I

Rom. J. Petl'Ology. 1994, 76, p. 67-76

PETROLOGY AND GEOCHEMISTRY OF THE EFFUSIVE ROCKS FROM THE OCEAN FLOOR BASALT COMPLEX IN THE MUREŞ ZONE

lIaralambie SAVU, Constanta UDRESCl', Vasilica NEACŞU, l\lihai lC1I11\1

Jnstitulul Gl'ologic al Homânici. Str. C'aransebe§ IU'. 1,783'1-1 Bucllre§li 32

Key wonb: na~alt~, Spilit('. ~Iaglllas. Tholeiitic eomposition . Magmatie diffcrentia-tioll. ~Ia.ior ('}Plllc·lIh . I\linol' eIel11cnls. l\llIrc'~ ZOlle. Apuseni I\lounlaills.

Ah:,;tract: Tlic occan Hool' },i1silllic (·ollll'k.\ (OI) [rom tii!:' Jnf'ga"lab prc',;

I

TI. S'AVU et al.

,:-: ... ?' )( x )( )( .. )( )( )( )( !+ ."" ... r:::~ )( )( xl \ x )( )( x/.

•••••••• :.' . " V " /':';' • ••••• /\ X x'v v'.~ )C"y,-+ . . .., -:-;'\!_l;C_'~ L y .~. V y':t

,,/~ /+ +', ,+ A

.··· I./Vyy,++:VYV/+ . .. "7. 1 ' ,.' ,.;. .'+ t' ~"'. ' ''' . 't I /v V V ,i+ ... ,"'vevu]oneş I

~4 L.:..:..:..:..: . '. \'.' ~ /"1. I! V V (+/ V V /+ ... . ~ /' /' I Il V V v'v V l +

"//'/ ,1 : /+ . . . . /'" /' ~ 1 1,1 y v V V V V:+

. .. ......." /' ' / / V V V V V '+ . . . e Bal'o -- / /" ./ -' V \"+ ., ..- ",,.,,.," ~+ '. '. • _ - ___ - ::: - --- ___ / ", ",-/./' V V V V V Y •• v. V '··,t ...- --- ..--..:-...--- / /",- /.--v Y Y V V V /'''~+;·+'.v V:+

,.,- --,,-,: .".....,., ..-".. /' / /,,,,,v " + + +: :+ .,,- ,...." ,., ."" /" /' / .... ~ .... - ...... , V V V \ V V " + + + ,/ v,' ,- ",.,.. ./ ,'-": + +.... /., # /+

,.. -- . .,.,., ,... ,/ .. /" + +"cJ V 'v V I \v V v't, + ~ ..... " V ,/ _~ .. _ ~ " ./ /' .... , + + ' , , "-t...." +

.,.,: ........ -< ,,"VI IV V Y V ~l ., V V y"y ):"+ I .. ~/ .... V ./+ + • ..,,, .. I " ..... ' + ,0 Bata ","Y ./+ J.eSaYlrsm V V ••• ~ •• , • y ...... + O 2 4Km

I '+:z: + +' " eS _ ..... + 'Y..--J·"--Mureş ",X./'·' vf ' + L.' _......L'_......I'

1 il-(. I "k'·I .. " Illitl> 01 II,,· o. IIsually ill pillo\\" lava [aries (1'1 1, I·'i!l,'" 1

I

PETROLOGY AND GEOCHEMrSTRY OF THE BASALT COMPLEX 69

in places chloritized, arc found among the basal t f1ows. They are usually present as small spheroidal or ovoidal separations which peel oIT concentrically. It is also worth noting tlle fact t.hat among the basalt. f10ws from the Căpâln a§- G lodgh ile§t i -Să 1 i§t.ioa l'a region , si tuated in the area to (,h(' soutll-east of the sheeted c1yke com-plex, intercalations of chemical precipilation ami detri-lai limestones with thiu Liassir quartzitic sands(,one bands occur, which indicates that this area was claseI' to the southern cont.inent. in t.he oceanic zone (Savu 1984 a; Savu et al., HJ88 b). Such depQsiLs elo not ex-' ist among Lhe basalt f10ws from the Baia Scale; on the other hand, therc occm slllall ahyssal red argillites de-void of jaspcrs, indicatillg an enea of Lhe lVlure§ Ocean of a much gre ater depth (Savll et al. , 1988 a).

The basalt lava flows consisL of rocks exhibit.ing interserial Lo subophitic structure sLlch as basalts , hyalobasalts, amygdaloidal hasalts and anamesites which are scldolll associatcd wiLh dolerite sills. TlIe rocks consist of plagioclase (A n 50- 60) laths, allgi(l', sometimes slightly titaniferous crystals, with which magneti Le and 1110re rarely pyri te are associated. be-sides variable amoullts of glas:>. 'l'he cryslallization order of minerals - t.he one specific for the tholei-it.ic basalts - is: plagioclase- c1inopyroxene- magnetite-pyrite. The spilit.ir. rocks are also frequcnt, in which plagioclase is an albite (AII 8- 10). whilc elinopyroxelw as well as the interstitial glass were chloritizecl.

In the basalt. complex gabbro bodies and smallJwri-dotite int.rllsions were emplaced, which were search"d on oLher occasions (Cioflica , 19G2; Savu , 196:2 a: J!)(i:! b; Savu eL al., 1970: SavlI et al., 1990 b). A,,; it 11:1:-already been showlI hy SavlI and Alldrei (19~l:3) , III' small gabbro bouies at C'ăzăne~ti and t.he larg!'r gal, broic boelies at Almi1.!iel anei Cuia§ as well as tlle Sllliili peridotite intrusion north -east. of Corbe~tj ar

iO lI. SA VU ei al.

Tahle - C'lwmical cOlllposition

No 1 2 3 4. 5 6 7 8 9 10 11 Si02 39.31 39.80 41.60 42..16 13.111 4:1.6:3 4:3.74 4 ·1.25 '1.5 .20 4.').20 '15.22 Ti02 O.JO 0.76 1.16 1.12 () 111 1 0·1 1.24 0.72 fJ.IIO 1.28 1.96 AI 2 0 3 13.59 15.36 I ·U~'l D.81 LH9 1 ').19 J:UJG 1·),91 U.(1) JUG 13.71

FeZ 03 5.49 5.09 (j.53 6.69 4.:35 6.19 6.~! .5.6 1 UD 'Ut3 5.65 feO 1.87 2.10 3.06 2.0!' .3. I !l .lA 7 2 .. 54 2 . 23 2 .G·1 3.8·1 7.2'2 Î\lnO 0.12 0.14. 0.16 O.Jl 0.16 0.13 0.13 0.105 0.16 0.16 (J.24

Î\lg0 05.55 5.28 6.805 5 .,-._1 6.% 7.26 5.5·1 (U8 5.51 5.76 6.1.3

CaO 16.24. 16.12 12.28 16 .11 14.40 10.!J8 12.63 13.26 12.89 \).00 8.84.

Na2 0 2.65 3.3.5 3.95 2.11 3.051\ 3.89 3.7Ci 2.83 3.50 4.41 2 -.) ./ -1(2 0 0.31 0..10 0. :!1 n.28 O.·U 0.15 0.10 0.22 0.76 0 .0.5 0.20 PzO

I

Pr~TRQLOGY ANI) GEOCHEMISTRY OF TIiE BASALT CQMPLFX '7 l

of the hasaltic rocks

12 13 14 15 16 17 18 45.70 4)).86 46.23 -16.30 46A3 16.1'1 1Ij .. 53

0.84 0.96 0.60 1.16 1.80 0.6,1 1.10 16.0'1 16.0] 15.35 14.59 14.10 11.95 16.56

3.87 4.21 1.65 3.93 5.94 5,26 4.56 4.69 4.80 4.82 5.06 5.90 3.23 5.75 0.36 0.24 0.14 0.16 0.26 0.11 0.19 9.74 7.16 9.7:3 7.18 5.54 7.28 6.99 7.93 8.85 6.80 9.69 7.89 11.46 10.79 2.15 3.54 3.41 3.62 3.98 1.63 2.49 1.40 1.59 0.48 O.I:.! 0.33 0.60 0.2.5 0.09 0.1 O 0.12 0.13 0.24 0.15 0.17 0.64 0.29 0.20 0.23 0.24 O.] 8 0.21 2.60 2.57 L'5·j 1.72 2.13 0.R9 0.77 4.71 3,26 6.30 G.08 4.73 6.68 3.31

100.76 99.4,1 100.37 99,97 99.51 99.50 99.99 70 57 100 57 .')2 185 95 28 :El 29 34 40 33 38

270 1;).5 220 155 % 410 2f10 200 200 160 230 460 150 370

32 2!) 32 J.l 30 18 3,\

20 18 20 22 ;12 16 27 J.G 2.1 1.4 l.8 3.8 1.2 3.4

19 20 21 22 16.70 ·16.91 17.02 17.03 1.20 1.60 0.92 0.88

14.04 15.71 14 .10 15.3G J.45 5.70 3.60 4.22 6,07 5.24 4.89 4.13 0.17 0.23 0.14 0.14 8.17 .5 .31 8.38 8.20

"tI.59 9.01 11.56 11.23 3.07 4.72 1.79 2.12 0.24 0.28 0,42 OAO 0.12 0.21 0.15 0.15 0.17 0.:13 0.25 0.24 2.59 1.2:3 1.68 1.78 2.64 3.03 5 .. 18 3.95

IOU.2.! 99.51 100.52 100.13 48 37 210 120 ·10 30 42 30

135 75 500 :j::lO

260 400 310 220 37 31 38 :14 24 29 27 19

2.9 .'3.6 2.0 1.6

I

V ppm

soo

400

72

100

1';'0

'00

No Si02 Ti02 AI20 3 Fe2 03 FeO MilO MgO CaO Na20 1(20 P20s S CO2 IhO Total Ni Ca Cr V Se Y Yb La Zr Ba Sr Pb Cu Ca ZII \;1,

L-.

23 47.08

0.92 ]3.24 5.04 3.33 0.18 7.00

12.00 3.32 0.60 0.11 0.23 3.03 3.93

100.01 75 40

250 260

42 26

2.9

I

PETROLOGY AND GEOCIIEMISTRY OF THE BASALT COMPLEX 73

Table( con tinued)

34 35 36 37 38 39 40 41 ~2 43 44 48.60 48.90 49.40 49.68 49.74 49.97 50.30 50.70 51.79 51.97 52.22

1.04 1.20 1.00 1.08 1.90 1.28 1.24 1.12 1.36 1.92 1.72 14.41 14.69 14.24 15.31 16.56 16.30 15.50 16.20 14.56 14.84 14.30

3.56 4.74 6.01 6.49 8.27 6.36 6.64 5.33 5.40 6.41 5.66 4.76 5.16 2.53 1.48 4.26 2.50 2.61 2.66 5.06 4.50 4.98 0.16 0.17 0.13 0.17 0.17 0.13 0.16 0.13 0.15 0.17 0.21 7.27 7.08 4.00 5.58 4.00 3.77 5.29 4.79 .'Ul6 3.01 4.81

12.29 8.93 12.20 7.53 2.25 5.20 7.03 7.61 8.04 5.04 4.52 3.64 4.14 4.69 4.00 5.36 5.15 4.94 4.24 3.04 6.20 3.89 0.36 0.16 0.25 0.93 2.74 3.40 1.27 0.82 0.37 0.95 0.07 0.13 0.15 0.15 0.15 0.27 0.29 0.24 0.22 0.29 0.22 0.24 0.30 0.24 0.33 0.16 0.28 0.22 0.16 0.15 0.33 0.28 0.21 1.62 0.76 2.31 4.71 0.96 1.46 0.30 2.0] 1.62 1.37 2.93 2.35 4.36 3.82 2.52 2.97 3.49 4.06 3.49 3.31 2.86 4.14

100.52 100.67 100.26 99.79 99.73 99.52 99.74 99.47 100 .38 99.74 99.90 70 32 63 2 38 50 34 110 52 33 14 27 25 19 ;{.5 25 26 17 30 42 :lO 16

250 18 250 1 55 140 17 240 110 50 4 175 180 230 30 340 180 230 180 :310 400 230

40 30 29 15 24 22 30 30 32 30 20 26 25 21 65 30 30 26 28 33 37 34

2,2 2.8 3.2 6.5 J.6 4.4 1.8 1.6 3.2 4.4 2.G

74

this conccntratioll reaches only exceptionally 6.20 % Na3 0. As already ShOWII, this Na20 acculllulation is due to both thc spilitizatioll through the reactiOll ofthe ba; lVil II I Il e oceanic wal er aud t he part ial dJlTerentialion of the Iholciilic magma. Tlw rocks with the greate»1 sodiulll eOllct'lIlralion hrlollg 1.0 IIIP latter eil.!'l'. TIlt'fart Ihat Illis i\a:!OCOnl"t' ll1ratl () 1l isdlH'10

7

6

5

4

3

2

1 I~ f,

PI a te

Margi n

Basalts

•

• • . .. -

••• • • • • .. : .. ••••• • •

• • •••• : ...

•

100 200 300

With in

Plate

Basa 1 ts

400 500 600 Ti/Y

II .. 1.1/' 1 il)" dlil~lil"l (",.,,,,"i"l( (» l'l'ill'(" anet

50000

Ti ppm

20000

10000

5000

2000

/ /

(

/

,.. .,-

/

I .-I '" '-_/

20 50

(

;'

./ /

\.

..... , \

\ \ \

100

,..-._._ ................. , \

\ \

\ ,

WITHI N

\ PLATE ARC \. LAVAS

LAVAS \ \

, , 200 seo 1000

Zr ppm

Il. S'AVU et al.

both phellomena is indicaled by the rocks shifting on tlte diagram from the TH rield towards the alkali cor-ner through Ilie CA rield and not through that of the tlloleiitic rocks, as in the diagrani of the sheeted dyke complex. The position of t.his trend was determined by the reak iron eO!1reJltratiolJ.

AII t hese observations lead ta the idea that the ocean noor hasal! complex (Od, as well as most of the in-tergranular ba!'alt. and dolerite dykes from the sheeted dyke COlllpleX (0 2 ) originated in a normal (common) t holeiit ic Illagma. These roeb were clI1Jllaced ill the first. parI of the differentiation process of the tholeiitic magma in t.he magma tic chamber.

The basic differential.ed rocks (ferrogabbros, fer-rodolerites, ferrohyalobasalts) anei the acid differenti-aLed olles (Iellcocrates), such as albite t.rondhjemitic dioriles, granophyres anei tlte albitf' ocean ridge gran-itoidt:> from the shected dyke complex (Savu, Stoian , 1988) originateel ill the residuallholeiitic magma') , dur-ing (he final stage of t he evollltioll of the magmatic ehamber a! depth. Thal is why most of the dykes consisting of such diITerentia(ed rocks were emplaceel among the ot.her dykes of comrnoll basalts and do-Ieri tes .

Conclusions

The lllain ieleas reslllling from this paper are: 1'he OCe'lll. floor haSil I I fOlll P kx (O 1) rrom the

megaslilb ill tlle ophiolilic suluri Îormeel a fidel of oeeall noor basalt f10ws in t 1](' st rueI urc of I.he M ureş Ocean crust on ei 1 her side of tiI(' oceanic ridge (shected dyke complex).

1'his complex as wel! as the otllt'r associaled ophi-obtic cOlllplexes resulted rrom fi tholeiit.ic magma fOl"llH'd in the lllantJe al. t he depth of ca 150 km , dcveloping in a magmatic c!tall1l)('r at. dC'pt h.

The lavas from which fhe rocks of the basalt COI1l-plpx originated flowed on th( noor of t!w Mureş Ocean, alt alJd dolf'rite shectcd dykes i\1 t!te beginning of the initial tholeiitic magl1la differ-" lIt ia(ioa

C'ollsequclltly the basaltic rocks have the c1laracler of nOl"lllal (cOIll11l0n) t!toleiitic ba,.,alts. Except some »pilit.!':; ri('h in l'\a~O, tlle basalt complex is devoid (lI' 111

.1

PETROLOGY AND GEOCfIEMlSTRY OF rIIE f3ASALT COMPLEX 75

Co)emall R . S. (1977) Ophiolites - Ancient oceanIc lithosphere? Springer-Verl., 229 p., Berlin.

Ewal't A. (1982) The lIlineralo~y anei petrology of T~rtiary - Recent orogellic volcanic rocks; with spe-cial reference 10 the andesitic -- basa.llic cOlllpositional range. Andesites. R. S. Thorpe (edit.), J. Wiley, p. 25-87, Chichester.

Fellncr C. N. (1929) The crystallizatioll of basalts. Am. j. Sci. Ser., 18, p. 225- 253, New IIaven, Con.

Gill J. (1981) Orogellic andesites and plate teclonicti. Springer-V"r!., 390 p., J3erlin.

Griffin il . .1., Varnc R. (1980) The !-'lacqnarie Island ophioli te complex: mid-Tertiary oceanic Iithosphere from a. lllajor ocea.1I basill. Chem. Geol., 30, 3, p. 285- :~08, Arnst.erd am.

Hart S. R., Brook:; C., Kl'ogh T. E., Davis G. L., Nava D. (1970) Ancient and modern volcanic rocks: a trace element model. Em'lh Plallel. Sci. Leit., 10, p. 17 28, Amsterdam.

Hertz N.. J ou('s L. 1\1.. Savll H., Walker R. L. (1974) Strontilllll i!:>otope compositioll of ophiolitic and related rocks, Drocea !\Iollntains, ){omaJl'iil. Bul/. Voie .. XXXVlll , p. 11111- 11'.!4, Napoli.

lrvine T. N., ilaragal' W. R. A (1971) A gllide to lhe chemical classi fical ion 01 the com mon volcanic rocks. Con. 1. Emolil Sci., 8, p. 5:!3-548, Toronto.

J\,1iyashiro A. (1975) VOlcilllic rocks serje~ illld lectonic sett:ng . A 1111. Hev. Earlh Planel. Sct.. 3, p . 2,51 -270. Palo AI to, California.

Pearce.1. A. (Hl80) Geochemical e\'idence for tlte gen-esis and e ruptive set.ti ll g of lavas rrom Tethyan ophi-olites. JII A. PalHlyiotoll (edit .. ), Opltioliteş. Proc. Intern. Ophiolite SYlllp. C} prll~, 197U. p. 261 -'.'.72, Nico~ja.

-- ,Callll J. R. (HJ73) Tectonic setting of basic \'01-canic rocks determilled IIsing Irace element analyses. Ew/lt 1'/(1/1([. SCI. LeU., 19, p. 290- 300, Amster(bm.

- , Gale G. H. (1977) ldentificatioll of ore deposi-tion from t race - element gcochemistry of associalt'd igneolls host rocks. In :\1. J . .]ones Volcanic processcs in ore genesis . lllst. l\Jining ilnd J\Jetallurgy and Geol. Soc. Sp(x:ial Pllhl., 7, p. 1-1 '.'.4, Londoll.

Savu H. (1962a) Asupra unor iviri lIP roci ulllilbaL.ict· îu partea cenlrală il geosilldillillului Murc~llllli. J) S·. Com. Gcol_. XUV, p . ,59-73, nllctll'('~ti.

(1962h) ('orpIlI gabhroic de la i\llllă~el §i contri-butii la cllJ\oa§ft"rC;l chillli~mllilli !ji petrogellezei ofio-litelor din mil,.:ivul Droceil . .-1.11 . CO/1/. Croi., XXXlL p. 21] -2%, Bllcure"ti.

(1967) Die IlI csozoi ~cll('n Ophiolitp l'uIllăni,c1l e], I\arpatclI . Ac!a (i'ol. "-Ie"t!. Jlung. , 11 (1 -,1). p . ')~, 70. BIJcliLPf·~1.

(1983) Geotectonic and magmatic evolutiou of the Mllre§ Zone (Apuseni Mouutains). Calpatho-Balk. CeaI. Assoc. Xlf h Congr ., Bucharest, 1981. An. 171st. Ccol. Ceofiz., LXI, p. 2,53-262, Bucure§ti.

(1984a) Melange-ul cu matrice piroclastică asociat arcului insular sudic al Zonei Mure§. Stud. cerc. Geol., Geofiz., Geogl'., Geologie, 29, p. 36-43, Bu-cu re;:ti.

(1984b) The slJeeted dyke complex in the Mure§ Zone (Apuseni Mountains). Rev. rotim. Geol. , Gephys., Geogr., Geologie, 28, p. 29- 34, Bucureşti .

(1985) Structural, petrographic and geotec-tonic study of the sheeted dyke complex in the Mure;: Zone, Dumbrăvita-Baia-Bătuta-Julita region (Apuseni Mountains). D. S'. Inst. Geol. GeoJiz., LXIX/5, p. 41 --56, Bucureşti.

(1988) On the presence of tII", Gro§i lIuit. 1Il t.he Higlti§ Mountaius and its origin. D. S. I/1si. Geol. Geofiz ., 72--73/5. p. 225--236 , BUCUH'§ti.

- ,Stoian M. (1988) REE contents in the sheeted dyke complex of Ihe !-.Iure§ Zone aud Iheir pelroge-netic tiigllihcanee. Rtl!. m/lm. Grol., G'cphys., Geog/'. Ce%gif', 32, p. :37 4,1, llucure~li.

- • Va::;iliu C., Udre::;cu C. (1970) Ceochimia ~i petrologia ofrolitelor dill prima etapă de ,~voluţie a magmatismului initi,d alpin din masivul Drocea (Mllutii Apu~elli). D. 8. Ins!. Ceai., LVr, p. 219-252, Bucure§ti.

- ,Berbeleac 1., Călinescu E., Florescu R., Zămârcă A. (1978) Struclnre ancl origin oI' BUlle§ti gabbroic body (Metaliferi MOlll1tilins). D. S . Inst . Gf'Ol. Gwfiz., LXIV /1 , p. 173- l91, Bucure§ti .

- . Udrcscll C., Neac§u V., Stoian M. (1984) Trends of t.holeiitic magma differentiatioll in the shceted dyke complex from t.he l\1l1re~ Zone (Roma-nia). :!T COllgl'. Giol . Infern., Moscotl. 1984, An. Insi. Gcol. Gwfiz., LXIV. p. 121 - 139 , nllcllreşt.i.

- , Udrpscu C., Neac§u V. (1985a) Petrology anei geochemistry of t he ;,heeted dykc complex in the !-.lnreş Zone, DUl1lbrăvita-Bai'l-Bătllta-Juliţa regiOll (Apu~enj MOlllltains). J) . .). IT/si. Geol. Geo[iz., LXIX/1 , p. 129 118. J3l1cure~li .

- ,ilerbeleae I.. Udrp,seu C., Neac§u V. (1985b) Tit .. "ludy of ophiolites ;tIld island arc l1lag-lIlalite" in thc Băgara- Vi~ca-LlIllcoi region (i\lllreş Zone t\pll"em !-.IOlllll;lill s). D. S'. il!sl. (,'ea/. Ge-ofi:;., LXIX/ 1, p. ():l KG. Bucure~ti .

- . Udre,.:cu C., Neaqu V. (1987) l\Iicl - ocean c1lilractc'rislics of ophiolites in Baia-LupCijll - \'ărădia an'a (DrOCt'd \rO\lnldill~), 1.lJ"ir tt'cl o l1ic~ amI 1)(>1[01-ogy. D. S·. {ilS!. (ieol. Gcofiz., Î'.'. 7:3 (IY8.:;: 1986), p. 161 - 180 , BUl lIr('~ti.

76

- ,Udrescu C., Lemne M., Neac§u V. (1988a) Petrology, geochemistry anei tectonics of the ophio-lites from the oceanic paleoridge of thc Mure§ Zone bctween Pîrne§ti, Troa§ anei Zeldi§ Valley (Drocea Mountains). D. S. Inst. Geol. Geofiz., 72-73/5 (1985; 1986), p. 237-257, Bucure§ti.

- ,Udrescu C., Lelllne M., Romanescu 01., Neac§u V. (1988b) Petrology, geochemistry anei tectonics of ophiolites anei Late I{immerian island arc vo1canics from the Glodghile~ti-Săli§tioara tectonic rise (Murc§ Zone). D. S. Inst. Geo/. Geofiz., 72-73/5 (1985; 1986), p. 259-281, Bucure§ti.

- ,Udrescu C., Neac§u V. , Ichim M. (1989) Petrology of Lia.ssic ophiolites and Late Kimmerian islanel arc vo1canics in the Vata-Căzăne§ti-Ţebea re-gion (Mure§ Zone) and their'o-trace element contents. D. S. Inst. Geol. Geofiz., 74/1 (1987), p. 149- 167, Bucure§ti.

Reeeived: May 25, 1990. Aeeepted: May 31, 1990. Presellted (It Ilie seientifie session of tlie Institute of Geology and Geophysies: June 8, 1991.

H. SA VU et al.

- ,Udrescu C., Ncac§u V. (1992a) On the pres-ence of the ocean floor rocks (Liassic ophiolites) in thc Trascăll Mountain!' (Murc§ Zone). Their petrol-ogy anei geochemistry. Rom. J. Petrology, 75, p. 53-62, Bucure§ti.

- ,Udrescu C., Ncac§\l V., Stoian M. (1992b) Structure, petrology and geochemistry of the gabbroic body of ClIiil.§ (Murc§ Zonc). Rom. J. Petrology, 75, p. 85-96, Bucllreşti.

- ,Andrci J. (1993). Source of the Căzăne§ti-Cuia.§ ~ravity anomaly in the Drocc

Pl. 1

H. SAVU et al. - PETROLOGY AND GEOCHEMISTRY OF THE BASALT COMPLEX

Fig. 1 - Basalt. flows in pillow lava facies on the road (]) NI) bctween Toc and Cuia§ (Drocea M Is).

Fig~ 2 - Basalt flows in pillow lava facies in the erosion willdow al. Visca.

I

PI. II

H. SAVU et al. - PETROLOGY AND GEOCHEMISTRY OF THE BASALT COMPLEX

Fig. 1 - Lapilli pyroclasts level intercalated among t.he basalt flows In pillow lava facies 011 the road (DN7) , between Toc and Cuia§.

Fig. 2 - Pyroclastic rocks with larger blocks of basalts and hyalobasaI"ts that are crossed by calci te veins and zeolites on the road (DN7) between Toc and Cuia§.

Pag.67Pag.68Pag.69Pag.70Pag.71Pag.72Pag.73Pag.74Pag.75Pag.76Pag.76_pl.IPag.76_pl.II