Foraminiferal paleoecology and biostratigraphy in the ...

N. Jb. Geol. Paläont. Abh.

217 (2)

267-288

Stuttgart, August 2000

Foraminiferal paleoecology and biostratigraphy in the pre- and post-evaporitic Late Miocene (Messinian) of the Lorca Basin, SE Spain Jens St effahn and Dieter Michalzik, Bochum With 5 figures

STEFFAl-IN, J. & MI CII ALZ1K, D. (2000): Foraminiferal paleoeeology and biost rati g raphy in the pre- and poslevaporitie Laie Miocene (Messinian) of thc Lorca Bas in, SE Spain. - N. Jb. Geol. Paläonl. Abh. , 2 17: 267- 288; Stuttgarl.

Abstract: Thc di stribution patterns of foraminifera have been analyzed within th e la test TorlOnian to Messinian Serrata section of the Lorea Basin. The depos its are assigncd to the pre-evaporiti e to post-evaporiti e interval of the so-called Messinian sa linity erisis. Dist ribulion patterns indicate an overall regressive trend for thc preevaporitic part of th e Serrata se 150 flm size fraction with a microsplitter. Referring to LOH MANN (1978) the sampie residue < 150

).lm was not examined quantitatively due to an endangered influence of small exhumed or drifted specimens . The cOllnting da ta set was used for bio-

stratigraphie determination and for calculation of diversity and distribution patterns.

Biostratigraphy The late Miocene foraminiferal biostratigraphic concepts for the Mediterranean area are recently based on distribution patterns of keeled and coiling ratio uf non-keeled globorotaliids (SIERRO 1985, S,ERRO et al. 1993, KRIJGSMAN et al. 1995, 1997). It must be adm itted here, that specimens of

this family are rather rare in the Serrata section. Nevertheless, at least five bioevents sensll S,ERRO et al. (1993) respectively KRIJGSMAN et al. (1995, 1997) have been ascertained - w ith so me reservation - for the Serrata section in this work (Fig. 4). The concept of S,ERRO et al. (1993) regarding:

(I) The sudden disappearance of dextrally coiled, keeled menardiform globorotaliid Globorolalia menardii gr. I (PF-Event I, in the Upper Tortonian). (2) the replacement of dextrally coiled, keeled menardiform globorotaliidl Globorolalia mellardii gr. I by s ini strally coiled, keeled menardiform globorotaliid l Globorolalia mellardii gr. 11 after an interval in which keeled globorotaliids are reduced or absent (PF -Event 2, in the uppermost Tortonian). (3) One of three coiling direction changes or unk eeled Globorolalia scilllia s.1. (P F - E ve n t - A, at 01· elose to the TI M boundary). (4) the replacement of the lalter by keeled reniform chambered globorotaliid / Globorotalia mioillmida gr. (P F - E yen t 3, at the Tortonian l Messinian boundary). (5) the coiling direction change from dominantly sinistra l to dextral of Neogloboquadrina acostael1sis after Cf. miolumida gr. becoming the dominant keeled globorotaliid grollp (P F - E yen t 4, clearly in the Messini an). and (6) abrupt disappearance of the GI. mioillmida gr. (PE-Event 5, Upper Messinian).

Foraminiferal paleoecology and biostratigraphy in the pre- and post-evaporitic

275

is widely accepled and was recenlly adapted and supplemented by KRIJGSMAN et al. (1995, 1997) 10 cyclostratigraphy and an improved magnetostratigraphy. AdditionaJly the renewed influx ofthe Gf. miofllmida /co llomiozea-plexus

after a short period of disappearance (planklon even t 7 of KRIJGSMAN et al. 1997) and the FO datum in the uppermost Messinian of CI. nico/ae (planklon event 8 ofKRIJGSMAN el al. 1997) are recenll y used as further opportunities for high-resolution stratigraphie alld eorrelative approach es in the Messinian.

AI La Senala we clearly figured oul PF-Evenl s A , 3,4 and - wilh some reservation P F - E ve n I 5 of SIERRO et al. (1993). PI a n k t on eve n t 6 (equ ivalent to I'F-Event 3 of SIERRO et al. 1993) and wilh some reservation plankto n evenl 7 but eonsistently plankton event 8 of KRIJGSMAN el al. ( 1997) are distinclly present as weil (Fig. 4). In the lowermost part of the seetion at La Serrata Globorotalia menardii gr. 11 is quitc abundant, whereas Globorolalia menardii gr. I is totally absent.

The first is predominantly dextrally coiled and regarded by SIERRO et al. ( 1993) as sim ilar to C/oborolalia lIIencm/ii form 5 of TJALSMA ( 1971) and ZACHAR IASSE ( 1975). It resembles mainly the Iraditional species of C/oborOI(IIio culrra ta and less abundant GI. lIIerolllmida and GI. plesiotumida. Because GI. meJ1ardii gr. I is absent and GI. menordii gr. 11 is coml11only

presenl we - according 10 SIERRO el al. (1993) - presume a latesl Tortonian age (after Ihe PF-Evenl 2) for the basa l part oflhe sampled scction (Fig. 4). Thi s assigll3tion is also confirmcd by the co-occurrence of GI. surerae alld Neogloboquadrillo cr. dU/ertrei whieh have been found in th is lowermost

part of Ihe seclion and should first occur jusl be fore the TIM boundary (IACCAR INO 1985). At + 33 m above Ihe base of the seclion CI. lIIel/ardii gr. 11 is replaced by the preferentially left coiled keeled CI. lIIiollllllida gr. sensu SIERRO, et al. (1993) respeclive ly CI. cOl/olllinzea gr. sensu ZACII ARIA SSE (1979); Ihe two species are recently regarded as ecophenotypes and will be named here as the CI. miOlumida/col/ollliozea plexus. In this lower part al La Serrata (from + 33 m) this group resembles mainly the flat morphotypes traditionally named GI. miolumida and Globorotalia dalii anel less abundant conical form s like Gf. cOl1omiozea allel GlobOlvtalia lIledilerranea which appear

more frequ cnt ly in thc upper part of the section (Fig. 4). According to SIERRO et al. (1993) and KRIJGSMAN el al. ( 1997) this replacement (PF-Evenl 3 OfSI ERRO et al. 1993) and the initial dominance ofthe flat morphotypes is indicative for the TIM boundary in the Mediterranean. IACCAR INO ( 1985) already defines the first occurrence of CI. lIIiollllllida at or elose to the base of th e traditional Mcssin ian Cf. cOl1omiozea Zone. Aelditionally some m

below this replacement PF-Event 3 al La Serrata specimens ofthe unkeeled

276

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277

Cloboralalia scillila gr. change from dominantly s inistral to dextral for a short tim e which according to SIERRO et al. (1993) also occurs immediately prior to the TIM boundary in the Betic Gateway (their PF-Event A). KRIJ GSMAN et al. (1997) describe a coiling direction change in the CI. scilllia gr. to dominantly dextral at or close to the above mentioned keeled globorotaliid replacement event (plankton event 6/ PF-Event 3 of Sierro et al. 1993) for the whole Mediterranean. In the following at La Serrata, a non-distinctive zone is represe nted by a for the Late Messinian Mediterranean characteristic (e.g. IAccA RINo & SALVATORINI 1982, IACCARINO 1985) - Kümmerfauna. This foraminiferal assemblage with few and small specimens begins just a few meters (al + 104 m) below the Gypsum Member. Nevertheless, one charaeteristic element of IACCAR INO & SALVATORINI'S ( 1982) traditional "Non-distinetive

Zone", a significant coiling direction change of Neogloboquadrina acos/aensis could not be observed in this uppermost part of the pre-evaporitic Varied Member (Fig. 4). This coiling direetion change not related to Cloboralalia is defined by the first common oeeurrenee of dextrally eoiled neogloboquadrinids (PF-Event 4 of SIERRO et al., 1993) after the CI. lIIioIlIlIIida/conollliozea plexus beeomes the dominant keeled globorotaliid

group which is also known from time equivalent sections in the central and eastern Mediterranean (e.g. KRIJGSMAN et al. 1997, 1999). In the Serrata section we found this coiling direction change of Neoglobaqlladrina acoSlaensi.\" to preferentially dextral not until the base of the post-evaporitie succession even CARUSO et al. (1998) describe a substantial number of dextrally coiled neogloboquadrinids from some m bclow the gypsum at La Serrata, but we have to keep in mi nd that neogloboquadrinids display several

short time changes in their coiling pattern during the Late Miocenc (e.g. SERRANO 1979, IACCAR INO 1985 , SIERRO et al. 1993). At La Serrata PF-Event 5 OfSIERRO et al. (1993) the disappearanee ofthe Gf. l1Iiotumida/collOl1liozea plexus immediately follows thc PF-Event 4 and

most presumably indieates an uppermost Messinian age for the basal postevaporitic part of the seclion, although IAccARINo (1985), MONTENAT et al. (1990), PEREZ-LoR ENTE et al. (1992), ORT; et al. (1993) in general define th e re-establishment of full marine conditions after the salinity crisis in the

Mediterranean area as al ready Pliocenc in age. Another PF-Event according 10 SIERRO el al. (1993) is defined as " .... Globoro/alia margaritae s. s. becomes a common taxon in the assemblages of keeled Cloboralalia". We could not observe this at La Serrata but in a neighboring section of the Lorea Basin at La Quinta we found Globoro/alia margaritae "forma medi/erranea" sen$lI SERRANO (1979) right arter

the PF-Events 4 and 5 (STEHAHN & MICHALZIK 2000). Because just two

specimens were found and the evolutionat'y lineage of GI. margari/ae and

278


their stratigraphieal range in the Mediterranean is eontrovcrsially diseussed (e.g. SERRANO 1979, SIERRO 1985, SIERRO et al. 1993) its traditionally indicative character for a Pliocene age is to regard with some reservation.

In eonc1usion, wc figured out that thc basa l part of tbc section, congruent witb tbe first diatomitic papersbales is uppermost Tortonian (afier PF-Event 2 of SIERRO et al. 1993) in age and tbat the TIM boundary (PF-Event 3 of SIERRO et al. 1993) at La Serrata can initially be situated in tbe lower tbird (around + 33m) of the section, even ROUCHY et al. ( 1998) located the TIM boundary furthcr in the foot wall deposits of the Serrata Formation (in the Hondo Marls) referring to a FO datum of CI. cOllollliozea. Furthermore in the Lorca ßasin main evaporite precipitation seems to have occurred

not before the Late Messinian (after plankton event 8 of KRIJGSMAN et al. 1997) and the initial post-evaporitic repopulation took place most presumably still in the latest Messinian (eontemporarily or be lore PF-Events 4 and 5 of SIERRO et al. 1993). Plioeene marine sedi ment3l·y deposits at La Serrata are not proved but - with so me reservat ion - to presume for the upper-

most part oftbe seetion (STEFFAIIN & MICHALZIK 2000).

Paleoecology The biodynamic effects of the Messinian salinity crisis on the marine biota

in tbe Mediterranean have alrcady been deseribed by BENsoN (1976), BERGGREN & HAQ (1976), CtTA ( 1976), VAN DER ZWAAN & GUDJONSSON ( 1982) and more reeently by VAN DE POEL (1992) and FORTUI et al. (1995). The scenario of increasing sali nity ami restrietion ofwater circu lation due to periodic isolation and its effects on marine organisms may be considered for

tbe Lorea Basin as weil si nee it was part ofthe whole Mediterranean system. Species di vers ity, plankton distribution patterns and th e quantitative C0111position ofbenthic foraminifera faunas have been analyzed to reconstruct the paleoenvironmental history.

Planktonic foraminifera

Planktonic foraminiferal speeics dive rsity at La Serrata seet ion ranges from 2 to 23 speeies but displays no parti eular trend. 1t rather seems to reneet eyelie osei llations (Fig. 5). Plankton opportunists, mainly Clobigerina bulloides and secondary Globigerina quinqueloba are very abundant and dominate tbe paucispeeifie planktonie assemblages with max. frcquencies up to 90 pereen!. Tbey are deseribed as bigbly tolerant of unstable environmental conditions (VtNCENT & BERGER 198 1, SIERRO et al. 1999) and indieate rat her cool, nutriellt-rich waters and could serve as an illdication for reinforced oceanic water supply.


279

Surface to intermediate dwellers, as most spinose specimens, including

speeies of G/obigerilloides and some G/obigerinG respeetively Orbll/ino live in the upper part (0-100 m) of the water eo lumn (TOLDERLLJND & BE 1971, BE 1977). Frequent represe ntatives are G/obigerinoides blil/oides. G/obigerinoides ruber seigliei, Orbulina universa and Globigerina aperlura. In the pre-evaporitie unit of the La Serrata seetion deep dwelling taxa are less abundant than surfaee dwellers. Here deep dwellers eomprise most thiek wa lled speeies, ineluding mainly speeies of G/oborotalia. Even if a vertieal migration during the ontogeny of many speeies must be eonsidered, thiekwalled adult speeimens ean se rve as indieators for deep dwelling (BE 1977, V,NCENT & BERGER 1981). At the La Serrata seetion mainly menardiform G/oborotalia speeies form this key group. Deep dwellers are ra re in the pre-evaporitic successiol1 and distinctly decline upsection from maximum

frequeneies of 16 percent to total absence (Fig. 5). In summary it may be said that the planktonic assemblages of the pre-evaporiti e Varied Member indicate good living conditions concerning the surface and intermediate

dwellers for most of the time . On the other hand deep dwelling taxa periodieally suffered by moderate to finally bad living eo nditions.

Benthic foraminifera Benthic foraminiferal diversity at La Serrata varies between 4 and 18 species

with deelining tendeney upseetion (Fig. 5). Benthie foraminifera almost exelusively resemble hyaline taxa. Miliolids, textulariids and ostraeodes are very ra re at La Serrata. Important constituents of most assemblagcs are Hanzawa;a houeana and NOI/;oll padanum. On average these and a few olher nonionid species contribllte about 15 percent in average but do not show any significant trend. Hanzawaia is considered to represent "norma l" ve ntil ation

eonditions (SNYDER et al. 1988) and water depths of the (inner) shelf (MURRAY 1991). Other eommon taxa with varying eontribution (min. 3 to max. 18 percent) to the benthie assemblages are eibieidoids (main ly Cibicidoides jloridallo), gyroidinids (mainly Gyroidillo so/dclI/ii and Gyroidillo a/Ii/orlllis) and less abundant some eibie ids but their bathymetrie signifieanee is rather low (BERGGREN & HAQ 1976). On the other hand benthie foraminiferal "assemblages" at the La Serrata seetion reveal episodieally inereased frequeneies of - informally ealled " paleoeeologieal key groups": ( I) Bellthic foraminifera at La Serrata wh ich may be lIsed as cnviron l11cntal indicators are spccies of Lenliculina (L. ca/eOl; L. crassa) and Pul/eI/ja

blll/oides. They are attribuled to weil oxyge nated eonditions (SNYDER el al.

280


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281

1988) and outer shelfto bathya l "deep" water depth (M URRAY 1991). At La Serrata they selec ti ve ly occ ur wit h up to 50 percent of the benthic assemblages but are restricted only to the lowermost part (0 m to + 20 m) of the sect ion (Fig. 5). (2) The portion o f benthi c forms li ving in interm ediate water depth and potentially tol erating oxygen depleted environments episod iea ll y inereases upseetion. This key group includes costate and hi spid uvigerinids, species of BuliminG (main ly B. aClIleata and B. cf slIbaclImillala) , GlobobuliminCl and

Bolivil1(1. Their bathymetrie s ign ifieanee at generi c level is rather low, but

in general they indieate inner she lf to bathyal depths (M URR AY 199 1). ß ERNHARD ( 1986) descr ibed a domin anee of the genera Uvigeril1(1 an d Bolivina in Mioeene anoxie sed iment s of Ca lifornia. in addition, modern buliminid / globobuliminid-assoe iat ions are often described from low oxygen enviro nm ents (MILLE!< & LOHMANN 1982). This key g roup periodically oce urs with about 40 percent in the interval between + 10m to + 85 m in the La SeITata section (Fig. 5) . This may suggest th at the Varied Membe r was deposited partially under dysoxic condit ions. (3) Shallow wate r euryhaline specimens ineluding AlI/lI/ol1ia spp. (main ly A. beccarii and A. Plil/cla/o-granosa) and Eiphidilill/ crisplllI/ but a lso unkeeled Elphidium macel/um are known as the dominant taxa of reeent shallow

habitats wi th hi g hl y variable sa linity (MURRAY 1991). At La Serrata these forn1s ga in in ab undance upsection and dominate the benthie assemblages in the uppermost part ofthe pre-evapo riti c deposits ( Fig. 5). At + 99 m this key group provides al most 60 percent of the benthie assemb lage and is regarded as autocht honous. In summary, a di stinct eeologieal suecession ea n be inferred from the preeva poritie benthic fau na. It leads from normal ma rin e we il oxyge nated to periodically less ve ntil ated environment s. The benthic fauna I succession also indieates that wa ter dept h beeame shallowe r even if this shall ow ing was not strietly consistent. Restrietion of bottom circ ulation pattern s and elevated brine eOllcentration may thu s be consi dered even be fore the onsel of ma ssive

evaporite prec ipi tation. This is particularl y elue idated by the fact that so me m below the base of the Gyps um Member the fo ram iniferal fauna impover ishes. The so-ca li ed Kümmerfauna is represented by low abu ndanee and dwarfism ofjust a few bentl1ie and pl anktonic taxa. In the Mediterranean this feature is also illterpreted as a result of increascd brine eonccntra ti oll (c. g.

IACCAR INO 1985). As mentioned above, the gypsum deposit presents only few thin mari seams and thus does not co/lta in a eo nsiderab le fossil record. Some sm all planktonic foramin ifera have beeIl observed in thin scctions

but not ciassi fied. The autoch th onous or a lloe hthono us eha raeter of these specimclls remains unclear.

282

J. Steffahn and D. Michalzi k

In Ihe Laminated Pelite Member, j usl above the Gypsum Member, plankton species di vers ity rapidly reaches its pre-evaporitic level (Fig. 5). Plankton opportunisls, mainl y Globigerina bul/oides, are less abu ndanl than before the evaporation event.

ß e nthi c foraminifera revea l a hi g h diverse repopulalion in th e La minated Pelile Member. Almost immediate ly above Ihe gypsum benthic diversity exceeds its pre-evaporitic level wi th a ma ximum of 3 1 species (Fig. 5). Many specics that have not been found in the pre-cvaparitic succession no\\' occur far the first time, e.g. species of LagenCI, rissuril1a and Globocassidlllillo .

Others retu rn like species of Lenliculilla an d Pul/ellia but just with low abllndance. As in the Va ried M ember spccies of /-IC111zClI,vo;a, Cibicidoides, Gyroidil/a and ci bicids are C0l11111on constituent s of the benthic fauna. Fora-

minifera wilh di ag nostic significance for hi ghl y var iabl e salinity shallow water are rare in th e basal po st-cvaporiti c part of th e scction . A t La Serrata

the Ira nsition to bracki sh " Lago Ma re" facies is not evide nl until the upper part of Ihe post-evaporitic succession wh ich has been studi ed in details by Ihe a ulhors in a forthcoming paper (STEFFA II N & MI CHALZIK 2000).

Discussion and conclusions Paleogeograp hi ca l and sedimentological data indicale a se mi-enclosed basin eonfiguration for th e Lorea area dllring the L ate Mioeene in a rather

marginal position ofthe ßetic Stra it (M IG IALZIK 1997, RID ING et al. 1998). However, 1110re

01'

less continuoll s oceanic water slIpply was gllaranteed

Ihrough a system of interconnected basins at leasl be fore and after th c depositio n of eva porites. During Ihe ea rly Messinian periods of high nutrition ca used phylop lanktonic blooms and res ult ed in siliceo us biogenie sedime ntation of diatomitic papershaies (J URK SCII AT 1995, JURKSCHAT & FENN ER in press). A general shallowing upwa rd tre nd for this time interval can be deduced from the facies success ion (DITTE RT el al. 1993, MICHALZ IK 1997 , ROUCIIY et al. 1998) and is clearly supported by our paleoecological data.

The described succession of planklonie a nd benthic fo ra minifera l assemblages suggesl a periodic restrietion of waler c irc ul ati o n a nd the develop ment of a bottom water low ox ygen zone. The formation o f density slralificati on in Ihe water col umn o f a small basi n may be attri buted to a negati ve waler ba la nce (ß ET HOUX 1979, ANATI 1980) Ihal ca uses increasing sa linity and sinking of the de nse r sa line wate r (c. g. KE NETT 1982). However, a den sity stratification can also be relaled 10 hypopyc nal overfl ow due to increased inflllx o f meteorie wa ter. T hi s was eonsidered by JU RK SC HAT

( 1995) because of a substanti al number of freshwate r diatoms found in th e


283

uppermost parts of the Varied Member. A strengthened influence of fresh water is suggested by TABERNER et aJ. (1997) based on geochemical data from the Lorca and other Neogene basins. Apart from the uppermost interval ofthe pre-evaporitic sequence this supposed superficial intluence of meteoric water is not retlected in the microfossil record. On the other hand, a stratified water column with elevated sa linity of the bottom water is indicated by the above mentioned intercalation of thin gypsum layers "nd evaporitic limestone in the pre-evaporitic Varied Member. Temporary dysoxic bottom waters, as verified by fluctuations in benthic and "deep water" planktonic foraminifera and by the deposition ofdiatomitic paper shales can also be deduced from the preservation of organic matter. Up to 25 % of organic carbon have been determined in fresh material ("oil shale") from boreholes and old sulfur mines (PERMANYER et aJ. 1994, ßENALI et aJ. 1995) in the Varied Member. It may thus be concluded, that evcn bcfore the massive deposition of evaporites, circulation patterns became

periodically restricted in the Lorca ßasin rcsulting in water body stratification with oxygenated surface water and dysoxic bottom waters andlor

elevated salinity. Rcpeated returns to open circulation and repopulation can be seen at the mari-diatomite bed sca le. Recently HILGEN et aJ. (1995), KRIJGSMAN el aJ. (1995, 1997, 1999) and S,ERRO et aJ. (1999) have proved prccession induced insolation being respon siblc for cyclic patterns in Late Miocene sediment3I·y sllccessions in the Mediterranean. It is very likely that

5'h to 6'h order bed-to-bed cycies in the Lorca ßasin are also triggered by

these climatic changes. On the other hand a superimposed success ion of fauna I "restriction-recovery cycles" and therefore prcsumed

at least five

"regression-transgression para sequences" of 4 1h order may be inferred from

the foram ini feral record. These superimposed cycles can be correlated with sedimentary cycles from other marginal parts of the basin (WIWBEL & M,CHALZ,K 2000, STEFFAHN et aJ. 1999) and may thus represent basinwide relative sea-Ievel changcs or even an extrabasina l eustatic control.

A renewed marine tlooding of the Lorca ßasin, after deposition of evaporites can ciearly be ascertained as still Messinian in age and not Pliocene as suggesled for other areas of lhe Mediterranean (IACCARINO 1985, MONTENAT el aJ. 1990, PEREZ-LoRENTE et aJ. 1992, ORT; el aJ. 1993). RIDING el aJ. (1998) and SANCHEZ-ALMAZO et aJ. (1999) already proved a Mcssinian reflooding and recoloni zation for the Sorbas Basin representing a basin in

the ßelic Sl rail eiose to lhe present-day Mediterranean. For the Lorca ßasin a rapid diverse repopulation of planktonic and bcnthic foraminifera can be observed in the post-evaporitic rock sllccession, even the Lorca Basin is

considered as one of the distal basins in lhe ßelics. The rapid recolonization by benthic foraminifera which lack a planktonic larva l stage is conspicuoLis. Concerning the post-crisis faunas in the Medi-

284


terra nean Sea, WRIGHT ( 1976) pointed out, that some orga nisms may have sat out the sal inity crisis in so-ca lied Medi terra nea n rcfllg ia. In the case of the Lorea Basin it can be suggested, that neighboring basins of the Betic Strait, e. g. Vera or Mazarron more or less kept IIp thei r marine character and their connection to the Atlantie Ocean during the whole Messinian so that the post-evaporitic repopulation eould have started fro m here but this is still controversia lly discussed (e. g. FORTUIN et aL 1995).

Acknowledgements The authors would like to thank F. MAUTHE, R. FISCHER, G . BODE, M. HARTMANN and especially F. WROBEL (Univ. Hannover) and Th. JURKSOIAT (BGR) for sti mulating discussions on general problems and implications of this study of the Lorea Basin. Diseuss ions with J. FENNER (BGR) and remarks of M. B. ClTA (Un iv. Milano) on the manuseript also proved esse ntial and helpful. Many thanks are extendcd to H.-U. METZGE I~ (Univ. Hannover) and S. STÄGER (BGR) tor their teehnieal su pport. This investi gation was supported by grants (MI 353/2-1) from the Deutsche Forschungsgemeinsehaft (DFG).

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