GOVERNMENT OF KERALA

DISTRICT SURVEY REPORT OF MINjOR MINERALS {EXCEPT RIVER SAND)

ERNAKUTAM DISTRICT

Prepared as per Environment lmpact Assessment {ElA) Notification, 2005 issued under Environment (Protection) Act 1986 bv

DEPARTMENI OF VIININ6 AND GEOTOG? www.dmg.kerala.gov.in

Thhuvanent sdc!K*hs*etl Figure l: Csolots! !nd mineral resources ot Ern.lLl!m

f igur.I Gconorphokrgvandlarduseof Erna[ulain

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Atrnerure L C{logy ofKerala . ts DISTRICT SURVEY REPORT OF MINOR MTNEMLS ERNAKULAM DISTRICT

(This..FortisrobesDbhittedalonCwtthapplicatioofo. Envi.onmental cleannc€ {ECl forninirg otatl nirof nrinents except rivers!nd)

Emalulon dhtrict o@upies the Cenirat pan oiKeFto sr!rc dd h botrnd b! Tnchur disaid on ihe no(h, tdukki on rhe easr and sourh e6r, Konalam and Atappuztra dislrictson thesuth and rhe Latshadweep Sea on the we$. Tne disricr is spftad ov€r !n arer of1068 Sq. km. ertief rhe disrj.l coyered an aEa ofonly 2408 sq. kn Bur later on Kutkmpuz-ha pan.hsyar ofrhe N€lumkandam btck, tdukkidisrid w6 atso anoched to ir and rhe disricr anained thepresnr ae ts mdimun tenerh jn & E-w dnection is $our.18km and rhe maximun lvidh in N,S dnecton is abour l8ko Ernalulam disrict ties b€tw*n Nonh tanrudes 09r 47, ir.. M,l lu,L0 44. and Eas longitudesT60 t0 0i"&dJ7t05 2.1 KochikiownasrheQueenorArabran\earfie headquaneN olEmakulanr dkricr lrs nraximdm tensrh h k a frajor pon c4 on rhe w6t co6torlndio. Ematotm is having a corstti,e afabof 30kn. Thedisricr k wetl lonnecred with a aood nehvork of rcads and raitways. The Nedumbssery rnremadonal a'$on 6 bcated in lhe disrricr

Foradninistative purloses, rhe disFicr tsdivtded inro Mo rvenue drv6,ons and seven raluks. Mu!$upuzha Evenue dnision wirh Muvanupuzha 6 ns headquaned comprises of 43 vjttases betonging ro Kuniarhumdu. Muvarupu2hu and Koth@sngdM Gluks. white Kochidjlision sirh iB headquadetsfi Kochiconsists of 7l v ilages ofAtu!a, Padvur, Kochi and Kanayan!.ratuks. There are l4 communirl dev.lopmem bleks,88 8mm panchals*.eldv municipahiE\ lru onc corpoE on n $. dndd The disvlcr h6 a poputarjon.ft2. 79.860 pemns rvi$ t6. t?.602 hales and 16,62,258 6 per 20| census.

Thedistict p.riyarand isdrained by rhe its rtburaries in $e nonh and Muvanuplzh! Riler in the $urh Periyar, rhe longes rivcr in thc state \irh atooLtengrn of244 kfr oflginaFs lrom Ihe arddmom hi|s ofltre Wenem Chals norvs ii aNoftherty dt€ction rhen,n Nodh,wes 'nniallyod direcdon as it flows $rough IdukkidhEict befotr

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2

a E -. t f 6 XiE r:l Wffi'"'oit" enterins Emalulan dislricr al Neriem&galm In rhe diricr rhe nver rlkes aimosl a slaighr line coure mughly ih a Nonn Wden direcrion and at nar Bnurharhanketu dam. ir isjoined by majorlribuhri€s cheruihoniand rddalays. Funherdownsr@ d Aluva, .he river biturcdes inlo two: lhe Msthsdavma fld lre Msealapuzhs bruches. The Mdgalapuzh! bBnch joins Chalakkudy iver sd mplies into de l-akshadwcep s at Munambsm, and the Morthandavm! b6n.h nops sudwdd: ihrouCh $e Utlhyogammdal area ad joins rhe Cochin backwarer syrem (pd of vemblnad Lak€) dt v@puzha. The Periyar is a p€Mni,l .i!er ed h source or drinking warer lor sevcml major torns. The ldukli dam across the Peiyar gen€Bros a significdr proponion of Keralas electricd power, -lhe Muvatr$uzha Rivcr is famed by the entluehce ot Tnodupuzna Rivcr, Kaliyar Rivcr ed Kothmanealm Rirer st Muvattupuzha. These rilets oliginare aro6 rhe Thodutuzha resne foresr. The MursltupuzhaRivertakesasugh edl-wes couN up ro Radamo8olm ed desier it nows topads south leaving rhe di$ndssud of Puhur. In $e upstrem e€as rhe diainag. patrem in bolh Periye dd Mulanupuzha b$in se tellis ro subftllis. ln the low€r reehes dendlitic paftem of dEi.ase is

Ernakulam dhtid is bo'nercd ro $urh-west by vehbuad Lake wbich is rhe laree$ lakc in KeBla. B€sides Emrkulam, rhe lake is borde.ed by Alappuzha and Konayam districa. Tte lake h sep@ted frcm the Lakshadwcep S@ by a ndow buier island and opens 1o the s at Cochin. And al Munmbam tunher norrh. Th€ pol1 of Kochi (Cochin) is locatcd al *e la&e! southem outlet lo the S*. Thc sftrch tufr rocri -12,; ro It ,,,,rdn Azhi, is populdly l$own as Vaapuzha. Cdals link dc laie to oder loaiallakesro lne norlh sd sourh.The ponion ofthe venboad Lake locaed in od aoud the Kochi nrinldd k knoun a Kochi kayal. The lake hmN mny sn islands and in Ernakul@ dist ict itself it hosrs islud like Vypin, Mulavuk!4 valla+ad,n, Nillinedon Isjdd erc. The lake is a pln of Vembanad-Koi wetldd srsrem which errends liom Allppuzha in the south lo Azheekkode in the nonh, naking n br fd, lndlas lonsest lake al.ju$ over 96.5 km in le.grh. The lake is fcd by l0 riveE norvins inro n including the six najor rive6 of cennal Kenla n@dt de Achenkovir, Manimala.Mm&hil. MuvottuDuzha" Pmba snd Periyar. The tolll 6r* ddined byrhe lakc is | 5.770 kmr. which accouls lor 40% ol the d! of Kemla. us annudl su.lace runo1lof21.900 mh acoounts for alnost 30% of the tobl surloce water rcsoure ofthe

'r he lake has becone a major tourisl locarion due lo ils scenic b*uty. The vembanad lvedand system is $e lar$st oi rhe rh@ RdF Sircs in L\e sral€ of Kemla. Bur Vcfrband l,ake hs becn havily ftclaifred cver the cou6e oi th€ past entury with rhewaterspreadarearc,juci.giofr 290.8tknrin 1917!o227knrin 1971 and2l3.28 kn' in 1990. In the same period alnost 63.62 kn ol e$xvhile wald spread weE reclaimedprindily lor formation ofpoldeNed to enldge $e extentoftheWellinston isled ofcochin pod. The lake faces a major ecological crish ad h6 reduc.d ro 37 per cent of iLs original !re!, 6 a result ol lmd r€lamation.

4

On the b6is of land use ihe distict is dilided inb ttuee unks dble, forest lud dd q6te land. Major pan ofde disnid issable iodqhich includes irisaed sd unirigared Jaid. Forat is mosll)i in rhe.asr, wnhin whicn soDe aras are developed 6 rubbertd cshe* plantltions. enensile ware led fomed ofhar! lakrne, unsuibbleforcultivation lies in r,\e midlMd region. Mosr of ths ma is covered by lareriric eil. Foesr lom soil occuN the *t and rhe all0vialeilisalongrhe coasi /FlA,ru ?.). 'n

About 33q/o orthe total area olthe disrict is cultilable iand, l0% is under ioftsl cover i.cludingrcs@e forest md plentationsr walef bodies conniture 5.1%and built up ar@ consriiutes neely 20lo ofthe rotal ma

An aea of26,825 hectaEs is undd inisalion (nd rea) in dislricl Periyar lalley 'he rnigation poject qith a bdage ar Bmhlhdketu which uses 6e rail mce waler of Sengulam, Pmilar ed Palli€sai fiydrcaiectric projans and Chalakudy dive$ion polel e soue for canal inisatior in the disllict. li'e mojor cops unds iftigalioi ii ihe disrid are paddy, coenut, rubber, baana aid arecdu. Paddy is cultivared in moE rha( one seaon. Rubber k $e major crop in the disdd followed by Coconur, Paddt. and Badana. Spices, A.sa nur, oil seeds 3nd vegehbles are alsocukivakd in thedistrict. The a@ faLlingundff fores ksiven in the

Raintalland climate

E.nakulam distiict has wer monsoon !'pc ofclimare The disrid e+eriences hery minlsllduringsouthwcnhonsoon sdson rbllowed by nonheasrmonsoon. Dlring rhe olh..nonths lne rainfall is considenbly Jc$ Marcb, Aprildd Mardedrehone$ rorl'. De.enber ro lebrar: are$e -ordeimo1.r. The rlhtiid €eive on an average 1159.2 mm (based on 1901-99 datE) ofdinfall annualiy. The dnual rainfall reg6 fom 32311o 1456 mn fi differenl places ofihe

The Rinfall G les in the westem pan of the districl od gradually increoe iowards the esn. Mdimuh lainfaiJ is received doundNerilmogdm s@ in the astem pan vheE the nomal annualminfall h foudlo be 5883 hm. \vhile Kehi, which is in the wescn psrt rekives eound 3233 mn minlall annuallt. The annual arerase mint llof Emakulmdisticilrcm200Tro20ll isgiveninTrble4

I BIOSPIIERE RESERVESAND WIIO ltFE SANCTUARIES

i,

ntributes neafl) 67.4y0 ol rotal ainiall of the )ear, lolloBed byfie nonh-ea$ monsoon which contibures nea.ty 16.6% and rhe batdceof l6% is reeired duriig rhe month oflanuary ro Msy as sufroershoreE. Meteorological Parameters

The meo monthly maxinun te(pe6ru€ trges lrcm 28.1 to 3l.4oC and th. minimum tr8es 6om 212 to 26 oC. The mdimum tempestuE occuu during Madh sd April monrhs dd fie minimum renp@tore oeu6 during Deemberdd January months

6,2 Relative Huhidity

The humidhy mng6 from 68 to 89% dldng fromins hou6 and 64 ro 87"/" durin8 elenins hoots. The maximun humidny is observed duriis May ro Octobermonths.

Evaporation is more durin-q summermonrhsoijanuar] ro Apriland i is lor durins the drn! months May b Aus!$. Tlre marimum mre of,1.8 nfr per day is recoded ii M@h ed de lowesr rate of2 6 mm is ccorded du.ingJuly.

sunshineang€s fom 4.3 !o.9 7 houE/day. MqiDum sunshine is during the month of February.TfiemonthsofJunetoAugustrecordrhenininunsunshineduetodecloudy jn skt. Cenerally eood sunsnine fiouts ffi Ecorded rle Donrhs olNovmberro May.

The wind sped 6nses ftom 6.7 to 10.9 kfrnour wirh meon spftd of9.l km/hour. The \:dd )peed n | o! nc .l-e oerioo fton Mar.n ro \ep'erbe. 'eh 6.6 Potential Evapotranspi.rtion ilrETl The PETmigesfrcin 91.5 to 159.2 mm The maximun PEToccursduing March and n'nLoumoccu(durin8.lune.ThePETisiesrharrheminial iom MavtoNovember :'d.d € rarer d'oh: or rc. ,ar6e inro gro. ,o \a.tr r-o'n,

7 Geology -lhe ceoLocically two disrind lidrounits aE dncemible in lhe area. ealem pan is occupied by had mcks r€pdsentide Pre.anbiao meFmorphosed rocks while rhe cosraltad in the wesr is covered by sofr rock or the unconsolidared co6Flailuvilm. Mato! panofde disirict isGcupied by chamockne and noi8marire groups ofrocks of Precahbrjan age. Tbe chdockile group is composed ofpyroxeneelanulile, msglerhe quaditc dd chmockire. Cbarnockire, which n very widely di$ibuled, is code- grained. Sranuinic and dark colotrred. Pyroxene sranulire and fr agietire quartzne occur ds linear bands. Calc-sneks and qu.nzite ofkhondahe group are the oldest mcks of rhe area and drey ar€ seen 6 linea. leisoidal bodies wnhin the chsmockites The inismatire group includes bibrire gneGs and quanzofeldsparhicsnei$ which aft ne{ ro chMekil. in abundance. Tl* older octs e inttud.d by borh &id Gy.iit ) and bdic G5bbrc bd dol.dL) iiinsiv.. Palchy outcmps of W&*!lli b.ds, onsisling of pebble M, grjt, tiable sddstone dd vdiegal.d clay is sq in rhe 6t m Flt @und Eda$alli, *nmseri .!@ Both dre Wdkllli beds 6 w€ll 6 thc [email protected] Dcks e {bj*1ed to inleN laleriris4ion, which h confined lo ti. midlsd Fgion only. Tl'e c@tal Eact is colerEd by Qudtendy ediments li\e b@h snd, pd@-b€&h ridge deposils (snd), fl@d plain deposirs {smd, silq cby) ed li&l deposirs (clay, 6ud) fFiquP ./r. Thc seolog ofthe disuicr given lbove may b. rdd with $e Geolog/ of Kd.a sh'ch issiven a AnneruR I lorbdre' undmhoingolgiolos@l lucc$ior md stdtienphi€ sequ.nc.. I I I t, i, tlll ltiiuii b ifii ll t I ,t I il iiii il'dildl{ Jl I i; ! ;i:it iiiii "lt llriI 'iiiiiif;ihli f,E !l ;ii!iiii ti :1it;tlr ,E i. ;iitiiiii it l!l -! I : ll rl r.ii : iiiiiiiii i,i Ir ! | riitlii EEEaEr* lii ii i f ir BI r!E EL{t{Cr: " iiliiirri

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i, E i! : ei i 8 Geomorpholog/

Thedi$ici isdivisiSle intolnrc physiosaphiczones.s {i)lhecodatptains in rhe w6r. $e midldd reSion i! lhe €rsl tud the secp ro very sreep hj s jn ihe Bcmnoe pan ThecostalplainhalowlyingaEa,withsmaximumetevationofa@und t0mrowards the ca$em pan, chaBcterised by backvaGr bodies, ma6hy lands, wdy na$ ed a|luvidt plains,whichdeliable forfloodingdurinsthemonson. Themidldd region h6arc ing topographt wilh low hills ond nm* vatt€ts. The hilh ee senedDy covmd vi6 tarc.ite of lare ticeilsed rhe valleys are atleviared, Tne.e8jon has a verj, genrte ro modede srope lmh edt to wc$. The 4tennosl pan is a ruCCed rerEjn wilh n€ep sloped hi|s and snallsumnns. !aciually forms lne foolhilh ofrhe westem chali Etevarion ofrhjs tenarn h eenemlty nor€ rhar 300m above mem sea tevel. As rhe ma is covercd by foEn soil, thick loresl dd cukivation ofcsh cops iike rubberabd psppercd bc*en in rhe

9 Soiltype

On the bdis of moohologicat fanu!;s dd phystco-chemicalpropenres, rhe soits ofrhe district arc ci4sified as Latedric, t-tldromoehic satine, Bmwn hydrcmorphic, Riveine srhrvium dnd co6hl 3lluvium. ji Laleflnc soil the no$ predomina soiJ rype ofthe disricr. tn Nluvadupuzha_ Korhafr$salam, Kunnarhunadu and pm ofAtuv, ratuks tarernic sojt is encouEed I hese solh are wll drained. tow in orsanic maoer and ptanr nutri€n6. The mojor cops grown are coconur. hpioco, rubber, e€enur, pepp*, c.shew and spic6. Sna[ palch6 or hydromoehic saline soit e en€ounlrcd in the m6rat mos of fie disricr in Kanayannuraid Cochin ratlk, The tidat backwa&6 @ntribule to the satiiiry of rhe soit, co.onui is efown in $ese soik. BroLr htdiomorphicsoil is rte *cond nosr pEvsled soit rr?e of thedisio&d they areencountered in valtey borohs. The soilis enich€d in clay co.le ddptanlnurrienrs. The soil iss!ired for pa,jd' cut!jldrion.

Rive lne aliuviun is Esfiicred lo $e btuks of rivels aDd then riburaies. Th€y are cofrcosed ol sand], b ctayey loM and aGenriched in pta nurrienB h is eiled fora rarge vhery or crcps like coconur, paddy a@cdur, peppef. vesdobtes erc. In cochin taluk and $e Resleh pans of Peavur and Atuv. raluk caBrat a uvjun h encounrered ,nd isefrpnsedofs.nd and clsy. Coconulhthe majorcop in rn€sesoits

10 Grou ndwate. scena.io

Coundwarer gene€llt occu6 under phreadc conditions in weathered and riactured cry$alline rccks, ldternes and uncpnsotjdard coasat sedtnents. ll occuts Mder sami conrined to confined coidnions i. iiE deep seared tEctuEd aquiter ofihe cry$a|ines

nid. KerL: seE t11 Ncks dd Tenidry s'limenis. The wstheEd zone in the cryialtines below lcri $ g@d aed on nature ofaomdion, fie aquifer can b. clasified i.ro hErd @k dquifd dd

The disriq is endo*ed with good !ale. esouees 6 rhe Einfall ison€oirhehighBt in hrdia and aho nvo rives Muvarupuzna and Peiryar ar€ nowing in rhe distric! Porendsl aqujGE occur all along the codrat altuvium, whose rhicknes !&i.s fmn a few mercs to r00D. Dep$ ro walerrable is 0,3m.Groundwater developmenr is rhe@ is mainty by mee\ ol dug welk LaErn.s a€ rhe iorenrial ,quifers for grcundwarer. Depfi b wxrer level mnges fom less lhd a melre ro 3 metres. Bur fie problen wilh taredres h groundwater drains ofimnediately after rhe rainy seasn. In crysbllines srcundwater occurs ri the weetnered and pdty werhered, fracrured and joinred ocks. Boe wels dug in potenial f!"ctur€ zones givehigh yields. There de lbour 55 Narional Hydlogmphic $arions in lhe dhrict i.e., roughly one for43.8 sq. kn., which would monitor tie wrr kwh ii the @ i/Frrzz l).

$n.r. cBhshE 1 i !l Ei - tl !{ E; E i: I ii i: lr : i.i z 5C t ls t :t,. 3 e; a : 6 id I r :"6 *- F! ! 9;! I i! a !! I i i: I t; ? i !: x ! ; ! r5i E; t E: i ! ! EETEB

6 z >: '9- i :'ll l tE t E:ES 3ll :: €3 :ll'il . 9 E; ; ,tl d i 6: = 0 lltN ;;

: : .i ti I rE:r 9i; ! ! ; ! t E.: i i i ; P rE;€i Ea ,i:::_i i ! ! 3 rr! L, I ENffiE The area com.s underzone III and indicates moderare seismicirr, /F,szE,r.).

12 Mineral Resour.es

Ihc mjienh found in the dilbid arc graphne and chira ctal,. Gmphne is found in assNialion qiLrr the Knondalire crNp ot ocks

Cmd deposils ofgaphne ee noticed in ptaces tike Avoii. perinSuha. Memadmgu ed Kurhatukuld. Oneniningte6e k gruted ro MAThomson c€phire Mines fldCflcibte works, velldad, Thiruvananthapurem io nine Eraphire in l.2t4J hectares of tand in (alloo&ad villoge, MuvarupuzkTaluk. kon ore is reported fmn Mangatd and Nadorayan aE6. The diiricr h6 &nl, good rcsources of chinaciay. china ctayof pimary origin n reponed hon amballoor dd o$er lea chiiaclayis normined in rhisd'snicl

Ordinaq' eafrh h the comnon name used for $e sois. S.jt is made up ot rhrce majn components- n neELs rhar come fron ocks betoworneatuy. organic naiter which is rhe r€mains oiplants ud animah thar use rhe soil, lnd rhe ljving organkms rhar ftside in the soil. The poponion oi each ofrhese is imponanr jn dereminjng ihe lype ofsoitrhar is presenr. BLr other facrors such sctinaie, vegelldon.time,de suiioundinglenain, and even huhar malities (eg. fa.ning, grine, gade,jns, tandsepjng, erc.). are aho inpondl jn rnll'rencinghow soil is fomej and rhe qpes ofsoiJ that occlr in a pdicutar tandscspe. The fomarion of soih @n b€ s€en 6 a combinaion of rhe pmdlcts of wearhering, srudueL d&elopmentof$e soil, diF.mriarion ofthat sructure inro hori2ons or lsyers, sd tasnl, of irs hovement of tmnslocation. h facr, lhefe are maiy Lvays in whjch soit may be nlmponeddwaylilnlhelocdionwherejtwasfi6rforned SoitsreFesenr oneofthe most cohplex3nddlramicnlturalsystensdd ftoneoftk lhree majornaruBlresources, orhe] than air and warer Knowledee ofrhei chemicat. phlsical and biolo8jcar popenies is a pFrequisne both lbr susrlining rte poduciviq, of the tand. e.e. ,gricuttuB lnd for

sru.(emLastd, i! conssdation puQoses. soil isan int€s6lpan ofa tenesrial soslstem ad tulnlbnune.ous tunctions including the ap&ity to generare bioma*aid the rihering or bufenng erirn'es bc1*ten the atnosphere od the gloundwarer in de biospherc. Soih have 6an! rmpo@nr funclions. Perhdps the ben appreciared is the funcrioi tosuppod the gronhofagricuhuml aDd honicuhunl crcps. Soil is rhe mainrtat ofagriculrure ud honicul&.e, tbming us r does the medium in which sroqh and ulrimaElyrhe yield of food p.oducin8 crcps occu6 Fame6 ud eadeneB have rvorked wnh rheir soils over many cntun€s lo produce irctsins amounts of f@d to keep pace with tie needs of a bu46ning world popularion 'lhe soil! natunlcycles Co a long way in ensuring rhd $e soil can povide an adequate physical, chefrial ed bioloeical medium for crop erofrh. well s being essnrial to ^s asriculture, honiculrure. foEstrr dd naru€l and sem;naluEl sysrens, soil also Plars 3n inpond rcle lor our launa. Th€ soil itsellconrtins m llions oforssisms. the exacr naure androleofwhichweare$illtfyinsroderermine Undoubtedly,lhesoilflomand&unaplal r v tal role in cycles whlch are fundamentalto rhc abili,r- ofdr. soil !o suppon ialural and s.minduaLvegddiod*nhodaddhionsoffenlllTtrmdorherstrFponnechnisms. lhey bfeakdown pLant debrk, rake in components lilm $e ahosphefei aerare !h. soil rogethef

*ith any other functions thal make the soLlsuch an Lmponanr medrtrm cttt\{tcntu,' of\oilr(odindr r.nlnah[ in ]tu diarnt "nih) fuprd Tre bpo-lilhosequence alorg wilh vlrillion in rainfall, tempemture and altedare wer and dfycondirionspaniculan)' from the wdem coasl to hiSh mngs in$e easand sailt flowing riveN ead to thedevelopmemofdifferenlqpesofnatualvegeratlon and soil. Thesils can be bFadLy grouped intocoaealalluvium, frixedalluvium,acid salin€,kari,lalerne, red, hill, black coton dd foresi soils. Soil msp eiven below mal be Efercd to lind our its

Th.r. soih .l nrriie origii a* id.nrlied along . sa$al plains and bdin latrds 5 a namlv$rip. The elevalion ofthe.oastalarea is g.icmlb beloe im MSI- I[eareahashi8h \ra(erGble ed in some arels ir reaches above $e suda.e during rainy $ason The eih ol

rhe corstalplains de very doep *nh sand) Exlue.lhe rexrure g€neraLly r.iges fom snd to loanysand sith g€yGh browr to €ddish bosn and yellowislr ed colour' Sand come Dtrgei lilh 80% and cldy up 1o l5%. Even though lhsse nrils hale high w.ler rable, 'he Narer holding capacny is poor dre ro repredominanceolsand Coconuristhcmajofcrop

iD de aEa. Cashew dd odrer fruil rees are also grosn.

sFi.t knl: nd.:15 These soik e derelopetl liom fluvial sdiments ot marine, leusrine sd .iverine stdiments or its @nbinrtions. 'ft€y o@urbelow 20m MSL in the lowlmd ploins, b6ins, valLeys antl alone $e bdks oi major i!e6. The mixed alluvium is mainly noticed clos to co.eal allulium, Kunoad dd ldjaoent area and kolc lands ofThrissur dGFicl. The soils are frequently tl@den trdsubmersed. Thesoihofdepresions and brcad valleysmsubjec! roocGional nmding&d stashdion. TheSoundpa.ertableol$ese$ih isgddallyhigh and il r@hs abov. ihe surfo& during ainy se4on. A wide lanatioi in &xore is noliced in thesesoils. Sa.dy clay loam ro cloy h the prcdominan.lexru€. sandy lom soilsaE ako mer wi$. Lighr ser to lery dark brcwn is the common colour ol the soil. Paddy, oth* annualsand s.enalcrops like bdana,lapioca bd vegebbles are EroM he!e.

Acid saline soik arc present rhruushout lhe coasBl area ln parches wnh very- lirie exrem. MajoraEaofthissoilis identified in rhe codal tracr of ErnakLlm, Thrissur fld Konur dnticrs. The dea under lnse soih ampise of low,lying ms6hes, warerloeged aid ill dmined d6 nee the .ive6 and $reams, which se subjed ro ridal waves. Sea and backwas tides dale fies soils saline. During monsn seaon, when dinwatermd frejh

sate! ircm rives enier the nebs, salinnt is panially s6hed oil The arm underrhese soils

occur mosdy on pla'nsalorbelow sea lelel. A wide vaiation in texture ftom sdy lmm ro

cbt is nodced with dark srey to bl@k colour. Paddy is rhe only crop rhat cs be oultivaled,

Larerite and laterite soil ee lhe wearherin8 producb of rock in which s€6i cou4e of qealhenDg and nineral tanslomations take place This involves renovll of bases ond subsFntial los ofcombined silica of priBary diiedh. ln lareri!e and laleri!e soih. over acidic rocks, indualion add zonation aremore pronounced This indurarion isseater ilthc

noncontent n higher.These s.ils hainly occur in rhe midlands and pad oflowlands atcn

.levarion oi l0 to l00m above MSL s a $rip between the coasFl belr snd hilly midupland. The area comprises ofmounds and low hills wiih genrle o sreep slopes. Lacire soils aE generally sunable for oo$ of the dryland crops lr is dainly cultivaled si'n coconu!, arecanur, bs&4 rapioe. vegeGbles, yams. pepp€r. pineapple. lruir tres er. The percenheeofgs€l@nlenr inthesoiiud rcduced soi dep$ limilsthechoiceofcrops.In

atefit. ourdopp€d area wnh shallowsoils, onlycashe$ can be gm*n whh ve8elables. Thehillsoih mostly o6ur above o elevarion otS|)m MS!. Th€ fts k hilly md hs hishty dssecled denudationalhilts, etonsard ridges, rocky clifs and na@w vall.ys. The geneFl srope dge 6 abovc l0%. The textuE of L\ese sojts senedlly mge ftom toe ro clar toan wnn average gEvel ontent oi l0 b s0%. In addition, srones ahd boutdeE m noried in lhe subeil. Tl6e $ils Mve eddish brch 10 yeilowish Ed/smng brcM @rou. C€neEliy, 'i.cr6e in cla! cont€hl is.oriced down rhepo{iie. The depth ofrhesojtveies consideEbl} aom 60ro 200cmdepqdingonlhe tie ofrhe tand.erodibi[ryofsoitand pas€os;on These s0ils aE monly friableand subi.cr ro heavy sojterosion The dea issujbbte toraI dr]tad orops like rubber, coconut, a@,nur and ffun rees based on rhe ropoeEphy. Cops such 6 banea, pepper, pineapple, vceeiabtes ctr bee.own in tbor stopes.

Thse soilse developed ftom crysEttine rocks ofarctmedn ase under foEn cover The' occurarodg lne sre.n pad dfrhe slse, eeneralty above an etevarion of3oom dbove MSL The &a is hillj, and mounlainous.wnh st@p stopes. es€Anenrs, elongared rccky sumnjts and namw v'shaped wtJers. The depth ofrhe $jt laries considerabty dependjng on eosion and vegetative covei The soiJs aie senem|y immaore due .o tow weathering poces. Rock ouarops and $ones ae noticed on the $|li?!ce cnehsic bouldeu under dlfercntshgesofweaderinearenoricedinthesubsoit The rex[fe ofihe sojtdges from sandy clay loam ro clay wiih reddkh btuwn ro very ddk brown colour. Foleslrees, shrubs and grNes ar gmM here.

iDrlhhDr5tnr Kfraskk i 50t15 KERALA

LEGEND f codclailuvium IAlluv um EAcld sLine EKa.isoil E Lareitesoil Eq 8ed soll EBlackcotton5oil-Hillsoil EForest'oil

DL$dSu eyReodd,Ersku:F05 forcoi{ruction orbuildings Since Ususll) ordiney earlh h mined rbr lelelingofsround drdinary earlh isvery inpodstro mankind. ir i5norwisetonineordinarvdhfornllinC of roads dd inti$lroooc oromar) puQoscs alone Horeler, for the consruction 'rher Depadment of Mining ud .t"O u* obo,n'n, oudving Permn ['om Oe "*n ^ pedission o{D'pannent ceology Miiingand tonspodine ordinarv earth/silwhhoul the olMininedd Ceology isan ofience Depadn'nlissuespasiorransponofordinaryeanh' h notconcideftd 6anineolniied for Dealeas license is not issued lor ordinarl canh as il

r? 2.? ordiniry clay (tile/brickclavl rmge ofg€ologiqlconditions and 5re Clays and clay ninsals o@ur undet a f,nlv iinited magnesiun sodrum' or produced b! veathqing of silicale minerals conraining calcilm sollb le pola$ium ecting with csbonic acid @bonares Md bicdhonsrcs' Th ese Dmducis aluminum silicon'and oxygen sre removed by Sround wat€r, while the remainingelemenb offomaiion In'lude combioe wnh water ro p.oduce steble cltt mineBh' Theen"innhcnt georhemal Ields !'lcanic dePosirs ad'l soi horizons. cotrtinendl and narine sediments, altention ofrccks ro mlnerals can pfoduce \€a$ering ock fomlions Extensile 'la) €d aL lhe sne offie reLarively pure clay deposiG $al @ ofecononic inierest Cla! fo $e onc caiiied a$tv or @nsponed and pareni rock k knotn as Prinarv or residual clav €6ons Ihe lbmer is purer deposiied ehewhe.€ is known as seconddy cbv Forobvious qlanz ed ion oxrde 6 wilh le$ impurily (59-15%),{hilethe laner mav contain mica' deposirion and post- i'nptrrites. Oeologi.tl l&rofs such s @nditions d lhe time of prcPefties of sediment deposirional chmses hav€ u idpodanr inilu€nce on the pefiods ofmans civilized BuiLdings and utensik mdde of clav dde back to lhe earliest with his hislorv Tile and brick . developmen( &d n\e 6e ofollv is intims&lv associated archnecluc whlci kilN ar. closely ssocialed witn KeBla\ cuhur€ alrd mditiooal 's continusd in dodem buildinss slveri nel'ls in the io\4andsand midLands In KeEL! tllgbrickclayoccuE in rne serland s/padd) as mantrlb'trtreoiroolins nooing' Theclalextaded isused for a *riet) ofptrrposes slch (nsnualll made)' an'r ud d*omtive lils,wirecut(dechanicallv nade)aid odinarJ bricks Keola have prcveo har ponery wares Srudies caftied out in clav mitring aEas ol $aie and rhe subsequenr increase in unprecedentcd incEase in the dev€lopmeor keds ofthe mining' have l€d lo mprd Ihe resource extr&lion scenarios esp{iallv ihal oi clat dcgrddation olihewetldds (paddy neld9, which issielificdny reilect€d in thedeclinin8 e8ricultuBl prcductiviry ol lne shre. MininS ol clafs several mete6 below dre presribed levels, water dEinins fmm lhe unaff4Ed paddy lands inro th€ adj@nr mine pits, dd subsequentpunpingofwaterlorfuftherminingimposesvereproblehsonth.hydrclogiel regime- lowsing dre water bble and cFatins srse watr shonage prcblens in thc minins aEr The additional exp.ndilure incurEd to neet $e adhwa&r requiren€lrs ofthe peopl. lilins in al6 adjace ro nining sit€s is increding yer aier year, which sdemin.s rhe shon Gm donomic benefils ofresoure exn&don. 'file sd brick clay mini.g and irs pmcessing p@lide mploydent oppoftunilB ro a co;sidemble section of the people in the midland trd lowlan'l sr6 of Kedla. Adding ro rhis, dousdds of laboreB intheconsEuction indusLaalso indtectly depe.d on thc producB inanulactuEn from $ese clals Under ftese circumslances and aho with esPect to $e demand i.cuned, onllete restnclion ofextBction activities does nor pmveb be liable. ln de study rcpon publilhed b) Nalionrl cener for Edn Science Studies on rhe inpact !r clay mining. following rmnhendarions were aiven with rcspec! ro lile/brick clay minrngl "h is ot imninenr impoiance to r;d |ale rsdom ninins nom ihe padd) fieldtNedsdsof KefaLa by allowing only locarion specilic resource exlEcrion under wellconceiv.d g!idelines.Ir is aho crucial ro limit the extmction olrLe!nd bick clats io meer indigenous and localdemddonly. This is !o save the prine agricultumlldd md aho b inclse the rice p.oddcti.n in the as. 'ahe deprh ot mininB should be dsfrarcated so d to rcSulare mining wirh respet to rhe wacr hble condnion in rhe suhmer seen. Ako, adequaic nreasurcs dc to be talen !o esenerare de narumlground !a!erkble usins the srored warer ir Lhe clay mine pns ior inigaling the agricuLtural crops oflhe hinterlaid d*s. ThL till enhlnce the net agncuh.al poductivny of the dea in addition lo sEturaling the aquifer s!$ems in rhe him.rldds. ApaEness credtion among fte p0blic abour the adv€Bities of cla), nirins and 6 well 6 $e economic benefiB of using clay bricks for con$ruction ptrrposes will seNe in the pol*tion ofour wetlsnds/paddj_ ri.lds. Recycling olbuilding maenalsshouldahobeconsideredinordertoredlcemlnineoltileandbrickclaysThe abddoned clay njne aEs Gn behind 6 fallow landsorrvatsr logged are6 can be usd for productvepu$osessuch6fishfampondsortrisarionpondsthalpronlsesomeutilityro

tu socie.y. Aho, suilalie guidelines should be rlzmed ro sreaniinethelile ud bnck clar, DlininsacLiviriesofthedateonanecofiiendlbash'

The KeBLaConswation ofPsddy Land and wenand Act,2008 and Rules madetheduider which *as enacted lor conseryalion ol padd, land and wenands of Kedla imposes ffiidiom in mihins of ila/brick clays in such 416. Th. eid Acl ud Rules ae implemented by Rfldue Deplrlrnenl. In addirion. Govemment have selup Disticr Expen Committe b noniror od conFolthe ninins rclivities ofordinary cl!y,In KeFla Minor i,,inml conc*ion Rules 2015, it is mandated th3r No Obj€ciion Certitde from rhe DktiicrCollector6ncemed,basedonrheEcomfrendarioioltheDiniicrExpenCommnlee

.onsriruted by the Govemnenr in rhisregard, is to be produced b] $e applidt in the @ or application lor ext6lion ol ordinary cla). ln addition, B$k suMlee liom sr Narn,nali,.ed or Scheduled Bark ar the.deofRr.300 (Rupeesdree hundr€d onlt) p€r cubic for the pu.pose ofreclamation ofpiis th.r qill be lornen aier quarryine in rhe 3M 'nc.E pcmtued, in !6pedofapplicarion for exrdcrion ofordinary cl3y Ba*don rhe reques of

de enrepMeu6 sorking in tile,brickclay based indu$ry. Colemnenl have innrucre! the Depandenl ofMinins and Gslosy ro cdy our suryey lo idenlit the mineable rile/brick (1,) deposiL' olKemla ard rhe ro l in r\i. rcspe(' . p'ogF.inC The disrnd has fairly g@d Nurces oftikr'brickclay. Oood depositsoftile olaytre noti@d

along rhe fio.d plains or Kalaliy, Pdur and Nelahodu de6.

In Kemla Minor MinedlCoice$ion Rules,20l5, the odlncry sand is deined as sand used for noD-induslrial purpose. Thn includes bolh river sand and end excavsted frcm inland

oreas likepalaeo chann€h. Since s sepade Acr has been enacr€d by Goremmedr of(era a nanrelr_,The KeElaPrctection ofRllerBanksand ReguLarion ofRemoulofStud Acr.200l ( rerealier relefted ro as sDd A( 2001) snd since the minidg ofriver sand is conrolled bt R.venue Depademb! vinucofthe posea confened bt$esaidActand theRules msde

lhereundef, the Depanmenr ofMininC and CsloSt now resularesrhe mininC ofsand *hith

do nor comes underthe purview olSand Act,2001

']he ordinary sand (oth.r than river snd) occdc in fte palaeo-channels. The word paleo

chdddelis aormcd froo the words paleo or"old.'and chadnelr ie.i a paleo{hanne r an old.Mnnel. Paleo-channeh sedeposils ofuncodsolidstd sedimenrso.sehi{onsolidaled

sedimenlafy rock5 deposited in ancjent, corcnrly inscrive firerand stem channelsrnems

These are lypicalrivedne geonorphic acarurcs in a lacation €pr.s€ntjns ddinage $reans riveN, rivule6which were no*ing either ephemedl orpe€nnial during the pdr rime ard no{ nands either btr.ied o.lost or shift€d due lo recronic, geomorphologic, anthropogenic

pro.estacrivities. as {elLsclimltic chanees. When a.hdnel csses ro bePal1oran active

nv* syslemi n becomes a paleo{hannel. ln order ro raF the odinar} said occumng Ln

i palas-channels, the Depdhdr eirasled fie study oridenrindion oipalao-chsnnels in nEor n!e. b6ins ofKemla to cological Sutuey ol ldia (CSl). cst resonen to rcmore sensng studies using sdellite ifrag€ries and delin*ied some of:he palaeo{honels. floseler, sin.e such dcposits allls in paddy latul/wedands of Keals, il is difficuhro eitui such snd on a.counrofresrictions imposed by varlousAc6 and Rutes.

The KeBia Con$dalion ofPoddy Ldd dd Wertod Acr, 2008 sd Rut€s dsde theGunder Nhich was enacred for consedarjon of paddy ldd and werlands of Keraia imposes rcsticrions in miningofordinary ssds occurinB in wetiands and paddy fi.tds. The said Acr and Rules ft inpl@ented by Revenue Depanmenr ln addirion, covernne.t have srup Disticr Expen Conmin€e to monitoraod @ntrollne minins activnies olordinary end. In Ke.ala MinorMinedl Concesion Rules 2015, it h mmdated rnat No Objeiion Cenificare ftom thc Distlict Collector concemed, baed on rhe r@nmenddion of$e Disrict Expen

C;mminee onstituied by $ecovennent in.his regard, is ro be pr.duced by $e applic$r n the @ of .pplication for draction ofordinsysnd.ln addnion, Bdnk gmrb€e lmm

.Dy Nalionalizen or Scheduled Bek !t rhe rale of Rs. j00 (RLpees rhree hundred ontyl per cubic merre tbr the pueose of Ml;3don olpns diar wijlb€ tomed aner quarying in $e arQ l)emined, in6pectofapplicarion ibr ext@tion of odindy sand. The m itring o I oilinary sdd liom Flaeo-chmneh aho cde some e S nce sand is a sood aquiler, the mi.ing ofaquitar syftm poses threar to sound waler rvailabilirl in rumundine !16 l-lowever in cenain cases, the minins ofsuch sed ftom paddy lsds increN€ lhe produciv4 of paddy 6 exkss sand h rne paddy lands are nor

In Keml4 due to shorlage ofriver sod and ordindy sdd oeudi.g in pata@{hdne1s, de con$rucrron ndsrrr now ss manufsclured sand obtainsd bycrushingofcrysbtlinerftks. It miy be nored lhatsinc€rh€ Reventre DeplnBcnr is lakirg care ofrtt typ$otniDing rctnjti6 rel.t€d ro .iv€r srnd lnd since sand auditing.nd orh€r stldiq r.e carried out u0der ihe &gis olthe Rev.nue D€parrmenr! this repori sh l not be used lor tne PurpNe orobtaining prior environhentll cl€aone ior mining ol river sand,

Larerrc E a soiland rock 1), e dch in iron and ahrminiun. dd is commonly considerd ro halc fomed in hot ud wer ropicat ares. Nearty att taFrnes & of rusryied mloBrion. bcca& ofhish non oxide coment. They develop by inlensive 3nd LongJaning weathering ofthe underlying pa.ent rock TroFi.al wearhering G a proloneed proces ol chemical w$theritrs which podlc6 a wide v.riety in the rhickness. Srane chemistry and ore Tne mljorirv of the land @ conbiring lat'riEs be|mn ninemlogy of th€ sulting soih 's the topics ofCancersd capricorn. rosn Angadipum Laterie is a Nalional G€olosical Monumenl idenrified in Angrdrpu@ tr wN in Malappumm disticr. The sp€ial signincu@ of AngadiPurm b laErites h that gave accoufl ol here thar Dr. f6nois Buchnan-Hdilron, a professional surseon the fi6r $is rcck NT€, in his epon of 1807, s "indurated clav ' ideauv suited for buildine cod$ructidn. This fomation falls ouhid€ the g€ne6l clasification of ocks ndclv, rhe ilneous, neamolphic, or sedimenEry rocks but is an exdlusivelv sedinenEry €idual wa fitsl coined producr'. h has a generally Fined and polous apteMnce The nme laErile in lndia, by Buchdm and ils elyFology is lEced to the bin word letnis" L\ar m*ns

bricks. This ex€ptional fomalion is found above plrent rock rvpesollariouscompoil'on namely. chamockne, bplynne. anonhosne and gabb.o in Kerala 1he ialetite prolilcs in diffcrerrtyp€sofocksvsi6dependingon thecomposirion ofparentrock Forextnple in Chemockites.thefticknessofineprofileaneesfrom2mtol0rnwnhhumuszoneonrhe top with lhin pebbly zone (wirh ieftuginous pellets in clalev matrix) unde'lain bt qnh ve@lculd laterne with tubularclviries ofvdious shapesand size filled kooll'iric clav' 'lhis is lolLowcd by ihin layer ol hhonarge. Funher below dmpletelv wdher'd, paftlv \rearhcred or liesh parcnr rock @cur In some places one can see hard dunciusr at $e top lhe nideralogical siudy oi latcrites releals that all the silicate mine€ls have been tmnbmed to a minue of g@thit€. hed ne ond kaoliniie in lalerile samples deleloped ove.chirnockite Funherstudies reY€l€dfialpvroxeneshave beenlllered b goethitethile Monuile a'd |eldspa6 care riero kaolinit€ QMnz is cBcked, eroded dd disintegrated Zi.cons aE found d accesory nrn.rals Larerne aid bauxiteshow! tendencyto occuttogether' Aluminous larerires and femginous g6duaLlv biuxires are qune common Themo$comdon irnpurit] in both issilica Lar€rire pasesintobauxit€qithdeoedcinimnoxideandinceeinrhrminiumoxideTheiareriie n: (i) deposits may be described on the bsis of$e domimm exlracrabLe mineah in latcnre alunidous hErite (bdxna, (ii) feduginous lsterite (non ore), (iii) nanganiferous {m$ernseore), (t) nickeliiercusladne (nickelofe)and (vl chfodirerous latente(chrome I ore). Laierire wid Fe2Ol:Al2olario more than one, and SiO2:Fe2Ol mtio less rhsn ll and is temed 6 feruginous lat€rite,while thal haline Fe2Ol:AL2Oi mtio Less rhan one SiO2:Al2O3 6lio le$ than l.li is iermed d aluminous lalerite. LaErne cd be considered aspolyneiallicoleasirisnotoilylheessenrialrepositorvforaluminiud buiahoasource of irctr, man$nes,nickel and chonitro Fufrhemore, it G $e home for eml tace elemenb like sallium and vanadium which *n be extacten as by-producrs. I. Ke.ala lacrjtes !re cxriacted as building sbnes which oF usei for conshciion ol building Larente 6 a building stone po$esses one ldvanhge that ir h toi when quaflien sd can be *sily cutdd dEsed into blocks md bricks which on exposure to sirb€cone hard. In addition, laierite (aluminous laErne) js extraded lor industrial puao*s (ior eg. cemenr indusrry). Io addnion lo aluminous lalenG, bauxiles are llso mined in Kemla.

Ilence,whilesrdringmjneBlconession for lElefiie n is nece$ary tocar.yourrhechemical analysis to e$ablish snrether the mineBl is bauxite or aldminous lateriie l-ateite,ihemainconsnudionmarrialoftheare!,hdaverylidedisnjbution.Iiisquonied in re iom ofla.ge bricks md is used in buildine constuction. The basenen @ks at also g. od.ou(e ol!o.q'L. ion mare-:al r2.2.s Grinite Dinensjon sione and cranite (buirdincsrohe) For administrative puqose lhe hard cr]sralline .ocks rhich do nor hale ant economic minemh se cldsified 6 gmiledimension srones and granne (buildin8 $ones) The definiaon given in the Kerala Minor Mineral Conce$ion Rules 2015 is as followsl

'Cranitc dimension stones include alltypes oigranires, doLeile.chamockite,leptlnit€ and

.drer clvstllline mcks ofAcid, lnremediaE, b6ic and uhra basic sroups oliCneous and metamorphicorigin lvhich ft suitable for cuninE to pre-deremined sizes, polishing,cding and amenable for naking vllue-added produc6 in decor{ive monumentil od ornomenEl fields of iiduslry as a high-ulle ited. Cranile (buiiding srone) include all rhose sDup ol Fcks specified above which & not suibble for using as dimension slones s specified therein, bur can be used d ordinsry building slones, rold metal. fubble and ballans after h.eakiir-g inb nregularpises by bla$ing or otheMke s Loq valrc nem. The Rules insists

rEr rh. mcks hcving the qualitt ofgreiie dim€nsion sone shall nar be qus.ied for gGnite

building none as $ese two types of mcks have differenr laluesrroyalriel.

lhe major greite dimension $one belt of Kerah can be clssified by its g@logic Fning

chadockite-Khondahe beh (mlour mnges frcm paLe ereen with mo$led red. bluish green wirhcordierile, deep dark ercen, grerish whne). Tfle innusive or anarecric sanires and a$ociaied niena es ol PioErozoic age (colour: Pink,ljBhr pinl Gray, yellowhh whitedd blukh pink Rilh wavy padent. Dolerne-Cabbo dyk6, Protsobic inlrusire hypabsal dyke swams (colour: dark sreenish blue, bhck and ddk gEy with black spo6).

I ln Enalolm disEic! $ough Chdockite is p6enen! tne se is nd min€d s dinension stone 6 it is not suitable on &count ofjoinb md hairline cBcks. Oc4ionally, leucosabbro is mined in ene pl@s for naline paving stones.

AllArched ud Poltro&ic Mks ofKeBia Geler serion on CologJ ofKersla) which ee rcl listed above as emne dimension sone falls under d; caiegory of g€nne Ouildiig srone) dd are found below ordinsy eanltlarerilevand oder edinal!ry @ks. In some caes such ocks are *posed as hiilocks wnhouiany ovefburden. t3 Details ofminor mineral concessions

Pemhsion for mining will be gmmed on cse ro 6s b6is oi se.taininsrhe availdbility ar the lte md only if conditions sipulared in $e KMMC Rules 2015 orc srisfied (The reader fray refer th€ KMMC RuJes 2015 available in rhe websire w*wdnskeErasov.in lor moEderaih in this regard) The concesion wiltbe Cranred onl] ifolher sarurory ticenses like Dnvironnenral Cl€mce, Explosive Licence. consent ro opeFre issued by Slale Pollurion Contml Bodd, NOC is;ed by Relenue Depannen {6 fie d$ hay be),

Dan eemus dd O fTeruive T6de Licen ce issued br Local Self Coveh ment I nslirutio is, N O C related lo Co6tsl Regularion Zone (as rhe case m.)i be)j NoC issued by Fores (s the cs ma! be) etc.Themineml corcesion willnor b€ granred in theecoloeicatty sensitiveaEs, ccologl.dl faeiLe zotres erc. a

= inp/{w @i:r,gsi pv idgiDcts . r tuja, r N 4d 6ir x!nu, P r{g.a'c@lo3j6rs!rylyorJndhMk

r. *w.dhe.keFlo.gov.in 6. wl kercn!is.(ic.in 7. rra.keELsoih gov.in

*id (o"r3sre t, aME t G.das alxaoto

Geology ofKerala

Physiographiqlly lhe sbtc ca be divided inro lour domains frofr €Nr to wes! viz., lhe Wesren Chat! the foorhills,lbe midl&d dd lhe oasul low- land,

lhc hilirrges olde Wesren Chats rise ro d alritude ofover2500m rbole th€ MSL ad rhe cE$

or the mCes hslks the inter stare boundary in mos of $e pl&es A b@cn in fte continuilt or $e

ranges marks rhe Palghlt Cap with a sinisralshift of50 km beNeen tne shined cresls. The Wynad

plaleau and de Munnd(1005?'00":77.31'00') uplod lallwithrn th6 ane.

The ioofiills oflh. western 6has comprise rhe rccky arca ftom 200 to 600m.abo* MSL. h k a tmnsilional &ne between lie hish.6nges lid 6'dland.

nris iorms m aa of gendy undulating lopogEphy wid hillocls rd dounds. Lale te cappins is .ommonly noticeable on the rop of thes hillocks. The ow, na.bpp.d hill@ks fomingthe laFrne plaE u .ange inaititode Fom 30-200m and are obsered beNeed coastal lowr.nd dd $e loolhilk

Co$tal loR-land is idenrlned wirh attuviatptaini, sandr stretches. ab.aded platfoms, be&h.idges, raBedbeaches.lagoonsandesueiesThelow-landandrhepiainsaregencrailyless!hanl0mab.ve NlsL.

KemLa is dralned by 44 rive6. many ofwhioh ofginat€ ftom rh. Wesrem Ghlrs. Exe Kabini, BhavaniEnd Pmbar which d€ @t - fowiig, rhe esr ol riveu ft west- nowingandjoin rheAobian Sea. A lew of them d6in into the backwareE. Most imponant rire6 iwlh rh.n lengrh in km in paranthesis) ofthe state, aE Chandneni(105), Valapatnn (110), Achankovil(120) Kalllda {l2l),

vuvaauptrzha{121), Chalakud} (ll0), Kadalundi(130), Cha iyar (169), Pampa ( 176),Bhs!$apuzha Corogislly. K€mlo is Ncupied by Prscambdun crysrallines. acid lo uhm basic inlrusiles of Archaean ro Prcleroaic ase. Tenisy (Mio-Plioenel edinenrary rccks and Quatema!- sedrments of Uuvial and marine origin (Fie l). Borh the crysbllines and rhe Teni8ry sediments htve been

Bed on rhe debiled srudies by cSI dtrring the las rhree dcc.des, the follonins straiigmphic sequeice hs been suSa€$ed. au@.!y(a) !i!--uF9raroD(66r''d) &Enstr!!,i4u&o !!r. t[}Plioe!!Orr) G.d.rrT9 (sd@ d dy d

M$ozoi. or_r{vl)

P YNgd sdia, l,jl:!'8,|.!'!itqGqh'g:!dfurd

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TheArch!ears

Rockr ofArcheln Eraencompsawidespecnamoflido-ssenbtages regins ftom knondalite, chamockne, Cneiss dd neE{edinentory ocks o@upying the We$em chals inctuding tne foothill region. The Khondatir dd Chmockire Croup ae orEta€d *ith rhe Estern Ohar SlpeBmup bed on the oveEll siditeity in tithology &d g@nonorogy.

The mera senihentary, and uhramafic rocks occutrins n rhe Wynd Dkiiicr Cene.Ered keen ahonc the CSI geotogisls 'ntere$ in tg?Os. The high,srad. Wynad supdcrustat mcls are corclared wnh rhe Sargur Schis! CompJex ofthe Kanataka Oan, er 21, t9?5iAdiga. t980) Tte vdEtose rocks e cbeacrerised 6y inrense detomarion. medium ro high_gE!€ meranorphtsm, migmadsarion and lack of sedimenrary srrucr$es. The schtsr compiex coisisls of meE- ulldhafiEs. schis! mera-pein s, meE-pyro\enite. serpen nile, ktc-remotite rcck and

Thsmeh-sedinenbrieso@ur6thin linearbodi€s wirnio the migm€rites. Th€se ensisl ofpetires, psmnopentes and qulnzites. The predoojnant rock types are cotundum_ mica $hht, kyaniF sch$, quarE, m'a schist ed non sone.(Anij K umar er "t,l99t).

n.r.i Kebri ,31 "de 1 These rmks ocur a neow eute belB, lenes, md other foms ot enctaves within peninsular gneses md chmockite_ goup Th. @ be divided into nedium-ro tow_ Brode netasedimdbr! ocks ond met!-m!fic tud m€t!-ulr.amafic rocks. Theljrhotog, ofthe hiSn_gnd. shisrs comisr ol quarE-mica schht *irh kyanire, quartz-s€ricirc schh6,qudzn€s,ms$etite quonzne, tuchsire quatune ed mera-utEmafiles l'heir conllcl wnh rhe suFounling gneisses are concodsm due to larerco-lolding Sevehllinearbetlrofsuch high-gnde schistsand utlrmofire enctav* occur 6 Nolared bdds vi&in the granulire md gneissic rermin ofKdaEgod ed Kenurdisnicts.

Layer.d ulimbNic basic cosptex

Rennanls ol ldyered bdic- uibbdic compjer m reponed rrcm Aeppadi aH(Nambiar

I 9321.The ult@afi cs are rcpresen red by m e$-pyro xen iF, m.tar.lo terire, peridoiite wnh ch rom ile and meh gsbbrc (Lshili ?r a/, 1975), The anonhosire ofAnappadt is onty a few m.c dick. O*utr ces m eund \snrl\^u. p,dur Md vetnuti&e& enecrrsrmnaing,mo^ lemiclld b.dy of*Fentinised dunire is Eponed from punath mica mm. beh.

A nlnor body (200 n long ed to-ljm wide) ofsonhosite w6 feponed wilhin pyrox.ne-

Eran0lne-chdn@kire l@dn from Kdlmjai pzrau r, of Kssgod dislrid (AdjCa, I 979).

f4RedrsFbi3, t A.other dismembeEd layeEd igneous compld conshling of allmal€ ltve6 of p.ridotite and pymxenne within chmockit vs tEced mund Pmathadi dea ol Kannlr Disti4 (Adiga l98O).

Perinsular On.isic CoDplex- r OOC I)

TherocksofPeninsularGneisic Complex(Pcc) are exFosld in rhe noirhen pans olKeFla idjoinins Kamabla Thh consks oia hete.ogen@us mixrur€ olgditoid maierith' The equivalcnr rocks of PGC in Kerala include hornbleide_biotire sneiss GhearcO biorne- hdmblende gneiss, foliated grsilemdpinlsranite gdeiss. Clanite gnehs is cxt sedalongthe inra-Sr$e boundary ol Palakl

Thk consis$ of gn€isss showins pi€pond€Ence of either homblende or biotne The percenbge of bonblcnd. dd biotire rdries from plrce to place. This cm be tstced ton Manantoddy ro tufther nofthwest upro the wesi coast Wesi of Mdantoddy, tle ock s homblende Cnehs. tl slows corle gmulilic lo gneissic te{ure and is conposen of hornblende, feldspar, quaiz, pyroxene. biotirc and sahel Alkali lcldspar shows altealloi to . c\ dld *'.J.e B or:k is ra lir.d orddr a'ier 5on bleld

Atuund Mahe dd Thalasseri, the biolne gneisscNan er,l 1974) is medium_grained lnd

sndisose rcck conshting olahernare layes olmsfi cs and tikLcs

'lhe KhondaLite C@up of mcks incLude calc_gmnuLi!.s. quaitzireand paB gneisses ofpeliric

pad age. Pam-gneissesdeubiquitausand arewell_developed in !hesourhern pan otthenac.

panicuhn!. in Thnuvananlhaprram tnd Kollam disricG Calc-gmntrine and quadzite occur

as bands \rnhin the para-srehses and amidi the charnockire Coup and misnatitic Snerses

Calc-sanulite occu6 as lined bands nainly ii the eslen pan of Kollam and ThiruvaianthapuFm Distric! nonhest sd ea$ ofMunnar in ldukli dislrict dd in plns of P;Lakkad Dhtrict. The rock is generally mediunr ro coa6e-Crained, inequig€nuldr and granoblanic in rexture. lt co.sists or diopside ddd plagioclase ltliie,als like wollasroniE, scapolit, calcne, gdmeL, spinel, sphene- quanz and apalnc are also pfese in diiLrenl Q!en. occu6 a linear beds dnidsr the knondalitic $eiss, chamockite dd miamatitrc gneisscs. Thee bands ft exposed berween Pathananhina P"1545: 76'4700 ), ud Muva$upuzna (9'5900 : 76"3500 ) in Erna|1lam Dkricr. The mck is coese-gdined and sene€Jly whne in color qnh a broMish coaling on lhe weathered surf&e. lr co$kts oi gd u aroraro si$.dbo dicare led,p!,Cmd dd nonoride

eo dildow bid e-nuirunile gneks

Ceneritlmus biorite- sillindite gnei$ is well-deveioped in fie soudem p?n of$e sl!t.lt

occurs in closessociation with the migdltiticgneisses, chamockilesd cham@kne Sneisss,

mostly a wstheEd outfops. Sillimanire- rich bands occur altemaling with Samet - nch ponionsoiwid qlarEo-ieldsparhic l.ye6. Ruiileand ion oxides de th€ common ac@sry

Charnockire Cmup 5hows greai diveGity in lirhology comprisinS pyroxene glanulire,

hombiende plroxenile, naFretic quaruile, charnockne and hypersheneniopside 8l'e6ses and codierne Oeiss. ChmNkne sd chamocknic gneiss have preponde€n@ orer allother cr!$lline.ocks overing 40 -50% olrhe rora cre ofthe State. The chsnocknes 8re weLl- erposd in the cental hd nonhern parts oi Kerala including the high-hills offie westem Chats. Che nockite h6 lesser predomin&ce in Tniruwnanthapusm and Kollm districts. ln

Attappady, rhe Bhavani Shesr Zo ne is limited by the chanockire frdsiiofihc Nileniplareau on de north. Tlrough rte iiterelationship of$e Chmockile and rhe Knondalite is not clear, in many pla@s there ar€ inrerelarions mlher thm inrerlatering ofone with ihe o$er, In Palakkad Districl.lhe Khondahe croup of rocks sruauFll, overlie the ch@ockne The occffience ol pyroxene crandn€ 6 fine and liner bodies whnin rhe cnarnockne ofTrur, sugges$ fiat chmockire isaproductofhiCnatisarion ofpyrcxenesrdnuliteividldhaan and

Sukumam, 1978). Chmockile aid chmocknic gneissconsh!ofquan2,leldspdmd bioliie camet-beariig variants ft al$ obsefred. lhe b$ic chadockik h more gmnulnic ed

codoins clino- and onho- pyoxenes, feldspar, biotite and eamet wheFs the acid varie'y {ahskite/ enddbite) is g@nish blsck, coasegBined. mdsive ro pmny foliared rock consislins of quatu, feldspd snd plro:eies. Basic chamockne has low po&sh leldspd dd mo.e clinoprloxene. This is devoid of sanel dd giaphne, but shows a linle amounr 01 biotite(Chacko 1922). Due to lhe polygeneric nalure of lhe rocl, geochenr€l and

I mheElogicat vdiations do exisr hetren charnockir6 Eponed nom Ke€la. tn rhe pe.ite varrey r€g'onj in tdukli ed Koiayan distic6, pyroxenne and atskire consirlre rhe Chamockire coup Oan, and Sellan, t9?6).

The alailabte age dara i.diane thal fie 66sive oham@ki tes arc old€r and d'i' ae$ @se b.rw*n 2 | 55 and 2930 50 rt Ma (som& , r 997). aho chdftkit€ h$ been subjeded to Etb$essioi od oignalisation. Ahniqn lo Pllr€o-prolerobi.

A sucFs'on ofehisroe ocks in pansof re|icherybht n Kannurdnrricr isd6cribed6 vengad Cfoup otmcks CNair, t976). The vengad Croup comprises of bsat conglonekre, quin/ "ard qrMz-nna nt n t\e. orL.Lar hr,t- sadd.ol3 Ire.onslomemr\ ino!. g'aded bedding ed quareire shows cunei.beddjde

An osular unco.fomiry marked by;onetomerare hoizon exlendrig riom Kudrupardba ,l4 (ll'49 10": 75 OO io vengad (jlo5j,t0,,:75 ,32,00,,) ) ,n Klnnu! djsricr, sepaaks.he youiger quanz,mica schisi sd quanzire from the older e06rose md gbeisic iocks. Tne hhobg' conskts ofbet otiComicriccongtomeBle, qu!tuite, qu@_brotlle-musvjt€ schhr and bioijte quaflzire. T1E schhrs aE exposed over an area or 3Ol] sq kn having a tensoidal shape wirh iB longer ah rending :n NW SE diEction. T migfraritlc wilh reticts of high-g,"r.,"r,,,r,,,,*."r," "J:,T:X:;:: ;rilil,: Compler Four hajor dcurcnes of constohede are noliced In a Nw,SE direction overa rdck ofmjsmarisalion. presen ce o f p.imary sru clures aDd tow-eede nebno|phic ninerals lIignrtile\ Cneiss\ cmniroid ("CClt)

Qua.rzo-retdsp hic gheiss

Migmatite lncludesva.ietyofCneissicrocks which nexl ae in rmportance lo cham@kire 6 3 doniinsr litho-assenbtage. elsrt&,fetdspa6ic sneiss @curnds atone $e contacr 2one beFveen game.biotite gneiss and e@et-sjtjimanile I,eiss of Thiruvanlnthapum srea representsanoriginatintrusivephase.ltisafeebtyfotiaEd,,jne-Crained,leuoocericgmuliric

(e,:ran:te $nc 135 I rookoccudinginclo*4eciationwirheahetsitti(snilegneissandemel,biorireCn.nswirh

E adltional contact relarionshiD in th€ southed panr of Kemla. The o.iein of $is @k is atu'bLted ro $6,induc€d injerion ofscid mataiats idto tne hos rak(NlgeswM Rro od

carn€r biodre greis

Carnelbiode gneks is we -developed in lhe nonheasrem pa6 ot Ko[m md ThiruvMtuthapurmdhtrics.Thiscariesinclusionsofpyroxenesranutiteonddisseminotions

or plphiE ar many ptaces (Jacob. t96j) tr consisrs of quan:, micropenhne, biofie, plagjoclass dd sEphne. This ock atso occu.s in fie rcnhem pafs of paraklad Disrict in close 6sociation with knondatire, chamockite sd hohbLende gneiss. These rocks de sub*quenrly fomed by r€uoer$sion and migmdkarioi of the Knondalite Crcup.

La$ oi Kottaym dd Idukkidhtricrs, tighr Cret. pinkglmelbe.ring biorire gneiss is widely seen. Il n a e.eissic gbulile. lhe pr€sence ofbiorire dd concen nion of gder jn trfe.s g've the rock a bdded appestuce.(Cst. r995).

Hbrnblende g@iss, horDblede-biotile greiss, quan? n jcr gtreiss

These rock lyps o6ur wi$in the migmarnes aid aseciated retrogqded chanockire. The nan'ns is purely b6ed on $e pr€pondeGnce of the nin€mh dd thes rccks @cur in the

Perila. valley @ esl of Tlodupuzha.Nan and Setvan,tg?6). Thee nediun-Cdned , tbliated, bnded rccks consist ofat€mate taye6 nch in honbrende orbiotite. aods ofco&se

ro mcdLufr'srained lighrSE, to pink Smnite rave6e rhese rocks. Hombtende bjotitegneiss showing litpdlitrelarionship with rnegBnnesneisses nrhedohind!rcckrype inrhe pedrlf \!lei- This is admired wnh contoned bands and enctaves of pyroxsne effulire, calc- jghty sranulire od h06blende- biotile cEnu|ne. These ar h defomed.

ln the Palaklad gap ae, thesegneis*s occurovera ldge aEa. showins migmarilic nrudures

s$h as lgnatit€s, nebulites, schlierens, pty8naric folds, quanzo-ietdspathic neosohes dnd

fenomagesian palaeosones.(Mu6teedharan and Raman, t989).

B6ic dj,te enplahents wi6in lne Archun crystalline ocks of KeBta @ spreld thrcughoul the mtirc length .nd bredth ofthe srsle. Oflhesq ,joterile dyke occuring norrh of rhe Pllakkad gap had given Polerozojc agc wher*s in th€ south this dyke h oiphaneroaic

ru Rech\orc I r. I ase. The oldtr 6aic dyles e dehorphosed alons wilh lie ountry ro.Ls dd @ now remSnked s epidiorir dd mphibolir. Another set ofdykes, appmndy tost-daring the regional metamorphic evflr de subjeded to rhema! meirmorphish. Cloldin8 nd sericitistion of fel&pas ed uElitisatlo. of pyrcxenes ee 6mmon in such dykes. h th€ .bsencc oi chronologiel dat! such dykes are considercd io be ol Proteozoic 33e- Mosl of rhe dykes are vedical in disposition md a.e taced a linear tiatures. t,-e.r.td' panem df sone dykc swarms srggsB thd maBmalic inrrusion vs contoiled by shearing of the host rock., Minedlogiolly, the dykes aE made up moslly orplagioclde leldspe md pymxene(augle and&Cnine-ausite)wnhmagnetne.apatiiesndolivine6&essories.TheENE-WSWdolerite dyke swm ofAsali Anaklari d€a in Palaklad Disnid qilhin the Bbalni Shear zone

lhowed in ieropic age frcm l9()(l to 20O(] Ma {Radhalaishna and Marh€w Josph, l99l). The rock is hidly joincd ed altsed (Jacob, 1965) Siniln basic inrisive bodieseetnced in the Achsnkovil shed zone in vdhmunm (9'1400:76'4640 ), Ktrlekhda pefia! (9'1600":?6"4745 ) (Thoo6 Marhoi e/ al, 1934). Sh€llike bodies ol nne to nedium gnined, ddk colouEd nela Fbbra occuN in Periyanuli(l I'13 00';76"43'00") for about 20

kn in ENE-WSW di@rion. Kaoladiil l'0400 r 7601230 ) and lew gsbbro bodies south of Thuupanu (11!06'30 i 76'4445 ) in Anapady valley, Palakkad disrl Mera-Eabbrc foms snall hillocks 6! of Payyanm (10'3100 i 76'2100 ). sourhwss of Ksinur (10o3600": 76'0900).ndchemnannur{10'4100"i76'0100).vdga(10"3500"j76q0600)mdAnhar (!0'1700"i76'03'00 )inTnchurDhricr(Makdevan, 1962).

blkes in nonh KeEla show , NW-SE. NE SW and NNW-SSE rends. Ho$ dks are charnockne, gneisses and supmcru$als(l.adhakishna e,,l l99l). Dlkes ae mainLy dolerite but occasional meta Fbbro or meta-norite dre also l6ced. ln AgaLi- Anaikani area oflhe Atapadi- Bhavani she& zone, dykes aE confined wilhin a 20-25kn wide zone &d extend from *esr ol Agali lo sNard for abour l00kn lollowing a ENE wSW diHrion.(Radhalishna s/a/, 1999).

Th. rockconsisB of95oZ alcic plaeioclde,5%clinopyrcxenes and subordinate amounis ot magnertc. There are a number ofconcordant and discordani basic i rusive oi dole.iie 3nd

$bbrc.meta-eabbrc, mera norne, freta pyoxenite and anonhosilic Cabbro. These arc not hdop,ble &d are *e1 oapprrpra irl00620 t6o0r(6 \eLlrllo0400.76o0_454 'n

Disti.tsurvey R.po( ErnakuDn D srn. (*:l? sr*e KdDtu ( I r& 12":?6005 32). An exiensiv€ basic diorile has ben mlppei over an @a or 25 sq kn al Paavalli (l l'53 30 ,76.2'10 ;N!n, e, ol 1976). 'lhe rock is composen p€dominonny ol calcic plasioclasc (95./o) rest clinopyroxene wid subord'nate mount of magnerite. Anorhef relativelt small body ol flodhdiE is tuound Kalivdlli(11"5130 ;760t230 )insouliWynadbtuk,WlnadDistlict

U|(r!brsic/ blsic intrusjve 6,0unge.)

A majorellipticalbody of oonhosire spread over an !rea ofmore rhan 50 sq,km is Eponed tromPerinrhafia(1201000:7501?,3Oividyadha6nerdl,19?7).Theaionhosireiswirhavery

iiegu ar boder and I longue-like prcjection inro lnecounty rockotchamockireand pyoxene gnnulite of Khnu! Dhric.The anonhosite G co{se to very c6dse Cnined, and shows variarions 6om pure ffonhosire 10 gabbrcic donhosir and sabbrc trom rhc enft€ ro fie penp hery suggesi ve of rcn ing. The :n odsl com positjon co responds ro near ty 95% ptagioc tase (Atr < i&r) $d l07o clinopyloxene. apatite, calcne dd nagnerne. The 8albmic variob have

Thesructuml confisuration susse$s tharthe anodhasire w6 emptaced in synfomal $ructure 3s d phacolith. The flov-banding in anonhosire indicdes irs syntecronic emptacemenr The

Perinthae anodhosne is dsigned a proreozoic ase

€zhimrl! Cnbb.o granopbyr€ conplex

The major highielief fearuc Froxinat to lhe Pefinrhafta anonhosite n consrituted by $e gabbro glEnophye Complex (Nairand Vidyadhatr, 1932). Tne Branophyre masifis fringed by lhe gabbro to the 6r and south. TheBalatjfaulrrunninsnonh otdeomptex ispreslned lo Mle dismenb.Ed the body frcm the Perinrhana donhosite. Localty, the sabbro has anorthosiric dilierentiates wilhin ir. vcins ofCranophlte l6veEe rhe gabbro ar ptac6 give rise ro breccia'like structuB. The g€nophyE shos a sharp e ad wnh rhe gabbro irto which h Lntiudes. Rapa{ivi slructure is obsered within the Sranophre According ro Nan and Vidyddharan (1982) rooks ofEzhimala complex display bino&t characrd Nirh conspic0ous bdic aDd s lrcic componehc.

Kanikalan and KdnasA cabbru

Tw. Babbro bodies ndely Kanikullm sabbrc and Kamus gabbro are tocded nonhea$ of Manartodd_r borde nB the Kamauk! (Nair e/ dl. t975).The gabbro bodt ar tunikulam o@upies u 6ea ol about 45 sq.km. with d ellipricl shape wirhin the gneissjc terlin. The acrualconlact {ilh the gneks is conealed bur il isbelieved to be shaip. Ar 6d! ptaes, rhe Sabbo is aAistis'l by 63M quarlzo,fetdspafiic marerial.

The gabbo is @e-g6ined and of uncv.n rexr!re consisring es*nria y oiptlgioclde lnd ptoxene. Veiadon b anonhcltic composition is noticed. Theplagiocte is of tahrodorne composnion bd shows alredtion to sericne at pla@s (Rema wdier dd venkallsman, 1986). The p'rcxenes aE umlilised lo larying degres.

Tne Kamug gabb.o body is lo@ted elsl ofir sd southof$eKabini Riv€r. h shows simite featur€s as that ofnhe KaftitulM sabbro. The r@k shows phenocry$s of fetdspr set in a fine

Ar Addktalhodu( l2q3 l'3s :75"1025 ), northwest ofMananroddy, s 8 kn tong mera-gabbm, isiitusiveintothcbdenenrgnehsesonrhreesidesandrhewynadschistsintheed lroccuu proxinalto the Bovalifault/linegFent.lrenclosesj parchesofquanz sedcite schhK and bioine gneiss. CNair e/ al. 19751, The rock k meecraric ro metanocrcric. medjun ro.os6e gdined connstrnsmainlyofpyroxene&dplagiocLse.Thercckshowssub-ophiticlexruresdensists ofeDslariteedinlemediatepldgioclaseofandesine-LabrodorireomposnionNansr,ll9?6). while rhe esbbm bodies of Kdikulam and Kamus ro rhe esr are olivine- bqrine, rhe Adakkarhodu gabbrc is ensurite- bearing. Olivine, augite and zoned tetdsplN are r*orded liom the e6tem body B,iile rhe westeh body is ensbtite, besing, wnhout lhe zoning in

An extensiveb6ic diorite body (25 sq.km.) h6 been incd norlh ofMananraddy in rhe Beeur Reserve FoEn (Nah, er al, t976). tr exrnds tilm Thnuneth b the Kamaraka srare border -fhe suthem ontact is with augen gnekses indiclring emplacemeit atong shearzones while n'dior'hern one wirh siltimanire sneisses. Aplheand doterne veinsareseen !d!esingtherock rnorlr_ pa.allel b de agionalrbliatioi. The mck is mesocarictomelan@raric, coa6e-Cmined &d consk6 olpink to gey feldspar, hornblende and bioriE

The rock is feebly gneissic and at ptaces po.phtriric (Rema Weier and VenkstsBnana, 1986).Tnephenocrystsaretoostlyplagioclase MaUcs ar tifres swerye buno ne pnenocryss

srrr K$rasbte 13, silinsrisetoauaen sttucrur€. Homblende is.lteredrobiorik andchbnre.Ac6sones include epidore. apatite, zoisire ud opaques.

Thedioire sh ows rholei il ic chete.istics 'The dio.ire h considered 6 a trdsitionat rck from rhe gabbo with whioh it is spatiatty dsociated in the nqlby dea *ith th€ pragj@le beo6e

lhe srca eurh of Palatkad exposes chamockire over tlr8e areas The chamockiies aft teprcserred by acid micope.lhiricchmockiteod intemediaregnehsicchamockireocc0ring in a$ociation with ganetiferous biotite gnets and khondatitc (NaEyanaswamy and puma Lakshmi. 196?). Mdsive chm@kirs are devetoped on a ,ss,otra, mappable lilho-units (Raju and Copalakrnhnd. t9?2), around N€dumanSad. The mssile charnockites in majority oithe cases are acitl sd inremstjate in composilion The rock is med'um to co4e,srojned dd shows xenobtsric rexture h is composed ofquarq feLdspar, pyroxenes, smet dd g€phiL *id accesori€s tike biotire, zircon, apatte od monujre.

palches. Snall ldses or veins of ch;ockne ecu in the gieGss ol anphibohe f&ies in rne -ftnuvmothaplm ma o{ageswda Rao ud Raju. 1970). HeE, rhe incjpie.r chmockies afe rhoughtto have lomed by resfomation otpafagnei$es. (Hu*n er 4l, t987tS$bsh er ,r 1990). A few dohind laneties of incipienr chmockiles have bftn c,regorized b, Ravindra Kumartud Chacko (1986) on rhe b6k oftheir mode ofoccunene, dsciarion and oknrcaL processes Lnvolved in theif deletopment Ar Konavarofr, nonh of Tiiruleanrhapuram. $e charnockne conshrjne otquao. K-le dspar. ptagi@lN. brotn., garrer ind orthopyfoxene I essenriar dinerah and smphire, zircon. ilhenire, monzne. aparire. nrie and bagnetire as accesory mineras arc produc$ ofraistormarion ofgnenses rnro coaregmined chanocknes,tong a sysen ofconjusare fm.lures lnd toliarion ptanes. (sarirha and Sanlosh, 1996).

Cord'erile o' CharDockr€ Cn.N! cordiefiE beains laree linar zones otcham@kiles were repored around parhanmdiaa NagesvaG Rao and Jacob, 1967) dea Cordi€rire chahockites or orrhopyrcxene,gamet- cordierite bearins gneisses (Sinha Roy er dl, t984i Sorosh. r9B7) occur 6 disconrinuous bodies in lhe nonbm pais of Thnuvsanrhsputu ad in seJeded strelches ffrnher south a6und Koliakode.Ther@k is composed ofcord ierile. onhopyroxene, ptagioctase, K-ietdspd, rprnerand quanz sd a liftJeeaheldd biorne.

l40 I The gro*,lh of@rdiqite dd onhopFoxen look pl@ @ncomiirndy duing rhe onvenion of gneisses to chdocldt€s. At N€llikala in Palhodmrhitu, lhe ordi€rile een os onneddl grains or v&iable si4s in the chmockites (Nsdalud&. I996).

The gdites and i$ vdiets @cu! aound Chengannur in Alappuzha Md Parhanmrhitt! dktiicts, Munnar in tdukki Disr ct. Peralimala in Kannur districr ond Kelpent and Amhlavatal in Wynad District. M&y oithese ganites occur as later emplacemenh along crust.l liactures ahd fa0lts. The Achenkovil T.ndpami recronic zore, $e Atu adi sheq ane, Bavalisbed bn€ trd de Moyo sheozone de allmark€d by gtunlc empluments

Ihe Ambalavayal (l l'17'15"i 76 "03 10") cranire having an oval shaie cove6 an a€a of50 sq.kfr. The g6ite is light pink in colorand kcoinposed oiqualtz, pink feldspa!, homblende andbiorile The peematites tale6inC rhe gnnite showoccdional flakes olmolybdenite. The Anabalavayal gdile ecuninS in ttepoximiv ofthe Bavali lineafrenr is thought to be empLaced during its Emtivarion, The Ereit is int usiw into the homblende-bioiiie Cneiss (mignatite) antl th€ Wynad Supncru$ah (Anilkumar 4l 1993) Four rypes of gnnnes are "r record€d, viz.,roliated grdire, pinl smne. srey eraite and aplitic granle

lh.bliatedgnnneconsistsofquanz,microcline.oiihoclase,plaCioc!ase,biotne,hornblende, .hlorne. c.bne md ?i.con .The pink erMite is a fredium-grained consisting of quanz, nlcrccline. plasioclas, sedcne,chhrne, apatite. rutile,zncon and biorne The grelemnirek a hedium'to fine-Cmined rock conskring ofquanz, microcline. sericite. biotite. chlorite and

calciie.The aplitic granite G a very frne'g6ined frasiverockconsisring ofqudz micrccline,

o{hoclase, plagioclae, sericne, biorne, calcne, chlorire, apaa€ and opaques

K-Ar age ofAmbalalayal gffne (560i10 M..Nan, e/,1,1935) n loNerfib Rb-$ sge(595 :20m.a Santhosh er,l l986),burishigherrhdnfialofU-Pb-age(505120ma,Odom,l982l. The,redon for thk vdiation in th€ date may be altribuFd to the diferent rcchniques adopted

ddd aho ro rhe treseice ofbiotite ofmuliiple eenerarion.

IheMunnd(10'0500i77'0500)CrMitewilhana@lextenloit0sqknisdE-WireidinC ir.Cular body emplaced within rhe migmatite and apophyses exrend into the sudounding

gneisses. The CraniF dared to be 7401l0 m.y (Odoh, 19821is raveEed by peSmadle, aplit€ md quanz veins. Three tlT€s oiednire a€ re6rded. Foliared sranite, CoaM pini s.anite and nedium sre, ednire.The loliat€d cEnne onsists ol$rins.n dnd sbeai{r ofmafics @nsisrins olbiotite, homblende, ohlorire &dnagleriE altemating wirh lehics consisring ofqudz md poEsh feldspsr. PoEsh feldspor ispredodinMtty orlhoctae. The clos.ty spred tolifiionsee persislem bur disniinuols.This granite loms a dodal stru.ture sou$ ofMunnar ft has a shsQ conhct *i1h thc mignarire. Cotrse pink gnnire coisisls ofpink fcldspe, qudz and t linie lmounr oi mafics. M!fics are biorne, sphene add homblende Mediun gmiied grey

8€ntre, consist! ofquatui feldspar, biornc. chlorne. zlrcon, sphene, epjdore, calcile and

M,jor element dala ofMuhnar gdnites do nor show any significMl rariErion emonesl the three grlnrles. conlenr of ircn is moE in m€dium gey granite and tolhrd grmile. DiffeEnl variation rjilglms releala slighr rendency towards aLkalisanne. The fotiard sreircshows frore peruntage oforthocl4e than lhe oder rwo granires. (Nan and AnitKunar. t990) Ezhidda granopLyr - gmhite conptex

A prominenl gmoph)re body loms d; hillknown 6 Ezhinala. covering an ar€aof20sq km tumf Dhtricl. The gmnophyre is $sociaEd *ith gabbn and grdne and is mrnsed b) doe re dykcs. Two types olsranophyes have been decipheredrcaaree eiained teu@ratic one und medium - gmi.ed one {ith hore mafics. Drus) type. confined ro higher etevatjod conllin numerousvu8lineswith econdary oinedts tikequarrzsd catcire. RocksofEzhimala

C.mpLex dGplay bimodal chsacler with conspicuous basic and siticic componenu and roE lack ofrocks ofintemediatccohposirion typical ofanorogcnic suires CNajr and Vidyadhann, lr82). The eEnophyre is pink lo 6h grey coloured. massile, tine to coa$ grained. holocry$allino wnh equigtuuld rexiure. Theeranires arcol$o lypes The major tightpink sranne wilh le$ ofhafcs show siadolional Elarionships wirh lne more gEyhh poahyriric variant ( vsadon md venla6@d, I 976 ).

Cranoph j,rc shows at}!lel gnnophydc intergiov^h of quanz and feldspaf foming the ground ma$ wirh phenocrysts ofpotdh feldspar ud some zoned plagioclase T1€ groundmass is (olallvoio.lhoclase Augite isrhechieffedo-magnesium minemt Accelsories inctude aparire. sphcnc. epidore. calcite and maFelite. Texturally the rock shows v&jarion flom maree-

-qrained leucocdtic tr?es with less mafics in rhe southem ponion ofthe hilt and medium ro coa6e gmined rype bwsrds nonhem ps6 Minorourcropsofrspakiviexoiresarc rccoded wnhinrhe sxanophyEsofEzhinalacomp ex' Anonnosiles of Pe nthatla ud Kadannappally and Sraite. graoPhyre of Ezhinala loge$er fom $e Ezhinala Cohplex. The light pink eBnite wilh le$ mancs is the malor vanetv sholvins d gradarional elarionshipwilh lhe moregeyish Porpbt rnic veietv Thepoahvrnic vdiery, 3r pla6, shows rspakivi $ruduf. The poQhtrilic gr&ite shovs herled feldsptr mes&rysb Thisvrietyglddesinioporphyriricerdneswnhoutmddedleldspu&dathisher levek sFdes into gdnophyto.The granne contains 60% of onh@l@ leldspd, 5_10% of plagioclse. 20-25% of qu@ wnh a% of biorne, ePidore, magnerne 4d iluorit€ lhe 16! rne rocks a relarivel! minor molnt ofold€r si5lic inkid Sr '/ Sr * miio indicale thd hale mlcrial The Rb-Sr ag€ ofthe granophtre is eslimlred 1o be 678 m y Nanod Vidvadh!.an' l98l). The Ezhimala Complex lies it close proximily lo th€ Bavali lin*hent sussesting .d. \a. o1a o13 +e r eamel olJ 1r L ,or oir\' bod)

KolpatB((l lo36l5"i?6q(]5 li ) gmnire is an oval_shaped intusive into de Wvnad schsr 'he addcov.6odeaof44sqkn(Rloandvaradan, 1967) Thero.kisgreycoloued,medium graiired, hohogenous biofte ganite and has shaQ comacr si$ the @unq .Nk A lteble

tbLiation is impaned !o the gadire at plac6 by biotite flakes. Xenoliths ol amphiboine /

homblende gneGs are vkible ner the periphcry. Inegular veiis oipegmarne / apl'te tave6.

fie g.Miredd also $e cnclaves.The K-Ar ase dllhc biorite ftom rhe KalpatuSranne is dated as j12130 m.a {Nair€/,11985) and 527 m.a (CSl) Prcsence orenciaves ed absence of significmtrcplacementtexturesaloncwithlheCeochemicalchlFderisricsasisnaFagmaric p!.enkgetbr.heCmiie.Thepoxnnityoftheplutonroth.aataliLineamen!pobablvsugge$s

in!usion along rhis [!cture.

Th€e lypes olgdites such as coa*e grained biotne eBnile. fiie grajnod biofte gnnie, and porphyilic granileare mapped on $e bdisofrextuc. coiourand frode ofoccurence Coase The graLded cranire is a mdsive bluish gfey rock *nh large ienoblsb olquanz dd feldspaB 3cce$ories inc ude bioine, zircon, aparne ard sphctrc. Blascsis of leldspar and sphene d.

commotr. Micrccline, onhoclse, and plagiocle aN seen 6 rhe major feldspar. rlaeioclase .omposnion vaies tiod albne ro olisoclase. this iock is exposed in 'frikkaippena (rro3504:76{08 41 ), Manikkunnu (11015"41 :76i 0709), Kunamangallm fll!i0'08 :76007'll"J(Anilktrmderol 1993)

io3 Fine biotite-Brmne is a tine gBined msssive rcck erpoed !rcund Munilmala (7600633 il101706 ). lt @nsis6 ol odh@tae, quatu. nicrcctine, biotite, edch., zircon. sphene, apatiE md opaques. Mymekitic quanz is recorddt Pophyitic g6nne consiss of mymekitic qunz, [email protected], sncit€ dd biorire. very coase sEined biotit€ with inctuden crysblr of onh@ie, nicrccrine and albir arecomnon. Excepr tor rhe texru6, al lhe 6.ee srannes show sinjiech@lds. (AnirkMd, e/,/ 1993). B6ed on Rb,srdaling, Kalpana grMne r ,lared 765 Ma. (odon 1982).

Tne ChenCannur (9'1345"i 76.lt l)O") cGnite in pathanamrhina Disricr is an ovat shsped bodt with $e long axh Fendine in edlwesr dtection coverjng an arca of ts sq.kn in and around Chengadnur. The ennite is inilusive into lhe charn@kne snei$es. The body G empl&€d clos to the Achankovilsh€arzoie. K,Ar date otthe hornbtende indietes an ace of i50m.a(somane/a/, I98r).TheChengsnurgranireisinferedrobeapo$kjnenaticgtuire

Two qpes of gtun$ aE r€co.dJ. One is medium-gBiied pink gmnire Md the other is coaNe-gnined gEy granile. The fomer ansins of quanz. pe.lhiric feldspar. plasioctase. biorire, homblende. apatitc dd zncon. The conposjlon ofptagioclse vaies ftom rlbite ro oligoclas.. Microcline perrlite is also sen. The coae erained gre)r gtuiie consins of penhrte, plaeioclde, hombl€nde, biotite, quarE with occsional o@urence of hype$hene,apatite and zi@n Homblendeddbioriie aE tesscommon by ocuned hine€h rhan hypeAthene. Relicts of hypererhene de ltso seen. This gfdire hay be a poducl oi gannisarion ofchmockire. K:O contenr always exceeds rhat ofNazO . The high Sior.high alkali, h sh Fe/Mg rario, high values ofCaltium iddicaierhatrhe grtuire belongs roalkati t$e h.nighr have d origin nom recycled trd rehtdEled conrinendt ciusl (NajrsdAnil

ThePeralimala(11"09'19:75418,46")3lkal:eraniteisatinearintrusjvebodyempLacedatoig dredid lilce ofa nega foldin EW diEtion PeraLimla iniiusivebody occussadiahme ofalkali mnposition wi$ a ndimum lined exlension of l5 km and a llidrh of I km. Based on colour, €xture, mmposition and toode ofoccunsse fourtypesofCmites m identified. pink pinkalkati These de eneksic ginire, poFhyijtic ganir, gE saniteand pint Crdire. grad'te r a co@-Crained ock consisling of nicrccii.e, onhelde. ptagiocte, quarlz, hohblende, epidote, aesnine, sphene, calcic, penniF and apatite. Quortz is prenr in onl, subodinal€ momt' Feldspd @ dlis v..y hi8h. The pEfened orienblion oireldspff gives ! crude alignmenl. Ai P.onpunna, (75'44'00':l i'55'28 ) pink sneissic smniE sho*s preieftd orienradon of biolile dd p}Toxene. The poehyrnic g€nire MUs $ d iensoidal body onbining quarra feldsps, proxene &d homblends. FeldJpar loms th€ phenocrysls in a nratrix ofqua.E-feldsptr and mafics. Cey sFnile is a @6e- 10 medium- EBincd rcck with nic.ocline, quartz, or$@lNe, p€rthne, hornblendelndzohite. Light srey stuite is a medium- gained ock consisrine ofmicrccline, odhocls, plagiocLse (aibne b oliselae). epidore, .eenLde. hornblende and rurile. The majorelementchemktr, ofthe ganire do mr show mlch wriaiiotr. The pink g6nne sho*s high conrcdt ofpotash A negalve coneLarion ibr KiO conreDt with rcsper to SiO: i5 very pronounced rbr pink Elanne olins ro iBalkalide.!lua. Bariud dd snontiun show very hish values iorPe6Limala gnnire ( Aiilklmtrera(1991).

The Sholarlr (ll'0415 ;76"4200 ) gdnite. s expoed around Kuniyadikal Md,

( 1 1001 52 :?6042'00") and vachchiparhi (1 1004 15. 1604400 ), tr is a homophanous medium- granred, pin k co loured gBni te, consisting o I qusm, onh oc lase, m icroc line, o liC@le, pe ith iE, aeenine alCite biolite, homblende dd sphehc. l n some places, calciE, ap.tite, sri.ite aE ale obsew.d. The schlie@s nsk the contacl4ne ofrhe Crdiles with rhe hosl !@k. This 8lanite ls emplac€d wnhin the Wynad supFcruslah. SiOl vlries fom 58.76 to 7l%, AbOr 14% to l7v!, NatrO 1.8% to 2.4% md K:O 0.8 to 1.5%. The disribulion ofSiO: is highlynon-lniform wilhin rhe sme rlpe ofgFnire. The pink sBnile ls becoming alkali grdite ar pLaces(Anil

The syenite bodl at Mannapn (10'3000 i76o3200 ) s exFosed s an elongated NW.SE reidinC body covering an area ol8 sq km ii Th.issur Disticr The syenne inrusive, makes shlrpconEcrwith thecharnockire nea.thechario.kire.miCmari€conract. The ock is nedium ro come- grained al ils peripheries and Ends io be coaree-enined rovads the cenre MineRlosicall,, the rock is composed ofalkali feldspar, orrhopyrorene, cliioplroxene and

4mphibole Rith minor mounts of plasioclase, biotite dd opaques. A snall syenire [Aneadimugd syerire) body is located in Krmbala viuage (12']5l5!';76o0700 ) ud about 20 hn easi ofKumbla in KNangod Disrict. The intusive body h6 e €lliptical ourline and coleK an area of5 sq km. The body h intrusive i o rhe Khondalire cmup &d encloes

$rdt{.n3shr.l45 enclaves ot amphiboln in tbe penphe€l pdds. The rcck is meniun io co@ gnin€d. lighr

BGic intusi!6in Kmla. mai.tyrepresenGdbydyke swams jnNNW-SSE to NW-SEirend, cur acrcss all the neL4olphic rocG and rhe ear tjer sfucrural rends. fiet umeborphoed naluE md slralieFphic eiation wirh rhe codnrry focks piompred rhet corelaaon ro the

'lhe b6ic dykes have ben emplaced inro lhe mignatites and chhockite in NNW-SSEtoNw- \E Md r'{E-$Sw d:Fc.ons atong d rmsona ro sra fi!;tu$ respd aty Dohik dykes of Kmla @ oonly quanu tholeiites ftty ctinorhol.iib. The basic dykes of Palhemthitta (91545,,r?604530 ) are senetically unrelated rypes. Th€se dykes have not uidereone dy int mal difieendali@ dujng intrusjon.

The vaiatlon in the chemisrr, of individuai dykes mal, be due io lne cogeneljc differentjal sequence. Doleritedlk€s inrrude de counrry rocks ar an angte sranef rhai 8Oo The dobne 04910":7503400 dykes or Kumpaamba ( ) in Kbnur Disdicr 3hows cross cunins rela onship wirh all de fomations. The b6ic dlkes of Vadanapurm {8o4l O0 :7605400,) at eithe.gabb@icordolernic inmding theBneissic locks. These a.eftndingNNE b SSw aDd NNw to SSEdiMtions md de unmeranorphosed Mine.alogico , alt$esedykes show more or les sme €mposnion except the meralotedres vsiaxon m rhe raceetenents hke Ti.Zrc6beotuiburedro$ediferenriatdesreeofpdriaimehingofrhenandemarefjst.otan

The unmeramorphosed ldoalsye gabbrcic drke wjrh a NNW-SSE ftnd is raced tor oler

30 kn inrhe cenrml pan of KeralE. The rock h nsocdtic. mediufr-grained, porphyritic and r conpls€d ofplagioclse (edesine lo tabodolitt, homblende and opaqu€s. The reponed dgeofT5m.ylorrhelddalayddyke(Sub@aniao,l976)liiksjrintime{etalionsbipwith

The NNW'SSE trending leucogabbrc drkes in cenraL Ke.ala dded bJ, whote rock K,Ar ne$od Save an age of 81 12 m y dtl $e NW-SE rerdin-q doterne dyke 691 I m y. Tne dohnte dykes ae lhoughr 10 hav€ Ep@enled the feeder sy$en for De@ TEp votmic sequences (Radhrlrishno ?/ zl, I 994).

BsicdlkesofPa$anamthitra?r€yi€tdedagesof99N,laro 7MaandrheEaEdyk6which have yielded s86104:! 5 Ma 12?lMadd4?61Md.These wide variations my be due ro a prcfacred history of.dplGmem ed lne effecl of Eocmbriu to pat@2oic tdronorhemal evenB aiIering this rcsion ( Sinha Roy and Ramakrishnan, 1983.)

In Thiruvanmrhapum Dkrricr, AnalDdi &d Nedumainui dolerne dykes @ dared by (-Ar medodandlhewholesckaessare t04i5Maand t2Tr2Marespecrivety(SinhsRorand

Te.ti!ry S€dinerbry rocls

Mio-Pliocene sedinenrary rcckJ ale fairty wid€spead in the surhem costat betr, then remnanrs being noriceable in the entBt and nonhem costat aE4 Thee sedimenrlry mcks consGt ofa *des ofvriegakd cley.and sandstonB wilh tenrtcutar sedsoflignne, known 6 Wml€lli Forndtion. undqlain bj noG compact 6arty studs wirh she| fd€nenls ed thin hoizons of limesbne (Qriton Fomation).

Tre leniar! sdimenE have r gentie dip to*trds wee. The Warkali Fomation exlends in a da@w bel. from Thituvsnanfiapuran (8028'30: 76.5720 ) b Kdamgod (t2.looo,j 7,105900) betw€en coastal rnd fridtand Egjons with intenenjne p.omonroaes of $e crynallire pamvur ocki The Quilon Formarion is mainL, seeD ar {08.4800,,: 76.4000 ) Padappitkam (03'5830 : 76.18'00 ) and some otherploes around Ko am and Atappuzha

Thc Quilon Fomaljon consistiig offossiliferous shelliinesone atrematingwilhlhick bedsof sandy clays &d calcaeous ctays have been reponed ffom padEppakkao (rype iocalit!),Nedumgolm, Edavsi (8"45?0 r76q42'00') and Vskata (8044,00': 7604300,) rnd ChenhrLa(9'qa100:76!20'00)alongrhewestco6rofKemtaTheeuilontime$oneconbins dtrnercus lossih offoraminiaera. comh. chnroids and mottuscs. The Lower Miocene age fof loNer $mtigraphic horizons and the Upps Mioene ase for rhe topmosr beds of rhe euitoi F;!mation indi€te the Iose. !nd upper age tlmirs or rhese ma.ine sedimenh. The

(sr?sbte DistndslNryRepon.Ernakuhm Dinir! I 47 t pre

ihe Wdkalli Fomarion oa Mio-Pliocene age extends all alone the KeGla md.The tTe s€don of ihe warlialli Fomarion described by King (1882) is from the ea cliaaar Varkaia. The expo*d section ar Vdkala cliil is 28-10 m thick consisring ofunconsolidaGd ends oi variegacd clrys. whire pldtic clals, md cdboia€ols sandy clays enclosjne impersislent seams and lenses otlisnile. Thc ctrbona€ous clays and llsnite are oRen inpegnared wnh

Fady thick bols of cebonaceous clays with lignite seams mcuf arcund Naddy!6 kayal, Tamamluld (9008': 76'37), Puliyur (9'1800 : 76'3500'), Palangodi (12'0020: 75'1540),Nil6Mam(12'151)0:75"07'001,Kanhangad(12'i740:75'05'00")ddin$e crill*ctions near Cherula$ur (12'll00"i 75'09'J0 J.The mo$ characrerisric fdure olthe warkalli Fomalion is lhe impersistent natrc of rhe coNtnumr beds, suggesive of shallow

KeraLandehodeofthelaGrneasnwasfistnamedby$eDutchravellef,Buchananl80T

Laterire is widespread in ns disriburion in the midLand regior oi Maiappu6n, Ksnur and

Kassagod districts where ir foms welldeinen mesa. The Archaes cryslalline Ncks and rhe leniary sedifrentary rccks re e{trsively larritised. The lateriE h6 vide d@ldisiribudon in the Sure md o@u6 at alllevels uFo 2000 m, heighlrhouCi mosdy e$ricred to an altitude of50 150 m above MSL. in 1he@6uland fridlmdregion. A fe* bauxnic patches aho oeur wilhin $e laterites. The thickness of laierite cappings vuies 6om e f€w metd to 50 metr€ at places. Ar Chowd (8o2130 i ?7"01'30") in ThiruvDothlpulam Distict dd Charunnur

{8'5010 i 76'4630 ) dd Kundad (8057 00 : 76'4030') in Kollam Dktrict, a zone ofaboul 2_fr thick bauxite h Bognised ar thc coniacr benveei rhe crrnallines Md the ove yrng sedimentafy rocks. The overlying sdinenrary column is aho blankered by laterjleorlaryLne thi.kne$ The bauxile at rhe b6e ol the sedimentlrics iidicacs an eanier pre-WarkallispeLl of laleFlhation. Furiher. th€ trosional featules on rhc top pan of rhe bautite horizon coroboEtesthedtiqunyoftheedlie'spelloflatrithation(MalliksjunaddKapsli,l980) 6en.rally, de lalerib aner $e crlslaltine rocks is mmpact dd rhe lop crue moderarety indumred. The ddk broM crusl p$ses dovnvdd ro pink ond bult cotoued soi taierire. Quanzveins,jointssdirrurcs€n be rl@d lrom rheroptothe bonom olrh€ tatenepofile. pro Th e latcrite fi le over pyroxn e grdu I iles, meL-u hrmalires and sn e isses d€ chamcrerised by relict foli.tion lnlt confoms ro thoseofthe subjaeni Gks which indicare the IAito narure ofthe latcrirc. Poro6 and spongy texturc is disceflribte in taienres, atier mea-uhrmatiies.

Larerite after $e Teniary sedim€ntaries k welt indudled d fte lo! lbf about 2 lo 5 m

Do\nwards, the profile emdes into son larerirervith rcmnants ofgrihtone and culninares imo . zode olvlriegared ciay.

Recent ro sub Recent sedihens ofcoasalsands.sricky black ctaywirh carbonized wood. silry alluvium and lagoonal deposits a.e obseped moslr, ln lhe tow-tying ar6 lrcm Ko an .5130 ltt'2700:1s"403A\ to Pondani and berw€en Kannu. ( :75"2t,as ) and Niles*aBm (12'1s30 :7500316 ). alluvjum is obsesed atone the hajor.ive. valteys. Ar places. along coasal tracrs, rherc'ire Bi*d sandy b*ches composd offine gBiled €ddish smd! Lom kioM 6 \e{i sands.Palaeo beach ridges alremare with maNhy tagoonstcLay in

The sandy stetbes are wid$r belse.n Alappuzna (9oto: 76.20) and Kotuym (g'js:

76qll),upto25 km lnltud f.om theshoreline. fheQualema esoithecoasutprain havebeen dssifiedinro(i)theCuruvaysFomalonreprcsenrinsrheeanie.slGndlinedeposnswnhan elevaron of5-10 mt(il)theViyyam Fomaton ollidatptain depositsi(iii) peri)lr Fornarion berng mainL! offluvial deposih and (iv) rhe K.dappumm Forfrarion representing rhe beach 'deposnr (Krishne Nan, 19391.

A Febble bed is traced ln valapalunam and Taliparaniba. ver banks in Kannurditiicr. tr is !2.1 erPoscd soulh of Valapanan.m (l l'tt l0 . 75 '21 i0 ), Konbit natorh (11.58 :75 ).

Mo@ha (ir '5330 : 75.2030,) dd Ararhiparamba (t2r0600,,r 75.t5.t0,) The size of rhe pebblcs ranges in dimension fiom 45 cn x :] cm to 7 cm x 3 cm wilh occ$jonalcobbtes ol size ll cnr x 12 cm. The b6. of the pebble bed ts generalty 20 b,t() m abore MSL and ar places, $e pebble bed direcd] r€sts over$e bement.ocks. The pebbles ee mosrty otquanz and rdeLy of gmit€ &d [email protected] granulire. Thedhtribuiion ofrhe pebble bed atong$e major nler banks demonsirare itto be ilood pldin deposirs, prcbabtt ofeaftyeuarem4 p*iad Oan c/,/, 1976).ln Malappuram and Kozhikodedisric6, rhepebbte bed k aaced in rhe rive.ine rrru6 a1 Mawr (ll'17.45",75't9()O" ), Cheruvannur (11'128 : 75"4t'ls ) od chelleppaFmbu (l1"1430 :7s'59'l)O') ln Thnulananlhaputr DisLict, $e Quatenarv

(8'1700 : pebble bed occu^ at an elevation of 45 io 50 m above MSL ar Po$enlode Andoorkomm 76'48'56 ),Idaikode (8"40'll :76's049"), Aninsal (8'41'19 :76'4856 ) Md (8"1600 i 76"5230")-

submelled upndr! b dnhs htve been reponed fron a number orpla6 in th€ cotsralaEa oiKonaym and Alappuzha disrricB. indicarins neoiecronic reaclivarion in de se& Carbon

daringorasmple lrom the submerged iorest ar lmvimdgalam indiqE 4 ageoi70i0 t ll0

' ..orrot'o-" i, o) le\N\{ \rf reldrs e rrc'r'a gErnorle\oun neer '.u. rea lonsitudinal Dhwarid irend which had folded allearlier srructures SinceKemlaStare lirllr in rhe wenern linb oflhe frega{tru.1lre alnon all rhe rock distibulioi is dlig!'d in NW-SE dirccion. However, delailed shctural $udies canled our in seleded p'ft of$e (Fi repesnred Ke.ala (Nair md Nair. 2oo I ) had shoM rhEt (a) rhe edliest lolds ) which {e borh on mosscopic sd meg6@pic sqle se lighl appre$ed lolds ofdvmmetncal natue (b) which had eive. rise to uhl plane loliarions wirn chracrerisiic plat] nineFl aliennens th. frfollsonthese folialiorc (poslfolial) are open s)mmekical and have develoPed oainlv onnegdmpics€leandcontolrhedisposilionofthenajorlitholoeies.(c)Subsquenttblds iF, which defom Fr bd Fl axial pLane races are boad folds on nega_sale id€ntiiied \Y{h io r r. longnudinal Dhwdian ftnds sd (d) a brcad sEdre on thse DhNdian rends FNE

i{S\{ is aLso dscipheEble (Fic.2).

Derailed cnallsis ol lhe rcmoie sensing data had relealed rhe presence of a nunber ol signilican!lineme patlemsinWNW ESE.Nw_SE.NrNw SSE.NNE_SSWsdENE-wsw dirccrions (Nan, l99O). Mega snd imemediar. linsoens in WNW_ESE were oriSinallv c.usbl fladurcs and shears which sot sealed or obliGEted bv a number of iSneous grmophtrc The .mplacements ol alkali Sranite, stcnne, gabbrc, anonhosne, elc afrplac.menh alons the Bavali lin€amentdd those along the Ach€nkovillineahetu borh or which tending in Ihis diMlion had gilen ages dging i.om 500 678 Ma Hence lhev aF

iden tified iobeihe olde$ iineanent The Bavali lirdenl foms $e Neslen lcrminaion of coincide rhe Mor& shee. The NW-SE lrending lin@ents mnnnuie mega linesenb ed dlkes hale snh the baic dykes scudng rhmushout lhe leng$ and bread$ aflhe slare Ttese

I ases sive. mging ftom 6l to 144 Ma. The NNr1'-SSE r€ndins linedents are eeneElly intemediare lin@e,rs end se amibuled ro fradures, fautb dd mejorjoid pmems in lhe a@. Il is to@gnircd that the NNW,SSE rending tin@en6 d€fine a weok zne atong which rhe wes cosr evolved by faulting. The s$en limir ol6e Tenjary bdin is found Esriccd alougthis lineamenr diection. These in@ments oeuftins atong lhe west co6r mbeadire as sugScsred by tlte p.ogradarion of the oa$ we$ of r,Lrese tin@en6 {Nair, 1937). The rrneanenh inNNE-SSW arcFominenrand areideirified wirhmajorfrrcturesand rhh roeerher vith rhose in NNw-ssE are raken to consritute a conjusale sysrem of faulrs in a N-s cohpre$ive regime due ro E co ision of the rndixn ptate The ENE-wSw rending lifcafrenB are inrmeniaie tinem€ns aid ae se - devetoped ii rhe nonhem pans ollhe KeraLa Sincethese linemenrs rruncate orher tineamenbaseljdenced especia y jn rhe c6hl ererches rt is considered rhe youngesr Many a recom rremors reponed are atigned ii lhjs dimcrion $d h€nce @nsidqed neorectonicalty acrive.

The Precambrian cryshlline rocks of Keula se chiefly frehpelites, chdockites wilh asociated gneisses md Crdulires, schistose mcks wirn disiii.t metapetiric and meFmanc / u tmmatic afiniry and e@itc derivdjves whch include $e peninsular gnekses and Diigmatnes. Excepl$e Wynad schis$andrhe Venead group, $e butkofrherysra iic focks s[owgdnulrret upperamphibotiretaciesofmeradorph]sm Wynadschi$disptaysaprograde rmphiboliE facies mebmorphisn and the rerogre$ion of rhose ocks teads ro toser amphibolite facies metmorrhhm. Th. vsr chernockite betr occuriig on eirher side oflhe

$!nad schistbelt, in norih Keot4 shows p.trognph ic evidences ot prcg.ade and refioerade readLotr (Nafrbiar, 1996) The ocks ofthe veigad Croup sho{ greenschi$ to tower amphibolire ircies of progdde meborphjsm. The otder inirusile bodies show €ffecls of ,ncrprenrmetsmolphBm,ntrkedbycLoudineoffetdsparandbendinsofNintame ae.

Recent investigarions on lie pressur€ - Gnpe€ruE rsnge fo. rhe formation oicharade.isrtc mlne.al sui6 within the ner3norphic rccks provideafair idea on rhepoly-neteoDhic hisro.r ollheock$ns.RocksofrheKhondatilebehofsourhKemiaindicarealempeEtureraigeof

650to850'CandpressuEs5lo6kb(Srikdkppasrdt t98j) tnlheThnuvanarhapuramarea, ihe rempedture at the peak of mebmorphism indicared bl rhe mineEl $sembtaees of fi e catc, jili.ate rocks ls abour 8l0t at 5 K barconsidfting tbc vapoufabsenr earner lordjng equitibr a (Satnh Kmar and Saibsh, 1996). The scapolite equjtjb.ia indiclres a p$r nehno$hn- remperatule ofabove 80afc. srabte horopes in re marde bands suegesr $al thee sas no

{nci Ksrasbr :91 pc as v. otihrarionof€xtemrlflLids. LocalinfiLtntlon ofexternal carbonic fluid rook Plac. durins d..otr,t)osirioD Synthcsn olsuch data lrcm dilftcnr lineamenrsh.ar boufd scgm.i6 n K..rh i',dicare vrryine meramorphic cond:lioRs and uplili lriioO lr is cko strfrne rd rbr rhcr L\ a ptugrersive decl ne i| the uplih .f dlitlrenr seldrens tron nonh ro sodl {@ B$llJf fi Efi i G':',',''ALS ilffiEdAsE W H ffi g