Geo log i cal Quar terly, 2011, 55 (3): 235–252
Geo mor phol ogy, sedimentology and or i gin of the glacigenic Z³ota Góra hills near Konin (Cen tral Po land)
Marek WIDERA
Widera M. (2011) – Geo mor phol ogy, sedimentology and or i gin of the glacigenic Z³ota Góra hills near Konin (Cen tral Po land). Geol.
Quart., 55 (3): 235–252. Warszawa.
The Z³ota Góra hills (Cen tral Po land) have been var i ously in ter preted as a kame, a sandur and as dif fer ent types of mo raine. Due to their mor phol ogy and in ter nal struc ture, the Z³ota Góra hills dif fer, how ever, from typ i cal depositional glacigenic land forms in the Eu ro pean low lands. Mor pho log i cally, the Z³ota Góra hills con sist of nu mer ous asym met ri cal and oval hills of var i ous sizes. The de pos its show a wide va ri ety of lithofacies, which are di ag nos tic for de bris flows, hyperconcentrated flows, sheetfloods, braided rivers, del tas and ephem eral lakes. The com bi na tion of such de pos its is char ac ter is tic of an en vi ron men tal set ting in clud ing both an end mo raine fan (de - bris flows, hyperconcentrated flows, sheetfloods and ephem eral lake de pos its) and a sandur (braided river, sheetfloods, and delta or ephem eral lake de pos its). There fore, these hills must be in ter preted as rep re sent ing an end mo raine/sandur mas sif. The hills were prob a - bly formed subaerially by melt wa ter in an interlobate area of the re treat ing Scan di na vian ice sheet.
Marek Widera, In sti tute of Ge ol ogy, Adam Mickiewicz Uni ver sity, Maków Polnych 16, PL-61-606 Poznañ, Po land, e-mail:
widera@amu.edu.pl (re ceived: June 01, 2010; ac cepted: May 30, 2011).
Key words: Cen tral Po land, sandur, end mo raine, interlobate landform.
INTRODUCTION
The max i mum ex tent of the ice sheet in Po land dur ing the Last Gla cial Max i mum (LGM) has been dis cussed since the 1920s, when Lencewicz (1927) dis tin guished the youn gest Scan di na vian glacigenic de pos its in Cen tral Po land. Since then, the max i mum ex tent has fre quently been re vised (Rotnicki, 1963; Kozarski, 1981, 1986, 1990; Stankowska and Stankowski, 1988; Rotnicki and Borówka, 1990;
Karczewski, 1994; Stankowski et al., 1995; Morawski, 1999, 2009; Wysota, 1999; Krzywicki, 2002; Petera and Forysiak, 2003; Przybylski, 2008). Marks (2002, 2005) and Marks et al.
(2006) have re viewed the pre vi ous opin ions and the most re - cent con cepts con cern ing the max i mum ex tent of the ice in Po land dur ing the LGM.
In the vi cin ity of Konin (Cen tral Po land), how ever, the LGM max i mum ice ex tent is still un der dis cus sion. Some re - search ers have ar gued that the Z³ota Góra hills are of Weichselian (Vistulian) age (e.g., Berendt and Keilhack, 1894;
£yczewska, 1960; Krygowski, 1974; Gogo³ek and Mañkowska, 1989; Sza³amacha and Skompski, 1999; Marks, 2005; Marks et al., 2006). Other au thors date the Z³ota Góra
hills as Wartanian (Late Saalian; e.g., Lencewicz, 1927;
Miko³ajski, 1927; Woldstedt, 1931; Majdanowski, 1950;
Rotnicki, 1963; Stankowska and Stankowski, 1988;
Stankowski et al., 1995; Widera, 1993, 2000; Petera and Forysiak, 2003). Petera and Forysiak (2003) have re viewed in de tail the evo lu tion of ideas on the of LGM ice ex tent in the study area.
The hy poth e ses con cern ing the Z³ota Góra gen e sis can be di vided into three groups. First, based on geomorphological cri te ria only, the hills have been re garded as an end mo raine and ground mo raine of var i ous ages (cf. Petera and Forysiak, 2003). Sec ondly, the Z³ota Góra hills have been iden ti fied as a kame of Wartanian age on the ba sis of geomorphological cri te - ria in com bi na tion with sedimentological data (K³ysz, 1981, 1985). Thirdly, tak ing the in ter nal struc ture and geomorpho - logical fea tures as the most im por tant cri te ria, the pres ent au - thor has in ter preted it as an “interlobate sandur fan” dat ing from the Wartanian Gla ci ation (Widera, 1993).
The main ob jec tive of the pres ent con tri bu tion is to de fine the glacigenic land forms and to dis cuss the or i gin of the Z³ota Góra hills. This work is a con tin u a tion of ear lier stud ies by the pres ent au thor (Widera, 1993).
STUDY AREA
The study area (52°010’ N, 18°018’ E) is lo cated in the vi - cin ity of Konin, Cen tral Po land (Fig. 1). The area un der in ves ti - ga tion is 324 km2, but the area of the Z³ota Góra hills only is less than 63 km2 (approx. 9 km long and 7 km wide). The al ti - tude ranges be tween 79.9 and 191.0 m a.s.l. The low est point lies in the Warta Val ley west of Konin, whereas the high est one is the top of the Z³ota Góra (Fig. 2).
Ac cord ing to the lat est opin ions, this area be longs to the glaciomarginal zone of the Weichselian Gla ci ation. The LGM is rep re sented here by the Leszno and Poznañ phases, which cor re spond to the Brandenburg and Frank furt phases in Ger - many, re spec tively (Woldstedt, 1931). Their end mo raines are quite close to gether and even over lap 30 km NE of Konin (Fig. 1B). There fore, on the 1:500 000 geo log i cal map of Po - land (Marks et al., 2006), the Z³ota Góra hills rep re sent the end mo raine of the Leszno Phase (Fig. 1C).
The field work for the pres ent study was car ried out in three sand pits, i.e. Go³¹bek I, Go³¹bek II and Go³¹bek III, lo cated 5–7 km ESE of Konin, in the north ern part of the study area (Fig. 2).
METHODS
The land forms were mapped for the pres ent study from 1:25 000 and 1:50 000 top o graphic maps, yield ing the mor pho - log i cal sketch of Fig ure 2. Six W–E and four N–S mor pho log i - cal cross-sec tions are shown in Fig ure 3.
Twelve sedimentological pro files were ana lysed in the three sand pits for their tex ture, struc ture, de for ma tions and palaeocurrent di rec tions. The sed i ment ar chi tec ture was re - corded us ing a com bi na tion of dig i tal pho to graphs, sketches and sed i men tary logs. The palaeocurrent data were col lected from pla nar and trough cross-strat i fied lay ers only.
For the sed i ment tex ture and struc ture, a lithofacies code, based on Miall (1977, 1985) and Eyles et al. (1983), was used (Ta ble 1). The orig i nal codes es tab lished by Miall (1977, 1985) for flu vial de pos its only, with ad di tions made by Eyles et al.
(1983) for diamicts, was slightly mod i fied. The struc tural code no ta tion “d”, i.e. de formed, is used for all in ves ti gated de pos its (Ta ble 1). For ex am ple, lithofacies GDmd and Thd in di cate a mas sive and de formed grav elly diamicton, and a hor i zon tally strat i fied and de formed silt, re spec tively.
RESULTS
MORPHOLOGY
The hills of Z³ota Góra, cul mi nat ing 191 m a.s.l., are bor - dered by hummocky ground mo raine at ~110–160 m a.s.l. to the south. To the west and east, the hills are flanked by shal low de pres sions of the Powa and Topiec rivers, re spec tively, which both drain to the north. These val leys change in al ti tude from more than 100 m to less than 90 m a.s.l. In con trast, the north ern land scape is 2–5 km wide and rel a tively flat. It is the Warta Val ley, which is a well-de fined rem nant of the Warszawa–Berlin ice-mar ginal streamway, reach ing an al ti - tude of ~80–85 m a.s.l. (Figs. 2 and 3).
Based on mor pho log i cal cri te ria, the Z³ota Góra hills can be di vided into the fol low ing three seg ments.
Fig. 1. Lo ca tion map
A – max i mum ex tent of the Weichselian ice sheet in Po land and neigh bour - ing ar eas, mod i fied af ter sev eral au thors; B – ma jor phases of the Late Weichselian Gla ci ation in Cen tral Po land, com piled from Kozarski (1981) with mod i fi ca tion af ter Marks (2005) and Marks et al. (2006); C – part of the 1:500 000 geo log i cal map of Po land at Konin, af ter Marks et al. (2006).
Most rel e vant sym bols: 14 – outwash sand and gravel; 17 – ter mi nal-mo - raine sand, gravel, boul der and till; 18 – meltout or lodge ment till, weath - ered till, sand and gravel
Code Granulometry
D diamicton
G gravel
S sand
T silt
C or ganic de posit
Code Sed i men tary struc ture
m mas sive
p pla nar cross-strat i fi ca tion t trough cross-strat i fi ca tion r rip ple cross-lam i na tion h hor i zon tal lam i na tion
d de formed
T a b l e 1 Codes of the tex tural and struc tural
el e ments of the var i ous lithofacies (mod i fied af ter Miall, 1977, 1985;
Eyles et al., 1983)
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 237
Fig. 2. Sim pli fied mor phol ogy of the Z³ota Góra Mas sif and sur round ing area, with lo ca tion of the sand pits un der study and cross-sec tions (A–H, I–XII)
Al ti tudes are be tween 79.9 and 191.0 m a.s.l.; con tour in ter vals 10 m (90–190 m a.s.l.)
Fig. 3. Mor pho log i cal cross-sec tions trough the Z³ota Góra Mas sif A – W–E cross-sec tions; B – N–S cross-sec tions; for lo ca tion see Fig ure 2
1. The south ern seg ment, which is 7 km long and 2 km wide, has an W–E ori en ta tion. This seg ment con sists of nu mer - ous small mounds (Fig. 2) that oc cur spo rad i cally more than 10 m above the sur round ing area, which has an al ti tude of
~140–150 m a.s.l. The south ern flank of this seg ment is steep (Figs. 2 and 3).
2. The high est point of the study area, i.e. the Z³ota Góra, forms part of the cen tral seg ment (Fig. 2). The ax ial part of this seg ment, reach ing an al ti tude of over 140 m a.s.l., is, like the south ern seg ment, 7 km long and 2 km wide. Three flanks (the south ern flank is dif fer ent), are rel a tively steep and deeply eroded be tween 130 and 150 m a.s.l. (Fig. 3).
3. The most im por tant area for the pres ent study is the north ern seg ment of the Z³ota Góra hills, which lies close to the Warszawa–Berlin streamway in the north. There are at least five hills, but the con stit u ent de pos its are ex posed in two of them only. Their mor phol ogy is sim i lar to the above-men tioned cen tral seg ment. The rel a tive height of the hill with the Go³¹bek I sand pit is ~30–45 m and the hill with the Go³¹bek II and Go³¹bek III sand pits is ~10–25 m high (Figs. 2 and 3).
SEDIMENTOLOGY
GO£¥BEK I
The Go³¹bek I sand pit is 200 m long, 150 m wide and lo - cated at 124–138 m a.s.l. (Fig. 4). Four sedimentological pro - files have been se lected for de tailed ex am i na tion. They con tain ten lithofacies, which are grouped into four as so ci a tions (Figs. 5–7).
D e s c r i p t i o n. – Four lithofacies as so ci a tions have been dis tin guished, with the fol low ing char ac ter is tics.
Lithofacies as so ci a tion 1 (SGt, SGp, St, Sp, Sh, Sr) is com - posed of grav elly sand, sandy gravel and sand with var i ous types of strat i fi ca tion: trough, pla nar, hor i zon tal and rip ple.
These lithofacies are more com mon in the lower part of the ex - po sure (Figs. 5 and 6). The in di vid ual lay ers are be tween 3 cm and 1.5 m thick and their bases are pre dom i nantly ero sional.
All these lithofacies are char ac ter ized by a ma trix-sup ported tex ture and, usu ally, nor mal grad ing. More over, the cross-strat - i fied units gen er ally dip to wards the south (Fig. 5B, D).
Lithofacies as so ci a tion 2 con sists of hor i zon tally strat i fied or mas sive and de formed silts (Th, Tmd) to gether with hor i - zon tally strat i fied sand (Sh). These lithofacies are len tic u lar in shape, 20–30 m long and up to 1–2 m thick (Figs. 6A and 7A).
In one case, lithofacies Th and Sh, i.e. silt and sand, are strat i - fied hor i zon tally and un dis turbed (Fig. 7B). In an other case (lithofacies Tmd), ini tially mas sive silt is now de formed (Fig. 6B, C).
Lithofacies as so ci a tion 3 is com posed of mas sive and de - formed grav elly diamicton (DGmd), mas sive and de formed diamicton (Dmd) as well as mas sive and de formed diamictic gravel (DGmd). This as so ci a tion is com mon in the up per parts of the west ern and north ern pro files in the Go³¹bek I sand pit.
These lithofacies are de formed and their basal con tacts are al - ways sharp (Figs. 6A, C and 7A, D). The to tal thick ness of the mas sive and de formed grav elly diamicton (DGmd), and of the mas sive and de formed diamictic gravel (GDmd) reaches 4–6 m (Fig. 7A). These lithofacies con sist of a mix ture of ma trix-sup - ported grav els and boul ders, which can ex ceed 0.5 m in di am e - ter (Fig. 7D). How ever, in the case of mas sive and de formed diamicton (Dmd), the thick ness de creases from 4–6 m to less than 1 m to wards the south (Fig. 6A). Lithofacies Dmd is pre - dom i nantly fine-grained (i.e. clay, silt, sand) with sporsdic iso - lated peb bles. The fold axes of the de formed diamictons are roughly ori en tated E–W.
Lithofacies as so ci a tion 4 con sist ing of grav elly sand with pla nar strat i fi ca tion (SGp), only seen at the top of the ex po sure (Figs. 6A, D and 7A), con tains a ma trix with a rel a tively high amount of clay and silt (Fig. 6D). One or two sets of strata dip - ping to the south can be dis tin guished. Their com bined thick - ness ranges be tween 2 and 3 m and their lower bases are al ways sharp (Figs. 6A and 7A).
I n t e r p r e t a t i o n. – The four lithofacies as so ci a tions are ge net i cally in ter preted as fol lows.
Lithofacies as so ci a tion 1 is char ac ter is tic of a braided-river en vi ron ment (Maizels, 1993; Krüger, 1997; Krzyszkowski and Zieliñski, 2002; Zieliñski and van Loon, 2003; Kj³r et al., 2004). The lithofacies SGt, St, SGp, Sp and Sr rep re sent bedforms mi grat ing in braided chan nels (Allen, 1965; Miall, 1977, 1985). They are typ i cal of 2-D and 3-D dunes (megaripples) and rip ples. Ac cord ing to Maizels (1993), sandurs are pro to types of land forms built up by braided-river lithofacies as sem blages. Lithofacies Sh shows that melt wa ter ran over the en tire depositional area. The hor i zon tal strat i fi ca - tion of the sands was pro duced un der con di tions of lower flow re gime. This unit has a rel a tively flat top, which is in ter preted as the topset and steeply slop ing foreset of a delta (Fig. 5C, D).
This lithofacies as sem blage thus re cords a glaciofluvial delta en ter ing a sandur, which was cov ered at the time by de pos its of a braided river (cf. Smith and Ashley, 1985).
The sec ond, fine-grained, lithofacies as sem blage is com posed of fa cies Th, Tmd and Sh. This as so ci a tion is in ter preted as formed in ephem eral lakes. The sed i ments were mainly de pos ited from sus pen sion in al most stag nant wa ter or un der con di tions of very low-en ergy wa ter cur rents. The silty and sandy beds form rhythms re flect ing changes in ab la tion (Mokhtari Fard and Gruszka, 2007).
They can be at trib uted to long-lived sea sonal (rather than daily) fluc tu a tions in wa ter sup ply. The sed i ments are usu ally dis turbed in their top parts, most prob a bly dur ing rapid de po si tion of the over ly ing flow tills (cf. van Loon, 2009). Sim i lar de pos its have been de scribed by Gruszka and Zieliñski (1996) and Gruszka (2001, 2007) and as glaciolacustrine de pos its in the Be³chatów lig - nite mine in Cen tral Po land.
Fig. 4. Out line of the Go³¹bek I sand pit with lo ca tion of the sed i men tary pro files shown in Fig ures 5–7
As so ci a tion 3 is built of diamictic lithofacies, which are ei - ther un der lain by sand and gravel de pos its or oc cur on top of the sed i men tary suc ces sion. More over, all of them are de - formed with clearly vis i ble folds, in di cat ing fluidization dur ing de po si tion by co he sive mass flows, i.e. de bris flows (Nemec and Steel, 1984; Pisarska-Jamro¿y, 2006). These fea tures are char ac ter is tic of flow tills de rived from the ice sheet (Krüger and Marcussen, 1976; Ruszczyñska-Szenajch, 1982; Eyles et al., 1983; Brodzikowski and van Loon, 1987; Krüger, 1994;
Zieliñski and van Loon, 1996; Krüger, 1997; Huddart et al., 1999; Krüger et al., 2010). The oc cur rence of flow tills com - posed of lithofacies DGmd, Dmd and GDmd is ev i dence of de - po si tion rel a tively close to the ice sheet mar gin (Krüger and Marcussen, 1976; Kasprzak and Kozarski, 1984, 1989; Paul and Eyles, 1990; Ev ans et al., 1999; Zieliñski and van Loon, 2000; Ev ans and Twigg, 2002; Krzyszkowski and Zieliñski, 2002). This ex plains why this lithofacies as so ci a tion is ex posed less than 50–70 m from the north ern wall of the Go³¹bek I sand pit. The gen eral ice-flow di rec tion was from north to south.
This is sup ported by the po si tion of the flow tills and their ar -
chi tec ture, as well as by the fold axes that have an E–W di rec - tion. The fourth thick, lithofacies as so ci a tion, con sist ing of only one lithofacies (large-scale pla nar strat i fied grav elly sand, SGp) oc curs at the top of the exposure. The sands con tain a sig - nif i cant amount of clay and silt, which in di cates that this suc - ces sion is fairly sim i lar to the “dirty grav els”, but finer.
Zieliñski and van Loon (2000) have in ter preted such poorly sorted, ma trix-sup ported grav elly sands as typ i cal of the prox i - mal zone of end mo raine fans. They are tran si tional be tween gravel and sand/silt sheetfloods, and show a de creas ing grain size to wards the south. The sed i ments were prob a bly de pos ited un der high-en ergy con di tions, where the fan sur face was rel a - tively steep and trans port was not channelized (cf. Zieliñski and van Loon, 2000).
GO£¥BEK II
The Go³¹bek II sand pit is more than 500 m long and 350 m wide. It is at 105–115 m a.s.l. (Fig. 8). Six sedimentological
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 239
Fig. 5. Sec tion in the cen tral part of the Go³¹bek I sand pit A and C – pho to graphs of the sec tion; B and D – cor re spond ing sed i men tary logs;
for lo ca tion see Fig ure 4; for ex pla na tion of the lithofacies codes see Ta bles 1 and 2
pro files have been stud ied. They in clude twenty lithofacies, which have been grouped into seven as so ci a tions (Figs. 9–13).
D e s c r i p t i o n. – The seven lithofacies as so ci a tions in this pit have the fol low ing char ac ter is tics.
Lithofacies as so ci a tion 1 con sists of mas sive diamicton (Dm), which may be de formed (Dmd). These de pos its are the high est ones in the pro files lo cated in the north ern most parts of the Go³¹bek II sand pit (Figs. 9 and 10). Their thick ness is up to 3.5 m, their hor i zon tal ex tent reaches 15 m, and the base is sharp. More over, the in te rior struc ture of these lithofacies is lo - cally folded (Fig. 9A, C).
Lithofacies as so ci a tion 2 con sists of mas sive de pos its, viz.
gravel (Gm), sandy gravel (GSm), diamictic gravel (GDm) and sand (Sm). All lithosomes are len tic u lar in shape and their thick nesses range from 0.3 to 2.5 m (Figs. 9, 10 and 13). Their basal con tact is al ways ero sional. Apart from lithofacies Sm,
this as so ci a tion con sists of ma trix-sup ported to clast-sup ported well-rounded grav els (so-called “egg grav els”) with finer ad - mix tures. These grav els con tain gneiss es, gran ites, marls and diamictons (Fig. 10).
Both the large-scale pla nar strat i fied (Sp) and the de formed equiv a lents (Spd) of lithofacies as so ci a tion 3 are more than 0.3 m thick, reach ing up to 3 m (Figs. 9, 12 and 13). The strata over lain by diamictons are usu ally faulted with a throw of less than 10 cm (Fig. 9A, B, D).
The fourth as so ci a tion con sists of only one lithofacies: pla - nar-strat i fied gravel (Gp), which is char ac ter ized by two pseudo-imbricated sets of strata. Both sets dip to the SSW (Fig. 11). The length of these sets is more than 15 m and their thick nesses range from 1 to 2 m (Fig. 11A). The base of the sets is slightly ero sional, so that the con tact be tween both sets is sharp. The lower set con sists mainly of gran ules and fine peb -
Fig. 6. Sec tion in the west ern part of the Go³¹bek I sand pit
A – gen eral ar chi tec ture; B–D – lithofacies de scribed in de tail in the text and in Ta ble 2; photo D shows the so-called “dirty grav els”;
for lo ca tion see Fig ure 4; for ex pla na tion of the lithofacies codes see Ta bles 1 and 2; other ex pla na tions as in Fig ure 5
bles. It is clast-sup ported with a ma trix of coarse sand and fine gravel. In con trast, the up per set con sists of me dium-sized and coarse peb bles, and it is clast-sup ported with a ma trix of fine gravel (Fig. 11B).
Lithofacies as so ci a tion 5 is com posed of pla nar-strat i fied gravely sand and sand (SGp, Sp) with, in gen eral, ad mix tures of gravel. This as so ci a tion is ex posed at the top of the pro file in the east ern part of the Go³¹bek II sand pit (Fig. 8). Its lat eral ex - tent is more than 20 m and its thick ness ranges from 1 to 3 m (Figs. 10 and 12). The sands be long to the me dium and coarse sand frac tions. The gravel clasts are up to 20–40 cm across and they oc cur close to the base of this suc ces sion (Fig. 12A, B, E), which dips to wards the SE (Fig. 10A) or to the SW (Fig. 12B).
Lithofacies as so ci a tion 6 (St, Sp, Sh, SGt, SGh) con sists of trough, pla nar and hor i zon tally strat i fied sand and grav elly sand. The sets of this as so ci a tion, which range in thick ness from 0.6 m (Fig. 12C) to more than 6 m (Fig. 13C, D), con tain crude (>5 cm) strat i fi ca tion (Figs. 10A, 12C, D and 13C, D), whereas the in di vid ual strata are 0.2–1 m thick. The sets con sist of sands with sporadical ad mix tures of gravel. All lithofacies of this as so ci a tion are char ac ter ized by nor mal grad ing. The cross-strat i fied units gen er ally dip to wards the SE–SW (Figs. 10A, 12B and 13D).
Lithofacies as so ci a tion 7 con sists of hor i zon tally strat i fied silt and sand (Th, Sh) as well as hor i zon tally strat i fied and de - formed silt and sand (Thd, Shd). These de pos its are lim ited lat - er ally to ~20–30 m and ver ti cally to 5–7 m. Most com mon are sets of hor i zon tally strat i fied silts (Th) and hor i zon tally strat i - fied sands (Sh). Co-sets of these two lithofacies, i.e. hor i zon -
tally strat i fied sands with in ter ca la tions of hor i zon tally strat i - fied silts (Sh, Th) are also char ac ter is tic (Fig. 13A, B). The suc - ces sion con tains mas sive gravel (Gm) and pla nar strat i fied sands (Sp) that are less then 10 m long and 1 m thick. Mas sive grav els de form the un der ly ing de pos its (Fig. 13A, B). The large-scale pla nar cross-strat i fied sands dip to wards the WSW (Fig. 13B).
I n t e r p r e t a t i o n. – The seven lithofacies as so ci a - tions of this sand pit are in ter preted as fol lows.
The diamictic lithofacies as so ci a tion 1 is sim i lar to that in the Go³¹bek I sand pit. Con se quently, it is in ter preted as con - sisting of de bris flow de pos its, i.e. flow tills, which were de pos - ited along the fron tal ice slope, and their flow di rec tion was from north to south.
Lithofacies as so ci a tion 2, which is char ac ter ized by mas - sive struc ture, i.e. Gm, GSm, GDm, SGm and Sm, rep re sents grain flows to hyperconcentrated flows. Rel a tively well-sorted de pos its are com monly in ter preted as the re sult of de po si tion by grain flows (Nemec and Steel, 1984; Costa, 1988; Huddart et al., 1999). On the other hand, poorly sorted lithofacies with - out dis tinct grad ing, such as the diamictic grav els (GDm) of this as so ci a tion, are typ i cal of “dirty grav els” (Mokhtari Fard and Gruszka, 2007). Such de pos its re sult from hyperconcentrated flows (Nemec and Steel, 1984; Costa, 1988;
Pisarska-Jamro¿y, 2007). The so-called “egg grav els” pose an in ter pre ta tional prob lem. These grav els are com posed of gneiss, gran ite, marl and diamicton clasts, in this case well-rounded (see Fig. 10). The or i gin of the “egg grav els” has been clar i fied by Glas ser et al. (1999), who sug gested that these
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 241
Fig. 7. Sec tion in the north ern part of the Go³¹bek I sand pit
A – gen eral ar chi tec ture; B–D – lithofacies de - scribed in de tail in the text and in Ta ble 2;
for lo ca tion see Fig ure 4; for ex pla na tion of the lithofacies codes see Ta bles 1 and 2;
other ex pla na tions as in Fig ures 5 and 6
Lithofacies code Ggen eral de scrip tion Char ac ter is tics
Dm, Dmd mas sive or mas sive
and de formed diamicton
ma trix-sup ported diamicton with iso lated grav els, 0.1– >5 m thick, sharp basal con tact, usu ally folded, some times in ter ca lated by other diamictic lithofacies,
pro duced by mass flows
DGmd, GDmd, GDm mas sive and de formed gravely
diamicton or diamictic gravel ma trix-sup ported to clast-sup ported diamictic de pos its, up to 1 m thick lens with clasts of 0.1–0.5 m, de formed with diamictons, formed by mass flows
GSm mas sive sandy gravel
clast-sup ported gravel with sandy ma trix, 2–3 m thick units, sharp basal con tact, char ac ter is ti cally well-rounded clasts, i.e. “egg grav els”, up to 0.4 m in size,
vary ing in li thol ogy and age, as so ci ated with lithofacies GDm and GSm, de rived from orig i nally hyperconcentrated sub- and en gla cial wa ter masses,
fi nally re sult ing in mass flows
Gp pla nar cross-strat i fied gravel
peb ble and cob ble gravel with gran ules and a coarse sand ma trix, clast-sup ported, 0.7–1.1 m thick units, nor mally graded, sharp basal con tact,
pseudo-imbricated, de pos ited from high-en ergy cur rents with mi grat ing 2-D dunes in deep braided channels
SGm, SGmd mas sive or mas sive
and de formed grav elly sand
coarse to me dium sand and fine gravel, 0.2–0.7 m thick ir reg u lar beds, sharp basal con tact, in ter preted as mass-flow de pos its
SGh hor i zon tally strat i fied
grav elly sand coarse to me dium sand and fine gravel, i.e. gran ules and peb bles, more than 1 m thick and 100 m long units, de pos ited from sheetfloods
SGp, SGt pla nar or trough cross-strat i fied grav elly sand
sand with ad mix tures of gran ules and peb bles, ma trix-sup ported, 0.25–0.6 m thick beds formed by mi gra tion of 2-D and 3-D bedforms. Typ i cally 1– >3 m thick units, pla nar cross-strat i fied, of ten nor mally graded, de pos ited in prox i mal part of fan
Sm, SCm mas sive sand or mas sive sand
with or ganic ma te rial me dium to fine sand with ox i dized Fe in clay frac tion, some times with or ganic con tent (SCm), 0.05–0.6 m thick units, mod i fied by soil pro cesses
Sh hor i zon tally strat i fied sand
fine sand, 0.1–0.2 m thick beds with not-ero sional but sharp con tact, rep re sent ing glaciolacustrine de po si tion in stand ing wa ter. Me dium to fine sand,
typ i cally 0.5–1.5 m thick and more than 50–100 m long units, base and top ly ing par al lel to each other, de pos ited from sheetfloods in the lower flow re gime.
Coarse to me dium sand and fine gravel, i.e. gran ules and peb bles, de pos ited from sheetfloods
St trough cross-strat i fied sand
coarse to fine sand, 0.06–0.45 m thick units, nor mally graded, ev i dently ero sional top and basal con tacts, typ i cal for trough in fill ing
of me dium and thick (>5 cm) bedforms, formed by mi grat ing 2-D and 3-D dunes in braided channels
Sr rip ple cross-strat i fied sand me dium to fine sand, in di vid ual units less than 0.06 m thick, sharp basal con tact, typ i cal for trough in fill ing of thin (<5 cm) bedforms, rip ples
Sp, Spd pla nar or pla nar and de formed cross-strat i fied sand
coarse to fine sand, 0.2–3 m thick lay ers, char ac ter is tic of pos i tive me dium and large 2-D bedforms, i.e. dunes, de formed close to the mass flow de pos its; 0.5–3 m thick
units typ i cal for sheetfloods on delta and fan surface
Tm, Tmd mas sive or mas sive
and de formed silt
sandy silt to clayey silt, 0.1–0.8 m thick and up to 50 m long beds, de pos ited in stand ing wa ter in ephem eral lakes, some times de formed
by over ly ing mass flow de pos its
Th hor i zon tally strat i fied silt sandy silt to clayey silt with sandy in ter ca la tions, 0.1–0.4 m thick lay ers and 40–50 m long units, de pos ited in ephem eral lakes
Tp pla nar cross-strat i fied silt silt and sandy silt in ter ca lat ing with thick pla nar cross-strat i fied sand, in di vid ual strata 0.001–0.05 m thick and more than 150–200 m long, typ i cal for a glaciofluvial fan
T a b l e 2 Char ac ter is tics of the lithofacies un der study
grav els re sult from ro ta tion and abra sion of large cob bles and peb bles by pass ing wa ter within a de bris-rich cre vasse in the ice body. How ever, this in ter pre ta tion does not ex plain the co-oc cur rence of very hard and very soft grav els. The pres ent au thor there fore sug gests that “egg grav els” came rather into ex is tence in gla cial tun nels or full-pipe chan nels in su pra-, en-, or subglacial en vi ron ments. Both the soft-rock clasts and the gneiss and gran ite clasts rep re sent, in the pres ent au thor’s view, ma te rial eroded from the sub stra tum by the gla cier.
The large-scale pla nar cross-strat i fied sand de pos its (Sp, Spd) of as so ci a tion 3 are char ac ter is tic of an al lu vial fan. They are in ter preted as sheetflood de pos its, where the wa ter was thus not re stricted to chan nels on the fan (cf. Zieliñski and van Loon, 2000, 2003; Krzyszkowski and Zieliñski, 2002; Shukla, 2009).
This lithofacies orig i nated un der en ergy con di tions rang ing from high en ergy (SGp, more prox i mal fan) to low en ergy (Sp and Tp, more dis tal fan; cf. Zieliñski and van Loon, 2000). These de pos - its show fre quent nor mal faults. The dis place ment of these faults reaches 10 cm, their strike shows var i ous ori en ta tions, and the max i mum prin ci pal stress must have been al most ver ti cal. The fault ar chi tec ture thus prob a bly re flects dewatering of the glaciofluvial fan de pos its. It is ev i dence for syn- and/or postsedimentary de for ma tions caused by the melt ing of ice or small pieces of bur ied ice. A sim i lar but sig nif i cantly larger synsedimentary fault with a throw reach ing ~1 m has been de - scribed from the Go³¹bek II sand pit (Widera, 1993).
The large-scale pla nar cross-strat i fied grav els (Gp) of lithofacies as so ci a tion 4 are well-ex posed and a pseudo-imbricated po si tion of par ti cles is per fectly vis i ble.
This lithofacies is typ i cal of lon gi tu di nal bars in braided rivers with gravel-sized bedload (Allen, 1965; Miall, 1977). The axes of these bars are par al lel to the pre vail ing trans port di rec tion and the peb bles ac cu mu late on the down-cur rent sides of the lon gi tu di nal bars. These bars are usu ally formed dur ing in -
creas ing dis charge (Allen, 1970; Kleinhans, 2001). In clined po si tions of gravel clasts are com mon in sev eral proglacial en - vi ron ments (e.g., Knudsen and Marren, 2002; Pisarska- Jamro¿y, 2006). Thick (>5 cm) pla nar cross-strat i fied grav els are ev i dence of sed i men ta tion by channelized cur rents un der
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 243
Fig. 8. Out line of the Go³¹bek II sand pit with lo ca tion of the sed i men tary pro files shown in Fig ures 9–13
Fig. 9. Sec tion in the north east ern part of the Go³¹bek II sand pit
A – gen eral ar chi tec ture; B–D – lithofacies de scribed in de tail in the text and in Ta ble 2; for lo ca tion see Fig ure 8;
for ex pla na tion of the lithofacies codes see Ta bles 1 and 2; other ex pla na tions as in Fig ures 5 and 6
Fig. 10. Mass-flow de pos its in the east ern part of the Go³¹bek II sand pit
A – gen eral po si tion of mass-flow de pos its, con sist ing of clast-sup ported grav els in the pro file; B – ex am ple of grav els in clud ing an oma lously well-rounded, the so-called “egg grav els”, Cre ta ceous marls and Pleis to - cene diamictons; for lo ca tion see Fig ure 8
Fig. 11. Grav elly dune (megaripple) in the east ern part of the Go³¹bek II sand pit
A – gen eral view of dune de pos its, clast-sup ported grav els;
B – two sets of pseudo-imbricated grav els dip ping in the same di rec tion;
for lo ca tion see Fig ure 8
Fig. 12. Sec tion in the east ern part of the Go³¹bek II sand pit
A – gen eral view; B – gen eral ar chi tec ture; C–E – lithofacies de scribed in de tail in the text and in Ta ble 2; for lo ca tion see Fig ure 8; for ex pla na tion of the lithofacies codes see Ta bles 1 and 2; other ex pla na tions as in Fig ure 5
very high-en ergy con di tions and they can be re garded as char - ac ter is tic of the most prox i mal parts of sandur fans (Brodzikowski and van Loon, 1987; Maizels, 1993; Zieliñski and van Loon, 2003).
In lithofacies as so ci a tion 5, the lithofacies SGp and Sp, with thick nesses reach ing up to 3 m, can be in ter preted, as for lithofacies as so ci a tion 4 from the Go³¹bek I sand pit, as re sult -
ing from sheetfloods in the prox i mal zone of a glaciofluvial fan (cf. Zieliñski and van Loon, 2000). By con trast, the de pos its from the Go³¹bek II sand pit are both more sandy and better sorted and strat i fied. Thus, they can also be in ter preted as de - pos ited in the dis tal zone of so-called hochsander fans (Krüger, 1997; Ev ans and Twigg, 2002; Kj³r et al., 2004).
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 245
Fig. 13. Sec tion in the south ern and west ern parts of the Go³¹bek II sand pit
A and C – pho to graphs of the sec tion; B and D – cor re spond ing sed i men tary logs; for lo ca tion see Fig ure 8;
for ex pla na tion of the lithofacies codes see Ta bles 1 and 2; other ex pla na tions as in Fig ures 5–7 and 9
The thick trough, pla nar and hor i zon tally strat i fied sands with ad mix tures of gravel, which form as so ci a tion 6, are charcteristic of sandurs (Miall, 1977, 1985; Maizels, 1993;
Krüger, 1997; Krzyszkowski and Zieliñski, 2002; Zieliñski and van Loon, 2003; Kj³r et al., 2004). These de pos its are sim i lar to the low er most de pos its in the Go³¹bek I sand pit (lithofacies as - so ci a tion 1). It is note wor thy that the trough cross-strat i fied units are very well-de vel oped in both the Go³¹bek I and the Go³¹bek II sand pits (Figs. 5, 12 and 13).
Lithofacies as so ci a tion 7, with its hor i zon tally strat i fied silts and sands, was de pos ited in an ephem eral lake. These de - pos its are more dis tal than the glaciolacustrine de pos its from the Go³¹bek I sand pit (lithofacies as so ci a tion 2). They, too, set tled from sus pen sion or in a low-en ergy wa ter cur rent dur ing a sea son-de pend ent pe riod of lim ited ab la tion of the ice sheet (cf. Gruszka and Zieliñski, 1996; Gruszka, 2001, 2007;
Mokhtari Fard and Gruszka, 2007). These glaciolacustrine de - pos its were de formed by the over ly ing flow tills and mas sive grav els. Both these flow tills and mas sive grav els are in ter - preted as de bris flows (Nemec and Steel, 1984; Costa, 1988;
van Loon, 2009). How ever, the glaciolacustrine de pos its interfinger with glaciodeltaic de pos its, which are rep re sented by pla nar strat i fied sands. Such a sit u a tion is quite com mon in proglacial en vi ron ments, where a delta prograded into a lake (e.g., Smith and Ashley, 1985; Hansen et al., 2009).
GO£¥BEK III
The Go³¹bek III sand pit is 200 m long and 110 m wide. It is lo cated ~107–112 m a.s.l. (Fig. 14). The sedimentology of two
pro files are de scribed. They con sist of only four lithofacies, which are grouped into two as so ci a tions (Figs. 15 and 16).
D e s c r i p t i o n. – As men tioned above, only two lithofacies as so ci a tions are pres ent in this sand pit.
Lithofacies as so ci a tion 1 is com posed of large-scale pla nar cross-strat i fied sands and silts (Sp, Tp), which dom i nate the Go³¹bek III sand pit. The sands and silts al ter nate rhyth mi cally.
Their bases and tops are sed i men tary (non-ero sional, not de - formed), run ning par al lel to each other (Figs. 15 and 16). The strata look al most hor i zon tal in a N–S cross-sec tion (Figs. 15A, B and 16A), but dip at about 10–15° to wards the east in an E–W cross-sec tion (Fig. 15A, C). The suc ces sion ex tends lat er - ally for ~200 m and is 5 m thick. It is char ac ter ized by a pre -
Fig. 14. Out line of the Go³¹bek III sand pit with lo ca tion of the sed i men tary pro files shown in Fig ures 15 and 16
Fig. 15. Sec tion in the south east ern part of the Go³¹bek III sand pit
A – gen eral ar chi tec ture; B and C – lithofacies de scribed in de tail in the text and in Ta ble 2; for lo ca tion see Fig ure 14;
for ex pla na tion of the lithofacies codes see Ta bles 1 and 2; other ex pla na tions as in Fig ures 5 and 6
dom i nance of in verse grad ing, and the pre ferred palaeocurrent di rec tion is to wards the east (Fig. 16B).
Lithofacies as so ci a tion 2 con sists of mas sive sands, lo cally with or ganic ma te rial (Sm, SCm). These two lithofacies are found at the top of each co-set de scribed above, i.e. Sp and Tp (Fig. 16). In di vid ual strata are less than 0.6 m thick, but their hor i zon tal ex tent reaches up to 200 m. It is note wor thy that this suc ces sion con tains an ad mix ture of or ganic mat ter (Fig. 16B).
I n t e r p r e t a t i o n. – The two lithofacies as so ci a tions are in ter preted as fol lows.
As so ci a tion Sp, Tp is used as a pro to type of al lu vial-fan lithofacies as sem blages (Blair and McPherson, 1994; Blair, 1999; Shukla, 2009). Tak ing its palaeogeographical po si tion into con sid er ation, this as so ci a tion rep re sents a terminoglacial fan (Zieliñski and van Loon, 2000, 2003; Krzyszkowski and Zieliñski, 2002). These large-scale de pos its are a con tin u a tion, sev eral tens of metres to the east, of the de pos its in the Go³¹bek II sand pit de scribed as large-scale sands with a pla nar struc ture (lithofacies as so ci a tion 3). The de pos its are struc tur - ally the same, but they dif fer in grain size, i.e. they con tain equal pro por tions of sand and silt. There fore, this lithofacies as so ci a tion (Sp, Tp), can be con sid ered to be a re sult of de po si - tion by sheetfloods. The wa ter was not channelized and the cur - rent con di tions were rhyth mi cally chang ing from low-en ergy to very low-en ergy (cf. Zieliñski and van Loon, 2000). On the other hand, the rhythms can re flect chang ing in fluxes of sed i - ments, which in turn must be as cribed to pro cesses in the supraglacial source area such as ab la tion, in flux of rain wa ter, sud den drain age of pock ets of wa ter or re work ing of de bris (e.g., Krüger, 1994, 1997; Kj³r et al., 2004). Thus, the de pos its likely formed in the prox i mal part of a mid dle glaciofluvial fan (cf. Zieliñski and van Loon, 2000) or in the dis tal zone of a
hochsander fan (Krüger, 1997; Ev ans and Twigg, 2002; Kj³r et al., 2004). It is note wor thy that the large-scale pla nar strat i fi - ca tion dips 10–15°, al though the slope gra di ent (= large-scale pla nar strat i fi ca tion) ranges, in the case of an or di nary hochsander fan, from 1 to 5° (Krüger, 1997; Kj³r et al., 2004).
The sec ond as so ci a tion, with mas sive sands, ei ther with or with out or ganic ma te rial, is char ac ter is tic of palaeosoils, which in di cate a hi a tus in the de vel op ment of the glaciofluvial fan. It is pos si ble to dis tin guish, in a ver ti cal pro file, at least four gen - er a tions of the fan in the Go³¹bek III sand pit (Zieliñski et al., 2009). The mas sive struc ture is prob a bly a re sult of sandy sheetfloods and/or bioturbation (Shukla, 2009; van Loon, 2009). In the lat ter case the plant roots cre ate, ac cord ing to these re search ers, spe cial re dox con di tions, and can af fect the orig i nal strat i fi ca tion. More over, the re sult ing or ganic mat ter from de com posed plants can be found if they were rap idly cov - ered with new de pos its (van Loon, 2009).
SEDIMENTOLOGICAL MODEL
On the ba sis of the above geomorphological and sedimentological con sid er ations, a new con cep tual model of the Z³ota Góra Mas sif evo lu tion is pro posed (Fig. 17). It is ob vi ously more rep re sen ta tive and re al is tic for the north ern seg ment, where the de tailed sedimentological in ves ti ga tions were car ried out. In con trast, this model is more con cep tual for the cen tral and south - ern seg ments of the Z³ota Góra Mas sif, where it is mainly based on geo mor phol ogy, sur face ob ser va tions as well as geo log i cal map ping (Gogo³ek and Mañkowska, 1989). The pres ent model dis tin guishes four main phases, dur ing which the land forms un - der study with their lithofacies were formed (Ta ble 2).
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 247
Fig. 16. Sec tion in the east ern parts of the Go³¹bek III sand pit
A – pho to graph of the sec tion; B – cor re spond ing sed i men tary log; for lo ca tion see Fig ure 14; for leg end see Fig ure 7;
for ex pla na tion of the lithofacies codes see Ta bles 1 and 2; other ex pla na tions as in Fig ure 5
The south ern part of the study area was formed dur ing the first phase. Sev eral small ter mi nal-mo raine fans, with rel a tively steep south ern slopes, were built along the ice front, with their apexes touch ing the ice mar gin (Fig. 17A). These fans were sit - u ated par al lel to each other, what sug gests ac tive ice re treat ing for a few hun dred metres. In this way, a belt of ter mi nal mo - raines, con sist ing of stacked glaciofluvial and gla cial de pos its, was cre ated. The south ern part of the Z³ota Góra Mas sif thus rep re sents a ter mi nal mo raine of mixed glaciofluvial/gla cial type (Fig. 17A).
Dur ing the sec ond phase, de po si tion took place be tween two ma jor ice sheet lobes, prob a bly above a pre-ex ist ing high in the sub stra tum (Fig. 17B). Z³ota Góra was then formed. Its sur face is cov ered by diamictons, “egg grav els” and sands and “nor mal”
grav els. The top of Z³ota Góra can thus be con sid ered as a ter mi - nal-mo raine fan. Con versely, the huge and flat-topped area south of Z³ota Góra can be in ter preted as an elon gated sandur fan (Fig. 17B). Its shape, with steep west ern and east ern slopes, sug - gests that flu vio gla cial de po si tion took place in an ice-walled ac - cu mu la tion space, i.e. in an interlobe area.
The third phase is a rep e ti tion of the sec ond one, but at a smaller scale. Dur ing this stage of deglaciation, at least five
small hills were formed (Fig. 17C). The lithofacies ar chi tec ture in di cates some os cil la tions of the ice sheet mar gin. In gen eral, the hills must be con sid ered to form a com bi na tion of the ter mi - nal mo raine and sandur fans (Fig. 17C).
The last phase is con nected with the deglaciation of the study area. Ero sion of the steep slopes oc curred, and the Warszawa–Berlin ice-mar ginal streamway came into ex is tence si mul ta neously (Fig. 17D). Fi nally, the pres ent-day drain age net work was formed (see Fig. 2).
DISCUSSION
In gen eral, most depositional glacigenic land forms are com posed of sim i lar de pos its in vary ing pro por tions, but each is char ac ter ized by an in di vid ual mor phol ogy and in te rior ar - chi tec ture (Ev ans et al., 1999; Ev ans and Twigg, 2002). The size, shape, li thol ogy, depositional con di tions, palaeocurrent pat terns and de for ma tions of these land forms are, there fore, dis cussed be low in the fol low ing or der: kame, sandur and ter - mi nal mo raine.
Fig. 17. Con cep tual model for the geomorphological de vel op ment of the Z³ota Góra Mas sif
The ba sis of a kame may be cir cu lar, len tic u lar, ir reg u lar, etc.
Tak ing into con sid er ation kame for ma tion in a low land area, it can be con cluded that de po si tion must have taken place in cre - vasses or de pres sions sur rounded by dead-ice (Bartkowski, 1967) or be tween ice-cored mo raines (Boulton, 1972). In most cases, the palaeocurrent pat tern is cen trip e tal, i.e. the kame ma te - rial was de pos ited by wa ter run ning to wards the cen tral zone of the cre vasses or de pres sions (Klajnert, 1984). How ever, in the case of the Z³ota Góra Mas sif, mea sure ments do not in di cate trans port di rec tions to wards the N, NW and NE. Sim i lar ob ser - va tions were made dur ing con struc tion of the A2 high way (Poznañ–Konin–Warszawa), which cuts the study area south of the Z³ota Góra top. These pre lim i nary ob ser va tions pro vided sim i lar re sults to the above-men tioned, i.e. the trans port pre dom - i nantly was di rected to wards the south in the cen tral seg ment of the Z³ota Góra Mas sif. Thus, tak ing all in for ma tion into con sid - er ation, the in ves ti gated land forms can not be re garded as kames, as was sug gested by K³ysz (1981, 1985).
The term “sandur” or “interlobate sandur fan” can not be used for the hills and for the en tire Z³ota Góra Mas sif, as did Widera (1993). It is true that most of the sed i ments in the Go³¹bek I and Go³¹bek II sand pits rep re sent lithofacies typ i cal of sandurs, viz. the (glaciofluvial) braided-river en vi ron ment (Krüger, 1997; Zieliñski and van Loon, 2000; Kj³r et al., 2004). The mor phol ogy of the above land forms, where the west ern, north ern and east ern slopes are very steep, in di cates also sed i men ta tion be tween ice sheet lobes (see Figs. 2 and 17).
How ever, the lithofacies that were dis tin guished are char ac ter - is tic of end mo raines: flow tills and glaciofluvial-fan de pos its.
More over, the pres ence of so-called “egg grav els” on the top of Z³ota Góra in di cates that the en tire mas sif can not be in ter preted as a sandur or an “interlobate sandur fan”.
For geomorphological and sedimentological rea sons the Z³ota Góra Mas sif, in clud ing the hills in its north ern seg ment, can not be con sid ered as a ter mi nal mo raine (Petera and Forysiak, 2003; Marks et al., 2006; and ref er ences therein).
Only the south ern, the north ern and the north-cen tral parts of the Z³ota Góra Mas sif may be con sid ered as a ter mi nal mo raine (see Fig. 17). De pos its char ac ter is tic of ter mi nal mo raines have been de scribed in de tail from the north ern and up per parts of the Go³¹bek I and Go³¹bek II sand pits. How ever, all de pos its from the Go³¹bek III sand pit are char ac ter is tic of an al lu vial (glaciofluvial) fan. In con trast to sandur sed i ments dom i nated by de po si tion in a braided river, these ter mi nal-mo raine de pos - its re sult from de bris flows, sheetfloods and/or hyperconcentrated flows. Gen er ally, they rep re sent a glaciofluvial/gla cial type of ter mi nal-mo raine fan. Zieliñski and van Loon (2000) stated: “...Pleis to cene sandur de pos its rep re sent braidplains, not al lu vial fans...”. Here, it is sug gested that the glaciofluvial fan rep re sents a ter mi nal mo raine, whereas the braidplain de pos its rep re sent a sandur. The Z³ota Góra Mas sif can con se quently not be con sid ered in its en tirety as a ter mi nal mo raine, as is done on the most re cent geo log i cal map of Po land at 1:500 000 scale (Marks et al., 2006).
It seems that the Z³ota Góra Mas sif re sults from a com bi na - tion of fac tors. The data in di cate that the en tire mas sif is com - posed of ter mi nal mo raines and sandurs, which were formed be - tween ice sheet lobes. Such a sit u a tion prob a bly took place along a con tact zone of the Odra lobe (Marks, 2002; Przybylski, 2008)
and the Vistula lobe (Marks, 2002; Morawski, 2009). The Z³ota Góra Mas sif should, there fore, be re garded as a tri ple ter mi - nal-mo raine/sandur com plex. Partly sim i lar ice-mar ginal land - forms are de scribed from the Kötlujökull by Krüger (1997), and from the Breijamerkurjökull and Fjallsjökull (all in Ice land) by Ev ans and Twigg (2002).
CONCLUSIONS
The or i gin of the Z³ota Góra Mas sif in Cen tral Po land was in ves ti gated on the ba sis of its geo mor phol ogy and sedimentology. The mas sif con sists of three parts, each con sist - ing of asym met ri cal and oval-shaped hills which dif fer in shape and size. They have three flanks that are rel a tively steep, which was in ter preted as the ef fect of ac cu mu la tion be tween lobes of the re treat ing Scan di na vian ice sheet.
The or i gin of the interlobate land forms is ex plained on the ba sis of sedimentological anal y ses in three sand pits, i.e.
Go³¹bek I, II and III. The re sults show a di ver sity of lithofacies, which can be rec og nized as char ac ter is tic of a sandur or a ter - mi nal mo raine. Ad di tion ally, some lithofacies in di cate de po si - tion in ephem eral lakes.
The sandur-re lated lithofacies were formed in braided rivers.
These de pos its are dom i nant in the cen tral and south ern parts of the Go³¹bek I and Go³¹bek II sand pits. The lithofacies re lated to a ter mi nal mo raine were de pos ited mainly by de bris and hyperconcentrated flows and/or sheetfloods. Both the de - bris-flow and sheetflood lithofacies are pres ent in the most north ern and up per parts of the Go³¹bek I and Go³¹bek II sand pits. It must be noted in this con text that all lithofacies in the Go³¹bek III sand pit were pro duced by sheetfloods. The ephem - eral lake-re lated lithofacies oc cur in both the sandur and the tereminal-mo raine ar eas. These glaciolacustrine de pos its are of - ten de formed at their top by the over ly ing de bris-flow de pos its.
Lithofacies char ac ter is tics of a delta are also pres ent. They are spa tially re lated to both the ephem eral lakes and the sandur.
A large num ber of mea sure ments in di cate that the palaeocurrent di rec tion was di rected pre dom i nantly to wards the south. Tak ing the geo mor phol ogy and sedimentology into ac count, the hills of the Z³ota Góra thus rep re sent a mo - raine/sandur mas sif. It was built in the area where the Odra and Vistula ice lobes prob a bly met. The “fresh” mor phol ogy and the lack of ventifacts sup port a Weichselian age of the land - forms. How ever, an older age of the Z³ota Góra Mas sif can not be re jected def i nitely and, there fore, fur ther in ves ti ga tions are rec om mended.
Ac knowl edge ments. The au thor thanks T. Zieliñski for his valu able con tri bu tion to the in ter pre ta tion of some lithofacies, his pleas ant com pany and the fruit ful dis cus sions in the field. J. Krüger and two anon y mous re view ers are grate - fully ac knowl edged for pro vid ing crit i cal but con struc tive re - marks, which im proved the pres ent con tri bu tion sig nif i cantly.
The au thor is also in debted to T. van Loon for cor rect ing the Eng lish of the fi nal ver sion. Last but not least, K. Janiak and J.
Staszak are thanked for per mit ting to con duct field work on their prop erty.
Geomorphology, sedimentology and origin of the glacigenic Z³ota Góra hills near Konin (Central Poland) 249
REFERENCES
ALLEN J. R. L. (1965) – A re view of the or i gin and char ac ter is tics of re - cent al lu vial sed i ments. Sedimentology, 5: 89–191.
ALLEN J. R. L. (1970) – The avalanching of gran u lar sol ids on dune and sim i lar slopes. J. Geol., 73: 95–116.
BARTKOWSKI T. (1967) – Sur les formes de la zone marginale dans la Plain de Grande Pologne (in Pol ish with French sum mary). Pozn. Tow.
Przyj. Nauk., Pr. Kom. Geograf.-Geol., 7.
BERENDT G. and KEILHACK K. (1894) – Endmoränen in der Provinz Posen. Jb. D. Kön. Preuss. Geol. Landesanst., 13: 235–237.
BLAIR T. C. (1999) – Sedimentology of de bris-flow-dom i nated warm spring Can yon al lu vial fan, Death Val ley, Cal i for nia. Sedimentology, 46: 941–965.
BLAIR T. C. and McPHERSON J. G. (1994) – Al lu vial fans and their nat u - ral dis tinc tion from rivers based on mor phol ogy, hy drau lic pro cesses, sed i men tary pro cesses, and their fa cies as sem blages. J. Sed i ment.
Res., 64A: 450–489.
BOULTON G. S. (1972) – Mod ern Arc tic gla ciers as depositional mod els for for mer ice sheets. J. Geol. Soc. Lon don, 128: 361–393.
BRODZIKOWSKI K. and van LOON A. J. (1987) – A sys tem atic clas si fi - ca tion of gla cial and periglacial en vi ron ments, fa cies and de pos its.
Earth Sc. Rev., 24: 297–381.
COSTA J. E. (1988) – Rheologic, geomorphic, and sedimentologic dif fer - en ti a tion of wa ter floods, hyperconcentrated flows, and de bris flows.
In: Flood Geo mor phol ogy (eds. V. R. Baker, R. C. Kochel and P. C.
Patton): 113–122. Wiley, New York.
EVANS D. J. A., LEMMEN D. S. and BRICE R. R. (1999) – Gla cial landsystems of the south west Laurentide Ice Sheet: mod ern Ice lan dic an a logues. J. Quatern. Sc., 14: 673–691.
EVANS D. J. A. and TWIGG D. R. (2002) – The ac tive tem per ate gla cial landsystem: a model based on Breijamerkurjökull and Fjallsjökull, Ice land. Quatern. Sc. Rev., 21: 2143–2177.
EYLES N., EYLES C. H. and MIALL A. D. (1983) – Lithofacies types and ver ti cal pro file mod els; an al ter na tive ap proach to the de scrip tion and en vi ron men tal in ter pre ta tion of gla cial diamict and diamictite se - quences. Sedimentology, 30: 393–410.
GLASSER N. F., BENNETT M. R. and HUDDART D. (1999) – Dis tri bu - tion of glaciofluvial sed i ment within and on the sur face of a high arc tic val ley gla cier: Marthabreen, Svalbard. Earth Sur face Pro cesses and Land forms, 24: 303–318.
GOGO£EK W. and MAÑKOWSKA A. (1989) – Vistulian of the Turek Up land in the light of new data (in Pol ish with Eng lish sum mary).
Geol. Quart., 33 (3–4): 573–586.
GRUSZKA B. (2001) – Cli ma tic ver sus tec tonic fac tors in the for ma tion of the glaciolacustrine suc ces sion (Be³chatów out crop, cen tral Po land).
Global and Plan e tary Change, 28: 53–71.
GRUSZKA B. (2007) – The Pleis to cene glaciolacustrine sed i ments in the Belchatow mine (cen tral Po land): endogenic and exo gen ic con trols.
Sed i ment. Geol., 193: 149–166.
GRUSZKA B. and ZIELIÑSKI T. (1996) – Grav ity flow or i gin of glaciolacustrine sed i ments in a tec toni cally ac tive ba sin (Pleis to cene, Cen tral Po land). Ann. Soc. Geol. Pol., 66 (1): 59–81.
HANSEN L., BEYLICH A., BURKI V., EILERTSEN R. S., FREDIN O., LARSEN E., LYSC A., NESJE A., STALSBERG K. and TNNESEN J. F. (2009) – Strati graphic ar chi tec ture and infill his tory of a deglaciated bed rock val ley based on georadar, seis mic pro fil ing and drill ing. Sedimentology, 56: 1751–1773.
HUDDART D., BENNETT M. R. and GLASSER N. F. (1999) – Mor phol - ogy and sedimentology of a high-arc tic esker sys tem: Vegbreen, Svalbard. Boreas, 28: 253–273.
KARCZEWSKI A. (1994) – Morpho- and lithogenetic di ver si fi ca tion of the Pom er a nian Phase in west ern and cen tral Pomerania. Zeitschrift fur Geomorphologie, N.F., 95: 35–48.
KASPRZAK L. and KOZARSKI S. (1984) – Analiza facjalna osadów strefy marginalnej fazy poznañskiej ostatniego zlodowacenia w œrodkowej Wielkopolsce. UAM, Ser. Geogr., 24.
KASPRZAK L. and KOZARSKI S. (1989) – Ice-lobe con tact sed i men tary scarps in mar ginal zones of the ma jor Vistulian ice-sheet po si tions, west-cen tral Po land. Quaest. Geogr., 2: 69–81.
KJR K. H., SULTANA L., KRÜGER J. and SCHOMACKER A. (2004) – Ar chi tec ture and sed i men ta tion of outwash fans in front of the Mýrdalsjfkull ice cap, Ice land. Sed i ment. Geol., 172: 139–163.
KLAJNERT Z. (1984) – Anal y sis of kames for palaeo geo graphi cal re con - struc tions. Boreas, 113: 95–109.
KLEINHANS M. G. (2001) – The key role of flu vial dunes in trans port and de po si tion of sand-gravel mix ture, a pre lim i nary note. Sed i ment.
Geol., 143: 7–13.
K£YSZ P. (1981) – Morphogenesis of a se quence of mar ginal forms in the sur round ings of Konin, Ko³o and Turek (in Pol ish with Eng lish sum - mary). UAM, Ser. Geogr., 23.
K£YSZ P. (1985) –– Pre-Vistulian mar ginal forms in the Konin Re gion.
Quatern. Stud. Pol., 6: 55–82.
KNUDSEN Ó. and MARREN Ph. M. (2002) – Sed i men ta tion in a vol ca ni - cally dammed val ley, Brúarjökull, north east Ice land. Quatern. Sc.
Rev., 21: 1677–1692.
KOZARSKI S. (1981) – Stratygrafia i chronologia vistulianu Niziny Wielkopolskiej. Geografia, 4. PWN.
KOZARSKI S. (1986) – Skale czasu a rytm zdarzeñ geomorfologicznych vistulianu na Ni¿u Polskim. Czas. Geogr., 57 (2): 247–270.
KOZARSKI S. (1990) – Ab la tion sed i ments of the last gla ci ation in W.
Cen tral Po land: iden ti fi ca tion and palaeo geo graphi cal im pli ca tions.
Acta Univ. Wratisl., 1056, Pr. Inst. Geogr. Ser. A, 4: 41–60.
KRÜGER J. (1994) – Gla cial pro cesses, sed i ments, land forms, and stra tig - ra phy in the ter mi nus re gion of Mýrdalsjökull, Ice land. Folia Geogr.
Dan., 21: 1–233.
KRÜGER J. (1997) – De vel op ment of mi nor outwash fans at Kötlujökull, Ice land. Quatern. Sc. Rev., 16: 649–659.
KRÜGER J. and MARCUSSEN I. (1976) – Lodge ment till and flow till: a dis cus sion. Boreas, 5: 61–64.
KRÜGER J., SCHOMACKER A. and BENEDIKTSSON Í. Ö. (2010) – Ice mar ginal en vi ron ments: geomorphic and struc tural gen e sis of mar - ginal mo raines at Mýrdalsjökull. De velop. Quatern. Sc., 13: 79–104.
KRYGOWSKI B. (1974) – Niektóre problemy z morfodynamiki Niziny Wielkopolskiej. Bad. Fizjogr. Pol. Zach., 27: 89–149.
KRZYSZKOWSKI D. and ZIELIÑSKI T. (2002) – The Pleis to cene end mo raine fans: con trols on their sed i men ta tion and lo ca tion. Sed i ment.
Geol., 149 (1–3): 73–92.
KRZYWICKI T. (2002) – The max i mum ice sheet limit of the Vistulian Gla ci ation in north east ern Po land and neigh bour ing ar eas. Geol.
Quart., 46 (2): 165–188.
LENCEWICZ S. (1927) – Gla ci ation et morphologie du bassin de la Vistule moyenne (in Pol ish with French sum mary). Pr. Pañstw. Inst.
Geol., 2.
£YCZEWSKA J. (1960) – Re marks on the Qua ter nary of east ern Kujawy (in Pol ish with Eng lish sum mary). Biul. Inst. Geol., 150: 245–255.
MAIZELS J. K. (1993) – Lithofacies vari a tions within sandur de pos its: the role of run off re gime, flow dy nam ics and sed i ment sup ply char ac ter is - tics. Sed i ment. Geol., 85: 299–325.
MAJDANOWSKI S. (1950) – The prob lem of lake-chan nels in the Eu ro - pean Plain (in Pol ish with Eng lish sum mary). Bad. Fizjogr. Pozn. TPN, 2 (1): 35–122.
MARKS L. (2002) – Last Gla cial Max i mum in Po land. Quatern. Sc. Rev., 21: 103–110.
MARKS L. (2005) – Pleis to cene gla cial lim its in the ter ri tory of Po land (in Pol ish with Eng lish sum mary). Prz. Geol., 53: (10/2) 988–993.
MARKS L., BER A., GOGO£EK W. and PIOTROWSKA K. (2006) – Mapa geologiczna Polski w skali 1:500 000. Pañstw. Inst. Geol., Warszawa.
MIALL A. D. (1977) – A re view of the braided-river depositional en vi ron - ment. Earth Sc. Rev., 13: 1–62.
MIALL A. D. (1985) – Ar chi tec tural el e ment anal y sis: a new method of fa - cies anal y sis ap plied to flu vial de pos its. Earth Sc. Rev., 22: 261–308.
MIKO£AJSKI J. (1927) – O powstaniu tzw. pradoliny warszawsko-berliñskiej. Bad. Geogr., 2/3: 53–98.
MOKHTARI FARD A. and GRUSZKA B. (2007) – Subglacial con di tions in a branch ing Saalian esker in north-cen tral Po land. Sed i ment. Geol., 193: 33–46.
MORAWSKI W. (1999) – Max i mum limit of the Vistulian Gla ci ation in the vi cin ity of Nidzica, south west ern Mazury Lakeland. Geol. Quart., 43 (1) 61–68.
MORAWSKI W. (2009) – Re con struc tion of the Vistula ice stream dur ing the Last Gla cial Max i mum in Po land. Geol. Quart., 53 (3): 305–316.
NEMEC W. and STEEL R. J. (1984) – Al lu vial and coastal con glom er ates:
their sig nif i cant fea tures and some com ments on grav elly mass-flow de pos its. In: Sedimentology of Grav els and Con glom er ates (eds. E. H.
Koster and R. J. Steel). Can. Soc. Petrol. Geol. Mem., 10: 1–31.
PAUL M. A. and EYLES N. (1990) – Con straints on the pres er va tion of diamict fa cies (melt-out tills) at the mar gins of stag nant gla ciers.
Quatern. Sc. Rev., 9: 51–69.
PETERA J. and FORYSIAK J. (2003) – The prob lem of the Last Gla ci ation ex tent in Cen tral Po land. Geol. Quart., 47 (4): 357–366.
PISARSKA-JAMRO¯Y M. (2006) – Tran si tional de pos its be tween the end mo raine and outwash plain in the Pom er a nian glaciomarginal zone of NW Po land: a miss ing com po nent of ice-con tact sed i men tary mod - els. Boreas, 35 (1): 126–141.
PISARSKA-JAMRO¯Y M. (2007) – Glaciofluvial fa cies of hyperconcentrated flow (the Pleis to cene of Den mark and West ern Pomerania) (in Pol ish with Eng lish sum mary). Prz. Geol., 55 (6):
503–510.
PRZYBYLSKI B. (2008) – Geomorphic traces of a Weichselian ice stream in the Wielkopolska Low land, west ern Po land. Boreas, 37 (7): 286–296.
ROTNICKI K. (1963) – Ex tent of Leszno and Poznañ stages in south-east part of Gniezno Pleis to cene Pla teau, East Great Po land (in Pol ish with Eng lish sum mary). Bad. Fizjogr. Pol. Zach., 11: 133–184.
ROTNICKI K. and BORÓWKA R. K. (1990) – New data on the age of the max i mum ad vance of the Vistulian ice sheet dur ing the Leszno Phase.
Quatern. Stud., 9: 73–83.
RUSZCZYÑSKA-SZENAJCH H. (1982) – Depositional pro cesses of Pleis to cene low land end mo raines, and their pos si ble re la tion to cli ma - tic con di tions. Boreas, 11 (3): 249–260.
SHUKLA U. K. (2009) – Sed i men ta tion model of gravel-dom i nated al lu - vial piedmont fan, Gan ga Plain, In dia. Internat. J. Earth Sc., 98:
443–459.
SMITH N. D. and ASHLEY G. M. (1985) – Proglacial lac us trine en vi ron - ment. In: Gla cial Sed i men tary En vi ron ment (eds. G. M. Ashley et al.).
SEPM Short Course, 16: 135–216.
STANKOWSKA A. and STANKOWSKI W. (1988) – Max i mum ex tent of the Vistulian ice sheet in the vi cin ity of Konin, Po land: a geomorphologic, sedimentological and ra dio met ric ev i dence. Geogr.
Pol., 55: 141–150.
STANKOWSKI W., BIEDROWSKI Z., STANKOWSKA A., KO£ODZIEJ G., WIDERA M. and WILKOSZ P. (1995) – Caino zo ic of the Konin area with spe cial em pha sis on the stra tig ra phy of Qua ter - nary de pos its. Quatern. Stud., 13: 101–108.
SZA£AMACHA G. and SKOMPSKI S. (1999) – Biogenic sed i ments of the Eemian Inter gla cial at Krzy¿ówki near Ko³o, cen tral Po land. Geol.
Quart., 43 (1): 99–105.
Van LOON A. J. (2009) – Soft-sed i ment de for ma tion struc tures in siliciclastic sed i ments: an over view. Geologos, 15: 3–55.
WIDERA M. (1993) –– Charakterystyka litologiczna osadów czwartorzêdowych na pó³nocnych zboczach Z³otej Góry ko³o Konina.
Msc The sis, Arch. Inst. Geol. UAM, Poznañ.
WIDERA M. (2000) – Stra tig ra phy and li thol ogy of Qua ter nary sed i ments in the Kleczew re gion and in key sec tions of the east ern Wielkopolska Low land, cen tral Po land. Geol. Quart., 44 (2): 211–220.
WOLDSTEDT P. (1931) – Über Randlagen der letzten Vereisung in Ostdeutschland und Polen und über die Herausbildung des Netze-Warthe Urstromtales. Jb. D. Preuss. Geol. Landesanst., 52:
59–67.
WYSOTA W. (1999) – Ice sheet max i mum limit of the Vistulian Gla ci ation in the mid-east ern Che³mno–Dobrzyñ Lakeland, north ern Po land.
Geol. Quart., 43 (2): 189–202.
ZIELIÑSKI T. and van LOON A. J. (1996) – Char ac ter is tics and gen e sis of mo raine-de rived flowtill va ri et ies. Sed i ment. Geol., 101 (1–2): 119–143.
ZIELIÑSKI T. and van LOON A. J. (2000) – Subaerial terminoglacial fans III: over view of sed i men tary char ac ter is tics and depositional model.
Geol. en Mijnbouw, 79 (1): 93–107.
ZIELIÑSKI T. and van LOON A. J. (2003) – Pleis to cene sandur de pos its rep re sent braidplains, not al lu vial fans. Boreas, 32 (4): 590–611.
ZIELIÑSKI T., WIDERA M. and GRUSZKA B. (2009) – Okolice Konina i Turku. Stanowiska Go³¹bek. In: Geologia kenozoiku Ni¿u Polskiego.
Przewodnik do æwiczeñ terenowych z geologii kenozoiku i geomorfologii (ed. M. Widera): 99–105. Wyd. Nauk. UAM, Poznañ.
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