Dated landslides of the Jaworzyna Krynicka Range (Polish Carpathians) and their relation to climatic phases of the Holocene

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A nn ales S o cieta tis G eologoru m P olon iae (1997), vol. 67: 83-92.

DATED LANDSLIDES OF THE JAWORZYNA KRYNICKA RANGE (POLISH OUTER CARPATHIANS) AND THEIR RELATION

TO CLIMATIC PHASES OF THE HOLOCENE

Włodzimierz MARGIELEWSKI

I n s titu te o f N a tu r e C o n s e r v a tio n , P o lis h A c a d e m y o f S c ie n c e s , ul. L u b ic z 4 6 , 3 1 - 5 1 2 K r a k ó w , P o l a n d

Margielewski, W., 1997. Dated landslides o f the Jaworzyna Krynicka Range (Polish Outer Carpathians) and their relation to climatic phases o f the Holocene. Ann. Soc. Geol. P olon ., 67: 83-92.

Abstract: Ten radiocarbon datings o f landslides o f the Jaworzyna Krynicka Range, were performed to establish the date o f their formation or rejuvenation. These datings widen the documentation o f the landslide phases connected with humid periods o f the Holocene. Several dates correspond to landslide phases and prove that the landslides were formed at the beginning o f the Atlantic Phase, termination o f the Subboreal Phase, in the Middle Ages and at the beginning o f the Little Ice Age. A landslide phase o f mass movement intensification connected with a humid phase at the beginning o f the Subboreal Phase is based on two radiocarbon datings. Five radiocarbon dates confirm the relationship between mass movement intensification and a humid phase distinguished at early Subatlantic Phase.

Abstrakt: W obrębie osuwisk pasma Jaworzyny Krynickiej wykonano dziesięć datowań radiowęglowych, po

zwalających na określenie czasu powstania lub odmłodzenia tych form. Datowania te znacznie poszerzają doku

mentację faz osuwiskowych w Karpatach, wiązanych z okresami holoceńskich zwilgoceń. Część uzyskanych dat dokumentuje okresy intensyfikacji osuwisk wydzielane na początku fazy atlantyckiej, w schyłkowym okresie subboreału oraz w średniowieczu, we wczesnej fazie malej epoki lodowej. Faza osuwiskowa wiązana z okresem wilgotnym na początku subboreału jest potwierdzona dwoma datowaniami. Pięć datowań radiowęglowych po

twierdza związek intensyfikacji ruchów masowych z fazązw ilgocenia wydzielaną w e wczesnym subatlantyku.

Key words: Polish Outer Carpathians, Holocene, mass movements, radiocarbon datings, landslide phases.

M an uscript r e c e iv e d 10 June 1996, a c c e p te d 5 F ebruary 1997

INTRODUCTION

M ass m ovem en ts are am ong the prevailing p rocesses in r e lie f ev o lu tio n o f the C arpathians b ecau se o f their charac

teristic g eo lo g ica l structure (Starkel, 1960; Ziętara, 1962, 1964; N e m ć o k , 1982; B ober, 1984; Kotarba, 1986). T he in

ten sity o f th ese p rocesses w a s con n ected w ith hum id periods in the H o lo c e n e w h ich indicates the periodic d evelop m en t o f the B esk id y M ts r e lie f (Starkel, 1985, 1986, 1990). The age o f th e m ass m o v em en ts has not been appropriately e s

tablished. T he relatively sm all num ber o f p recisely dated landslide sedim ents has until n ow m ade the task o f recon  structing and d ocum entating the landslide phases in the Car

pathians particularly d ifficu lt. T his fact is con n ected w ith d ifficu lties in gain in g o f proper m aterial for dating. Palino- logical, m a la co lo g ica l or radiocarbon an alyses o f organic sed im en ts w ere used w h en determ ining the age o f the Car

pathian landslides. T h ese sedim ents fill up the depressions w ithin the landslides or occur in barrier lakes resulting from dam m ing up a river by the co llu v ia (G il e t a l., 1974; A lexan - drow icz, 1993b).

This paper presents eigh t landslide form s o f the Jaw o

rzyna K rynicka R ange (M agura N ap p e, P o lish Outer Carpa

thians), w here organic sed im en ts fill up the depressions (subniche or intercolluvial on es). T en radiocarbon dates ob  tained from w o o d occu rin g at the bottom o f th ese sedim ents a llo w ed to fix the date o f form ation or rejuvenation o f the landslides and en abled to su p p ly m ore co m p lete d o cu m en  tary ev id en ce for the m ass m o v em en t p h ases, d istinguished in the Carpathians by Starkel (1 9 8 5 ) and A lex a n d ro w icz (1993b ).

R adiocarbon datings w ere m ad e in the R adiocarbon La

boratory o f the Silesian T ech n ical U n iv ersity in G liw ice (G d) and in the Institute o f N u clea r P h y sics o f the A ca d em y o f M ining and M etallurgy in K raków (K r). A n a ly tica l costs w ere paid by the State C om m itee for S cien tific R esearch (K B N ) (research project 6P 2 0 2 0 0 7 0 4).

GEOLOGICAL SETTING

The Jaw orzyna K rynicka R an ge is the eastern fragm ent o f the B esk id Sądecki M ts, bordered by the v a lle y s o f the Poprad and the K am ien ica N a w o jo w sk a rivers. G e o lo g i

cally, it is situated w ithin the inner structural subunits o f the

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Fig. 1. D a ted la n d slid es o f the J a w o rzy n a K ryn ick a R ange and g e o lo g ic a l o v e r v ie w o f the reg io n (g e o lo g y after B irk en m ajer &

O sz c z y p k o , 1989; O sz c z y p k o , 1991). I - S z c z a w n ic a and Z a r zecze F orm ation s, 2 -B e lo v e z a F orm ation, 3 - P iw n ic z n a M em b er, M agura F orm ation , 4- M a s z k o w ic e M em b er, M agura F orm ation, 5 - K ry n ica overthrust, 6 - dated la n d slid es w ith p la c e m e n t o f sa m p le s for rad iocarb on a n a ly sis: 1 - C yrla, 2 - G aw orzyn a, 3 - J esio n o w a , 4 - S w in iarn ia, 5 - W ierch nad K a m ie n ie m , 6 - W ie r c h o m la 1 , 7 — W ie r c h o m la 2, 8 - W ie r c h o m la 3

M agura N appe: the S ą cz Subunit (B ystrica Subunit) and overthrusted from the south by the K rynica Subunit (S w i- dziński, 1953; W ęcław ik , 1969) (Fig. 1). The zon es con sist o f U pper C r e ta c e o u s-P a le o g e n e fly sch deposits (m ainly tur- bidite form ations) w h ich are about 3 0 0 0 m thick (B irkenm a

jer & O szczy p k o , 1989; O szczy p k o , 1991).

T he m ain ridge o f th e range is 1 0 0 0 m a.s.l.. It w as form ed o f the K rynica Subunit d eposits, represented by the P iw n iczn a Sandstone M em ber o f the M agura Formation (thick bed d ed sandstones p ackaged o f thin and m edium bed

ded fly sch ). It is underlained by fly sch sedim ents o f the Za

rzecze F on n ation , co n sistin g o f thin and m edium bedded sandstones w ith con glom erates and peb b le m udstones o f the K rynica M em ber (B irkenm ajer & O szczy p k o , 1989; O sz  czyp k o e t a l., 1990) (F ig. 1). T h ese deposits build the m ain g e o lo g ic a l structure o f this range, called R u n ek -Ł ab ow sk a H a la -P isa n a Hala S in clin e. Z arzecze form ation is under

lained b y the deposits o f th e S zcza w n ica Form ation repre

sented b y the con glom erates (Ż y cza n ó w M em ber), thin and m edium bedded flysch w ith dark shales (B irkenm ajer &

O szczyp k o, 1989; O szczy p k o e t a l., 1990). T he northern part o f the Jaw orzyna K rynicka R an ge (sid e ridges) is o c c u  pied b y the B ystrica Subunit, w h ich is d istin gu ish ed from the K rynica Subunit m ainly by the p resen ce o f the Ł ącko marls in the Ż eleźn ik o w a Form ation (thin and m edium bed

ded fly sch ) and M a szk o w ice M em b er o f the M agura Form a

tion (thick bedded sandstones p ackaged o f thin bedded fly sch ) (O szczy p k o , 1991) (F ig. 1).

LANDSLIDES OF THE JAWORZYNA KRYNICKA RANGE

M ass m ovem en ts p layed an im portant role in the r e lie f transform ation o f the Jaw orzyna K rynicka R ange. T hey caused its low erin g and d ism em bering. T he strong exp an 

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DATED LANDSLIDES OF THE JAWORZYNA KRYNICKA

85

sion o f v a lle y s and the d evelop m en t o f v a lle y head system s initiated th ese p rocesses. L andslide distribution is strictly dependend on the g e o lo g ic a l structure. Particularly tecton ic anisotrophy (fissu res) o f th e sandstone m assif, and changes o f lith o lo g y as w e ll as tech n ica l parameters o f the sand

ston es controll the distribution o f landslides (M argielew ski, 1997). In the Jaw orzyna K rynicka R ange th ey form num er

ous asso cia tio n s characterised by frequent su c c e ssiv e reju

venation (M argielew sk i, 1 994c). A ll o f the studied land

slid es represent a typ e o f structural rock slide. T hey w ere form ed in the sandstones o f the P iw n iczn a M em ber o f the M agura Form ation or w ith in sandstones and conglom erates o f the K rynica M em ber o f the Z arzecze Form ation (Fig. 1).

CYRLA LANDSLIDE

T he w id e m ass m o v em en t zon e w ith num erous land

slid es w a s form ed on the southern slop e o f M ount M ako- w ic a near R ytro (F ig. 1.1). In the central part o f the zon e there is a h illsid e, con seq u en t-slip landslide resulting from the lateral erosion o f the G łęb oczan k a stream. It has rela

tiv ely high, contem porarily creeped n ich e w ith typical mar

gin troughs. Varied co llu v iu m w as form ed at the fo o t o f the n iche (F ig. 2). It form s num erous sw e llin g s, ramparts di

v id ed by trenches and d ep ression s. O rganic deposits fill up o n e o f the h oles w ithout the o u tflo w situated in the low er part o f the collu viu m . A peaty m ass is the m ain com ponent o f 2 m thick sedim ents (Fig. 6 .1). There are overturned trunks aged 2 0 2 0 ± 1 0 0 yrs BP (G d -10161) at the bottom part o f the an alysed d ep ression (M argielew sk i, 1994b). The date fix es the tim e o f the y o u n g est stage o f the C yrla land

slid e zo n e form ed by m ass m ovem en ts.

GAW ORZYNA LANDSLIDE

A t the v a lle y head o f the Jaw orzyna stream , on the w estern slo p e o f M ount G aw orzyna (963 m a .s.l.), an ob se- quent, pack-rotary lan d slid e w as form ed (F ig. 1.2). A dou- ble-ridge is its m ain elem en t (M argielew sk i, 1994a). Traces o f tw o landslide generations are v isib le. A n older generation gave a rectilinear set o f n ich es and a lo o sen ed rocky pack (d ou b le-rid ge) and a yo u n g er phase, during w h ich rejuvena

tion o f the m ain niche took p lace, a high escarp sy stem w as form ed. D uring the landslide rejuvenation, at the foot o f the set o f n ich es, a narrow, 1.2 m deep trench w as form ed and filled up w ith grey-b lu e and brow n, sandy silt covered w ith dark organic silt (Fig. 6 .2 ). Sam ples o f w o o d fragm ents (d e

tritus) from the base o f the d ep osits record an age o f 1580

± 1 3 0 yrs B P (K r-151). T he date approxim ately fix es the tim e o f rejuvenation o f th e G aw orzyna landslide (M argie

lew sk i, 1994a, b).

JESIONOW A LANDSLIDE

A set o f su c e ssiv e lan d slid es form ed by several m ass m o v em en t generations occu rs on one o f the southern side- ridges deviatin g from the m ain top, in the area o f the H ala Pisana (P isana A lm ) (M a rg ielew sk i, 1994b) (Fig. 1.3).

O lder stages o f the lan d slid e are related to the headward ero

sion o f the Ł om n ick a stream . Lateral erosion o f the stream

initiated the rift-trench situated in the low er part o f the land

slide. T he landslide represents a con seq u en tly-fissu re, pack- debris typ e in the upper part and a pack-rotary typ e in the low er, rejuvenated part. D uring on e o f the m ass m ovem en t stages, in the upper part o f landslide, a h o le related to sub

n ich e depression w as form ed (F ig. 3.1 ). A t present it is filled w ith 2 .8 m thick, organic sed im en ts (brow n organic silt w ith peaty m ass) (F ig. 6 .3 ) (M a rg ielew sk i, 1994b). W o o d sam  pled from trunks at the base o f this sed im en t w a s dated at 7 2 6 0 ± 1 1 0 yrs B P (G d -4 9 5 7 ).

D uring the fo llo w in g , you n ger m ass m o v em en t stage, a

Fig. 2. Sketch and schematic cross-section o f the Cyrla land

slide (see Fig. 1.1): / - niches, 2 - trenches, 3 - colluvial swells and tongues, 4-co llu v ia l steps, 5 - creeping, 6 - colluvial depres

sions without outflows, 7 - peat bogs with sampling sites, 8 - rock boulders, 9 - Magura sandstones (in the cross sections), 10 - mixed colluvial mass (in the cross-sections), 11 - buildings, 12 - road

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Fig. 3. Sketch and schematic cross-section o f the Jesionowa landslide (see Fig. 1.3). 1 - older stage o f mass movement, 2 - younger landslide. Another explanations see Fig. 2

Fig. 4. Sketch and schematic cross-section o f the Swiniarnia landslide (see Fig. 1.4). Explanations see Fig. 2

on the collu viu m form ed during one o f the rejuvenation stages (F ig. 6 .5 ). W ood sam pled from trunks found at the bottom part o f the sedim ents in this h o le w a s dated at 1970

± 7 0 yrs B P (G d -1 0 1 4 0 ). T his is the date o f landslide rejuve

nation (M argielew sk i, 1994b).

vast rift-trench w as form ed in the low er part o f the landslide zon e. A nother, sm aller h o le occurs in the trench (Fig. 3 .2).

The organic sedim ents are 2 m thick (m ain ly dark-brown silt w ith a p eaty m ass) (F ig. 6 .4 ). W ood fragm ents sam pled from trunks situated at the bottom part o f sedim ents, record an age o f 4 7 9 0 ± 9 0 yrs B P (K r-150 ) (M argielew ski, 19 94b).

B oth dates o f the set o f the Jesion ow a landslide reveal the tim in g o f landslide z o n e rejuvenation during particular m ass m o v em en t stages. The J esio n o w a landslide zon e is one o f the fe w in the Outer C arpathians, w here stages o f m ass m o v em en t su ccessio n have been dated (M argielew sk i, 1994c).

SW INIARNIA LANDSLIDE

O n th e southern slo p e o f the Hala Turbacz (Turbacz A im ) o ver Ł om n ica, a large (3 5 ha) - frontal, obsequent, pack-debris landslide w ith vast, sub-niche flattenings occurs (Fig. 1.4). T he landslide has a rectilinear n ich e 800 m long.

T he low er parts o f the lan d slid e w ere rejuvenated by the set o f n ich es (F ig. 4). O rganic sedim ents con sistin g o f a dark- brow n organic silt, peaty m ass, 1.8 m thick, fill up the h ole

W IERCH NAD KAM IENIEM LANDSLIDE

On the w estern slop e o f M ount W ierch nad K am ien iem (1 0 8 2 m a.s.l.), a pack-rotary, subsequent landslide is o b  served (Fig. 1.5). It w as initiated by the d ev elo p m en t o f the v a lley head and the v a lley o f the B arn ow sk i stream (M ar

g ielew sk i, 1992, 1997). R ift-trenches are the m ain elem ents o f this landslide. Sm all m ass m o v em en t form s w ere gener

ated in peripheric parts o f the lan d slid e during the rejuvena

tion period. In the collu viu m o f one o f th ese form s a depres

sion w ithout o u tflo w w as form ed. O rganic sed im en ts (peaty m ass, dark organic silt) 1.6 m thick fill up the h o le (F ig. 6.6).

W ood sam pled from su b fossil trunks at the base o f the se d i

m ents w as dated at 7 70 ± 1 0 0 yrs B P (G d -6 8 1 7 ). The date fix es the rejuvenation tim e o f the N o r th -W e st zo n e o f the W ierch nad K am ien iem landslide (M a rg ielew sk i, 1994b).

LANDSLIDES IN THE VALLEY HEAD OF THE W IERCHOM LA M ALA STREAM

There are three dated lan d slid e form s in the vast v a lley head o f the W ierchom la M ała stream (a tributary o f the Po- taśnia stream ). The v a lle y head w as strongly shaped by

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m ass m ovem en ts. T h ese three landslides w ere form ed in the contact z o n e b etw een th ick-bedded sandstones o f the M a

gura Form ation and fly sc h d ep osits o f the Z arzecze Form a

tion (F ig. 1 .6 -8 ).

Wierchomla 1 Landslide

T he w id e landslide zo n e shaped b y the d evelop m en t o f the v a lley head o f the W ierchom la M ala stream cam e into bein g on the southern slo p e o f M ount L em barczek (Fig.

1.6). It is a consequent, pack-debris landslide extending from the top part o f the m ountain to the v a lley floor. It has a relatively lo w n ich e and a vast, step-shaped collu viu m (Fig.

5 .1). The im m en se d epression in the sub-niche zon e w as form ed during the m ain stage o f m ass m ovem ents. Pres

en tly, organic sed im en ts (dark-brow n organic silt and peaty m ass) fill up the h o le (F ig . 6 .7 ). W ood fragm ents sam pled from trunks stuck in the d ep osits g iv e an age o f 5 0 9 0 ± 9 0 yrs B P (K r-148). T he date g iv e s the age o f the m ain stage o f m ass m o v em en ts form ing th e landslide.

A seco n d landslide, situated eastwards, low er dow n than the on e described a b o v e, is also related to the v a lley head o f the W ierchom la M ała stream (Fig. 1.7). It is c o n se  quent, pack-debris form and has a rectilinear, high niche w ith vast flattering at its fo o t, w h ich is b lock ed b y a collu - vial rampart (Fig. 5.2). O rganic d eposits (dark organic silt), 1.2 m thick, fill up the h o le on the flattening. The depression w as form ed during the m ain m ass m ovem en t stage (Fig.

6 .8 ). W ood fragm ents sam p led from su b fo ssil trunks, w hich are covered w ith sed im en ts, w ere dated at 2 9 1 0 ± 9 0 yrs BP (K r-149). T his date g iv e s the age o f the m ain stage o f m ass m ovem en ts form ing the W ierchom la 2 landslide.

A n im m en se (35 ha) co m p lex landslide form cam e into being in the eastern part o f the v a lley head o f the W ier

ch om la M ała stream. It is a subsequent, pack-rotary form in the upper part and the pack-debris form in the low er part (F ig. 1.8). It exten d s from the sub-top zon e dow n to the v a l

ley floor. A vast, am phitheatre-like n iche rejuvenated in the southern part and varied co llu v iu m at its fo o t are the main elem en ts o f the d escribed form . In the eastern and north

eastern zo n es, the niche is a fragm ent o f the v a lley head o f the W ierchom la M ała stream . It is relatively flat and high (15 m ). T h e collu viu m in the shape o f elon gated ramparts w as transported dow nw ards: the first o f the ramparts is pre

served in the sub-niche z o n e w h ile the seco n d - ab ove the ed ge line o f the ex istin g v a lle y , w here co llu v ia l sw e lls over

lapped (F ig. 5 .3). Four dep ression s w ithout ou tflow w ere form ed betw een the ramparts and peat sedim ents fill them (F igs. 5 .3 , 6 .9 - 1 0 ) . The upper, w ider d epressions are deeper (F igs. 5.3 A , 6 .9). W ood fragm ents sam pled from trunks bur

ied in o n e o f the upper h o le s y ie ld an age o f 2 1 2 0 ± 1 2 0 yrs B P (G d -9 4 1 2 ). In the low er parts o f the landslide zo n e there are tw o sm all d epressions b lock ed w ith the collu vial ram

part (F ig. 5 .3 B ). Peat d ep osits, 1.5 m thick, fill them up (Fig.

6 .1 0 ). The b egin n in g o f sedim entation is dated at 2 0 8 0 ± 7 0 yrs B P (G d -1 1 7 6 ). The obtained dates describe the main stage o f landslide g en esis in the head v a lle y o f the W ier-

Fig. 5. Sketch and schematic cross-sections o f the landslides within the valley head o f the Wierchomla Mata stream: 1-3 - dated landslides (see Fig. 1.6-8), A -B - stages o f landslide Wierchomla Mata 3 development. Another explanations see Fig. 2

chom la M ała stream; they also sh o w the relationship o f both depressions w ithout ou tflo w to a sin g le ep iso d e o f m ass m ovem ents.

SEDIMENTS FILLING UP THE LANDSLIDE DEPRESSIONS

In the past, all the d epressions occurring in the analysed landslides w ere active, tub-type d ew p onds characterized by the differentiated bathym etry (Fig. 6) (N o w a ln ick i, 1976;

M argielew sk i, 1996). Part o f th em occur w ith in the sub

n iche depressions (G aw orzyna, J esio n o w a , W ierchom la 1,

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2 ), other ponds fill in tercollu vial h o llo w s (C yrla, W ier- ch om la 3 A , 3 B , W ierch nad K am ien iem , Sw in iam ia).

SECTION OF SEDIMENTS

T he seq u en ce o f sed im en ts w a s described on the base o f the core an alysis. T he sam p les o f deposits w ere taken b y a b ox borer. Sedim ents fillin g the depressions occur in a char

acteristic su ccessio n (F ig. 6). G rey-blue and b lu e-y ello w ish sandy c la y w ith fragm ents o f disintegrated sandstones form the bottom o f the organic d ep osits. T h ese are overlain b y the th ick est seq u en ce o f the peat sedim ents (peaty m ass). They are represented by peats (fen s typ e) w ith considerable am ount o f w o o d detritus and a h om ogen ou s, sp on gy, brow n, so m etim es san d y peaty m ass w ith organic silt. Intercalations o f w o o d peat and rare fragm ents o f sandstones are also pre

sent (F ig. 6). Dark brow n and dark grey, je lly like silt usu

ally occu rs at the top.

M ATERIAL USED FOR RADIOCARBON ANALYSIS

A t the bottom o f the sed im en ts in practically all depres

sio n s (e x c e p t the G aw orzyn a landslide) w ithin the o f peats or less frequently in the cla y s, tree trunks have been found.

T h ey probably fell d ow n to the depressions w h ile the land

slid es w ere form ed and forests overgroving the slop e w ere cut off. A sim ilar p h en om en on o f trunk accum ulation in the co llu v ia l depression w as ob served w hen the contem porary P olom a landslide in the B ieszcz a d y M ts form ed (M argie

lew sk i, 1991). The trunks w ere then covered w ith organic sed im en ts. Trunk d ep o sitio n and m ass m ovem en ts took p lace at the sam e tim e. T herefore, the radiocarbon m ethod o f w o o d dating a llo w to fix p recisely the tim e o f landslide form ing. In the case o f the Jaw orzyna landslides the w o o d sam ples for 14C datings w ere pick ed up from the trunks c o v  ered w ith sedim ents. O n ly the age o f the G aw orzyna land

slid e w as obtained on the basis o f w o o d detritus from the bottom o f d eposits, b eca u se the siz e o f the depression w as too sm all to accum ulate any trunk there (F ig. 1.2). W ood de

tritus (w o o d charf) dating is less precise, but nevertheless al

lo w s to approxim ate the tim e o f lanslide form ation.

S in g le radiocarbon datings m ade in organic deposits fillin g up the d ep ression s o f the landslides in the Jaw orzyna K rynicka R ange do not a llo w an estim ation o f their sed i

m entation rate. The m ean annual increase o f analogous peat sed im en ts fillin g up the landslide depression at S zy m b a rk - K am ionka (G il e t a l., 1 9 7 4 ) am ounted to approxim ately 0.51 m m and the clim atic ch an ges in the H o lo cen e caused an increase or reduction in accum ulation rate (Żurek, 1986).

LANDSLIDES OF THE JAWORZYNA KRYNICKA RANGE AGAINST THE BACKGROUND OF MASS MOVEMENT

STAGES DISTINGUISHED IN THE CARPATHIANS

The in ten sification o f m ass m ovem en ts in the H o lo cen e w a s co n n ected w ith clim atic changes cau sin g increasing hu

m idity (G il e t a l . , 1974; Starkel, 1977; 1985, 1986, 1990;

R alsk a-Jasiew iczow a & Starkel, 1986, Pazdur e t a l., 1988).

D uring the d evelop m en t o f th e Carpathian r e lie f in the H o lo cen e cy c le , several hum id periods w ere distinguished.

T hese periods recorded the stages o f in ten se flu vial activity, increased rates o f organic accu m u lation , and in ten siv e m ass m ovem en t d evelop m en t (Starkel, 1985, 1986, 1990). H um id periods are related to the term ination o f th e V istulian (1 0 8 0 0 - 1 0 0 0 0 yrs B P ), the b egin n in g o f the clim atic opti

m um ( 8 5 0 0 - 8 0 0 0 yrs B P ), the m id d le part o f the A tlantic Phase ( 6 5 0 0 - 6 0 0 0 yrs B P ), the b egin n in g o f the Subboreal Phase (5 0 0 0 —4 4 0 0 yrs B P ) (Starkel, 1986, 1 9 9 0 ), the term i

nation o f the Subboreal P hase (about 3 0 0 0 yrs B P ), the early Subatlantic P hase (2 3 0 0 - 1 8 0 0 yrs B P ) (Starkel, 1990), early M iddle A g e s (10-th to 11-th century A D ) (Starkel, 1986) and the term ination o f the L ittle Ice A g e ( 4 0 0 - 1 0 0 yrs B P) (Starkel, 1986, 1990) (F ig. 7). S ix stages o f m ass m o v em en t intensification in the Carpathians related to hum id phases w ere distinguished by Starkel (1 9 8 5 ), about 1 1 0 0 0 -1 0 0 0 0 , 8 4 0 0 -7 8 0 0 , 6 5 0 0 -6 2 0 0 , 5 0 0 0 ^ 7 0 0 , 2 4 0 0 - 2 2 0 0 , and 2 0 0 - 1 0 0 yrs ago (Fig. 7). T here is a go o d correlation b e

tw een the distin gu ish ed stages and the p eriod s o f in ten sive fluvial activity in the catchm ent o f the upper V istu la river during its d evelop m en t in the H o lo c e n e (K alick i, 1991; Krą- p iec, 1992; Starkel, 1994). A n increased freq u en cy o f flood s related to higher hum idity w ere recorded in the fo llo w in g intervals: the late Y ounger D ryas and the early Preboreal, 8 7 0 0 -7 7 0 0 , 6 6 0 0 -6 0 0 0 , 5 2 0 0 ^ 1 9 0 0 , 4 5 0 0 - 4 3 5 0 , 3 3 0 0 - 2 8 5 0 , 2 3 5 0 - 1 6 5 0 yrs B P , 5-th to 6-th century A D , 10-th to

1 1-th century A D and since the 16-th century A D (Starkel, 1994) (Fig. 7).

A fe w hum id phases and related landslide phases have been docum ented and partly verified by radiocarbon datings from a dozen o f the Carpathian lan d slid es (G il e t a l., 1974;

A lexan d row icz, 1985a, 1993b). S.W . A lex a n d ro w icz, by u sing datings an alysis (particularly 14C ), d istin gu ish ed 5 phases (L 1 -L 5 ) o f m ass m o v em en t in ten sification (A le x a n  d row icz, 1993b ) (F ig. 7). P a lin o lo g ic a lly dated lan d slid es at D zia d o w e K ąty (Środoń, 1 9 5 2 ), on M ount Bryjarka near S zcza w n ica (P aw lik ow a, 196 5 ) and the landslide on the bank o ft h e Skaw a river v a lle y in W a d o w ice (its co llu v ia are presently covered w ith sed im en ts) (S o b o le w sk a e t a l., 1964) are con n ected w ith the d eglaciation phase o f term ination o f the last glaciation (1 1 0 0 0 - 1 0000 yrs B P ) - m ass m o v e  m ent phase L I. T he form ation o f so m e lan d slid es (dated by geom orp h ological m ethods) in the region s o f D ęb ica and W ieliczk a (Starkel, 1960), as w e ll as in the areas o f M ount P ilsko, L ip ow sk a and R om anka (Ziętara, 1964, 1968) w as also related to the ab ove m en tion ed period. A t the turn o f the B oreal Phase and at the very b eg in n in g o f the A tlan tic Phase (m ass m o v em en t phase L2), the lan d slid es at S zy m b a rk - K am ionka and on the slop e o f the P arkow a Góra h ill in K rynica w ere form ed. T h ese w ere dated b y th e radiocarbon m ethod at 8 2 1 0 ± 1 5 0 yrs BP (G il e t a l., 197 4 ) and 8 4 3 0 ± 9 0 yrs B P (A lex a n d ro w icz & A lex a n d ro w icz, 1992; A lex a n  d row icz, 1993 b). The age o f the landslide at H arcygrund near C zorsztyn w a s determ ined b y the radiom etric m ethod at 7 7 5 0 ± 1 3 0 yrs B P (A lex a n d ro w icz, 1984, 1993b). The m ain d evelop m en t stage o f the landslide situated on the northern slop e o f M ount B ab ia G óra is a lso co n n ected w ith

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89

Fig. 6. Sections o f organic deposits filling landslide depressions (generalized and simplified). / - dark organic silt with root remnants, 2 -3 - peat deposits: 2 - dark and brown organic silt (peaty silt) with peat mass, 3 - peat mass mixed with wood remnants, clay and sand, 4 - yellow and brown clay with sand and fragments o f sandstones, 5 - fragments o f clays, 6 - fragments o f sandstones, 7 - fragments o f tree trunks, 8 - placement o f samples for radiocarbon datings (age in yrs BP)

this p h ase (A lex a n d ro w icz, 1978). T he results o f palin ologi- cal an alysis prove that sed im en ts fillin g the landslide ponds are from the M iddle H o lo c e n e (Trela, 1929).

T he age o f the lan d slid e on M ount C ergow a in the B e s  kid N isk i M ts w as dated b y p alin ological m ethod as co in cid  ing w ith the term ination o f the A tlantic Phase (W ięck o w sk i

& S zczep an ek , 1963).

D uring the hum id p eriod o f the term ination o f the Sub- boreal P hase (m ass m o v em en t phase L 3), the landslide on the slo p e o f the Parkow a Góra in K rynica w as rejuvenated, as the date o f 2 6 9 0 ± 1 1 0 yrs B P indicates (A lex a n d ro w icz &

A lex a n d ro w icz, 1992; A lex a n d ro w icz, 1993b). A t the sam e tim e, the you n ger lan d slid e in the Skotnicki stream v a lley and a sm all landslide form at Św iątniki G ó m e w ere form ed.

The age o f the first is 3 1 7 0 ± 1 0 0 yrs BP (A lexan d row icz, 1993b) and the secon d on e is 2 9 0 0 ± 1 1 0 yrs BP (A lexan d ro

w ic z , 1993a). The lan d slid e on the northern slo p e o f M ount

P alenica (G ubałów ka F o o th ills), p a lin o lo g ic a lly dated, is re

lated to the term ination o f the Subboreal P hase (Harmata, 1969). T he co n secu tiv e dates gain ed from the landslides in

dicate m ass m ovem en t in ten sification in the L ittle Ice A ge.

The first period o f this in ten sification (L 4) occured in the M iddle A g es. T he landslide in the B ia ły stream v a lle y near K rościenko dated at 535 ± 3 0 yrs B P (A lex a n d ro w icz, 1987, 1993b) and the older one in the S c ig o c k i stream v a lle y near K rościenko aged 6 4 0 ± 5 0 yrs B P are con n ected w ith this phase (A lex a n d ro w icz, 1986, 1993b ). D uring th e secon d phase (L 5) co n n ected w ith the term ination o f the Little Ice A g e (17-th to 19-th centuries), the lan d slid e in P o d o lik near P iw n iczn a (0 ± 1 5 0 yrs B P) (A lex a n d ro w icz, 1985a), the landslide in the K ozłeck i stream v a lle y (1 4 0 ± 5 0 yrs B P), and the younger o f the landslides in the S c ig o c k i stream v a l

ley (2 5 0 ± 4 0 yrs B P ) w ere form ed (A lex a n d ro w icz, 1986, 1993b). In 1813, as a result o f torrential rains, the landslide

12 — Annales..

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F ig . 7. D a ted la n d slid es o f th e J a w o rzy n a K ry n ick a R ange and their link w ith m ass m o v e m e n t sta g e s in th e C arpathians (alter Starkel, 1985. 1 9 8 6 , 1990: A le x a n d r o w ic z , 1 9 9 3 b ). / - m ain hum id p h a ses (after Starkel, 1986, 19 9 0 ), 2 - la n d slid e p h a ses in the C arpathians (after Starkel. 19 8 5 ), 3 - m ain p h a ses o f th e h igher flo o d freq u en cy in th e U pper V istu la B a sin (after S tarkel, 1994)

on the K icarz hill near P iw n iczn a, w as form ed. The c o llu  vium dam m ed up the Poprad river and a barrier lake w as created (N o w a ln ick i, 1971, 1976).

The tim e o f form ation or rejuvenation o f the dated land

slid es o f the Jaw orzyna K rynicka R ange correlates w ith hu

m id periods, w hen in ten sification o f m ass m ovem en ts w as recorded (Starkel, 1985, 1986, 1990) and w ith m ass m o v e  m ent phases distin gu ish ed on the basis o f the dated Carpa

thian landslides (A lex a n d ro w icz, 1993b) (Fig. 7). The older o f t h e landslides in the set o f t h e Jesion ow a landslide (F igs.

1.3, 3 .1 ) is con n ected w ith late Boreal and early A tlantic Phases o f m ass m ovem en ts Stage L2 (A lexan d row icz, 1993b) (F ig. 7). The you n ger landslide in the set o f the Je

sio n o w a landslide (F igs. 1.3, 3 .2 ) and the old est one in the v a lley head o f the W ierchom la M ała stream (W ierchom la 1 ) (F igs. 1.6, 5.1) w ere form ed during the period o f m ass m ovem en t in ten sification related to the beginning o f the Subboreal P hase (Starkel, 1985) (Fig. 7). T hese landslides are w ell based in the d istin gu ish ed hum id phase. The secon d o f the lan d slid es at W ierchom la M ała (W ierchom la 2) dated at 2 9 1 0 ± 9 0 yrs B P (F igs. 1.7, 5 .2 ) p recisely co in cid es w ith the hum id period in the H o lo cen e about 30 0 0 yrs BP (Starkel, 1990) and is p laced in m ass m ovem en t stage L3 (3 3 0 0 - 2 5 0 0 yrs B P) (A lex a n d ro w icz, 1993b) (Fig. 7). F ive radiocarbon datings from the landslides o f the Jaw orzyna

K rynicka R ange g iv e go o d d ocum entation o f the hum id phase distinguished at the b egin n in g o f the Subatlantic Phase (Starkel, 1990) in the interval o f 2 3 0 0 - 1 8 0 0 yrs BP (Fig. 7). A t that tim e, the y o u n g est landslide in the v a lley head o ft h e W ierchom la M ała stream (W ierch om la 3) (Figs.

1.8, 5 .3), the C yrla landslide near R ytro (F igs. 1.1, 2 ), the S w in iam ia landslide (F igs. 1.4, 4 ) and the G aw orzyn a land

slid e (F ig. 1.2) w ere form ed. T h e first o f the ab ove m en  tioned landslides has tw o syn ch ron ou s radiocarbon datings (F ig. 5.3, A - B ) . T he y o u n g est o f the dated lan d slid es in the Jaw orzyna K rynicka R ange (the W ierch nad K am ien iem landslide) (Fig. 1.5) is con n ected w ith early M iddle A g es phase o f hum idity and co in cid es w ith radiom etrically distin

g u ished m ass m o v em en t stage L4 corresponding to the older ep isod e o f the Little Ice A g e (A lex a n d ro w icz, 1993b ) (Fig.

7).

CONCLUSIONS

Intensification o f m ass m o v em en ts during the hum id period during early Subatlantic P h ase in the tim e interval o f 2 3 0 0 -1 8 0 0 yrs BP (Starkel, 1990) is w e ll based on fiv e dat

ings o f landslides in the Jaw orzyna K rynicka R ange. This allow to state that the landslide phase p rev io u sly dated at

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91

2 4 0 0 - 2 2 0 0 yrs BP (Starkel, 1985) w as o f longer duration:

this lon ger period v ery w e ll co in cid es w ith phase ( 2 3 5 0 - 1 6 5 0 yrs B P) o f t h e high flo o d frequency in the upper V istu la basin (Starkel, 19 9 4 ) (Fig. 7). The fo llo w in g tw o datings confirm the occu ren ce o f a landslide phase distin

g u ished at the b egin n in g o f the Subboreal Phase ( 5 0 0 0 - 4 7 0 0 yrs B P) (Starkel, 1985) (F ig. 7). T h ese landslide phases h ave not been d ocum ented up to n ow by the radio

carbon m ethod (A lex a n d ro w icz, 1993b). The rem aining three datings w id en the d ocum entation o f the landslide peri

ods d istin gu ish ed at early A tlan tic Phase, at the term ination o f the Subboreal Phase and in the early M iddle A g e s (Star

kel, 1985, 1986; A lex a n d ro w icz, 1993b) (Fig. 7).

Acknowledgem ents

I wish to express my gratitude to Prof. Stefan W. Alexan

drowicz for constructive comments on the paper. I would like to thank MSc. Jan Urban for help with field work and Dr Marek Krąpiec for help with radiocarbon datings.

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Streszczen ie

DATOW ANE OSUW ISKA PASMA JAW ORZYNY KRYNICKIEJ (KARPATY ZEW NĘTRZNE) I ICH

ZW IĄZEK Z FAZAM I KLIMATYCZNYMI HOLOCENU

W ło d z im ie r z M a r g ie le w s k i

Procesy osuwiskowe odgrywały dominującą rolę w transfor

macji rzeźby Karpat fliszowych, zaś ich szczególna intensyfikacja była wiązana z fazami wilgotnymi holocenu (Starkel, 1985). Sto

sunkowo niewielka ilość datowań osuwisk karpackich, wykona

nych dotychczas z użyciem metody radiowęglowej, palinologicz- nej. czy malakologicznej, utrudnia pełne udokumentowanie zwią

zku ruchów masowych z wydzielanymi fazami. Badania przepro

wadzone w obrębie form osuwiskowych pasma Jaworzyny Kry

nickiej, pozw oliły na znaczne poszerzenie i uzupełnienie rejestru osuwisk datowanych radiowęglowo.

Pasmo Jaworzyny Krynickiej będące wschodnim członem Beskidu Sądeckiego, położone jest pomiędzy dolinami Kamienicy Nawojowskiej i Popradu. Geologicznie znajduje się ono w strefie występowania dwóch podjednostek tektoniczno-facjalnych plasz- czowiny magurskiej: sądeckiej (bystrzyckiej) i nasuniętej na nią od południa podjednostki krynickiej. Główny grzbiet pasma wzno

szący się 10 0 0 m.n.p.m., został ukształtowany w obrębie utworów podjednostki krynickiej, reprezentowanych tu głównie przez gru- boławicowe piaskowce ogniwa piaskowca z Piwnicznej formacji magurskiej oraz drobnoiytmiczny flisz formacji z Zarzecza (Bir

kenmajer & Oszczypko, 1989) (Fig. I). Rzeźba pasma jest silnie przekształcana licznymi osuwiskami strukturalnymi inicjowanymi głównie erozją rzeczną, zaś rozwojowi tych form sprzyja silna ani

zotropia tektoniczna oraz zróżnicowanie litologiczne masywu piskowcowego (Margielewski, 1997). Wśród licznych osuwisk pasma często tworzących zgrupowania, znajduje się osiem form posiadających zagłębienia (podniszowe lub interkoluwialne), współcześnie wypełnione osadami organicznymi (ciemne i ciem

nobrunatne mułki organiczne i torfy) (Fig. 1). Występujące w spą

gowych partiach tych osadów pnie drzew, zostały powalone i zrzucone do zagłębień w czasie powstawania osuwisk (Fig. 6). Da

towanie metodą radiowęglową 4C materiału pobranego z tych pni w trakcie wierceń, umożliwiło stosunkowo precyzyjne określenie czasu powstania lub odmłodzenia analizowanych form osuwisko

wych. W wyniku analizy radiometrycznej, osuwisko Cyrla nad Rytrem datowano na 2020 ±100 lat BP (Fig. 1.1,2), osuwisko Ga- worzyna zostało odmłodzone 1580 ±130 lat BP (Fig. 1.2) (w tym przypadku datowano jedynie detrytus drzewny pobrany ze spągo

wych partii osadów zagłębienia podniszowego), starsza faza osu

wiska Jesionowa (Figs. 1.3, 3) była formowana 7260 ±110 lat BP, zaś młodszy etap rozwoju tego osuwiska 4790 ±90 lat BP. Fazę odmłodzenia osuwiska Swiniarnia nad Łomnicą datowano na

1970 ±70 lat BP (Fig. 1.4, 4), zaś najmłodszy etap rozwoju osu

wiska Wierch nad Kamieniem na 770 ±100 lat BP (Fig. 1.5). Osu

wisko Wierchomla 1 powtało 5090 ±90 lat BP (Figs 1.6, 5.1), zaś pobliskie osuwisko Wierchomla 2, zostało utworzone 2910 ±90 lat BP (Figs. 1.7, 5.2). Osuwisko Wierchomla 3 (Fig. I. 8) posiada 2 datowania: z górnego zagłębienia otrzymano datę 2 1 2 0± 1 2 0 lat BP (Fig 5.3A), zaś powstanie zagłębienia dolnego datowano na 2080 ±70 lat BP (Fig. 5.3B).

Czas powstania lub odmłodzenia tych osuwisk, jest zgodny zarówno z okresami holoceńskich zw ilgoceń (Starkel, 1986, 1990) i związanymi z nimi fazami osuwiskowymi (Starkel, 1985), jak i z okresami intensyfikacji ruchów masowych, wydzielanymi w opar

ciu o analizę radiowęglowych datowań osuwisk karpackich (Ale

xandrowicz, 1993b) (Fig. 7). Intensyfikacja ruchów masowych w fazie zwilgocenia we wczesnym subatłantyku, jest w obrębie osu

wisk pasma Jaworzyny dobrze udokumentowana pięcioma dato- waniami (osuwiska: Gaworzyna, Swiniarnia, Cyrla, dwie daty osuwiska Wierchomla 3) mieszczącymi się w przedziale 2120—

1580 łat BP. Datowania te wskazują, że faza osuwiskowa wydzie

lana w interwale 2400-2200 lat BP (Starkel 1985) może być dłuż

sza, gdyż okres ten jest zgodny zarówno z zasięgiem czasowym wczesno-subatlantyckiego zwilgocenia (2300-1800 lat BP - por.

Starkel, 1990), jak i z fazą wzmożonej aktywności fluwialnej gór

nej Wisły datowaną na 2360-1650 lat BP (Starkel, 1994) (Fig. 7).

Ponadto dwie daty (młodsza faza osuwiska Jesionowa i osuwisko Wierchomla 1) dokumentują fazę osuwiskową o interwale 5 0 0 0 - 4700 lat BP, wiązaną ze zwilgoceniem na początku subboreału (Starkel, 1985, 1986) (Fig. 7). Obydwie fazy osuwiskowe nie były dotychczas udokumentowane radiowęglowo (Alexandrowicz, 1993b) (Fig. 7). Pozostałe trzy datowania poszerzają dokumenta

cję faz osuwiskowych wydzielanych we wczesnym okresie atlan

tyckim (starsza faza osuwiska Jesionowa), w schyłkowej fazie subboreału (Wierchomla 2) oraz we wczesnej fazie malej epoki lo

dowej (Wierch nad Kamieniem) (Starkel, 1985; Alexandrowicz, 1993b) (Fig. 7).