces was observed on west- ing postglacial emergence sequence. Each stratigraphic unit was ern Franz Josef Land (Näslund et al., 1994; Forman et al., 1996). The lack traceable for 100+ m.; asl—above sea level.

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of boulder-dominated beaches, the occurrence of sea-ice pushed ridges, lusks (Peacock, 1989). Diatom records for the Norwegian and Greenland and the scarcity of driftage on marine limit surfaces may indicate a more seas indicate a perennial sea-ice pack between ca. 13 and 10.5 ka, present permanent sea-ice cover, at least in the near-shore zone, that would sea-surface conditions prevailing by 10 ka (Koç et al., 1993). However, dampen waves and restrict the flux of flotsam during initial emergence planktonic foraminiferal records west of Svalbard indicate periodic open (Häggblom, 1982; Stewart and England, 1983). water conditions in the late glacial (Hebbeln et al., 1994). The occurrence The oldest 14C ages on driftage and shell of ca. 10 400 yr B.P. from of rare whalebones dated between 13 and 11 ka indicates episodic open- raised marine deposits on Franz Josef Land (Forman et al., 1996) provide water conditions extending to nearshore areas on west Spitsbergen (For- a minimum age on deglaciation, particularly if perennial sea ice domi- man et al., 1987; Forman, 1990). However, there is a distinct absence of nated with ice-sheet retreat. A permanent sea-ice cover would restrict the whalebone and driftwood before ca. 10 ka on northern Spitsbergen, even flux of flotsam (Häggblom, 1982; Stewart and England, 1983), the in- though strandflats formed before 11 ka indicate the absence of open- migration of whales (Moore and Reeves, 1993), and colonization by mol- water conditions conducive for the transport of drift upon deglaciation

Figure 8. Schematic cross section of raised beach sequence on Champ Island (location in Fig. 5a) showing distribution of surficial deposits and height of marine limit; asl—above sea level. Sublittoral sands with ca. 9.4 ka shells were located within 50 m of a present glacier front. These observations indicate marine invasion by the early Holocene with glaciers at or behind present margins.

Figure 9. Schematic cross section of raised beach sequence on Wiener Neustadt Island (location in Fig. 5a), showing distribution of surficial deposits and height of highest discernable raised beach; asl—above sea level. Stratigraphic relations are depicted for stream-banks eroded into raised beach sequence. Stratigraphic units are laterally traceable for 20+ m. Shells from below beach gravels yielded a 14C age of ca. 9.0 ka, indicating deglacial emergence by early Holocene time.

1124 Geological Society of America Bulletin, September 1997

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(Salvigsen and Østerhlom, 1982; Lehman, 1989). Perennial sea-ice cover 9700 to 9200 yr B.P. on shell fragments from an interlobate moraine from may have dominated northern Svalbard and Franz Josef Land during the a northern outlet of the Nordaustlandet ice cap on northeastern Svalbard. late glacial until northward propagation of regional oceanographic warm- These ages indicate that this outlet retreated at least 6 km from its current ing after 10.5 ka (Koç et al., 1993; Polyak et al., 1995). position during the early Holocene Period to allow marine incursion and Glacier cover of islands in the Barents Sea was probably reduced com- deposition of shells. On Storöya, a small island 15 km east of Nordaust- pared to present glacier limits during early Holocene time (10 to 8 ka). At landet, the inferred presence of 9 to 5 ka raised beach deposits beneath the a number of localities on Franz Josef Land, within 1 to 2 km of the pre- present ice cap marks a significant reduction or possible absence of the ice sent glacier margin, in situ shells from raised-marine sediments yield 14C cap during the early Holocene Period (Jonsson, 1983). A similar geomor- ages between 9700 and 8400 yr B.P., evidence that outlet glaciers were at phic relation was recognized on Alexandra Island, Franz Josef Land, or behind present margins by the early Holocene Period. (Figs. 8, 9 and 12; Forman et al., 1996). Blake (1989) reported AMS 14C ages of ca.

Figure 10. Height-age (asl—above sea level) relation for raised Figure 11. Height-age (asl—above sea level) relation for raised beaches on (a) Klagenfurt Island and (b) Wilczek Island. Arrests in beaches on (a) Koldewey Island and (b) Hall Island. Arrests in emer- emergence are inferred from the occurrence of escarpments and >1 gence are inferred from the occurrence of escarpments and >1 k.y. k.y. range in 14C ages for the <3 m elevational span of raised beaches. range in 14C ages for the <3 m elevational span of raised beaches. The The size of the plotting symbol approximates errors in determining size of the plotting symbol approximates errors in determining alti- altitude of approximately 1 m and 14C age determination errors of ap- tude of approximately 1 m and 14C age determination errors of approximately 100 yr. proximately 100 yr.

Geological Society of America Bulletin, September 1997 1125

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/109/9/1116/3382763/i0016-7606-109-9-1116.pdf by guest on 30 September 2021 Figure 12. Schematic cross section of a raised delta section in inner Severe Bay, Hall Island (location on Fig. 5b). Dip of the beds range from near horizontal at the base (5°) to 30° near the section top; asl—above sea level. The plunge of the beds range from 120° to 155°, indicating a sediment source from the northwest, toward the present outlet glacier margin. Radiocarbon ages on in situ paired mollusks of M. truncata place the deposition of this sequence between 9.7 and 8.0 ka.

Figure 13. Estimated uplift for Hooker and Scott Keltie islands (Forman et al., 1996) and Koldewey Island derived from emergence data corrected for a rise in eustatic sea level (Fairbanks, 1989) and calendar corrected ages (Stuiver and Reimer, 1993). Uplift data are fitted by an exponential function; quality of fit is indicated by the R2 value.

1126 Geological Society of America Bulletin, September 1997

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where raised beaches dated between ca. 8.3 and 6 ka are juxtaposed at the document either a transgression or an arrest in emergence with formation of present ice-cap margin, evidence for less glacier cover during early Holo- the marine limit (Naslünd et al., 1994; Forman et al., 1996), similar to an cene time (Glazovskiy et al., 1992). inferred stillstand with marine limit formation on Koldewey and Hall islands. The variation in marine limit height and age and the early period of POSTGLACIAL EMERGENCE AND UPLIFT relative stasis in emergence on Franz Josef Land reflects the interplay between eustasy and isostasy. Eustatic sea-level rise in the past ~20 k.y. is In this study the highest (32 to 40 m asl) and apparently oldest (8.5 to 10 from the transfer of water from ice sheets to the oceans. The isostatic response ka) marine limits are registered for Leigh Smith, Brady, and Hall islands reflects crustal upwarping with ice-sheet unloading and water loading in the (Table 2). Previously, an even higher marine limit at 49 m asl, dated to ca. adjacent seas. Emergence and initial formation of a raised beach on Franz 10 ka, was registered on Bell Island, southwestern Franz Josef Land. In Josef Land occur when the rate of isostasy exceeds the rate of eustasy. contrast, the marine limits on Heiss, Fersman, Newcombe, Wilczek, Kla- Modeling the course of uplift in the Barents Sea provides insight into genfurt, and Koldewey islands are lower (20 and 27 m asl) and apparently eustatic and isostatic controls on the course of postglacial relative sea-level. younger (6 to 8 ka ). However, shells collected from sublittoral sediments An exponential function (Up = CeKT; where Up = uplift, C = remnant upon adjacent Champa and Weiner Neustandt islands beneath littoral gravels lift, K= rate constant, and T = time) provides a first-order approximation indicate marine invasion of central Franz Josef Land by at least 9.4 ka. for the form of postglacial uplift for many areas that sustained 1000+ m Previous studies of postglacial emergence on western Franz Josef Land thick ice sheets in late Weichselian time (Andrews, 1968, 1970; Bakkelid,

TABLE 2. HOLOCENE EMERGENCE DATA AND CALCULATED UPLIFT VALUES FOR SVALBARD, NORWAY, AND FRANZ JOSEF LAND, RUSSIA Location Reference Emergence* Marine Present ÒCÓ Uplift Uplift Curve in meters since limit uplift rate¤ remnant half-life¤ k-value¤ R2 5 ka 7 ka 9 ka (m asl) (mm/yr) uplift¤ (yr) (x 10Ð4/yr) Franz Josef Land Alexandra Island Glazovskiy et al. (1992) 15 ²24 24 0.9 3.4 2670 2.6 0.93 Southeast George Island Forman et al. (1996) >20 ²38 38 1.1 3.2 2040# 3.4 0.95 Bell Island Forman et al. (1996) 20 29 45 49 0.9 2.9 2170 3.2 0.98 Northbrook Island Forman et al. (1996) 22 32 34 43 1.0 3.2 2170 3.2 0.92 Etheridge Island Forman et al. (1996) 22 28 1.0 2.8 1920# 3.6 0.99 Hooker and Scott Keltie Islands Forman et al. (1996) 18 28 30 38 0.7 2.0 2040 3.4 0.94 Koettlitz and Nansen Islands Forman et al. (1996) 20 26 28 29 1.0 4.0 2670 2.6 0.99 Leigh Smith Island 24 40 1.4 5.0 2480# 2.8 0.89 Brady Island 18 24 31 34 0.7 2.1 2040 3.4 0.98 Hayes/Fersman/Newcombe Islands 16 21 4.2 7.6 1260# 5.5 0.95 Hall Island 18 27 31 32 0.8 2.6 2170 3.2 0.97 Wilczek Island 16 26 0.9 3.5 2570# 2.7 0.96 Koldewey Island 17 23 ²24 24 0.7 1.9 1920 3.6 0.97 Klagenfurt Island 17 20 0.8 2.2 1980# 3.5 0.98 Averages# 0.8 ± 0.1 2.8 ± 0.8 2230 ± 280 3.2± 0.4

Svalbard Hornsund Birkenmajer and Olsson (1970) <5 7 ~25 Wedel Jarlsberg Land Salvigsen et al. (1991) 6 18 58 Ytterdalen, Bellsund Landvik et al. (1987) 8 27 64 Kapp Linne, Isfjorden Sandahl (1986) 5 8 28 65-75 Daudmanns¿yra Forman (1990) 4 <5 11 48 Erdmannflya and Bohemanflya Salvigsen et al. (1990) 3 5 17 55-66 Blomesletta Pewe et al. (1982) 7 12 25 62 Kapp Ekholm, Billefjorden Salvigsen (1984) 10 20 45 ~90 South Prins Karls Forland Forman (1990) 3 5 36 Br¿ggerhalv¿ya Forman et al. (1987) <5 <5 <5 45 Mitrahalv¿ya Forman (1990) <5 <5 <5 20 Reinsdyrflya Lehman (1989) <5 <5 <5 25 GrŒhuken Salvigsen and ¯sterholm (1982) <3 <3 8 >40 Mosselbukta Salvigsen and ¯sterholm (1982) <3 <3 21 >65 Northwest Nordaustlandet Blake (1961)5 10 30 ~50 Stor¿ya Island Jonsson (1983) 17 26 42 66 0.7 1.6 1820 3.8 0.99 South Nordaustlandet Salvigsen (1978) 20 29 55 70-120 0.8 1.8 1820 3.8 0.99 Kongs¿ya Salvigsen (1981), Ingolfsson et al. (1997) 31 45 69 100-120 1.6 5.5 2310 3.0 0.97 Wilhelm¿ya Hoppe (1972) 14 27 45 >45 Kapp Ziehen, Barents¿ya Mangerud et al., 1992 20 37 62 89 1.2 3.4 2100 3.3 0.99 Humlavika, Edge¿ya Mangerud et al. (1992) 22 37 59 87 1.2 3.4 2100 3.3 0.99 Diskobukta, Edge¿ya Mangerud et al. (1992) 20 35 56 85 South Edge¿ya Mangerud et al. (1992), Hoppe (1972) 23 35 53 80 Agardhbukta, Spitsbergen Salvigsen and Mangerud (1991) 17 25 38 52 0.7 1.7 1925 3.6 0.98 Hopen Island Hoppe et al. (1969), Zale and Brydsten (1993) 23 35 48 60-109 1.3 4.0 2310 3.0 0.98 Averages# 1.1 ± 0.3 3.1 ± 1.4 2055 ± 210 3.4 ± 0.3 *Observed emergence in meters for the past 5000, 7000, and 9000 radiocarbon years. Postglacial marine limit of late Weichselian or Holocene age. ¤Present uplift rate computed from the derivative of Up = CeKT, where Up is uplift, C is remnant uplift, k is a time constant, and t is time zero (Andrews, 1968). Estimated half-life of uplift calculated by t1/2 = ln2/k. Estimated error for individual uplift half-life and present uplift rate is approximately 10%, considering errors in estimated uplift (±5 m) and calendar correction (100-400 yr). #Half-life computed from uplift for the past 6000 calendar years; all other values computed for past 12 000 calendar years. **Averages computed for 12 000 calendar year uplift data . Errors at 1s derived from dispersion between individual values.

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1986). A similar formulation is used to model uplift for Franz Josef Land rise was ~55 m after 10.5 ka (Fairbanks, 1989; Peltier, 1994). To assess and eastern Svalbard, which yielded highly correlated fits (R2 = >0.90; present rates of uplift and uplift half-lives, the radiocarbon chronology for Fig. 13; Table 2). Calculations using emergence data spanning the past 10 uplift is converted to calender time (Stuiver and Reimer, 1993). k.y. are corrected to reflect total uplift by adding the estimated rise in Exponential fit of 14C -corrected uplift data for Franz Josef Land and global sea-level during this interval (Fairbanks, 1989). It is assumed that east Svalbard indicate that these areas are close to isostatic equilibrium at global sea level was stable after 6 ka (Kidson, 1982), and the total sea-level present (Fig. 13; Table 2). The uplift rate constant (K) for Franz Josef Land and eastern Svalbard is relatively uniform, yielding mean values of 3.2 ´ 10–4/yr and 3.4 ´ 10–4/yr for the past 12 000 calendar yr (Table 2). The resultant average half-life of uplift is approximately 2200 yr, similar to values for northern Canada (Andrews, 1968; Dyke et al., 1991) and Fennoscandinavia (Bakkelid, 1986; Weihe, 1996). The present maximum estimated rate of uplift for Franz Josef Land is 0.8 ± 0.1 mm/yr, with an inferred 3 to 2 m of uplift remaining (Table 2). The inferred present rate of uplift on eastern Svalbard is similar at 1.1 ± 0.3 mm/yr, with 1.5 to 5.5 m of isostasy in the future. Kongsøya, Aagardbukta on eastern Spitsber- gen, Kapp Ziehen on Barentsøya, and Humlavika on Edgeøya have the greatest inferred remaining emergence (3.4 to 5.5 m) and the present uplift rates (1.2 to 1.6 mm/yr), consistent with maximum late Weichselian glacier loads over the Barents Sea and eastern Svalbard (Salvigsen, 1981; Forman, 1990; Forman et al., 1995). The estimated contemporary maximum uplift rates of 0.7 to 1.6 mm/yr for eastern Svalbard and Franz Josef Land are consistent with the closest tide gauge measurements on northern Novaya Zemlya, Russkaya Gavan (Emery and Aubrey 1991, p. 114). Sea-level measurements for this locality in the northern Barents Sea over the past 40 yr yield a land uplift rate of 2 mm/yr. In contrast, predicted uplift residuals of 3 to 8 mm/yr (Peltier, 1996; M2 model), reflecting the rheological response from a modeled 2– 2.5-km-thick late Weichselian ice sheet over the Barents and Kara seas (Peltier, 1994, 1996), are at odds with the observed current uplift rates of ²0.7 to 2 mm/yr. The sea-level curve from Barbados currently provides the best approximation of the course of global sea level during the last deglaciation (Fair- banks, 1989). However, uncertainty remains on directly applying sea-level estimates from Barbados to the Barents Sea because of imprecise estimates on the progression of the geoid during deglaciation and gravitational effects on sea level by adjacent ice sheets (e.g., Anderson, 1984; Fjeldskaar, 1994; Mörner, 1978). To minimize uncertainties of applying an equatorial sea- Figure 14. Plot of the rate of sea-level change for 1000 14C year in- level record to the Barents Sea, the derivative of the Barbados sea-level tervals for the past 11 000 yr. Changes in eustasy are derived from curve (Fairbanks, 1989) is presented as a negative rate compared to the Fairbanks (1989). Modeled uplift rate is derived from exponential fit modeled isostatic response (Figs. 13 and 14). The average rates of eustatic of uplift data, as shown in Figure 13. Rate of modeled emergence is sea-level rise and isostatic adjustment are computed in 1000 14C year derived by subtracting rate of eustasy from rate of modeled uplift. increments for the past 10 k.y. (Fig. 14). The difference between the rate of Measured emergence rate is from an empirically derived relative sea- eustatic rise and isostatic compensation yields a predicted emergence level curve for Hooker and Scott Keltie islands (Forman et al., 1996) rate/k.y. This predicted emergence rate is then compared to the measured and for Koldewey Island (Fig. 11a). emergence rate for Hooker and Scot Keltie islands and Koldewey Island

TABLE 3. ELEVATION AND APPROXIMATE AGE OF MARINE LIMIT AND INFERRED POSTGLACIAL RELATIVE SEA-LEVEL ARRESTS ON FRANZ JOSEF LAND, RUSSIA Island foreland Marine limit Arrest 1 Arrest 2 Arrest 3 Elevation Age Elevation Age Elevation Age Elevation Age (m asl) (ka) (m asl) (ka) (m asl) (ka) (m asl) (ka) Brady 34 ± 1 >8.1 22Ð19 6.5Ð5.0 9Ð5 4.0Ð2.6 Leigh-Smith 40 ± 2 >5.1 21Ð14 4.5Ð2.5 Klagenfurt 20 ± 1 >4.9 20Ð17 >4.9 14Ð10 5.0Ð4.0(?) 6Ð4 3.2Ð1.9 Wilczek 25 ± 1 >5.9 25Ð22 >5.9 20Ð16 5.8Ð4.4 10Ð5 3.3Ð2.0 Hall 32 ± 2 >9.7 32Ð26 >9.7Ð7.0 23Ð18 6.5Ð5.0(?) 9Ð7 3.5Ð2.3 Koldewey 24 ± 1 >8.0 24Ð20 >8.0Ð6.0 18Ð16 6.0Ð5.0(?) 6Ð2 2.9Ð1.1 Hooker/Scott Keltie* 36 ± 2 ³10.3 36Ð26 10.0Ð6.6 18Ð16 6.6Ð4.6 11Ð8 4.5Ð2.2 Bell* 49 ± 2 ³9.7 12Ð8 3.9Ð2.8 Etheridge* 18Ð16 6.0Ð5.0 10Ð5 4.2Ð1.1 Koettlitz/Nansen* 29 ± 2 ³10.4 29Ð22 9.9Ð6.2 14Ð12 4.2Ð3.0 Northbrook* 42 ± 2 ³9.2 32Ð30 9.2Ð6.3 14Ð9 4.0Ð2.4 George* 38 ± 2 >6.0 *From Forman et al. (1996), Table 2.

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(derived from Fig. 11a and Forman et al., 1996, Fig. 5) to evaluate the Superimposed on the decelerating rate of uplift are second-order sea- interplay between eustasy and isostasy in the Barents Sea (Fig. 14). level oscillations expressed as two apparent arrests in emergence in the The measured emergence rate for Hooker and Scott Kelty islands and middle and late Holocene Period (Forman et al., 1996; Figs. 4, 6, 10, and Koldewey Island agrees well with modeled rates from the past 7 k.y. (Fig. 11; Table 3). These arrests are identified by the occurrence of continuous 14), consistent with the primacy of glacio-isostatic adjustment in the mid- escarpments or broad constructional beaches, and/or a >1 k.y. range of 14C dle and late Holocene for controlling the course of relative sea level in the ages obtained for similar elevations (within 3 m) of raised beach surfaces Barents Sea. However, prior to 7 ka there is a noticeable discrepancy, par- (Forman et al., 1996). Arrest 2 occurred after the formation of the marine ticularly on Hooker and Scott Keltie islands; measured emergence rates are limit and is well demarked by an escarpment, particularly on Wilczek, lower than those predicted (Fig. 14). This lower initial emergence rate on Brady, and Koldewey islands. Radiocarbon dating of driftage above, below, Franz Josef Land is reflected as a diachronous marine limit dated between and associated with the escarpment indicates a stasis in relative sea level 10.4 and 6 ka, and previously denoted as a transgression (Näslund et al., sometime between 7 and 5 ka (Table 3). The latest arrest (3) is less pro- 1994) or an arrest with a fall in relative sea level (Forman et al., 1996; Table nounced and is identified on many forelands as a broad constructional ter- 3). It is unlikely that the lower measured rates of emergence prior to 7 ka race between 4 and 8 m asl. Radiocarbon dating of driftage from this raised reflect glacier reloading, with outlet glaciers at or behind present position surface places construction of this lower surface between 4 and 2 ka. by the early Holocene. Alternatively, the reflooding of the Barents Sea after Arrest 2, ca. 6 ka, may reflect a reduction in glacio-isostatic compensation deglaciation, ca. 13 to 10 ka, may be a sufficient load to dampen glacio- with back migration of displaced mantle material. The latest arrest, ca. 3 isostatic compensation. The average present depth of the Barents Sea is 230 ka, and possibly earlier arrests may reflect an increase in the average m, and ca. 10 to 9 ka the western and central portions were approximately storm-wave height with seasonally less-extensive sea ice and greater pen- 150 to 50 m deeper because of downwarping from prior ice-sheet loading. etration of North Atlantic generated storms into the Barents Sea (Fletcher The inferred water load in the Barents Sea ca. 10 ka may be equivalent to et al., 1993). Steric and nonsteric sea level effects may have a greater in- 20% to 10% of the modeled ice-sheet load during the glacial maximum fluence on raised beach morphology, particularly in the late Holocene Pe- (Lambeck, 1995), and would have dampened the initial rate of emergence. riod, with diminishing rates (<3 mm/yr) of isostatic adjustment.

Figure 15. Postglacial emergence records for Franz Josef Land, Russia. The y-axis of each plot shows altitude (m asl), while the x-axis shows age (´103 radiocarbon years B.P.).

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PATTERN OF POSTGLACIAL EMERGENCE integrated with emergence data from Svalbard (Table 2; Fig. 17). The combination of emergence data from Franz Josef Land and Svalbard is justified There are 14 separate postglacial relative sea-level records for raised because glacio-isostatic compensation reflects past glacial loads over hun- beach sequences on Franz Josef Land (Fig. 15) that provide insight into dreds of kilometers, with a half-life response of approximately 2200 yr the distribution of past ice-sheet loads. Figure 16 shows a pattern of emer- (Table 2). This combined assessment of the pattern of postglacial emergence since 5 and 9 ka for Franz Josef Land. The northern limits of emergence for the Barents Sea places a maximum ice-sheet load over the north- gence contours are not well constrained because of the paucity of relative ern Barents Sea. The new emergence data from Franz Josef Land indicate sea-level data north of lat 80°30¢N. The available emergence data since 5 substantially less isostatic compensation over Franz Josef Land, compared and 9 ka show these raised surfaces respectively ascending toward the to eastern Svalbard (Salvigsen, 1981). Observations of a low (<20 m asl) southwest at approximately 0.1 m/km and 0.3 m/km. and young (<6 ka) postglacial marine limit on Novaya Zemlya (Forman et The emergence isobases since 5 and 9 ka for Franz Josef Land have been al., 1995) confines the maximum ice sheet load to the northern and western

Figure 16. Estimated emergence isobases since 5000 14C yr and 9000 14C yr B.P. for Franz Josef Land, Russia. Emergence values are from Figure 15.

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Barents Sea. The pattern of glacio-isostasy is inconsistent with a dominant CONCLUSIONS ice sheet load modeled over Novaya Zemlya and the Kara Sea (Peltier, 1994). The southern limit of maximum isostatic rebound in the Barents Sea Geomorphic and stratigraphic evidence place deglacial unloading of is more difficult to constrain (Fig. 17). However, there is no evidence for central Franz Josef Land prior to 9.4 ka. A previous study of emergence northerly deflection of postglacial isobases on Fennoscandinavia or the along British Channel on western Franz Josef Land indicates that emer- Kola Peninsula (Møller, 1986; Snyder et al., 1996), indicating a diminished gence commenced prior to 10.4 ka. Records from the more than 500-m- ice-sheet load and/or early deglaciation of the southern Barents Sea. deep Franz Victoria Trough, immediately east of Franz Josef Land, place Glacio-isostatic response was even more modest in the southeastern Bar- deglaciation of the adjacent Barents Sea ca. 13 ka (Polyak and Solheim, ents Sea, with marine limits registered at <10 m on southern Novaya 1994; Lubinski et al., 1996). The cessation of glacial-marine deposition Zemlya and Kolguev Island (Forman et al., 1995) and postglacial submer- and the dominance of pelagic sedimentation in the Franz Victoria Trough gence of the Pechora lowland coast (Tveranger et al., 1995). (Lubinski et al., 1996) and the southern Barents Sea (Polyak et al., 1995)

Figure 17. Estimated emergence isobases for the Barents Sea area since 5000 14C yr and 9000 14C yr B.P. Circles indicate data points. Data for Franz Josef Land are shown in Figure 16; those for Novaya Zemlya are from Forman et al. (1995), and those for Svalbard are listed in Table 2.

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by ca. 10 ka place ice-sheet withdrawal from the Barents Sea prior to the sund, Spitsbergen, and the problem of land uplift: Norsk Polar Institute Årbok 1969, p. 2-43. Holocene Period. Deglacial ages at the inferred interior of the Barents Sea Blake, W., Jr., 1961, Radiocarbon dating of raised beaches in Nordaustlandet, Spitsbergen, in: ice sheet from Edgeøya of ca. 10.3 ka (Landvik et al., 1992), Franz Josef Raasch, G. O., ed., The Geology of the Arctic: Toronto, Canada, University of Toronto Land of ca. 10.4 ka (Forman et al., 1996) and minimum limiting ages of ca. Press, p. 133-145. Blake, W. J., 1989, Radiocarbon dating by accelerator mass spectrometry: A contribution to the 9.7 ka for emergence on Kongsøya (Salvigsen, 1981), Storøya (Jonsson, chronology of Holocene events in Nordaustlandet, Svalbard: Geografiska Annaler, 1983), and Hopen (Zale and Brydsten, 1993), indicate final demise of ter- v. 71(A), p. 51-74. Cathles, L. M., 1975, The viscosity of the Earth’s mantle: Princeton, New Jersey, Princeton restrial portions of the eastern Barents Sea ice sheet by 10 ka. The apparent University Press, 287 p. difference in timing of deglaciation between the Franz Victoria Trough and Denisov, V. V., Matishov, D. G., and Sokolov, V. T., 1993, Hydrometeorological conditions of adjacent Franz Josef Land may reflect the early (12 to 13 ka) retreat of an the Franz Josef Land Archipelago, in Environment and Ecosystems of the Franz Josef Land (Archipelago and Shelf): Apatity, Russia, Kola Science Center of the Russian Acad- outlet glacier in a deep trough bordering the Barents Sea, whereas an ice emy of Sciences p. 26-36. cap was maintained on adjacent Franz Josef Land until ca. 10.5 ka. Alter- Dibner, V. D., 1965, The history of late Pleistocene and Holocene sedimentation in Franz Josef natively, deglacial ages from the raised-marine record on Franz Josef Land Land: Scientific Research Institute of the Geology of the Arctic Transactions, v. 143, p. 300-318. may be minimums. Marine incursion into Franz Josef Land may have Dyke, A. S., Morris, T. F., and Green, D. E. C., 1991, Postglacial tectonic and sea level history occurred earlier (ca. 12 to 11 ka), but permanent sea-ice cover within the of the central Canadian arctic: Geological Survey of Canada Bulletin, v. 397, p. 1-56. Elverhøi, A., Andersen, E. S., Dokken, T., Hebblen, D., Spielhagen, R., Svendsen, J.-I., Sor- archipelago would restrict the colonization by mollusks and the transport flaten, M., Rornes, A., Hald, M., and Forsberg, C. F., 1995, The growth and decay of the of wood and whalebone until after 10.4 ka, when regional sea-surface con- Late Weichselian ice sheet in western Svalbard and adjacent areas based on provenance ditions were similar to present conditions (Koç et al., 1993; Polyak et al., studies of marine sediments: Quaternary Research, v. 44, p. 303-316. Emery, K. O., and Aubrey, D. G., 1991, Sea levels, land levels, and tide gauges: New York, 1995). Glacier coverage was at a minimum on Franz Josef Land and on Springer-Verlag, 237 p. eastern Svalbard by ca. 9.5 to 8.5 ka (Blake, 1989; Jonsson, 1983). Fairbanks, R. G., 1989, A 17,000 year glacio-eustatic sea-level record: Influence of glacial melt- The altitude of the marine limit on Franz Josef Land ranges from 49 to ing on the Younger Dryas event and deep-ocean circulation: Nature, v. 342, p. 637-642. Fjeldskaar, W., 1994, The amplitude and decay of the glacial forebulge in Fennoscandia: Norsk 20 m asl and is low compared to eastern Svalbard (110 to 60 m asl). The Geologisk Tidsskrift, p. 74, p. 2-8. marine limit was formed sometime between ³10.4 ka and 6.5 ka and Fletcher, C. H. I., Fairbridge, R. W., Moller, J. J., and Long, A. J., 1993, Emergence of the Varanger Peninsula, Arctic Norway, and climate changes since deglaciation: Holocene, exhibits greater diachrony where emergence is <35 m. This slow initial rate v. 3, p. 116-127. of emergence reflects glacio-isostatic compensation offset by global sea- Forman, S. L., 1990, Post-glacial relative sea-level history of northwestern Spitsbergen, Sval- level rise and perhaps an additional component from renewed water load- bard: Geological Society of America Bulletin, v. 102, p. 1580-1590. Forman, S. L., and Polyak, L., 1997, Radiocarbon content of pre-bomb marine mollusks and ing of the Barents Sea after deglaciation. The presence of raised beaches at variations in the 14C reservoir age for coastal areas of the Barents and Kara Seas, Russia: 1 to 4 m asl dated as 1 to 2 ka indicates that uplift is incomplete. An expo- Geophysical Research Letters, v. 24, p. 885–888. nential extrapolation of uplift data for Franz Josef Land and eastern Sval- Forman, S. L., Mann, D., and Miller, G. H., 1987, Late Weichselian and Holocene relative sea- level history of Brøggerhalvøya, Spitsbergen, Svalbard Archipelago: Quaternary bard yield current maximum uplift rates of 0.7 to 1.6 mm/yr, as much as Research, v. 27, p. 41-50. 5.5 m of uplift remaining. These values are at least 50% to 80% lower than Forman, S. L., Lubinski, D., Miller, G. H., Snyder, J., Matishov, G., Korsun, S., and Myslivets, V., 1995, Post-glacial emergence and distribution of late Weichselian ice sheet loads in the estimated uplift residual for an ice-sheet model for the Barents and the northern Barents and Kara Seas, Russia: Geology, v. 23, p. 113-116. Kara seas (Peltier, 1994, 1996). This discrepancy between modeled and Forman, S. L., Lubinski, D., Miller, G. H., Matishov, G. G., Korsun, S., Snyder, J., Herlihy, F., measured uplift rates indicates that this ice sheet model may overestimate Weihe, R., and Myslivets, V., 1996, Postglacial emergence of western Franz Josef Land, Russia and retreat of the Barents Sea ice sheet: Quaternary Science Reviews. past glacier loads and inaccurately portray deglacial history, and/or that Glazovskiy, A. N., Näslund, J.-O., and Zale, R., 1992, Deglaciation and shoreline displacement parameters for mantle viscosity need additional adjustment (Peltier, 1996). of Alexandra Land, Franz Josef Land: Geografiska Annaler, v. 74A, p. 283-293. The compilation of emergence data from Franz Josef Land, Svalbard, and Grosswald, M. E., 1973, Glaciers of Franz Josef Land: Moscow, Nauka, 351 p. Hafsten, U., 1983, Shore-level changes in south Norway during the last 13,000 years traced by Novaya Zemlya (Forman et al., 1995) confines the maximum area of glac- biostratigraphical methods and radiometric dating: Norsk Geografiska Tidsskrift, v. 37, ier loading to the Barents Sea, with an order of magnitude lower glacio- p. 63-79. Häggblom, A., 1982, Driftwood in Svalbard as an indicator of sea ice conditions: Geografiska isostatic compensation on Novaya Zemlya and the southeastern Barents Annaler, v. 64A, p. 81-94. Sea. Emergence isobases since 5 and 9 ka descend northward across Franz Hebbeln, D., Dokken, T., Andersen, E. S., Hald, M., and Elverhøi, A., 1994, Moisture supply Josef Land, indicating a diminishing glacier load into the Arctic Ocean. for northern ice-sheet growth during the last glacial maximum: Nature, v. 370, p. 357-360. Hoppe, G., 1972, Ice sheets around the Norwegian Sea during the Würm Glaciation, in Dahl, E., Strømborg, A., and Tandberg, O. G., eds., The Norwegian Sea region, its hydrography, ACKNOWLEDGMENTS glacial and biological history: Ambio Special Report, 2, p. 14 - 19. Hoppe, G., Schytt, V., Haggblom, A., and Østerholm, H., 1969, Studies of the glacial history of Hopen (Hopen Island), Svalbard: Geografiska Annaler, v. 51(A), p. 185 -192. National Science Foundation grants DPP-9001471, OPP-9222972, and Ingólfsson, O. Rognvaldsson, F., Bergsten, H., Hedenas, L., Lemdahl, G., Lirio, J. M., and OPP-9223493 and Office of Naval Research contract N00014-92-M-0170 Sejrup, H. P., 1997, Late Quaternary glacial and environmental history of Kongsøya, Svalbard: Polar Research , v. 14 (in press). supported this research. We thank the crew of R/V Dalnie Zelentsy, T. Jull Jonsson, S., 1983, On the geomorphology and past glaciation of Storöya, Svalbard: at the University of Arizona for AMS 14C ages, and J. Jarros for drafting Geografiska Annaler, v. 65A, p. 1-17. efforts. We also thank J. Brigham-Grette, W. D. McCoy, and W. R. Peltier Kidson, C., 1982, Sea level changes in the Holocene: Quaternary Science Reviews, v. 1, p. 121-151. Koç, N., Jansen, E., and Haflidason, H., 1993, Paleoceanographic reconstructions of surface for reviews. ocean conditions in the Greenland, Iceland and Norwegian Seas through the last 14 ka based on diatoms: Quaternary Science Reviews, v. 12, p. 115-140. Koettlitz, R., 1898, Observations on the Geology of Franz Josef Land: Geological Society REFERENCES CITED [London] Quarterly Journal, v. 54, p. 620-645. Lambeck, K., 1995, Constraints on the Late Weichselian ice sheet over the Barents Sea from Anderson, J. A., 1984, Geophysical interpretation of features in the marine geoid of Fennoscan- observations of raised shorelines: Quaternary Science Reviews, v. 14, p. 1-16. dia: Marine Geophysical Research, v. 7, p. 191-203. Landvik, J. Y., Mangerud, J., and Salvigsen, O., 1987, The Late Weichselian and Holocene shore- Andrews, J. T., 1968, Postglacial rebound in Arctic Canada: Similarity and prediction of uplift line displacement on the west-central coast of Svalbard: Polar Research v. 5, p. 29-44. curves: Canadian Journal of Earth Sciences, v. 5, p. 39-47. Landvik, J. Y., Hansen, A., Kelly, M., Salvigsen, O., Slettemark, Ø., and Stubrup, O. P., 1992, The Andrews, J. T., 1970, A geomorphical study of post-glacial uplift with particular reference to last deglaciation and glacimarine/marine sedimentation on Barentsøya and Edgeøya, eastern Arctic Canada: London, Institute of British Geographers, 156 p. Svalbard: LUNDQUA Report, v. 35 p. 61-84. Bakkelid, S., 1986, The determination of rates of land uplift in Norway: Tectonophysics, v. 130, Lehman, S. J., 1989, Late Quaternary glacial and marine paleo-environments of northwest p. 307-326. Spitsbergen, Svalbard [Ph.D. dissert.]: Boulder, University of Colorado, 236 p. Birkenmejar, K., and Olsson, I. U., 1970, Radiocarbon dating of raised marine terraces at Horn- Lubinski, D. J., Korsun, S., Polyak, L., Forman, S. L., Lehman, S. J., Herlihy, F. A., and Miller,

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G. H., 1996, The last deglaciation of the Franz Victoria Trough, northern Barents Sea: consequences for the glacial history of the Barents Sea area: Geografiska Annaler, v. 63A, Boreas, v. 25, p. 89-100. p. 283-292. Mangerud, J., and Gulliksen, S., 1975, Apparent radiocarbon ages of recent marine shells from Salvigsen, O., 1984, Occurrence of pumice on raised beaches and Holocene shoreline dis- Norway, Spitsbergen, and Arctic Canada: Quaternary Research, v. 5, p. 263-273. placement in the inner Isfjorden area, Svalbard: Polar Research, v. 2 , p. 107 -113. Mangerud, J., Bondevik, S., Ronnert, L., and Salvigsen, O., 1992, Shore displacement and Salvigsen, O., and Mangerud, J., 1991, Holocene shoreline displacement at Agardhbukta, east- marine limits on Edgeøya and Barentsøya, eastern Svalbard, LUNDQUA Report, v. 35, ern Spitsbergen, Svalbard: Polar Research, v. 9, p. 1 -7. p. 51 - 60. Salvigsen, O., and Østerholm, H., 1982, Radiocarbon dated raised beaches and glacial history Martini, P. I., 1981, Ice effect on erosion and sedimentation on the Ontario shores of James Bay, of the northern coast of Spitsbergen, Svalbard: Polar Research, v. 1, p. 97-115. Canada: Zeitschrift für Geomorphologie, v. 25, p. 1-16. Salvigsen, O., Elgersma, A., Hjort, C., Lagerlund, E., Liestol, O., and Svensson, N.-O., 1990, Matishov, G., Cherkis, N., Vermillion, M. S., and Forman, S. L., 1995, Bathymetry of the Franz Glacial history and shoreline displacement on Erdmannflya and Bohemanflya, Spitsber- Josef Land Region, northeast Barents Sea, Russia: Geological Society of America Map gen, Svalbard: Polar Research, v. 8, p. 261 - 273. and Chart Series MCH080, scale 1:500 000, 1 sheet. Salvigsen, O., Elgersma, A., and Landvik, J. Y., 1991, Radiocarbon dated raised beaches in Møller, J. J., 1986, Holocene transgression maximum about 6000 years B.P. at Ramså, northwestern Wedel Jarlsberg Land, Spitsbergen, Svalbard: Lublin, Poland, Wyprawy Vesteralen, North Norway: Norsk Geologisk Tiddskrift v. 40, p. 77-84. Geograficzne na Spitsbergen, p. 9 - 16. Moore, S. E., and Reeves, R. R., 1993, Distribution and movement, in Burns, J. J., and Mon- Sandahl, T., 1986. Kvartaergeologisk undersøkelser i omradet Lewinodden–Kapp tague, J. eds., The Bowhead whale, Balaena mysticetus: Society for Marine Mammalogy Starostin–Linnevatnet, Ytre Isfjord [thesis]: University of Bergen, Norway, 112 p. Special Publication 2, p. 313-386. Siegert, M. J., and Dowdeswell, J. A., 1995, Numerical modeling of the late Weichselian Sval- Mörner, N-A., 1978, Eustasy and geoid changes as a function of core/mantle changes, in bard-Barents Sea ice sheet: Quaternary Research, v. 43, p. 1-13. Mörner, N-A., ed., Earth Rheology, Isostasy, and Eustasy: New York, John Wiley & Sons, Snyder, J. A., Korsun, S. A., and Forman, S. L., 1996, Postglacial emergence and the tapes p. 251-284. transgression, north-central Kola Peninsula, Russia: Boreas. Näslund, J.-O., Zale, R., and Glazovskiy, A., 1994, The mid Holocene transgression on Alexan- Stewart, T. G., and England, J., 1983, Holocene sea-ice variations and paleoenvironmental dra Land, Franz Josef Land, Russia: Geografiska Annaler, v. 76(A), p. 97-101. change, northernmost Ellesmere Island, N.W.T.: Arctic and Alpine Research, v. 15, p. 1-17. Olsson, I., 1980, Content of 14C in marine mammals from northern Europe: Radiocarbon, v. 22, Stuiver, M., and Reimer, P. J., 1993, Extended 14C data base and revised CALIB 3.0 14C age p. 662-675. calibration program: Radiocarbon, v. 35, p. 215-230. Peacock, J. D., 1989, Marine mollusks and late Quaternary environmental studies with partic- Svendsen, J. I., and Mangerud, J., 1987, Late Weichselian and Holocene sea-level history for a ular reference to the late-glacial period in northwest Europe: A review: Quaternary cross-section of western Norway: Journal of Quaternary Science, v. 2, p. 113-132. Science Reviews, v. 8, p. 179-192. Svendsen, J. I., Mangerud, J. M., Elverhøi, A., Solheim, A., and Schuttenhelm, R. T. E., 1992, Peltier, W. R., 1974, The impulse response of a Maxwell Earth: Review of Geophysics, v. 12, The Late Weichselian glacial maximum on western Spitsbergen inferred from offshore p. 649-669. sediment cores: Marine Geology, v. 104, p. 1-17. Peltier, W. R., 1994, Ice Age paleotopography: Science, v. 265, p. 195-201. Tushingham, A. M., and Peltier, W. R., 1991, Validation of the ICE-3G model of Würm/ Peltier, W. R., 1996, Mantle viscosity and ice-age ice sheet topography: Science, v. 273, Wisconsin deglaciation using a global data base of relative sea level histories: Journal of p. 1359-1364 Geophysical Research, v. 97, p. 3285-3304. Pewe, T. L., Rowan, D. E., Pewe, R. H., and Stuckenrath, R., 1982, Glacial and Periglacial Tveranger, J., Astakhov, V., and Mangerud, J., 1995, The margin of the last Barents-Kara ice geology of northwest Blomesletta peninsula, Spitsbergen, Svalbard: Norsk Polarinstitut sheet at Markhida, northern Russia: Quaternary Research, v. 44, p. 328-340. Skrifter, v. 177, 32 p. Weihe, R., 1996, Late Quaternary glacial geology and relative sea level history of Franz Josef Polyak, L., and Solheim, A., 1994, Late- and post-glacial environments in the northern Barents Land, Russia: [Master’s thesis]: Columbus, Ohio State University, p. 159. Sea west of Franz Josef Land: Polar Research, v. 13, p. 197-207. Zale, R., and Brydsten, L., 1993, The pre-Holocene marine limit on Hopen, Svalbard: Boreas, Polyak, L., Lehman, S. J., Gataullin, V., and Jull, A. J. T., 1995, Two-step deglaciation of the v. 22, p. 159-164. southeastern Barents Sea: Geology, v. 23, p. 567-571. Salvigsen, O., 1978, Holocene emergence and finds of pumice, whalebones and driftwood at MANUSCRIPT RECEIVED BY THE SOCIETY MAY 10, 1996 Svartknausflya, Nordaustlandet: Norsk Polarinstitutt Årbok 1977, p. 217-228. REVISED MANUSCRIPT RECEIVED NOVEMBER 25, 1996 Salvigsen, O., 1981, Radiocarbon dated raised beaches in Kong Karls Land, Svalbard and their MANUSCRIPT ACCEPTED JANUARY 21, 1997

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