Deglaciation chronology of the Pandivere and Palivere ice-marginal zones in Estonia

Geo log i cal Quar terly, 2012, 56 (2): 353–362 DOI: http://dx.doi.org/10.7306/gq.1027

Deglaciation chro nol ogy of the Pandivere and Palivere ice-mar ginal zones in Es to nia

Leili SAARSE, Atko HEINSALU and Siim VESKI

Saarse L., Heinsalu A. and Veski S. (2012) – Deglaciation chro nol ogy of the Pandivere and Palivere ice-mar ginal zones in Es to nia. Geol.

Quart., 56 (2): 353–362, doi: 10.7306/gq.1027

Ac cel er a tor mass spec trom e try (AMS) ¹⁴C dates, pol len and plant macrofossil ev i dence and lithostratigraphic pa ram e ters ob tained from four Late Gla cial lake sed i ment re cords were used to study the deglaciation chro nol ogy of Es to nia. AMS dates show that the north ern part of the Saadjärv Drum lin Field was free of ice cover at ap prox i mately 14,300–14,200 cal yr BP. These ages fit well with the ice re treat es ti - ma tions (14,700–14,500 cal yr BP) of the Otepää ice-mar ginal zone in the south and the deglaciation of the Pandivere Up land in the north (13,800 cal yr BP). Glaciolacustrine sed i ments of the Haljala and Udriku bas ins were de pos ited in proglacial lake A1, a north east ern bay of the Bal tic Ice Lake that al ready ex isted ca. 13,800 cal yr BP. The Palivere ice-mar ginal zone, and proglacial lake A2 as so ci ated with it, was formed ca. 500 years later, at ap prox i mately 13,200 cal yr BP. New ev i dence in di cates that ice re advance dur ing the Palivere stade ter mi nated dur ing the AllerÝd chronozone.

Leili Saarse, Atko Heinsalu and Siim Veski, In sti tute of Ge ol ogy at Tallinn Uni ver sity of Tech nol ogy, Ehitajate tee 5, 19086 Tallinn, Es - to nia; e-mails: saarse@gi.ee, heinsalu@gi.ee, veski@gi.ee (re ceived: June 20, 2011, ac cepted: March 29, 2012; first pub lished on line:

June 12, 2012).

Key words: deglaciation, Late Gla cial, proglacial lakes, AMS ¹⁴C ra dio car bon dates, Es to nia.

INTRODUCTION

The deglaciation pat tern of the Scan di na vian Ice Sheet (SIS) is well-re con structed in Es to nia and a gen eral pic ture of the dif fer ent stadials and interstadials has been pre sented (e.g., Raukas et al., 1971; Kalm, 2011). The Haanja, Otepää, Sakala, Pandivere and Palivere ice-mar ginal zones have been dif fer en - ti ated (Fig. 1A) ac cord ing to more or less prom i nent landform com plexes that may in di cate mi nor stand stills and os cil la tions of the ice mar gin dur ing the ice re treat of the SIS. In pre vi ous Late Gla cial strati graphic stud ies of Es to nia, chronostra - tigraphy was mostly based on palynological re cords (Pirrus, 1969; Pirrus and Ráuk, 1979; Pirrus and Raukas, 1996) and cor re la tion with the Fennoscandian chronostratigraphical chart (Mangerud et al., 1974). How ever, the chro nol ogy of deglaciation is still de bated, as dif fer ent dat ing meth ods, in - clud ing OSL, cosmogenic ¹⁰Be dat ing and varvochronology have pro duced ages with large un cer tain ties (Raukas, 2004, 2009; Kalm, 2006). For ex am ple, the OSL dates from glacio - fluvial de pos its (Raukas and Stankowski, 2005) and ¹⁰Be dates from er ratic boul ders have given ages that dif fer by thou sands of years (Rinterknecht et al., 2006).

There fore, track ing the pre cise tim ing of the SIS mar gin re - treat in Es to nia faces many chal lenges. The scar city of or ganic ma te rial in the Late Gla cial sed i ments lim its the ap pli ca bil ity of the con ven tional ra dio car bon method to es tab lish ing re li able ice re ces sion chro nol o gies. The im ple men ta tion of the AMS

14C method, which sig nif i cantly re duces the quan tity of car bon re quired for ob tain ing ra dio car bon dates, opened up new pos si - bil i ties for dat ing ter res trial macrofossils pre served in minerogenic Late Gla cial sed i ments. Dur ing the last de cade, this method was widely used in the Bal tic re gion for con strain ing Late Gla cial chronostratigraphy and ice re ces sion chro nol ogy (StanèikaitÅ et al., 2002, 2004, 2008; Láugas et al., 2002;

Heikkilä et al., 2009; Saarse et al., 2009; Amon and Saarse, 2010; Kihno et al., 2011; Amon et al., 2012). How ever, it should be taken into con sid er ation that ra dio car bon ages ob tained from the basal sed i ment lay ers that are pre served in lake de pres sions do not di rectly date the deglaciation but merely in di cate the min i - mum time when the area be came ice-free. There can be a time lag be tween the ice mar gin re treat and the start of sed i men ta tion in bas ins, as well as in the on set of veg e ta tion colo nis ation and or ganic pro duc tion. Pi o neer veg e ta tion, how ever, may be quickly es tab lished on min eral sub strates that are ex posed af ter ice-mar gin re ces sion. The pri mary plant suc ces sion on re cently

deglaciated fore lands in the high arc tic has shown that veg e ta tion colo nises newly ex posed sur faces within the first de cade af ter ice re treat (Jones and Henry, 2003). Thus, dat ing ter res trial plant macrofossils from the basal parts of Late Gla cial lake sed i ments to es tab lish an ice re ces sion chro nol ogy may add in de pend ent data to our knowl edge.

The aim of the cur rent study was to high light the ice re ces - sion pat tern in North Es to nia on the ba sis of newly ob tained ab - so lute ages from four Late Gla cial sites: Prossa, Udriku, Haljala and Tádva. The south ern most site, the Lake Prossa se - quence, is lo cated be tween the Otepää and Pandivere ice-mar - ginal zones. The Udriku site is sit u ated within the Pandivere ice-mar ginal zone, the Haljala site on the north ern slope of the Pandivere Up land and the Tádva site be yond the Palivere ice-mar ginal zone (Fig. 1A). Prior to our stud ies, only one AMS ra dio car bon date was avail able from the Late Gla cial basal de pos its of the Saadjärv Drum lin Field (Sohar and Meidla, 2009), and none were avail able from the Late Gla cial de pos its re lated to the Palivere zone. All these sites have been stud ied, and the orig i nal ma te rial has been pub lished in dif fer - ent pa pers (Saarse et al., 2009; Amon and Saarse, 2010; Kihno et al., 2011; Saarse, 2011). In the cur rent pa per, we syn the sise the re sults of these stud ies and pres ent an over all ice re ces sion chro nol ogy for the three main ice-mar ginal zones in Es to nia.

MATERIAL AND METHODS

Pol len, macrofossils, grain size, loss-on-ig ni tion (LOI), mag netic sus cep ti bil ity (MS) and AMS ¹⁴C dates were ap plied in over lap ping cores ex tracted with a one-m-long Rus sian peat sam pler. The cores were de scribed and pho to graphed in the field, packed into plas tic semitubes, wrapped in poly eth yl ene film, trans ported to the lab o ra tory and stored in a cool room.

1 cm thick subsamples for LOI anal y ses were taken con tin u - ously, and 1 cm thick sam ples were taken for grain-size dis tri -

bu tion at 2–10 cm in ter vals. Bulk sam ples for LOI were weighed, dried at 105^oC over night, and combusted at 525 and 900^oC to cal cu late mois ture, or ganic mat ter (OM), car bon ate and minerogenic com pounds (Fig. 2). The grain-size dis tri bu - tion was ana lysed us ing an LA-950V2 la ser scat ter ing par ti cle size dis tri bu tion analyser which mea sures grain size within the range of 0.01 mm to 3 mm and dis tin guishes 89 frac tions. To avoid grain floc cu la tion, the sam ples were pre-treated with a 1% so lu tion of Na4P2O7 ´ 10(H2O). MS was mea sured with a Bartington In stru ments MS2E high-res o lu tion sur face scan - ning sen sor along care fully cleaned flat sur faces of fresh sed i - ments, which were cov ered by a thin plas tic film, at a res o lu tion of 1–2 cm. Subsamples for the pol len anal y ses (1–2 cm³) were pre pared ac cord ing to Berglund and Ralska-Jasiewiczowa (1986). The minerogenic sam ples were treated with con cen - trated HF. Lycopodium tab lets were added to cal cu late the pol - len con cen tra tion and ac cu mu la tion rates (Stockmarr, 1971).

Macrofossils were ex tracted by soak ing the 5 cm thick sam ples (160–300 cm³, mostly 210–220 cm³) in the wa ter and Na4P2O7

so lu tion and were sieved through a 0.25 mm mesh. The plant re mains were iden ti fied un der a bin oc u lar mi cro scope. The LOI di a grams were plot ted with the TILIA and TGView pro - grams (Grimm, 2007). The AMS ¹⁴C dates from mainly ter res - trial plant re mains were ob tained at the Poznañ and Uppsala ra - dio car bon lab o ra to ries (Ta ble 1) and were cal i brated and given in cal en dar years us ing the cal i bra tion dataset from Reimer et al. (2004) and the CALIB 5.0.1 soft ware (Stuiver et al., 2005).

RESULTS BY SITE

Lake Prossa (58^o38´57´´N, 26^o34´40´´E) is a mesotrophic lake that is 24.2 ha in area and is lo cated in the north west ern part of the Saadjärv Drum lin Field at 61 m above sea level (a.s.l.) (Fig. 1). The lake sur round ings can be de scribed as a land scape with large NW–SE-ori en tated drum lins. The lake it -

Fig. 1A – lo ca tion of sites stud ied with in di ca tion of the ice-mar ginal zones dis cussed in the text, the Sakala zone is poorly de fined and not in di cated; B – ice mar gin po si tion dur ing the Pandivere stage with indicating the dis tri bu tion of the A1 proglacial lake

about 13 800 cal yr BP, re con struc tion by Rosentau (2009) with au thors´ improvements

self is shal low, with peaty shores cov ered by a float ing mat.

The ba sin mor phol ogy re sem bles that of a re versed drum lin.

The cross-sec tions along the Prossa ba sin show a rather even min eral bot tom to pog ra phy (Saarse, 1994) filled with till, varved clay, sandy and clayey silt with plant de tri tus, gyttja and cal car e ous gyttja (Fig. 2A), form ing a sed i men tary se quence of gla cial, glaciolacustrine and lac us trine beds.

The low er most part of the core stud ied (760–745 cm) con - sists of mas sive sandy silt with a rel a tively high abun dance of sand frac tion that re sem bles till de pos its. This unit is cov ered by dis tinctly varved clay (745–708 cm; Fig. 2A), of which 29 an nual varves have been en coun tered. The varved clay unit is over lain by an 8 cm thick mas sive clayey silt (708–700 cm) and lam i nated cal car e ous clayey silt (700–650 cm), which in - cludes ir reg u lar, ob vi ously pyritised black stripes (Fig. 3).

The OM con tent in clayey sed i ments is scant, but the car bon - ate con tent reaches 24% (Fig. 2A). Be tween 650 and 630 cm the sand frac tion in creases (Fig. 4A). The pol len as sem blages and the find ings of Dryas octopela leaves and Betula nana seeds in the above-men tioned sed i ments sug gest a sparsely veg e tated sub arc tic tun dra land scape (Kihno et al., 2011).

The lithostratigraphic bound ary be tween the sandy silt and silt at 630 cm is rich in plant re mains, and it marks the iso la - tion of the Prossa ba sin from the large proglacial lake at the be gin ning of the AllerÝd (Kihno et al., 2011). Silt and clayey silt ac cu mu lated in the iso lated lake. In the sed i ments of Youn ger Dryas age, moss-rich lay ers are ap par ent, in clud ing Drepanocladus, in di cat ing a cold, oligotrophic clear-wa ter en vi ron ment. A re mark able change in sed i ment com po si tion is found at the core depth of 550 cm. This changes cor re lates with the Late Gla cial/Ho lo cene bound ary and marks a hi a tus in the sed i ment core caused by a low er ing of the wa ter level (Kihno et al., 2011).

Udriku Suurjärv is a small (23.7 ha) and shal low (6.8 m) lake (59^o22´17´´N, 25^o55´50´´E) on the Pandivere Up land be - tween esker ridges at an al ti tude of 95.1 m a.s.l. (Fig. 1). The hummocky and roll ing land scape on the lake catch ment, with a height reach ing 115 m a.s.l., is mainly com posed of sand and gravel, while the sur round ing low land is cov ered by peat de - pos its. The peaty lake shores are strongly abraded, and pine trunks and peat cover the nar row NW lit to ral zone. The lake ba sin is filled with lam i nated clayey silt, silt with plant re mains and silty gyttja, rep re sent ing glaciolacustrine and lac us trine palaeoenvironments.

The bot tom most lam i nated clayey silt (828–800 cm) re - sem bles varved clay. The OM and car bon ate con tent is low (Fig. 2B), and the clay frac tion is rel a tively high, reach ing 27%

(Fig. 4B). This por tion of the sed i ment is poor in macroremains, con tain ing mostly Salix po laris leaves (Amon and Saarse, 2010). A sharp in crease in the sand frac tion from 16 to 31% at 800 cm ob vi ously cor re sponds to the iso la tion of the Udriku ba sin from the Bal tic Ice Lake at ap prox i mately 13,600 cal yr BP (Amon and Saarse, 2010). In sandy silt and silt (800–755 cm), the OM con tent in creases, as do macroremains, dom i nated by Dryas octopetala and Ranunculus sect Batrachium and Nitella oo spores re mains sug gest ing in creased sum mer tem per a tures dur ing the late AllerÝd (Amon and Saarse, 2010). In the over ly ing silt, at a core depth be tween 755 and 678 cm, the sed i ment con tains dis -

persed OM and sparse plant re mains. Due to the Youn ger Dryas cool ing, the abun dance and di ver sity of macrofossils de - clined. The pol len ev i dence shows tree less tun dra con di tions through out the Late Gla cial part of the sed i ment se quence. The ac cu mu la tion rate of tree pol len was fairly low, and var i ous herbs dom i nate the lo cal flora. At the Late Gla cial/Ho lo cene bound ary be tween 680 and 670 cm, the sed i ment rap idly changes into or ganic-rich gyttja, and fos sil ev i dence shows de - vel op ing for ests.

Palaeolake Haljala (59°25´27´´N, 26°17´42´´E) is lo cated on the north ern slope of the Pandivere Up land at an el e va tion of 67–68 m a.s.l. (Fig. 1). The an cient lake was ap prox i mately 4.6 km long and 200 m wide and was dammed by a spit. Dur ing the A1 phase of the Bal tic Ice Lake (BIL), Haljala served as an an cient la goon (Saarse et al., 2009). The ba sin is filled with gla - cial, glaciolacustrine and lac us trine sed i ments. This for mer lake has been re claimed and trans formed into grass land.

The LOI re sults of the Late Gla cial sed i ments are quite sim - i lar to those of Udriku, be ing poor in OM and car bon ates (Fig. 2C); how ever, they dif fer in grain-size com po si tion, con - tain ing more clay and less sand frac tion (Fig. 4C). The sed i - ments be tween 500 and 220 cm were de pos ited in a proglacial en vi ron ment, the up per most part in the iso lated lake, which was paludified in the early Ho lo cene. In the Late Gla cial sed i ment, Dryas octopetala and Salix sp. leaves, Ranunculus sect Batrachium seeds, Betula nana, Helianthemum and other plant macroremains and pol len typ i cal the Late Gla cial en vi ron ment have been iden ti fied, but not wood re mains, in di cat ing tree less tun dra veg e ta tion (Saarse et al., 2009). The pol len re cord from the Late Gla cial por tion of the sed i ment shows a high fre - quency of Pinus pol len, which was ob vi ously trans ported over long dis tances. How ever, the Betula humilis seed in the sed i - ments dated to 13,800 cal yr BP sug gests the pos si bil ity that in - di vid ual birch trees could have colo nised the lake catch ment (Saarse et al., 2009).

Palaeolake Tádva (59°16´36´´N, 26°43´55´´E) be longs to the Palivere ice-mar ginal zone. This lake is lo cated 12 km south of Tallinn at an al ti tude of 37–37.5 m a.s.l., cov er ing an area of 1130 ha. The ba sin was flooded by wa ters of the BIL and the Yoldia Sea (Heinsalu and Veski, 2007), which left clayey silt and sand in its basal part (Fig. 2D). Later, these sed i ments were cov ered by lac us trine lime and peat. The ba sin out line is wind - ing, and the bot tom to pog ra phy is un even, with sev eral deeper hol lows where re sid ual lakes per sisted and lac us trine lime de - pos ited up to the end of the At lan tic chronozone be fore fill ing and peat bog for ma tion (Veber, 1969).

The low er most sandy silt (520–510 cm) is over lain by blu - ish-grey mas sive clayey silt (510–478 cm) with low OM and car - bon ate con tent (Figs. 2D and 4D). The sandy silt be tween 478 and 447 cm has a rhyth mic pat tern (Fig. 3) and in cludes scat tered mol - lusc shells fol lowed up wards by lac us trine lime al ter nat ing with blu ish silt, which grad u ally turns to lac us trine lime. The OM con - tent is very low through out the stud ied se quence, but the car bon ate con tent in creases in the top most part of the se quence (Fig. 2D).

The Tádva ba sin iso lated slowly be tween 11,600 and 11,400 cal yr BP. Ac cord ing to the pol len anal y ses (Veber, 1969) and AMS chro nol ogy (Ta ble 1), the sed i men ta tion of silt started at the end of the AllerÝd and ter mi nated dur ing the Preboreal.

Deglaciation chronology of the Pandivere and Palivere ice-marginal zones in Estonia 355

CHRONOLOGY OF DEGLACIATION – DISCUSSION

Ac cord ing to re cent es ti ma tions, the Saadjärv Drum lin Field be tween the Otepää and Pandivere ice-mar ginal zones started to deglaciate at ap prox i mately 14,000–13,800 cal yr BP (Rosentau et al., 2007). AMS dates (12,380 ±70 and 12,350 ±60 ¹⁴C BP; 14,370 and 14,245 cal yr BP, re spec tively) of the ter res trial plant macroremains of the Lake Prossa silt show that the varved clays be low the silt had al ready been de - pos ited by 14,300 cal yr BP (Figs. 2 and 5). These val ues are in good agree ment with the age of the Otepää ice-mar ginal zone

(14,700–14,500 cal yr BP; Kalm, 2006), lo cated ca. 50 km south of Lake Prossa, and they roughly cor re spond with the age of the Sakala zone, which is cor re lated with the Valdemarpils zone in Lat via and the Older Dryas chronozone (Zelès and Markots, 2004).

The age of the Pandivere ice-mar ginal zone has been re - vised on the ba sis of the AMS ¹⁴C dates from the Haljala and Udriku sites (Figs. 2 and 5). These sites are lo cated close to the north ern limit of the Pandivere ice-mar ginal zone (Fig. 1A) and were tem po rarily flooded by the wa ters of the BIL (Saarse et al., 2009). The AMS ¹⁴C dates con firm that sed i men ta tion in these bas ins started no later than

Fig. 2. Loss-on-ig ni tion re sults from the Prossa (A), Udriku (B),

13,800 cal yr BP (Fig. 5; Saarse et al., 2009; Amon and Saarse, 2010), sup port ing the idea that the study ar eas were free of ice by that time. Our dates con form to varve counts in the Pärnu area, and they place the stag na tion of the Pandivere zone within ca. 13,900–13,800 cal yr BP (Hang et al., 2011).

These ages are 300–500 years older than those sug gested ear - lier (Vassiljev et al., 2005; Saarse et al., 2007; Rosentau et al., 2009) based on data from the Karelian Isth mus (Wohlfarth et al. 1999; Saarnisto and Saarinen, 2001), as AMS dates from the Es to nian sites were not avail able at that time. The ice re - ces sion could have oc curred even ear lier, as lac us trine sed i -

men ta tion in front of the re ced ing gla cier may have been de - layed by a few hun dred years (Warner et al., 1991).

The age of the Palivere ice-mar ginal zone has been revised sev eral times due to the ap pli ca tion of dif fer ent dat ing meth ods that did not pro duce re li able re sults (Raukas, 2009).

Serebryanny and Raukas (1966) cor re lated the Palivere ice re - advance with the Vimmerby ad vance in Swe den in con trast to Berglund (1979), who cor re lated the Palivere zone with the Levene Mo raines in Cen tral Swe den. The age of the Vimmerby ad vance was re cently re ap praised us ing the ter res trial cosmogenic nu clide method and was dated to ca.

Deglaciation chronology of the Pandivere and Palivere ice-marginal zones in Estonia 357

Haljala (C) and Tádva (D) deposits

14,000 ¹⁰Be yr (Johnsen et al., 2009; Johnsen, 2010). The ¹⁰Be tech nique has also been ap plied in stud ies of the Palivere ice-mar ginal zone of Es to nia. The age of 10 er ratic boul ders was found to range from 5200 to 15,200 years, with a mean of 13,600 ±1200 ¹⁰Be yr (Rinterknecht et al., 2006). Such de vi a - tion could re sult from the var i ously eroded sur faces of boul ders and/or be cause sev eral of the sam pled er rat ics lie at the con tem - po rary sea level and were cov ered with wa ters of dif fer ent stages of the Bal tic Sea be fore they were ex posed. The dat ing of glaciofluvial de pos its by the OSL method did not pro duce good re sults ei ther (Raukas and Stankowski, 2005). One rea son could be that the sed i ments were not ex posed prop erly to light dur ing their for ma tion or trans por ta tion (Johnsen, 2010). Fi - nally, Raukas (2009) ten ta tively sug gested that the Palivere ice-mar ginal belt was formed at ap prox i mately 11,500 ¹⁴C yr BP (13,300 cal yr BP) and that Es to nia be came free of ice cover in the sec ond half of the AllerÝd (Pirrus and Raukas, 1996).

Kalm (2011) and Kalm with co-au thors (Kalm et al., 2011) sug gested that the Palivere zone was formed later.

If the age of the Pandivere zone is 13,800 cal yr BP and the ice re treat from the Pandivere to the Palivere zone took place within 476 varve years (Hang and Sandgren, 1996), the Palivere ice-mar ginal zone and the re lated BIL A2 proglacial lake could have been formed ca. 13,300–13,200 cal yr BP. The

10Be age from the er ratic boul der at Kallaste (13 km west of Tallinn) showed a sim i lar age – 13,440 ±1300 (Rinterknecht et al., 2006). The bot tom most glaciolacustrine sed i ment from the

Fig. 3. Photo im ages of the sed i ment cores stud ied In the Prossa se quence varved clays form the basal part with 29 an nual varves. The Haljala se quence is en tirely lam i nated. In the Udriku se quence only the basal 18 cm is lam i nated. The Tádva se quence is clearly lam i nated be tween 450 and 470 cm.

Depth [cm] AMS ¹⁴C date Lab. no Cal i brated age Dated ma te rial Prossa

550–555 10,710 ±50 Poz-35466 12,825–12,735 Mac ros, un iden ti fied

575 10,410 +100 Poz-38459 12,580–12,105 Dryas leaves

595–600 11,650 ±50 Poz-35467 13,575–13,420 Mac ros, un iden ti fied 625–630 12,330 ±60 Poz-35468 14,405–14,090 Mac ros, un iden ti fied

645–650 12,380 ±70 Poz-36169 14,580–14,165 Dryas leaves

Udriku

673–675 10,190 ±50 Poz-31429 11,770–11,995 Leave frag ments

705–700 10,060 +60 Poz-30769 11,750–11,405 Dryas leaves

745–750 10,590 ±60 Poz-30429 12,770–12,410 Dryas leaves

768–773 11,240 ±100 Poz-36168 13,235–13,055 Dryas leaves

798–803 11,890 ±80 Poz-30430 13,835–13,665 Dryas leaves

813–818 12,090 ±80 Poz-36201 14,025–13,845 Dryas leaves

Haljala

210–215 10,970 ±150 Poz-22529 11,100–10,890 Macrofossils

310–315 11,780 ±60 Poz-22530 13,570–13,740 Macrofossils

410–415 11,750 ±80 Poz-22531 13,500–13,710 Macrofossils

Tádva

445–450 9920 ±100 Poz-39127 11,230–11,600 Dryas leaves

465–475 9830 ±190 Poz-39129 10,830–11,700 Leaves

515–518 11,310 ±130 Poz-39130 13,080–13,300 Dryas leaves

Cal i brated ages at one sigma

T a b l e 1 Ra dio car bon dates from the stud ied sites

Deglaciation chronology of the Pandivere and Palivere ice-marginal zones in Estonia 359

Fig. 5. Age-depth model from the Prossa (A), Udriku (B), Haljala (C) and Tádva (D) deposits Fig. 4. Grain-size dis tri bu tion of the Prossa (A), Udriku (B), Haljala (C) and Tádva (D) deposits

Tádva se quence yielded a min i mum age of 13,190 ±110 cal yr BP (Poz-39130) for deglaciation. This time span dif fers slightly from that we sug gested ear lier (Vassiljev et al., 2005).

The AMS date (Figs. 2 and 5) and the pol len as sem blages show that the sur round ing land scape of Tádva was al ready free of ice dur ing the AllerÝd chronozone. This ev i dence is in good ac - cord with the lat est re sults from Fin land, ac cord ing to which the ice mar gin reached the south ern coast of Fin land at ap prox i - mately 13,000 cal yr BP (Lunkka et al., 2004) and re mained at the Salpausselkä I Mo raine po si tion by ca. 12,500 cal yr BP (Svendsen et al., 2004) or 12,500 ±700 ¹⁰Be years (Rinterknecht et al., 2004). It is pos si ble that the Palivere ice-mar ginal zone was formed at the same time as the Levene mar ginal zone in Swe den (13,400 cal yr BP; Lundqvist and Wohlfarth, 2001), as sug gested by Berglund (1979) and Lundqvist (1992; cited af ter Lokrantz and Sohlenius, 2006).

CONCLUSIONS

1. Plant macrofossils, AMS ¹⁴C dates and lithostratigraphical pa ram e ters were used to study the ice re ces - sion chro nol ogy and age of proglacial lakes in Estonia.

2. AMS ¹⁴C dates from Lake Prossa, be tween the Otepää and Pandivere ice-mar ginal zones, in di cate that the study site was free of ice at ap prox i mately 14,300 cal yr BP, and they sup port the age pro posed for the Otepää zone (14,700–4500 cal yr BP).

3. The ice front had re treated to the north ern slope of the Pandivere Up land by 13,800 cal yr BP, as con firmed by the AMS ¹⁴C dates and cold-tol er ant pol len and plant re mains found in the glaciolacustrine sed i ments of the Udriku and Haljala sites.

4. Glaciolacustrine sed i ments of the Haljala and Udriku bas ins are de pos ited in proglacial lake A1, a north east ern bay of the BIL, con firm ing that proglacial lake A1 al ready ex isted at 13,800 cal yr BP.

5. The Palivere ice-mar ginal zone and proglacial lake A2 as - so ci ated with it were formed later, ca. 13,300–13,200 cal yr BP, which is in good ac cord with the lat est re sults from south ern Fin land and Swe den.

6. The new re sults show that ice re advanced dur ing the Palivere stade and ceased dur ing the AllerÝd chronozone. The age of this mar ginal zone has been ten ta tively cor re lated with that of the Levene zone in Swe den.

Ac knowl edge ments. We would like to ex press our grat i - tude to L. Amon for iden ti fy ing macrofossils and to the Elsevier lan guage ed it ing staff for lin guis tic help. We thank W. Wysota and two anon y mous re view ers for their valu able com ments and sug ges tions. The study was sup ported by the Es - to nian Min is try of Ed u ca tion and Re search (pro jects SF0332710s06), the Es to nian Re search Coun cil (SF0140021s12) and ESF (grant 8552).

REFERENCES

AMON L. and SAARSE L. (2010) – Postglacial palaeoenvironmental changes in the sur round ing Lake Udriku in North Es to nia. Geol.

Quart., 54 (1): 85–94.

AMON L., VESKI S., HEINSALU A. and SAARSE L. (2012) – Tim ing of late-gla cial veg e ta tion dy nam ics and re spec tive palaeoenvironmental con di tions in south ern Es to nia: ev i dence from Lake Nakri sed i ment re cord. J. Quatern. Sc., 27: 169–180.

BERGLUND B. E. (1979) – The deglaciation of south ern Swe den 13,500–10,000 B.P. Boreas, 8: 89–117.

BERGLUND B. E. and RALSKA-JASIEWICZOWA M. (1986) – Pol len anal y sis and pol len di a grams. In: Hand book of Ho lo cene Palaeo ec ol - ogy and Palaeohydrology (ed. B. E. Berglund): 455–484. John Wiley and Sons, Chichester.

GRIMM E. (2007) – Tilia Ver sion 1.0.1. Il li nois State Mu seum. Reserch and Col lec tion Cen ter. Spring field.

HANG T., OJALA A., KOHV M. and TUVIKENE T. (2011) – Varve chro - nol ogy and proglacial sed i men tary en vi ron ment in Pärnu area west ern Es to nia. In: Late Pleis to cene Glacigenic De pos its from the Cen tral Part of the Scan di na vian Ice Sheet to Youn ger Dryas End Mo raine Zone. Ex cur sion guide and Ab stract (eds. P. Johansson, J. P. Lunkka and P. Sarala): 94–94: Geol. Surv. Fin land, Rovaniemi.

HANG T. and SANDGREN P. (1996) – Magnetostratigraphy of varved clays. In: The Third Bal tic Strati graphic Con fer ence. Ab stracts. Field Guide (eds. T. Meidla, I. Puura, J. Nemliher, A. Raukas and L. Saarse):

152–154. Tartu.

HEIKKILÄ M., FONTANA S. L. and SEPPÄ H. (2009) – Rapid Lateglacial tree pop u la tion dy nam ics and eco sys tem changes in the east ern Bal tic re gion. J. Quatern. Sc., 24: 802–815.

HEINSALU A. and VESKI S. (2007) – The his tory of the Yoldia Sea in North ern Es to nia: palaeoenvironmental con di tions and cli ma tic os cil - la tions. Geol. Quart., 51 (3): 295–306.

JOHNSEN T. F. (2010) – Late Qua ter nary ice sheet his tory and dy nam ics in cen tral and south ern Scan di na via. Dis ser ta tions from the De part ment of Phys i cal Ge og ra phy and Qua ter nary Ge ol ogy, 22, Stock holm Uni - ver sity, 1–32, http://su.diva-por tal.org/smash/re cord.jsf?pid=diva - 2:311283

JOHNSEN T. F., ALEXANDERSON H., FABEL D. and FREEMAN S. P.

H. T. (2009) – New ¹⁰Be cosmogenic ages from the Vimmerby Mo - raine con firm the tim ing of Scan di na vian ice sheet deglaciation in south ern Swe den. Geogr. Ann., 91A: 113–120.

JONES G. A. and HENRY G. H. R. (2003) – Pri mary plant suc ces sion on re cently deglaciated ter rain in the Ca na dian High Arc tic. J. Biogeogr., 30: 277–296.

KALM V. (2006) – Pleis to cene chronostratigraphy in Es to nia, south east - ern sec tor of the Scan di na vian gla ci ation. Quatern. Sc. Rev., 25:

960–975.

KALM V. (2011) – Ice-flow pat tern and ex tent of the last Scan di na vian Ice Sheet south east of the Bal tic Sea. Quatern. Sc. Rev. (pub lished on line 24.02.2011; DOI:10.1016/j.quacirev.2010.01.019)

KALM V., RAUKAS A., RATTAS M. and LASBERG K. (2011) – Pleis to - cene Gla ci ation in Es to nia. In: Qua ter nary Glaciations – Ex tent and Chro nol ogy. A Closer Look (eds. J. Ehlers, P. L. Gibbard and P. D.

Hughes): 95–104. Elsevier, Am ster dam.

KIHNO K., SAARSE L. and AMON L. (2011) – Late Gla cial veg e ta tion, sed i men ta tion and ice re ces sion chronology in the sur round ings of Lake Prossa, cen tral Es to nia. Est. J. Earth Sc., 60: 147–158.

LOKRANTZ H. and SOHLENIUS G. (2006) – Ice mar ginal fluc tu a tions dur ing the Weichselian gla ci ation in Fennoscandia, a lit er a ture re view.

Tech ni cal Re port TR-06-36. Digitaltryck AB, Bromma, http://www.skb.se

LOUGAS L., UKKONEN P. and JUNGNER H. (2002) – Dat ing the ex - tinc tion of Eu ro pean mam moths: new ev i dence from Es to nia. Quatern.

Sc. Rev., 21: 1347–1354.

LOWE J. J., RASMUSSEN S. O., BJÖRCK S., HOEK W. Z., STEFFENSEN J. P., WALKER M. J. C., YU Z. C. and the INTIMATE group (2008) – Synchronisation of palaeoenvironmental events in the North At lan tic re gion dur ing the Last Ter mi na tion: a re vised pro to col rec om mended by the INTIMATE group. Quatern. Sc. Rev., 27: 6–17.

LUNDQVIST J. and WOHLFART B. (2001) – Tim ing and east-west cor re - la tion of south Swed ish ice mar ginal lines dur ing the Late Weichselian. Quatern. Sc. Rev., 20: 1127–1148.

LUNKKA J. P., JOHANSSON P., SAARNISTO M. and SALLASMAA O.

(2004) – Gla ci ation of Fin land. In: Qua ter nary Glaciations – Ex tent and Chro nol ogy. Part I: Eu rope (eds. J. Ehlers and P. L. Gibbard):

93–100. Elsevier, Am ster dam.

MANGERUD J., ANDERSEN S. T., BERGLUND B. E. and DONNER J.

J. (1974) – Qua ter nary stra tig ra phy of Norden, a pro posal for ter mi - nol ogy and clas si fi ca tion. Boreas, 3: 109–128.

PIRRUS R. (1969) – Strati graphic di vi sion of South Es to nian Late Gla cial de pos its by means of pol len anal y sis (in Rus sian with Eng lish sum - mary). Eesti NSV Teaduste Akadeemia Toimetised, Keemia, Geoloogia, 18: 181–190.

PIRRUS R. and RAUKAS A. (1996) – Late-Gla cial stra tig ra phy in Es to - nia. Pro ceed. Est. Acad. Sc., Geol., 45: 34–45.

PIRRUS R. and ROUK A.-M. (1979) – New data on the ge ol ogy of the Soitsj v Lake (in Es to nian with Eng lish sum mary). In: Eesti NSV saark gustike ja j ven ude kujunemine (ed. A. Raukas): 118–144. Valgus, Tallinn.

RAUKAS A. (2004) – Ap pli ca tion of OSL and ¹⁰Be tech niques to the es - tab lish ment of deglaciation chro nol ogy in Es to nia. Proc. Est. Acad.

Sc., Geol., 53: 267–287.

RAUKAS A. (2009) – When and how did the con ti nen tal ice re treat from Es to nia. Quatern. Internat., 207: 50–57.

RAUKAS A. and STANKOWSKI W. (2005) – In flu ence of sedimentological com po si tion on OSL dat ing of glaciofluvial de pos - its: ex am ples from Es to nia. Geol. Quart., 49 (4): 463–470.

RAUKAS A., RÄHNI E. and MIIDEL A. (1971) – Mar ginal gla cial for ma - tions in North Es to nia (in Rus sian with Eng lish sum mary). Valgus, Tallinn.

REIMER P. J., BAILLIE M. G. L., BARD E., BAYLISS A., BECK J. W., BERTRAND C., BLACKWELL P. G., BUCK C. E., BURR G., CUTLER K. B., DAMON P. E., EDWARDS R. L., FAIRBANKS R.

G., FRIEDRICH M., GUILDERSON T. P., HUGHEN K. A., KROMER B., McCORMAC F. G., MANNING S., BRONK RAMSEY C., REIMER R. W., REMMELE S., SOUTHON J. R., STUIVER M., TALAMO S., TAYLOR F. W., van der PLICHT J. and WEYHENMEYER C. E. (2004) – IntCal04 ter res trial ra dio car bon age cal i bra tion, 0–26 cal kyr BP. Ra dio car bon, 46: 1029–1058.

RINTERKNECHT V. R., CLARK P. U., RAISBECK G. M., YIOU F., BROOK E. J., TSCHUDI S. and LUNKKA J. P. (2004) – Cosmogenic

10Be dat ing of the Salpausselkä I Mo raine in south west ern Fin land.

Quatern. Sc. Rev., 23: 2283–2289.

RINTERKNECHT V. R., CLARK P. U., RAISBECK G. M., YIOU F., BITINAS A., BROOK E. J., MARKS L., ZELÈS V., LUNKKA J. P., PAVLOVSKAYA I. E., PIOTROWSKI J. A. and RAUKAS A. (2006) – The Last Deglaciation of the South east ern Sec tor of the Scan di na - vian Ice Sheet. Sci ence, 311: 1449–1452.

ROSENTAU A., HANG T. and KALM V. (2007) – Wa ter-level changes and palaeo ge ogra phy of proglacial lakes in east ern Es to nia: syn the sis of data from the Saadjärv Drum lin Field area. Est. J. Earth Sc., 56:

85–100.

ROSENTAU A., VASSILJEV J., HANG T., SAARSE L. and KALM V.

(2009) – De vel op ment of the Bal tic Ice Lake in the east ern Bal tic.

Quatern. Internat., 206: 16–23.

SAARNISTO M. and SAARINEN T. (2001) – Deglaciation chro nol ogy of the Scan di na vian Ice Sheet from the Lake Onega Ba sin to the Salpaussekä End Mo raines. Global Planet. Change, 31: 387–405.

SAARSE L. (1994) – Bot tom de pos its of small Es to nian lakes (in Rus sian with Eng lish sum mary). Eesti Teaduste Akadeemia, Tallinn.

SAARSE L. (2011) – Tim ing of deglaciation in North Es to nia. In: Late Pleis to cene Glacigenic De pos its from the Cen tral Part of the Scan di na - vian Ice Sheet to Youn ger Dryas End Mo raine Zone. Ex cur sion guide and Ab stract (eds. P. Johansson, J. P. Lunkka and P. Sarala): 129–130.

Geol. Surv. Fin land, Rovaniemi.

SAARSE L., VASSILJEV J., ROSENTAU A. and MIIDEL A. (2007) – Re - con struc tion of Late Gla cial shore dis place ment in Es to nia. Baltica, 20: 35–45.

SAARSE L., NIINEMETS E., AMON L., HEINSALU A., VESKI S. and SOHAR K. (2009) – De vel op ment of the late gla cial Bal tic ba sin and suc ces sion of the veg e ta tion cover as re vealed at Palaeolake Haljala, north ern Es to nia. Est. J. Earth Sc., 58: 317–333.

SEREBRYANNY L. R. and RAUKAS A. V. (1966) – Cor re la tion of Gothiglacial ice mar ginal belts in the Bal tic Sea de pres sion and the neigh bour ing coun tries (in Rus sian with Eng lish sum mary). Baltica, 3:

235–250.

SOHAR K. and MEIDLA T. (2009) – The Late Gla cial and Ho lo cene en vi - ron men tal his tory of shal low lakes in Es to nia, re vealed from subfossil ostracod data. Geol. Quart., 53 (2): 209–218.

STANÈIKAIT# M., KABAILIEN# M., OSTRAUSKAS T. and GUOBYT# R. (2002) – En vi ron ment and man around Lake Dãba and Pelesa, SE Lith u a nia, dur ing the Late Gla cial and Ho lo cene. Geol.

Quart., 46 (4): 391–409.

STANÈIKAIT# M., KISIELIEN# D. and STRIMAITIEN# A. (2004) – Veg e ta tion re sponse to the cli ma tic and hu man im pact changes dur ing the Late Gla cial and Ho lo cene: case study of the mar ginal area of Baltija Up land, NE Lith u a nia. Baltica, 17: 17–33.

STANÈIKAIT# M., ŠINK¤NAS P., ŠEIRIEN# D. and KISIELIEN# D.

(2008) – Pat terns and chro nol ogy of the Lateglacial en vi ron men tal de - vel op ment at Pamerkiai and Kašuèiai, Lith u a nia. Quatern. Sc. Rev., 27: 127–147.

STOCKMARR J. (1971) – Tab lets with spores used in ab so lute pol len anal y sis. Pol len et Spores, 13: 615–621.

STUIVER M., REIMER P. J. and REIMER R. (2005) – CALIB Ra dio car - bon Cal i bra tion (HTML Ver sion 5.0), http://ra dio car - bon.pa.qub.ac.uk/calib/

SVENDSEN J. I., ALEXANDERSON H., ASTAKHOV V. I., DEMIDOV I., DOWDESWELL J. A., FUNDER S., GATAULLIN V., HENRIKSEN M., HJORT C., HOUMARK-NIELSEN M., HUBBERTEN H. W., INGÓLFSON Ó., JAKOBSSON M., KJ€R K.

H., LARSEN E., LOKRANTZ H., LUNKKA J. P., LYSC A., MANGERUD J., MATIOUCHKOV A., MURRAY A., MÖLLER P., NIESSEN F., NIKOLSKAYA O., POLYAK L., SAARNISTO M., SIEGERT C., SIEGERT M. J., SPIELHAGEN R. F. and STEIN R.

(2004) – Late Qua ter nary ice sheet his tory of North ern Eur asia.

Quatern. Sc. Rev., 23: 1229–1271.

ZELÈS V. and MARKOTS A. (2004) – Deglaciation his tory of Lat via. In:

Qua ter nary Glaciations – Ex tent and Chro nol ogy. Part I: Eu rope (eds.

J. Ehlers and P. L. Gibbard): 225–243. Elsevier, Am ster dam.

VASSILJEV J., SAARSE L. and MIIDEL A. (2005) – Sim u la tion of the proglacial lake shore dis place ment in Es to nia. Geol. Quart., 49 (3):

253–262.

VEBER K. (1969) – Das Moor Saku (in Es to nian with Ger man sum mary).

Eesti Maaviljeluse ja Maaparanduse Teadusliku Uurimise instituudi Teaduslike tööde kogumik XVI: 248–274.

WARNER B. G., KUBIW H. J. and KARROW P. E. (1991) – Or i gin of postglacial ket tle-fill se quence near Georgetown, On tario. Can. J.

Earth Sc., 28: 1965–1974.

WOHLFARTH B., BENNIKE O., BRUNNBERG L., DEMIDOV I., POSSNERT G. and VYAHIREV S. (1999) – AMS ¹⁴C mea sure ments and macrofossil anal y ses of a varved se quence near Pudozh, east ern Karelia, NW Rus sia. Boreas, 29: 575–586.

Deglaciation chronology of the Pandivere and Palivere ice-marginal zones in Estonia 361