PR01_copertina_R_OK C August 20-28,2004 Florence -Italy

Field Trip Guide Book - PR01 Prestige FieldTrip M. Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Leaders: PAKISTAN TO THEEASTHINDUKUSH, FROM THEINDIANPLATE A GEOLOGICALTRANSECT 32 Volume n°1-fromPR01toB15 GEOLOGICAL CONGRESS nd INTERNATIONAL PR01 28-05-2004, 18:45:41 The scientific content of this guide is under the total responsibility of the Authors

Published by: APAT – Italian Agency for the Environmental Protection and Technical Services - Via Vitaliano Brancati, 48 - 00144 Roma - Italy

Series Editors: Luca Guerrieri, Irene Rischia and Leonello Serva (APAT, Roma)

English Desk-copy Editors: Paul Mazza (Università di Firenze), Jessica Ann Thonn (Università di Firenze), Nathalie Marléne Adams (Università di Firenze), Miriam Friedman (Università di Firenze), Kate Eadie (Freelance indipendent professional)

Field Trip Committee: Leonello Serva (APAT, Roma), Alessandro Michetti (Università dell’Insubria, Como), Giulio Pavia (Università di Torino), Raffaele Pignone (Servizio Geologico Regione Emilia-Romagna, Bologna) and Riccardo Polino (CNR, Torino)

Acknowledgments: The 32nd IGC Organizing Committee is grateful to Roberto Pompili and Elisa Brustia (APAT, Roma) for their collaboration in editing.

Graphic project: Full snc - Firenze

Layout and press: Lito Terrazzi srl - Firenze

PR01_copertina_R_OK D 24-05-2004, 15:46:48 Volume n° 1 - from PR01 to B15

32nd INTERNATIONAL GEOLOGICAL CONGRESS

A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN

AUTHORS: M. Gaetani1, J.P. Burg 2, A. Zanchi3, Q.M. Jan4

1 Dipartimento di Scienze della Terra “A. Desio”, Università di Milano - Italy 2 Geologisches Institut, ETH Zürich - Switzerland 3 Dipartimento di Scienze dell’Ambiente e del Territorio, Università di Milano-Bicocca - Italy 4 Centre of Excellence in Geology, University of Peshawar - Pakistan

Florence - Italy August 20-28, 2004

Prestige Field Trip PR01

PR01_R_OK A 24-05-2004, 15:50:31 Front Cover: Panoramic view of the Chateboy Glacier and Koyo Zom (6871) from the Vidiakot area (Baroghil, upper Yarkhun Valley, Pakistan)

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Leaders: M. Gaetani, J.P. Burg, A. Zanchi, Q.M. Jan

Introduction Maps. Topographic maps: Pakistan 1: 500,000, Sheets The fi eldtrip provides a geological cross-section in Gilgit, Hunza, Tirich Mir, Peshawar. Northern Pakistan from the margin of the Indian Plate Geological maps. to the E Hindu Kush terrane, through the Kohistan Khan, K.S.A., Latif, M., Fayaz, A., Khan, N.A. and Island Arc and the Karakoram Range (Figs. 1 and 2). Khan, M.S.Z. (2000). Geological Road log along the The meeting of participants is scheduled for the Karakoram Highway: Islamabad to Khunjerab Pass.

Figure 1 - Tectonic sketch map of Northern Pakistan and surrounding regions. Modifi ed from Zanchi et al., 2000 and Boulin, 1988. MFT: Main Frontal Thrust, MBT: Main Boundary Thrust, MMT: Main Mantle Thrust; SS: Shyok Suture; TMF: Tirich Mir Fault Zone, EHK East Hindu Kush, ACM Alitchur mountains, RPZ: Rushan-Pshart Zone; WAS: Wanch-Akbaital Suture, N-P: North Pamir, C-P: Central Pamir, SE-P: SE Pamir, SW-P: SW Pamir, WAZ: Waziristan, K: Kabul. 1: Quaternary, 2: Tertiary foredeeps, 3: Paleozoic belts, 4: Terranes of Gondwanan affi nity, 5: Kabul Block, 6: Wasser-Panjao Suture, 7: Waziristan ophiolitic complex, 8: Kohistan-Ladakh arc terranes, 9: Himalayas. Heavy lines represent main sutures.

afternoon of 22 June in Rawalpindi-Islamabad. The Highways geological Map Series, Map N°1. itinerary will follow the Indus Valley up to near Gilgit Searle M.P. & Khan Asif M. (1996) – Geological Map (Northern Area), then it continues along the Gilgit of North Pakistan, 1: 650,000. River, crossing the Shandur Pass and entering the Le Fort P. & Gaetani M. (1998) – Introduction to North West Frontier Province (NWFT) at Mastuj. the Geological Map of Western Central Karakorum, Along the Yarkhun Valley up to the Baroghil Pass and North Pakistan Hindu Raj, Ghamubar, and Darkot PRO1 to B15 n° 1 - from Volume back to the town of Chitral (see back cover). Most Areas 1: 250,000 scale. Geologica, 1-68. of the travel is done by minibus and jeep, lodging in Le Fort, P. and Pêcher, A. (2002). An introduction to hotels. Five days however, along the upper Yarkhun the geological map of the area between Hunza and Valley are on foot, with overnight in tents. Arrival in Baltistan, Karakorum-Kohistan-Ladakh-Himalaya Rawalpindi-Islamabad scheduled for the evening of 7 region, Northern Pakistan (scale 1:150.000). July, to allow participants to fl y home the 8th of July. Geologica, 6/1, 1-199.

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Volume n° 1 - from PRO1 to B15 PR01 - PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan continental blocks. time, whichisdocumentedonallGondwana-derived 2001), recordthewidespreadmagmaticevent ofthat et al.,1980, Anczkiewicz 1998,DiPietro &Isachsen which have beendeformed into orthogneiss(LeFort remobilised gneisses. Around 500Maoldgranitoids, epicontinental marinetransgressionon1.5-2.2Gaold Cambrian stromatoliticdolomitesrecordthe gneisses andsediments. represented bymid-ProterozoicandPaleozoic originally depositedontheIndiancontinentalcrust thick, imbricatethrustpileofMesozoicsequences Altogether, itisalow-grade assemblageofa20km Lesser-) HimalayaofPakistan (Chaudhryetal.1997). sedimentary beltconstitutetheso-calledLower- (or metamorphic unitsandasouthern,fold-and-thrust south, andtheIndusSuturetoNorth.Northern out betweentheMainBoundary Thrust (MBT),tothe The northernmostpartsoftheIndiancontinentcrop The IndianPlatemargin Regional geologicsetting provided totheparticipants. Hindu Kush, 1:100,000scale. A pre-printcopy willbe – GeologicalMapoftheNWKarakoram andE Zanchi A., GaetaniM., Angiolini L.,(inpress) Figure 2-Satelliteoverview ofthearea crossedbythefi magmatic agesofmetabasalticdikes starting intheMiddle-Paleozoic. Early-Permian sandstones andlimestones)isofGondwana type, Much ofthePhanerozoicshelfsequence(shales, 1998, DiPietro&Isachsen2001) of pervasive magmatism duringrifting(Anczkiewicz gneiss intrusive intoolderIndiangneissareevidence with thebreak-upofGondwana Ma mostoftheLower Himalayarocks werelocated Thermochronologic studiessuggestthatbefore13 et al.1993,O’Brien2001,Kaneko etal.2003). likely derived frombasalticPermiandykes (Tonarini in theKaghan Valley, ofcoesite-bearingeclogites kbars atca.50Maisindicatedfromtheoccurrence, of theIndiancratontodepthsequivalent to27-32 Chamberlain etal.1991).Subductionofatleastparts between 75and40Ma(Treloar etal.1989, All theserocksweredeformedandmetamorphosed side ofNeo-Tethys. subsidence ofacontinentalmargin, onthesouthern is thatofcarbonatesdepositedduringthermal history sedimentary Late Triassic.Mesozoic The Marine shelfsedimentationwas re-establishedinthe Carboniferous (Pogueetal.1992,Pogue1999). that theonsetofextension tectonicsisEarly (Kazmi &Jan1997).Sedimentaryrecordsindicate suite ofalkalineintrusions,includingcarbonatites eld trip. . , which isassociated Rifting produceda

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either beneath a paleo-foreland basin or beneath Main graywackes and volcanoclastic rocks form a probable Central Thrust (MCT)-related nappes. back-arc basin of Cretaceous age. They grade Molasse conglomerates siltstones and shales (termed upward into fi ne grained shales and tuffs and contain Siwalik or Sub-Himalaya sediments) lap onto the limestones with an Albian-Aptian fauna (Pudsey et Indian Shield. In detail the discontinuous series al. 1985). comprises most of the Cenozoic but there was a Volcanites (Chalt Volcanites) are calc-alkaline general lack of sedimentation during the Late Eocene andesites to rhyolites succeeding to andesitic lavas, and almost the entire Oligocene. This unconformity tuffs and agglomerates of Early Cretaceous age. of 15-20 Myr may refl ect an important change in Exceptionally well-preserved pillow lavas are orogenic processes. One interpretation involves the primitive island-arc-type, tholeiitic lavas that possibly passage of a fl exural forebulge migrating southward represent part of an ophiolite assemblage obducted through India. Late Oligocene to Early Miocene during the Kohistan-Asian collision. The size of this fl uvial formations record the emergence of the oceanic back arc basin (with respect to the Kohistan) Himalaya Mountains. is conjectural. - To the Southwest and within the Kohistan Complex, The Kohistan Island Arc Complex: metasedimentary sequence of deep marine origin Outline (Dir, Utror and Kalam Groups) yielded Eocene fossils The Kohistan terrane in NE Pakistan (Fig. 3) is in upper-level limestones. Depositional models regarded as a fossil island arc obducted between the point to rapid subsidence in Paleocene times in an collided Indian and Asian plates (Bard et al. 1980, extensional, restricted basin. Associated volcanic Tahirkheli et al., 1979). Owing to the admirable and volcanoclastic series are calc-alkaline basalts, quality of exposures, the Kohistan offers an unrivalled basaltic andesites and andesites, emphasising an arc opportunity to investigate the structure of an island environment (Sullivan et al. 1993). arc and related subduction processes (Bard 1983, Searle et al., 1999, Treloar et al., 1996). In particular, PLUTONIC CRUST numerous time markers in the form of intrusive bodies Kohistan batholith: is a name that gathers intrusive make the Kohistan an exceptional place to study the calc-alkaline granitoids. The fi rst plutonic stage is signifi cance of magmatic structures in the deep crust dated at ca 105 Ma. Stages 2 and 3 are dated between of an arc system.(Fig.3) 85 and 26 Ma. Stage 1 and early stage 2 plutons have isotopic signatures characteristic of a mantle The Kohistan sequence displays a structurally coherent derivation. The isotopic signatures of younger plutons section of an island arc terrane, comprised of a 30 to show evidence of an increasing crust to mantle ratio, 40 km thick section of metamorphosed, plutonic, with the latest magmas being entirely crustally volcanic and sedimentary rocks. This succession is derived. This evolution is interpreted as the result interpreted as plutons intrusive into an oceanic crust of arc thickening and lower arc melting following and overlain by the calc-alkaline lavas and associated suturing to Asia (Petterson & Windley 1985, 1991). sediments. Accordingly, the interpretation is an intra- oceanic arc that developed during the Cretaceous Gabbronorites: a massive body of locally layered through a north-dipping subduction in the equatorial gabbronorites marks the axis of the arc. It is the more area of the Tethys Ocean (Yoshida et al. 1996). than 8 km thick and 300 km long Chilas complex Six main rock assemblages from north to south, i.e. thought to be a layered magma chamber intruded into downward sequence, are present. the arc in Cretaceous times. In detail, it is a stratiform complex of norites, noritic gabbros and a string of UPPER CRUST lenses of diverse ultramafi c-mafi c-anorthosite (UMA)

Upper crustal sequences pertain to two geographically association. The UMA represent apices of intra-arc PRO1 to B15 n° 1 - from Volume distinct domains. mantle diapirs that served as porous fl ow conduits - Just south of the Northern Suture, they consist of to feed the gabbro-norite. The gabbro-norite cooled interlayered volcanoclastic sediments, volcanites and and equilibrated at 600-800°C and 6-8 kbar. A Sm-Nd rather immature turbidites deposited in a deep-water internal isochron yields an age of c. 70 Ma, consistent environment. with the conventional zircon U-Pb age of 84 Ma Sediments (so-called Yasin Group) are shales, (Schaltegger et al. 2002).

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Volume n° 1 - from PRO1 to B15 PR01 - PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 3-Structuralsketch mapoftheKohistan Island Arc Complex. 24-05-2004, 15:53:26 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Meta- gabbros to tonalites: (so-called Kamila sub-arc magma chamber (Bard et al., 1980). Later amphibolites) form a thick pile of imbricated calc- geochemical analyses suggested that it was generated alkaline laccoliths variably sheared in amphibolite by intra-arc rifting and subsequent mantle diapirism facies conditions. Small inliers of metasediments (Khan et al., 1993). The latter interpretation is and metavolcanic rocks screen these laccoliths and consistent with the gabbro-norites having intruded rare granites belong to the plutonic association. Few volcanic and sedimentary components of the arc. intrusion ages are available. They span from 99 to 82 Petro-structural observation supportively suggests Ma, giving evidence for a succession of short-lived that the ultramafi c-mafi c-anorthosite associations plutonic events; 82 Ma-old rocks are kyanite-bearing occurring as a string of lenses over the >300km length pegmatites produced by partial remelting of deeper of the gabbro-norite represent apices of intra-arc lithologies in the arc (Schaltegger et al., 2002). Ar- mantle diapirs that served as porous fl ow conduits to Ar cooling ages on hornblendes cluster around 80 feed the gabbro-norite (Burg et al., 1998). According Ma, hence providing evidence that this part of the to the zircon U/Pb age of gabbronorites, rifting is Kohistan island arc complex was cooled below c. about 85 Ma old (Schaltegger et al., 2002). 500°C in the Late Cretaceous (Treloar et al., 1989). The Chilas suite of mantle diapirs points to splitting of Shear strain localisation took place continuously from the Kohistan arc, with initial rifting taking place at the magmatic emplacement to solid state deformation island arc as documented in modern island systems during cooling of the gabbroic and dioritic plutons, (e.g. Rocas Verdes). The UMA outcrops point to between 100 and 83 Ma (Arbaret et al., 2000). The mantle diapirism as a key mechanism in opening related shear strain probably represents arc-related back-arc basins between a volcanic and a remnant deformation during subduction of the Tethys oceanic arc, the latter perhaps now seen as rocks screening the lithosphere below the Kohistan Arc Complex. Kohistan Batholith.

MANTLE Obduction - metamorphic record The so-called Jijal-Patan Complex, is composed The Kohistan Arc and India were assembled during of more than 3 km thick ultramafi c rocks overlain closure of Tethys, which produced thrusting along by garnet-plagioclase granulites. Garnet- and the Indus Suture. Within the Suture, a discontinuous plagioclase-free peridotites and a few pyroxenites but up to 20 km wide zone of imbricated ophiolites, dominate the lowest section. The Jijal peridotites greenschists and blueschists is locally referred represent the sub-arc mantle (Burg et al., 1998). to as “mélange unit”. It is a dominantly fore-arc The sharp contact between the ultramafi c rocks related assemblage obducted onto the Indian and the overlying granulites, with well-preserved plate (Anczkiewicz et al. 1998). In the footwall, igneous structures, is the intrusive contact of lower the geology of the northern margin of the Indian crustal, calc-alkaline garnet-gabbros (the granulites) plate is remarkably uniform. However, two high- within mantle rocks (Burg et al., 1998). The contact pressure metamorphic events have accompanied is also the lower boundary of the arc crust, i.e. the the India-Kohistan convergence: blueschist facies arc-Moho. In the granulitic gabbro, metamorphic metamorphism at ca. 80 Ma is linked to oceanic overprint essentially marks isobaric cooling within subduction, eclogite facies metamorphism at ca. 50 granulite facies conditions (starting T > 1150°C at Ma is linked to continental subduction. depth > 50 km although early metamorphic pressures may have increased. The granulitic gabbros have later PRE-COLLISION EVENTS re-equilibrated at >700°C and 15 + 4 kbar, which are Blueschists imbricated within the suture between pressure conditions similar to those calculated from India and the Kohistan Arc yielded 40Ar-39Ar and the underlying ultramafi c rocks (Ringuette et al., Rb-Sr, phengite and Na-amphibole ages at ca. 80

1998). Sm-Nd isochrons at c. 95 Ma date cooling Ma and thus record a pre-collisional, Early/Late PRO1 to B15 n° 1 - from Volume and provide the minimum age of the Jijal ultramafi c Cretaceous metamorphism during subduction of sequence (Anczkiewicz & Vance 2000, Yamamoto & the Tethys oceanic lithosphere (Anczkiewicz et al. Nakamura 2000). 2000). Rapid exhumation and cooling of these high- pressure metamorphic rocks probably took place in an Arc splitting accretionary prism system dominated by corner fl ow The calc-alkaline Chilas norites and noritic gabbros processes. were fi rst interpreted as having crystallised in the

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Volume n° 1 - from PRO1 to B15 PR01 - PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan (Zeitler 1985). similar fi along theIndusSuturesince20Ma,asindicatedby activity. Nosignifi uplift withassociatedbrittlefaulting andseismic refolded thrustpatterns,large slabfoldingandrapid The post-Eocenethrustdirectionsgeneratedcomplex, Kohistan Arc againstthissegment oftheIndianplate. part ofthecollisionsandfi fabrics intheserocks,therefore,recordanimportant et al.1989). The metamorphicandrelatedstructural 38 Maandmuscovite coolingagesof30Ma(Treloar on theIndianplategive coolingagesofhornblendeat Ar/Ar mineralagesofthemetamorphosedsequences et al.1995). metamorphosed inhigh-pressureconditions(Spencer northern margin ofIndiawas deeplyburied andbeing ages ofeclogitesindicatethatatabout50Mathe U-Pb agesofsyn-metamorphicgranitesandNd-Sm metamorphism intheIndiansequences. Collision withIndiadeveloped Barrovian C in (Treloar etal.,1989).However, asignifi Windley 1985)andmeanagedespiteexcess Argon Ar-Ar ageonhornblendebyD.Rex, in(Petterson& intrusion ofa75Maold,mafi pillow lavas next tothesuturewere deformedbefore (Debon etal.,1987,Coward etal.,1987)and2) Eocene agearefoundonbothsidesoftheSuture arguments. 1) Undeformed subalkalineplutonsof closed intheLate-Cretaceousonbasisoftwo It hasbeeninferredthattheNorth-Kohistan Suture which separatestheLadakh Arc fromtheKarakoram. Suture Zoneeastward becomestheShyokSuture, Suture, insouthern Tibet. As suchtheNorth-Kohistan and, assuch,arewesterncontinuationsofthe Tsangpo Sutures weretwo branchesoftheNeotethysOcean Complex, totheSouth. The North-Kohistan andIndus to theNorth,andKohistan Paleo-Island Arc between theKarakoram margin oftheEurasianPlate, The North-Kohistan Suturemarksthefault contact The North-Kohistan Suture Zone involved multipleevents. closure remainsunsettled,probablybecausesuturing did notclosebeforetheMiocene. The ageofthis North-Kohistan Suture,theShyokSuture inIndia, 1983) suggestedthattheeasterncontinuationof (Brookfi younger (Debonetal.,1986,Parrish & Tirrul 1989). amount oftheKarakoram granitoidsis25Maold,or OLLISION eld &Reynolds 1981)and(Reynolds etal., ssion trackagesonbothsidesoftheSuture - RELATED cant movement hastaken place

EVENTS nal emplacementofthe c dyke, (unpublished cant classifi according totheirpresumedtectonicorigin. This prism, leadstoredefi slices, whichmayrepresentareactivated accretionary basin?). The systematicorganisation ofthelithologic the Neotethysoceaniclithosphere(oceanicback-arc therefore theserpentinitesconsideredtoderive from the North-Kohistan suturewhoserealmarkers are No high-pressurerockshave beenfoundalong the lateMiocene. movement hastaken placealongthisfault zonesince 13Ma; accordingly, noorlittle vertical differential apatite partialannealingzonetogether, around11- suture show thattherocksoneithersidepassed the suture.Similarapatiteagesonbothsidesof They are13Ma(apatite)and20Ma(zircon)southof of thesuture,are11Maand20Ma,respectively. fi component. IntheDrosharea,towestyoungest recent sinistralstrike-slip faulting withthereverse Brittle deformationisprincipallyrepresentedby (3) crenulationlineationsinblackschistsandslates. marbles, (2)curved foldaxes ingreen schistsand the stretchinglineationsinconglomeratesand events have beenrecognised,representedby(1) deformation. At leastthreeductiledeformation The North-Kohistan SutureZonedisplayspolyphase on bothsidesandwithinthesuture. segment. Northandsouthvergent structuresarefound reverse componentismoreimportantalongtheE-W component dominatethewesternsegment. The al., 1989).Sinistralfaults withaminorreverse the originalsuture(Coward etal.1986,Searle anastomosing, brittlefaults thathave faulted away well-defi a 1-7kmwideimbricatezoneinwhichsliceswith Karakoram tothenorth. The so-calledmélangeis Complex, tothesouth,fromshelfsedimentsof volcanic andsedimentary rocksoftheKohistan Arc al. 1985a,Pudsey 1986). The “mélange”separates in aturbiditic,slate-dominatedmatrix(Pudsey et limestones, redshales,conglomeratesandquartzites sedimentary formationsandsedimentsthatinclude greenstones derived frombothvolcanic andvolcano- of serpentinitederived mostlyfromharzburgites, Suture isdescribedasamélangecontainingblocks the northernboundary(Fig.3). The North-Kohistan western Kohistan boundarytonearlyE-Walong suture zoneturnsfromitsSW-NE trend,alongthe to (Desio1964,Desio&Martina1972). The In Pakistan, earlygeologicalinformationisdue ssion trackagesonapatiteandzirconfromthenorth cation istentative andthusmustbeconsidered ned lithologiesareboundedbyaseriesof ne themainlithologicalunits 24-05-2004, 15:53:30 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Figure 4 - Simplifi ed structural map of North-West Pakistan. (Modifi ed from Gaetani 1997) with caution or even suspicion, in particular because and the calc-alkaline mylonitic gabbros and of the lack of ages. amphibolitic metavolcanodetritics of the Kohistan Batholith. Pebbles in low-grade red conglomerates Neotethys rocks are elongated, hence defi ning a stretching lineation The North-Neotethys Ocean lithologies are composed with variable directions. of low-grade pelagic to hemipelagic sediments, Fossiliferous (rudists, orbitolinoids) reef-limestone banded cherts, pillow lavas, calcschists, black sequences occur within green basaltic to andesitic shales, serpentinites and talc-magnesite schists volcanites (Pudsey et al., 1985b). It is not clear yet, derived mostly from harzburgites. However, no whether this unit, squeezed within the suture zone, typical ophiolitic sequence has been recognised. derived from the Karakoram or Kohistan terrane, or Serpentinites occur either as massive lenticular and both. fault-bounded blocks or (mainly) as thin schistose shreds along major faults. Gabbros have locally Karakoram intruded serpentinites. The meta-ultramafi c rocks The defi nition of Karakoram in a geographic sense locally occur as talc-magnesite felsen and schists, (Mason 1938) hardly coincides with the boundaries

indicating circulation of CO2 fl uids within the suture of the “geological” Karakoram (Fig. 4). fault system. The mineral parageneses indicate greenschist facies metamorphism. The southern geological boundary coincides to the PRO1 to B15 n° 1 - from Volume east with the Shyok Suture zone, reactivated along North Kohistan rocks the Main Karakoram Thrust, called also Northern The northern margin of the Kohistan Arc comprises Suture (Tahirkheli et al., 1979; Hanson 1989; Searle greenschist-facies basaltic and andesitic volcanites, 1991) and here defi ned as North Kohistan Suture volcanodetritic and shelf-type sediments that overlie Zone. To the west, the geological boundary should turbiditic red shales, sandstones and conglomerates, extend beyond the geographical one, drawn at the

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Little Pamir. Kush liesnorthoftheKarakoram andmerges intothe Zanchi etal.,2000).Inthisinterpretation,theEHindu the Tirich MirFault (Buchroithner&Gamerith1986; (Kafarskyi & Abdullah 1976)andprobablylinked to This lineament,canbetracedthroughthe Wakhan sediments ofNorthernKarakoram (Zanchi1993). Misgar Slatesarethrustover thePermo-Cretaceous the KilikFault inChapursan(Fig.4),wherethe Pamir) ispresentlyhampered. A soundlimitisalong is poorlydefi 2000). To thenorth,boundarywithLittlePamir Boundary Zone(Gaetanietal.,1996;Zanchi of the“geological”Karakoram issetat Tirich Mir Yarkhun Valley andbeyond. The westernboundary units continue,fairly homogeneously, through tothe included becausebothmagmaticandsedimentary Karambar Valley. The HinduRajRangeshouldbe I The Karakoram Range to beddingandSEverging thrusts. parallel andsteeplyNWdippingfoliationsubparallel amphibolite facies metapelitesdisplayamain,suture- Locally, wedgesofmylonitic gabbrosanddiorites are alsoattributed totheKarakoram active margin. conglomerates interlayeredwithgreenishvolcanites Baltistan andLadakh). Volcano-lithic sandstonesand (the so-called“SouthernMetamorphicBelt”inHunza, the easterncontinuationofsouthernKarakoram metamorphic gradeisheresignifi to Neogeneagefarther northofthesuture. The undeformed calc-alkalineplutonsofCretaceous limestones andwhitemarblesintrudedbynearly greenschist facies, shelftypesedimentslike micritic generally representedbybrown andblackshalesin In thesouthernmostKarakoram, lithologiesare Karakoram marginrocks in composition,andintrudingintoalarge northern plutonic rocksalsovarying from dioritetogranite 2) theGhamubarcrystallinemassiscomposedof and Baltorotransects. increase ofthemetamorphicgradealongHunza which itishardlydistinguishablebecauseofthe To theEast,thisunitmerges withthebelt3),from Cretaceous detriticandpartlyvolcanic formations. brachiopod-bearing limestone,isoverlain byLower with intercalationofconglomerate,andbryozoan- sedimentary unit,composedofslatesandarenites 1) To thesouthandonlyinwest,ameta- respectively: T

consists offi ned, but accesstothe Wakhan (Afghan ve belts,fromsouthtonorth, cantly lower thanin

granitoids. DatingofthisbimodalplutonismbyK-Ar biotite andamphibole,two-mica peraluminous plutons: Mg-Kmetaluminousgranitoidswith sedimentary beltandintheMisgar Slatesarebimodal Northwards, intrudedintheNorthernKarakorum from 63.4±2Mato42.85.6(Debon1995). body isalsofound.Rb/Srisochronsgive ages quartz monzonites(Debon1995). A smallgabbroic adamellites, andalsowithquartzmonzodiorites metaluminous orslighltyperaluminousgranitesand of ittheBaturaPlutonicComplex outcropswith al., 1983;Crawford andSearle1992). To thenorth reliably datedat95±5Ma(U-Pb,zircon)(LeFort et Hunza PlutonicComplex, basicallyagranodiorite, The Hunzatransect,fromsouthtonorth,crossesthe emplacement age. plutons withdifferent compositionanddifferent Different transectsthroughtherangecrossdifferent Karakoram Range. These plutonicintrusionsformtheback-boneof tectonometamorphic history(Debonetal.,1987a). in age,chemical-mineralogicalcomposition,and of large plutonicunits displayingmajordifferences It isacompositebodymadeupbythejuxtaposition Karakoram Batholith Karakoram. rocks oftheKarakoram BatholithandoftheNorthern During thefi the Tirich MirBoundaryZone(TMBZ). The boundaryagainsttheEHinduKush ismadeof unknown ageandbylow gradephyllites. the NWbyabeltofvolcanic basaltsanddolostonesof sedimentary successionupto4-5kmthick,bound basement covered byanOrdovician toCretaceous the NorthernKarakoram. Itconsistsofacrystalline 5) thenorthern,mostlysedimentarybelt,forming inclusions; formations maybeincludedassqueezedstripsor south bythemafi granite beinginthecentre,fl varying fromdioritetograniteincomposition,the Batholith (KB)ismainlymadeupofplutonicrocks 4) thenortherncrystallinemass,Karakorum and Mesozoicbivalves (LeFort &Gaetani1998); have beenfound(Hayden,1915;Ivanac etal.,1956) in whichUpperPaleozoic bryozoansandbrachiopods formations, includingarenites,slates,andlimestones unit, iscomposedoflow-grade meta-sedimentary 3) theintermediatesedimentaryunit,Darkot moving totheeastinHunza Valley, strip ofgneissesandmigmatites. This unitdisappears eldtrip wewillobserve withsomedetails c plutonicrocks.Meta-sedimentary anked tothenorthand 24-05-2004, 15:53:39 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

amphibole and biotite ages, suggests primary cooling adamellite, alumino-cafemic with a calc-alkaline ages around 110/105 Ma (Debon et al., 1996). affi nity (Le Fort et al. 1994). For geochemistry refer The Karambar transect to the west of Hunza also to Le Fort in Le Fort & Gaetani (1998). shows a large development of the non-alkaline Hunza Plutonic Complex in the southern and central part, The Northern Karakoram followed to the north by a subalkaline porphyritic sedimentary succession (Fig. 5) granite (Warghut granite) and then by a composite It is arranged in several stacked thrust sheets with group of fi ne grained granitoids with mafi c enclaves. internal stratigraphy partially different. Peculiar to this transect is the Koz-Sar alkaline Transgression onto the crystalline basement occurred complex that from monzonite and quartz monzonites under frank marine conditions and a muddy shelf gave a Rb/Sr isochron of 88± 4 Ma. (Debon and Khan environment extended through the whole Ordovician 1996). and Silurian (Le Fort et al., 1994). Arkosic sands The Yarkhun gorge transect will be visited during the were deposited as coastal bars. Sedimentation rate fi eld trip and also displays three plutonic bodies. was low, usually not exceeding 10 m/Ma. Carbonate Of them, the Darkot Pass porphyritic granite gave a sedimentation was episodic, because of terrigenous Rb/Sr isochron of 111±6 (Debon et al. 1987; Le Fort pollution, the fairly southern paleoposition of the and Gaetani 1998). Northern Karakoram in the southern hemisphere, and This complex of intrusive bodies spans in age from because of cold marine currents originating from the mid-Cretaceous to Eocene and refl ects the northward polar regions (Tongiorgi et al., 1994). subduction of the Neotethys oceanic crust below the The Paleozoic sedimentary successions grow in Asian margin and the following collision related thickness and are most complete when moving from phenomena. south to north in present coordinates. In the Axial Zone the Permian arenites of the Gircha lie directly Northern Karakoram above the slates of the Lower Paleozoic Baroghil The Northern Karakoram includes a metamorphic Group (Gaetani et al., 1996). In the Chillinji Zone, crystalline basement (Le Fort et al., 1994) and a dolostones, hybrid arenites and coral baffl estones sedimentary cover spanning from the Ordovician to (Chilmarabad and Shogram Formations – Devonian) the Cretaceous (Gaetani 1997). are interposed between the slates of the Baroghil The Crystalline basement of Karakoram consists of Group and the Carboniferous-Permian terrigenous low-grade quartzites and migmatites, which are in succession (Fig. 6). turn intruded by a granodiorite. In the Baroghil-Lashkargaz thrust sheets the Devonian The quartzites (Chikar quartzites) consist of dark- succession is represented by the two members of grey siltstones and quartzites, largely derived from the Chilmarabad Fm. and only the lowermost part greenschist-facies metamorphism of poorly sorted of the Carboniferous succession is preserved. It is subarkoses. This metaterrigenous unit forms km- unconformably overlain by the Gircha Formation. wide open folds, and is transformed into hard spotted In the Karambar thrust sheet the succession reaches schists and massive hornfels-like rocks close to the its maximum thickness with the Lower Devonian contact with the granodiorite. Granitic dikes intrude Vandanil Fm. interposed between the Baroghil group the metasediments. and Chilmarabad Fm. The Devonian-Carboniferous The migmatites occur to the SE of Chikar, and up sections exceed 2000 m in thickness and also contain the right bank of the Darkot Pass glacier, where the Upper Carboniferous rocks. metasediments become increasingly intruded by We interpret this Paleozoic transect as a part of the granitic dikes. In a few km, the injected metasediments continental margin of the Karakoram Terrane, facing seem to gradually give way to migmatites, and a deeper basin mostly fi lled by the Wakhan/Misgar

into anatectic granite engulfi ng masses of nebulitic Slates. PRO1 to B15 n° 1 - from Volume gneisses and agmatitic amphibolites. The fi rst step of the margin evolution is traced back The granodiorites occur in aphophyses 4-5 km wide to the Devonian, when the peritidal platform of the (Kishmanja, Ishkarwaz) and in thrusted sheets and Chimarabad Formation emerged (Givetian?) and slices, 4 to 10 km long (in front of Kan Khun). The was covered by the conglomerates at the base of the granite bears biotite and frequent amphibole, almost Shogram Formation. The Shogram Formation had totally altered. According to the Debon and Le Fort a sedimentation rate of 10/15 m/My. Upwards, the classifi cation (1988), the granitoid is a dark-colored terrigenous input becomes abundant with spells of

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 5-SyntethiccolumnoftheNorthernKarakoram sedimentarycover (fromGaetani1997,updated). 24-05-2004, 15:53:43 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Figure 6 - Stratigraphic scheme of the Devonian to Permian formations along the transect from the Karambar unit to the Axial metasediments. (from Gaetani et al., 2004).

coarser arenites (Margach Formation). The sandstone deeper basin with fi ne pelagic cherty limestones. petrography indicates that sedimentation was The passive margin succession is covered by Liassic accompanied by tectonic uplift of metamorphic rocks orogenic sandstones with clasts of serpentinites, in the source area. It can be related to the onset of radiolarites, basalts and paragneiss, suggesting the rifting, with a sedimentation rate which may reach 30 erosion of a nearby, newly-formed orogenic wedge m/My. Widespread occurrence of transgressive shelf (Gaetani et al., 1993). During the Cretaceous, the limestones and marls, particularly rich in crinoidal Karakoram suffered severe deformation combined ossicles, seals this initial rifting event. with intensive plutonic activity. Folds and thrust sheets The rest of the Carboniferous is known only in are sealed by mid-Cretaceous molassic conglomerates the Karambar Unit. The arenites of the Lupsuk (Reshun Fm., Tupop Fm.), and by the U. Cretaceous Formation document active volcanism, also recorded (Campanian) marine Darband Formation (Gaetani et by interbedded microlithic spilites. In addition to the al. 1993). This event records the fi nal accretion of petrographic evidence, the erosion and gentle tilting Kohistan to the Karakoram. of the Carboniferous succession in the Baroghil- Lashkargaz Unit and the general trend along the Structure of the Northern Karakoram. transect, actually point to a major rifting stage, The Northern Karakoram, consists of a thick and where rift shoulders were uplifted and eroded and polyphase stack of thrust sheets which lay north of the the unroofi ng of basement rocks was continuous. The Karakoram Batholiths (Le Fort and Gaetani 1998). sedimentation rate was around 15 m/My. In the Hindu Raj Range, the southern boundary The generally widespread occurrence of the Gircha of the Northern Karakoram is generally tectonic Formation, even if its onset was gradual, seems to and consists of a high-angle reverse shear zone defi nitively seal the previous syn-rift succession. with oblique and left-lateral components, passing Therefore, we proposed to draw the break-up to a south-dipping north–vergent thrust plane in Volume n° 1 - from PRO1 to B15 n° 1 - from Volume unconformity within the lower part of the Gircha the Chiantar glacier area. Slices of the Cretaceous Formation (?latest Carboniferous - Asselian in age) batholith are tectonically included within the cover, as (Gaetani et al. 2004). (Fig. 7). well as deformed metasediments which occur along the main tectonic boundaries among the intrusive The sedimentary succession continued during the units of the batholith. Intrusive contacts are, however, Permian and Triassic, with articulated sedimentation locally preserved. settings, including carbonated shelf and ramps, and A major subdivision is marked by the Reshun

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan (from Gaetanietal.,2004). Figure 7-Cartoonofthegeometricrelationshipsbelow thebreak-up unconformity sealedbytheGircha Formation. by avery low grademetamorphism. metasediments). Mostoftheseunitswereaffected fossil evidence (Axial Unit, Dobargar-Kotalkash Paleozoic sediments withreducedthicknessandpoor include thepre-Ordovician crystallinebasementand (Fig. 8).Southofthisfault tectonicunitslocally in theeast,over adistanceexceeding 200km 2000), whichconnectstotheUpperHunzaFault Fault ofChitral(Pudsey 1985;Zanchi etal.,1997, boundary above theseunits,withthicknessvarying Reshun Formation occurswithanunconformable Figure 8-LateralextensionoftheReshunFault intheNorthernKarakoram (fromZanchi etal.,2000,modifi

The Cretaceous basalts apparentlyinterbeddedwithcarbonaticrocks. bounded bythe Tash Kupruk Unit,whichconsistsof longitude ofMorich,thisthrustsystemistectonically Group. West oftheBaroghilPass toChitral, up tothe within theOrdovician-? SilurianslatesoftheBaroghil 20 -30km(Fig.9).Mostofthefl of imbricatedthrustsheetslaterallyextending upto successions areexposed, formingacomplex stack Reshun Fault, where Paleo-Mesozoic sedimentary No pre-Ordovician rocksoccurnorthofthe from afew tenstohundredsofmeters.(Fig.8) oor thrustsoccur 24-05-2004, 15:53:55 ed) A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Figure 9 - The main thrust sheets in the Northern Karakoram (From Gaetani et al. 2004, modifi ed).

To the north of the Tash Kupruk outcrop the Shah and Lashkargaz. It consists of a Ordovician to Jinali Phyllites, including a monotonous succession Jurassic succession about 4-5 km thick (Gaetani et of greenschist facies quartzite-bearing metapelites, al., 1996). It is bound to the south by the Axial Unit garnet-chlorite and chloritoid-chlorite phyllites. through a complex system of reverse-oblique faults including conglomerates of the Reshun Formation From the eastern Chitral to the upper reaches of and intensively deformed marble slices. The central- the river Karambar, thrust sheets mostly consist of southern part of this unit is poorly deformed, showing Paleozoic successions, the youngest sediments being continuous sedimentary successions. On the contrary, Early Jurassic in age. On the contrary, along the its northern boundary is intensively deformed, eastern side of the range (Chapursan Valley – Hunza showing E-W trending overturned and recumbent region), thrust sheets include rocks not older than folds and south-vergent thrusts. Permian or possibly Upper Carboniferous (Gaetani et The Karambar Unit extends north and east of the al. 1990; Zanchi and Gaetani 1994). Baroghil-Lashkargaz Unit, between the Chiantar Glacier and southern Wakhan, largely occurring north The main tectonostratigraphic Units north of the of the Pakistani border. This unit will be observed in Reshun Fault are as follows. the distance looking northward and eastward from the The Lasht Unit, which east of the Shah Jinali Pass the Baroghil region. It is mentioned here as it contains hanging wall of the Reshun Fault consists of Devonian the most complete and thick Paleozoic succession of to Permian and possibly Mesozoic carbonatic to the area. The southern sector of the Karambar Unit is terrigenous successions. E-W trending folds and faults extremely folded and abruptly cut by the Reshun Fault. make the structural setting very complex, especially in The unit is split by a large NNE-SSW trending tear

the Siru Gol area, where the unit is intensively sliced fault extending from the Chiantar Glacier to the east of PRO1 to B15 n° 1 - from Volume and tectonically repeated. East of Lasht, the Lasht Unit the Karambar Lake with a left-lateral throw of some is tectonically elided by left-lateral NE-SW trending kilometres. The western and northern sectors of the strike-slip reverse faults which form the eastern Karambar unit show NNW-SSE to NW-SE trending continuation of the Reshun Fault. West-vergent folds and thrusts, whereas the eastern The Baroghil-Lashkargaz Unit occurs in the central part shows E-W south-dipping thrust structures. part of the area visited around the Baroghil Pass

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Tirich Gol(Fig.10)(Zanchietal.,1997,2000). the ShahJinaliPass totheBarumvalley acrossthe peridotites, gneisses,andquartzites,extending from It formsanarrow beltofamphibolites,metagabbros, (TMBZ) The Tirich MirBoundaryZone Tirich Mirplutonwhichcrosscutsthebelt. The TMBZ are preserved especiallyaroundtherigidmassof isolated andtectonicallyemplacedbodies.Peridotites with peridotitesandserpentinitesoccurringassmall Karakoram. The TMBZ unitformsa150kmlongbelt, thrusts formingthenorth-westernboundaryof trending left-lateralstrike-slip faults andS-vergent Valley, merging intoacomplex systemofNE-SW Tirich MirFault. The fault extends alongthe Yarkhun Kupruk Unitsareindirecttectoniccontactalongthe Shah JinaliPhyllitesend,andthe Atark andthe Tash East oftheShahJinaliPass, the TMBZ andthe Figure 10-GeologicalmapoftheTirich MirBoundaryZoneandEHinduKush (fromGaetanietal.,2000,modifi Renewed convergence duringtheNeo-Cimmerian Pamir belts. of Karakoram againstthesouthernsectionof Triassic -EarlyJurassicconvergence andassemblage into anintra-Mega Lhasaorogenicbeltrelatedtothe attenuated continentalcrust,subsequentlyinvolved on apassive continentalmargin oralongazoneof a fragmentedcrust-mantleboundarydeveloped either of theperidotites. Therefore, thisbeltmayrepresent sequence mightsuggestasub-continentalcharacter and harzburgites, andcouplingwithadeepcrustal low temperaturesofequilibrationforlherzolites Absence ofanophioliticsequences.s.,relatively reactivation. strike-slip faulting representsitsmostrecentbrittle the TMBZ isaMesozoicstructure,whereleft-lateral relationships withthe Tirich MirPlutonsuggestthat the NWmargin oftheKarakoram block.Crosscutting can beinterpretedasaboundaryzonewhichdefi 24-05-2004, 15:54:03 ed). nes A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

event may be responsible for the fi nal emplacement (Gaetani et al., 1996). It intrudes the Wakhan Slates. and fragmentation of the belt and its coupling with the The Tirich Mir pluton, possibly related to the SW successions of Karakoram and East Hindu Kush. continuation of this belt, consists of porphyritic granites with a biotite Rb-Sr age of 115 ± 4 Ma (Desio East Hindu Kush et al. 1964). The pluton intruded both the East Hindu The East Hindu Kush block is the western continuation Kush and Karakoram belts, as well as the TMBZ. of the Wakhan (Fig. 4, 10). The oldest rocks include Stoping, moderate effects on host rocks, and absence deformed granitoids, possibly Cambrian in age (Debon of internal-external foliation indicate a shallow level et al., 1987), the Qal’a-e Ust Gneiss (Buchroithner of emplacement. Spectacular intrusive relationships 1980), which are always in tectonic contact with the and dyke swarms occur all around the Tirich Mir Paleo-Mesozoic metasedimentary successions. Most pluton except along its southern margin, where of the belt consists of the Paleozoic Wakhan Slates, the granite is partially deformed showing augen which record accumulation of thick terrigenous textures and mylonitic shear zones (Momi gneiss in sediments coming from the Gondwana supercontinent Buchroithner and Gamerith 1986). in highly subsiding rift basins (Gaetani 1997). The very thick and monotonous succession delivered in Field itinerary Chitral and in the Kan Khun Gol only bryozoans and Distances are counted from the beginning of the Great brachiopods of Paleozoic affi nity (Gaetani and Leven Trunk Road, the main crossing where, coming from 1993), although Triassic conodonts may occur at the Islamabad, the road turns right towards Peshawar. top of the unit in Afghanistan (Kafarsky and Abdullah 1976; Buchroithner 1980). Large tectonic slices of DAY 1 carbonate with Late Paleozoic fusulinids occur close Islamabad - Besham. 265 km. to the Afghan border in the upper Kan Khun Gol above the Wakhan Slates, forming a widespread thrust Stop 1.1: sheet extending to the north of the Baroghil Pass. km15 - Nicholson Gap A Permo-Triassic shallow water carbonatic terrigenous (N33°42’15.2”;E072°49’25.5”) succession, the Atark Unit, possibly deposited on Big quarries are exploiting Eocene limestones of the the rift shoulders (Gaetani and Leven 1993) occurs so-called Margala Hills formations. This thrust is the between the TMBZ and the Wakhan Slates. The westward continuation of the Main Boundary Thrust unit records the evolution from a continental/marine (MBT) of the Himalaya, the southern front of the terrigenous plain to a carbonate ramp with fusulinids range that brings older sediments deposited before in the Early Permian, followed by a wide carbonate the Himalayan orogeny over debris eroded from platform in the Upper Triassic. The Atark Unit is the rising mountains (Molasse) and deposited as the locally sealed by a conglomerate similar to the Murree and Siwalik Formations in which many brick unconformable Cretaceous conglomerates of the factories are in activity. Karakoram (Zanchi et al., 1997). The Indian Foreland (also called Sub-Himalaya) Important tectonic repetitions due to thrust stacking is a > 10 km thick sequence of continental and and superposed folds can be observed everywhere in shallow marine molasse sediments fi lling the fl exural the Atark Unit. Large NNE-SSW to NE-SW trending basin that developed along the southern front of recumbent folds often related to SE-vergent thrusts the Himalayan range (Johnson et al., 1982). These and reverse faults suggest dramatic shortening of the sediments occur between the MBT and the Main unit. Overprinting relationships suggest the presence Frontal Thrust (MFT), a complex series of basement- of earlier folds. controlled tear and reverse faults interpreted as the most recent feature of the southward migrating thrust

East Hindu Kush plutonic belt system (Yeats & Lawrence 1984). Bulk shortening PRO1 to B15 n° 1 - from Volume Jurassic to mid-Cretaceous granitoids intrude the East decreases southward, away from the MFT that places Hindu Kush units (Debon et al., 1987; Gaetani et al., the molasse atop fl uvial sediments of the present-day 1996, Le Fort and Gaetani 1998). The Shushar pluton foredeep established upon the basement of Peninsular (coarse grained granite and adamellite), cropping out India. between Lasht and Kan Khun along the eastern fl ank The Main Boundary Thrust is classically taken as of the Yarkhun Valley, bears a K-Ar age of 144 Ma the basal thrust of the so-called Lesser Himalaya,

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan imbricate thrustpileofmid-Proterozoicto a usuallylow-grade of theIndianShield. Precambrian orearlyPaleozoic orogeny onthispart to pebblesofHazaraslates. This confi matrix oftheconglomerateisnotfoliated,incontrast existed atthetimethat Tanaki was deposited. The in thelandscape,shows thatamaturehillylandscape Topography oftheunconformity, whichcanbeseen fl underlying slates,probablydepositedinadebris to brecciaconsistsofangulardebrisfromthe grade PrecambrianHazaraslates. The conglomerate Cambrian conglomeratesrestunconformablyonlow (N34°06’06.6”;E073°10’15.5”) km 89- Tanaki boulders Stop 1.2: Manserah Cityoccupiesafault valley fi dykes (N34°20’54.9”;E073°12’44.9”) km 124-Mansehragraniteand(Permian?) basic Stop 1.3: and-thrust belt. Regional transpressionisresponsibleforthisfold- facing directionsrefl hinges andfl range ofstyleswithmostfoldshaving ratherangular on theMainBoundary Thrust. Folding shows abroad sediments thathave beenfoldedandthrustsouthward observe essentiallyMesozoic(JurassictoEocene) In thedistantlandscapeafterthisstop,onemay the HimalayaMountains. Miocene fl MCT-related nappes.LateOligocenetoEarly either beneathapaleo-forelandbasinor Ma mostoftheLower Himalayarockswerelocated Thermochronologic studiessuggestthatbefore13 Johnson 1982). main HimalayaMountains,tothenorth(Burbank& Himalaya rockunits,recordtheemergence ofthe to earlyMiocenefl Armbruster 1979,Seeberetal.,1981).LateOligocene MBT, withanapparentdipof15 and 20km,whichisinterpretedasthepresent-day defi produced old gneissesand500Magranitoidsthathave epicontinental marinetransgressionon1.5-2.2Ga crust. Cambrianstromatoliticdolomitesrecordthe sequences originallydepositedonIndiancontinental ow or otherrapidlyaccumulatedsubaerialdeposit. ne aplanarzonefromdepthofabout10km

uvial formationsrecordtheemergence of orthogneiss. Focal mechanismsolutions at limbs(kink-like folds).Opposite- uvial formations,restingonLesser

assemblage ofa20kmthick, ect conjugateaxialplanes. ° N(Seeber& rms alate

le with lled Mesozoic

sediments derived fromtheerosionofdeepsoils. Fort etal.1980). porphyritic granitegives anageof516±16Ma(Le type granite). A wholerockRb/Srisochrononthe typically derived frommeltingofcrustalrocks(S- includes cordieriteandtourmaline.Itistherefore defi characterised bylarge K-feldsparcrystalsthat The Mansehragraniteisacoarseporphyritic granite the roadonrighttowards Naramforabout1km. Pass themaincity, and,inthenorthernsuburb, take important contactinthebasementrocks.Note location ofaNSfault, whichisconsideredtobean Instable slopesingneissesdelineatetheapproximate (N34°46’19.2”;E72°56’08.7”) km 214- Thakot Fault Stop 1.5: terraces above thenarrow river channel. valley oftheNandinarKhwar, withitsmany small Battagram city. Then itentersthedeeplyincised The roadgoesthroughthewideandopenvalley of southward Himalayanthrusting. porphyroclasts indicatesouthward shear, attributed to and apliticveins. Asymmetric tailsonK-feldspar orthogneiss containfoliatedandfoldedpegmatitic Strongly foliatedandfoldedorthogneisswith (N34°37’57.8”; E73°05’21.2”) km 181-OghiOrthogneiss Stop 1.4: the recentupliftofarea. My. Sincethesoildidnotslide, itprobablypredates Soil believed tohave developed between20and5 structures inthegranitearepreserved inrottenrocks. replacement ofmaterialhasoccurredsomostigneous relict saproliticsoils,wherevolume forvolume Chattar plainondeeplyweatheredrockandthick pass, thendown andthroughthewide,open,rich Then theroadrisesthroughapineforesttosmall 1989b) but therocksareprobablypolymetamorphic. metamorphism tobeHimalayan(Treloar etal., to amphibolitefacies. Someauthorsbelieve the chlorite, biotite,garnet,staurolite,kyanite isograds) metamorphism increasesnorthward (successively The generallygreenschistfacies, Barrovian break-up ofGondwana. Permo-Trias Panjal formation,whichisrelatedtothe have intrudedthegranite;they possiblybelongtothe metasediments (pelitesandpsammites).Basicdykes ne itsmagmaticfabric. Itsmineralcomposition

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A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

abundance of secondary graphite. Amphibolite facies, biotite-rich and graphitic metasediments with large, north-plunging folds. Road reaches the Indus crossed at Thakot Bridge Amphibolites represent metabasic rocks (basaltic (km 217). dykes?). The gneiss sequence includes a variety of foliated orthogneiss and quartzo-feldspatic layers. Stop 1.6: Pegmatites cut the sequence. km 230 - Besham Gneiss The spectacular yet monotonous pile is exposed on (N34°50’53.4”;E072°58’16.7”) the slopes of the mountain on the other side of the Gneiss and pegmatites pertain to the so-called Besham Indus, looking north. The geomorphology of this Complex. These rocks represent the Precambrian section of the Indus Valley refl ects rapid and recent Indian Shield. Apatite and zircon fi ssion track ages uplift (concave downward slopes). Steep walls have from garnet-schists sampled near or at this outcrop some terraces and a moderate amount of bottom land. are 5.2±1.8 and 19.6±1.9 Ma, respectively (Zeitler Side valleys display knock points. Minor tributary 1985). drainage form hanging valleys suspended 400m or Instable slopes in gneisses delineate the approximate more above the Indus. This morphology is observed location of a NS fault, which is considered to be an further along the KKH, passing the Chaki Police important contact in the basement rocks. Note the station next to PSO Petrol Station at km11. abundance of secondary graphite. View on the Indus, fl uvial deposits in meanders, Stop 2.2: tilted terraces across the river. Torrents and cones are km19 - Dubair Granodiorite - Left to north exit of spectacular. Dubair Township (km 18) (N35°02’36.1”;E072°53’83.5”) Further north along the road (km 252) look across This metagranodiorite (biotite – hornblende) the Indus at a hanging valley created by recent rapid belongs to the Precambrian “Besham Group”. This down cutting of this segment of the Indus faster metadiorite deformed heterogeneously, and displays than side valleys. Eventually stop near the village unfoliated facies with angular xenoliths. The foliation of Shang, @ N34°52’27”;E072°54?07” where a intensity varies from almost none to pronounced into hornblende-biotite granodiorite gneiss yielded a U- mylonitic bands. Pb zircon, upper intercept age of 1864±4 Ma (lower Its U/Pb zircon age is 1858.8 ±7.2 Ma. Zircon and intercept 153±51 Ma, (DiPietro & Isachsen 2001). apatite fi ssion-track ages are 23± Ma and 3.7± Ma, respectively (Zeilinger 2002, PhD Thesis, ETH- Stay in Besham, km 265. Zurich). DAY 2 Stop 2.3: Besham - Dasu. 72 km. km 21 - Indus Suture (N35°02’19.5”;E072°55’18.5”) Besham group metasediments, orthogneiss and Just before reaching Jijal at a sharp bend in the road pegmatites are well exposed at the Besham KKH see mylonitic gneisses belonging to the Indian Shield Bridge. Point 0 is taken in the Besham township, at with metres-scale, NNE-trending folds whose axes the intersection with the road to Swat. are parallel to the mineral and stretching lineation. 5 km farther the KKH turns into a deep side valley Asymmetric structures (in particular tails on K- where the road fords the stream. On the opposite side feldspar porphyroclasts) demonstrate SSE-ward of the Indus a very coarse boulder rim marks the edge shear. of an impressive debris fl ow/avalanche down a steep Walking around the road bend allows us to cross channel, above. slicken-sided serpentinites that mark the Indus Suture. Volume n° 1 - from PRO1 to B15 n° 1 - from Volume Serpentinites, talc-carbonate schists and imbricate Stop 2.1: gneiss lenses are folded around north-plunging folds km 8 - Besham Gneiss (N34°58’24.4”;E072°53’59. and contain WNW-ENE-trending open folds. The 6”) opposite the end of a jeep road on the far side Suture is also exposed on the other side of the Indus of the Indus River and by a house with a white River (panorama, serpentinites on the left bank). defence tower.

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Figure 2.2a

Figure 2.2b Figure 2.2a and Figure 2.2b - Cross-section through the entire Kohistan Island Arc Complex 24-05-2004, 15:54:14 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Stop 2.4: peridotite precludes websterites forming as cumulates km 22 - Bottom Kohistan peridotites in magma chambers. More likely, these rocks and clinopyroxenites have replaced mantle peridotites. The process is a Drive past Jijal town and stop just after the mosque, magma-consuming, metasomatic reaction between on the right-hand side of the road. Tectonic slivers melt and peridotite at P-T conditions close to the of garnet- and plagioclase-free peridotites and a few peridotite solidus. During cooling, interstitial melts pyroxenites, some of the latter containing tiny garnet become saturated in pyroxene (± aluminous and/or crystals, dominate the lowest section. Intracrystalline hydrous phases) and react with olivine to produce strain features and exsolution lamellae in pyroxene secondary clinopyroxene and orthopyroxene (± indicate high temperature deformation. These spinel, amphibole and/or garnet). Depending on melt rocks have undergone little deformation that can be distribution, the reaction results in fertilising the attributed to obduction-related shear. 50 m to the peridotites either pervasively or within pyroxene-rich North of the mosque, a tectonic contact marks the layers (websterites). Websterites with relict olivine actual lower boundary of the Kohistan terrane. Only fl ames record transitional reaction stages whereas a weak north-dipping foliation appears over 200 m olivine-free websterites (± spinel, amphibole and/or above the Indus Suture, but quickly decreases in garnet) are fi nal reaction products whose formation intensity and disappears upward. requires high melt/rock proportions (Burg et al., 1998). Accordingly, and because of the near-solidus Stop 2.5: conditions, this process occurs atop the asthenospheric km 25-26 - Mantle Rocks - 1 km walk along the mantle where melts are refracted, channelled and KKH (N35°03’00.3”; E072°56’56.5”) eventually accumulated along the permeability barrier The road goes through N-dipping, more or less formed by the base of the lithosphere. serpentinised peridotites “interlayered” with pyroxenites. Park about where, across the Indus Stop 2.6: valley to the east, there is a major side stream going km 23 - Mantle/crust transition down its hanging valley with cultivated terraces, and a (N35°04’19.9”; E072°57’55.5”) knick point where the steep current profi le begins. The sharp contact between garnet-hornblende The usually fi ne-grained pyroxenites form cm- to pyroxenites, with metasomatic textures as described m-thick layers in dunites and wehrlites. Chromite above, and the overlying two-pyroxene granulites, schlieren, pods and layers are randomly distributed with well preserved igneous structures (Miller et al., (Jan & Windley 1990). The proportion of pyroxenites 1991), locally displays interdigitations and coincides gradually increases up-section, and we observe with the last occurrence of dunite fl ames in websterites the intermingled occurrence of dunites, wehrlites, and hornblendites. The granulite margin along the subordinate harzburgites, websterites, hornblendites gently dipping contact is fi ne grained; the lower and garnetites. The websterites are coarse-grained and crustal (granulite facies) calc-alkaline garnet-gabbros virtually undeformed. They constitute layers up to a have intruded hornblendites and garnetites attributed few tens of meters thick that gradually predominate to the mantle. This contact is the lower boundary of over peridotites. Dykes of bright-green Cr-diopside the arc crust (i.e. the arc-Moho). At a map scale it is pyroxenites locally build networks below websterite nearly parallel to the pyroxenite-peridotite layering. layers and have welded the country rocks. Similar Walking back a few hundred meters, the upper part of dykes are known only in association with refractory the ultramafi c-mafi c section is comprised of garnet- mantle rocks (Orberger et al., 1995, Varfaly et al., hornblende pyroxenites whose irregular layering 1996), and indicate that the Jijal peridotites represent (cm to several m thick) is marked by variations in the mantle. content of these mineral phases. Wisps of dunite are

A noteworthy feature is the occurrence of elongated found, although their abundance and size decrease PRO1 to B15 n° 1 - from Volume fl ames, streaks and wisps of dunite in websterites. upward. This is further evidence for a derivation of All transitions are observed between i) websterites the ultramafi c-mafi c sequence from upper mantle with a “gneissic” appearance due to the diffuse peridotites modifi ed by pervasive reaction with layering of cm-thick peridotite fl ames through ii) melts. The gradual development of amphibole websterite containing sparse relics of dunite to may be explained by the evolution of volatile-rich, iii) olivine-free, massive websterite. Relict host residual melt fractions that were left after websterite

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PR01 be seen. hornblendite body. Podsoflarge Mg-chlorititecan as enclaves, andhasbeenintruded by alarge al., 1999).Itisintrusive intohornblenditesfound the JijalComplex (Yamamoto 1993; Ringuetteet garnet-rich metagabbroformsthe’crustal’ unitof Walking upfromthecontact,granulitefacies, al., 1995a). cooling peridotites(Bedinietal.,1997,Kelemen et crystallisation andraisedthroughconductively Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 2.8.1-Focal mechanism ofthe28December1974earthquakes inPatan, fromPennington 1979). Main mineralphasesincludegarnet,clinopyroxene, near theseveins, suggestinglategarnetgrowth. concentrations oflarge euhedralgarnetsbothinand veins thatintersect thefoliationarecommon,with been intrudedbyhornblendites.Cogeneticfelsic species. The garnet-gabbroisintrusive into,andhas variations inthemodalproportions ofthesemineral Magmatic layeringislocallydefi gabbro metamorphosedatgranulitefacies conditions. These rocksrepresentamediumtocoarse-grained km 32.5-Garnet Granuliteswithlarge garnets Stop 2.7: ned bybanded 24-05-2004, 15:54:19 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01 Volume n° 1 - from PRO1 to B15 n° 1 - from Volume

Figure 2.8.2. - The 3 sets of shear zones, after Arbaret et al., 2000.

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan high-Al (Al date cooling. 1996) and96±3Ma(Anczkiewicz & Vance 1997) Sm-Nd isochronsat91±6(Yamamoto &Nakamura 0.33 GPa). by fi (750°C, 1.8GPa) toamajordecompressionfollowed switch fromahigh- conditions. This successionofequilibriaatteststoa retrograded underamphibolite-togreenschist-facies Subsequently, theabove assemblageswerepartly facies conditions. kbars) andsubsequentlyre-equilibratedingranulite- probably buried todepthsofmorethan50km(17 fi high changing equilibria thatsuccessively formedinresponseto consist ofamosaicmagmaticandmetamorphic calculations show thatgarnet-bearingassemblages Petrographic observations andgeothermobarometric plagioclase. composition withlow-Ti (TiO yields ahigh-aluminabasalttogabbro-anorthosite A bulk analysisofatypicalgarnet-bearingsample scapolite, apatite,calcite,andbiotiteisalsonoted. Sporadic occurrenceoforthopyroxene, K-feldspar, chlorite, opaqueoxides,spinel,rutile,andtitanite. quartz, epidote,zoisite,clinozoisite,paragonite, amphiboles, plagioclase,withminororaccessory About 1kmafterPatan, roadcutsexpose mechanism).(Fig. 2.8.1). 076, dipping49N(planeofmotionthefocal epicentre depthof15kmonareverse fault striking the magnitude6.0earthquake on28.12.1974,withan The cityisbuilt onamajorlandslide.Itisknown for in thebusy bazaar. Pass Patan cityatkm36,andpossiblyenjoy sometea (Dated gabbro atN35°07’12’’;E 73°01’35’’) along theKKH. km 39-40-Sheared gabbros - 1kmwalk Stop 2.8: of magmaticassemblagesoccurredinthehigh- batches intheuppermantle.Quasi-isobariccooling thickened arc-typecrustorwithinrisingmagmatic a depthinexcess of50km,eitheratthebasea (Ringuette etal.,1998). These conditionsrepresent GPa andtemperaturesbetween12001450°C assemblages startedatpressuresfrom1.8to2.7 Crystallization ofgarnet-bearingmagmatic eld. Accordingly, thepetrologicalarc-’Moho’ was nal coolingattheupper-crustal level (550°C, -T granulitefi P and 2 O 3 =18.87wt%),and An T conditions. eld withoutreachingtheeclogite P quasi-isobariccoolingregime 2 =0.65wt%), 62 normative P , Treloar rocks have beendescribedbyJan&Howie (1981), The petrographyandgeochemistryoftheplutonic same mineralogicalcomponentsasthebulk rock. syn-magmatic differentiation veins containingthe The plagioclase-quartz±am-phiboleveins comprise found inany plutonicbodymayderive frombasalts. further suggeststhatsomeamphibolitexenoliths these rockshave intrudedsediments;theirpresence arc build-up. Rare calc-silicateenclaves implythat (hornblendites, gabbros,tonalites,granitoids)during was inturnintrudedbypartialmeltsofmantleorigin intruded andcover theJijalComplex. This association gabbroic anddioriticdykes andsillsthathave The shearedrocksrepresentthepileofmetamorphic classifi display awidevariety ofstructuresandhave been magmatic fabrics (Arbaretetal.,2000).Shearzones grained, amphibole-richgabbroswithwellpreserved bodies oflittletoundeformed,mediumcoarse anastomosing ductileshearzonesenclosinglensoid of hornblendegrains. The mineralcomposition a magmaticfabric defi Light coloured,coarse-grainedhornblendedioritewith (N 35°10’39“;E73°06’29“) km 54-Diorite Stop 2.9: an unchangedsourceforallmelts. and amounttoanepsilonHfvalue of+14,indicating guide areindistinguishablewithintheirerrorlimits microfractions datedhereandmentionedlaterinthis Initial Hfisotopiccompositionsofalldatedzircon as ametamorphicphasewithinplagioclaseclusters. plagioclase richdomains.Clinozoisiteisgrowing origin. Garnetisintergrown withrutilealong richer coresthatareinterpretedasrelictsofmagmatic al epidote, quartz,apatiteandclinozoisite(Yoshino et composition ishornblende,plagioclase,rutile,garnet, amphibole andquartzsymplectites. The mineralogical Relictic clinopyroxene shows breakdown to dominantly re-equilibratedinamphibolitefacies. et al age of98.9±0.4(U-Pbzircondating,Schaltegger The sub-granulitic.bottomgabbroyieldedaprecise et al.,2002). with MORB-typeisotopiccharacteristics(Schaltegger the arcactivity fromapartiallymoltenmantlesource they representcalc-alkalinemagmasemplacedduring (1993), Yoshino etal.,(1998). All authorsagreethat . , 1998).Someoftheplagioclaseshow anorthite . , 2002). The datedrockshows afabric thatis ed into3sets(Fig.2.8.2). et al . (1990),Milleretal.,(1991), Yamamoto ned bythepreferred orientation 24-05-2004, 15:54:24 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

includes plagioclase, greenish hornblende, quartz and The metamorphic conditions of these crustal units epidote, chlorite, zircon and rutile mantling ilmenite. never exceeded amphibolite-facies conditions. Subhedral plagioclase shows strong saussuritisation. Along the road, look for the dramatic waterfalls and Worm-like graphic intergrowths between epidote and landslides on the opposite side of the Indus River quartz are preserved as primary magmatic texture. from km 61. Outcrops of banded amphibolites contain This diorite was emplaced at 91.8 ± 1.4 Ma (U-Pb numerous shear zones anastomosing around blocks of zircon dating, Schaltegger et al., 2002). Zircon and relatively intact gabbro to diorite. apatite fi ssion-track ages are 28± Ma and 11± Ma, respectively (Zeilinger 2002, PhD Thesis, ETH- Stop 2.11: Zurich). (Fig. 2.9) km 67 – Granite (N35°14’30’’;E073°10’42’’) Outcrops on both sides of a small bridge (tea shops) Stop 2.10: comprise fi ne-grained, banded amphibolites mainly km 57 - Kiru Amphibolites – Kiru Bridge – 500 m derived from volcanoclastic rocks, intruded by walk along the KKH numerous, light-coloured granitic and granodioritic Strongly foliated and banded amphibolites are veins. Granitic and pegmatitic veins are variously comprised of more than 2500m-thick interlayered and foliated and folded but crosscut the banding of the country Kamila amphibolites. The granite veins also bear variously intense shear fabrics parallel to the regional foliation of the host amphibolites, both with rotated porphyroblasts and asymmetrically folded granite veins denoting intense SW-ward shearing (Treloar et al. 1990) during emplacement, at 97.1±0.2 Ma (U-Pb zircon age; Schaltegger et al., 2002). (Fig. 2.11)

The dated sample was taken ca. 200 m S of the bridge where the Karakoram Highway (KKH) and the Indus River bend sharply towards the E. The coarse grained granodiorite is composed of quartz, plagioclase, muscovite, garnet, euhedral epidote-clinozoisite intergrown with quartz, chlorite, opaque phases, apatite and zircon. Albite rich plagioclase shows weak normal zoning. Orthoclase is strongly sericitized and

Figure 2.9 - Ages after Schaltegger et al., 2002.

magmatically imbricate sills and/or dykes of intensely deformed meta-gabbros and –diorites. Coarse grain amphibolites enclose relicts of gabbros from which they obviously derive. Fine grained, massive and non-banded with metasediments, they possibly have volcanic origin (Jan 1988). The rocks are mainly composed of amphibole and plagioclase with

irregular occurrence of garnet that depends on the PRO1 to B15 n° 1 - from Volume bulk composition (Treloar et al., 1990). The marked shape preferred orientation of amphiboles delineates the mineral and stretching lineation. Rocks of the Kiru Amphibolites intrude the underlying sheared gabbros and diorites of the Patan Complex. They are in turn intruded by the 91.8+1.4 Ma old hornblende diorite. Figure 2.11 - Ages after Schaltegger et al., 2002.

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan strain ofthedeepercrustallevels. into theisland-arc. This isalsoprobablytrueforthe essentially duetoemplacementofdifferent intrusions plutonic unitssuggeststhatregional deformationis deformed volcano-sediments andundeformed transition toconstriction. The alternationofstrongly Intense vertical crenulationinplacesmarksthe to ahighfl metasediments andassociatedmetavolcanites points absence ofsystematicallyasymmetricstructuresinthe and pronouncedmineralorroddinglineationthe associated gabbrosandtonalites. The lackofastrong boundary withtheintrusive Chilasgabbronoriteand during contactmetamorphismalongtheirnorthern The Kamila Amphibolites werestronglydeformed dioritic composition. They have beenintrudedbycoarsergraineddykes of are interlayeredwithcalc-silicatelensesandlayers. metasediments (basaltictuffs?); they containand interpreted asvolcanic andvolcanoclastic Km 72. Dasu, bridgeontheIndusRiver, Visit theBazaar. amphibolites. but theintrusions crosscut thebandingofcountry shows perthiticexsolution. Narrow sheetsarefoliated (stage 2). melts (gabbronoritetogranitoiddykes) duringrifting The wholecomplex was againpenetratedbymantle Look atthenarrow entranceofthe Kandiavalley. Pegmatite withhuge amphiboles. from themaingabbronoritetonorth. intruded theKamilametasediments,tosouth, separating dioritesandhornblende-gabbrosthathave In frontofthemouthKandiariver. Fault zone (N35°26’36.3”; E073°13’08.9”) km 24-walk1kmuptheroad -Contact Stop 3.2: The toplevel, theKamila Amphibolites (N35°17’42.9”;E073°12’33.7”) km 5-Metasediments Stop 3.1: Point zeroistaken atthebridge. Dasu -Chilas.132km. sequence offi to tonaliticcompositions,whichhave intrudedintoa sequence ofvarious plutonicbodieswithgabbroic attening componentduringdeformation. nely banded,fi DAY 3 DAY 3 ne grainedamphibolites s.s. isa Coward and stretchinglineation.Layersarelocallygraded. of thegabbronoritecarriesanearlydown-dip mineral The principallysteepfoliationandmagmaticlayering occasionally zoned. mineral. Rarezirconsaremainlyanhedralandonly 60) withpericlinetwinning.Magnetiteisaccessory Bigger grainspreserve anorthiterichplagioclase(An subordinate biotitefl clinopyroxene. Plagioclaseisoftensaussuritizedand exsolution lamellae. Amphibole ispartlyreplacing Clinopyroxene islesswellpreserved, but alsoshows with incipientspinelgrowth duringcooling. orthopyroxene shows exsolution-lamellae biotite, zircon,magnetiteandilmenite.Magmatic orthopyroxene, amphibole,plagioclase,quartz, The gabbronoriteiscomposedofclinopyroxene, has beenproducedinnarrow andraremylonites. due toeithertectonicormagmaticdeformation hornblende-rich pegmatite dykes. Intensefabric Gabbro-norites displayamagmaticfabric cutby E073°54’35.8 workers); ChilasGabbronorite N35°29’07.3”; km 31(marker 324nearmonumenttoKKH Stop 3.4: Those orsimilarpegmatites yielded amphiboles, lateproductsoftheChilasgabbronorite. Pegmatites withsometensofcentimetreslong Pegmatites Stop 3.3: 80-90 Ma(D.Rex 1985inCoward Figure 3.4-NumericalagesafterSchaltegger etal.2002. etal. (Coward etal.1987)notedthatfacing akes show alterationtochlorite. et al. 39 Ar- , 1987). 40 Ar agesof 24-05-2004, 15:54:31 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

directions imply that the Chilas Complex is a large, length of the Complex. Ultramafi c rocks, pyroxenites tight antiform. The axial plane of this antiform is alternating with troctolites and anorthosites. This nearly vertical and runs along the Complex-axis. small body is one of the UMA lenses. The gabbro-norite cooled and equilibrated at 600- Mainly dunites and peridotites with minor pyroxenites 800°C and 6-8 kbar (Bard 1983, Yamamoto 1993). contain lenticular anorthositic impregnations and A Sm-Nd internal isochron yields an age of c. 70 diffuse intrusions of gabbro-norite. Conversely, Ma (Yamamoto & Nakamura 1996), a cooling age angular blocks of peridotite are found in gabbro-norite. consistent with the conventional zircon U-Pb age of These relationships indicate intrusion of ultramafi c 84 Ma (Schaltegger et al. 2002, Zeitler et al. 1980). rocks under subsolidus conditions (with interstitial (Fig. 3.4). The fi ssion track ages are apatite = 7.3±2 liquid) in partially consolidated norites which, in turn, and zircon 16.5±1.5 (Zeitler 1985). have intruded the ultrabasic rocks (Niida et al. 1996), anorthosites troctolites (plagioclase + olivine). Stop 3.5: km 54 - Shatial-Darel Moraine Stop 3.9: (N35°32’02.4”; E073°28’20.8”) km 116 - Huder Bridge Stop at the beginning of a wide valley. Across the View of Nanga Parbat. Walk a few hundred meters Indus we can see the middle Pleistocene till left by along the road to see graded layers in gabbronorite. the furthest advance down the Indus of Pleistocene ice. Tills are overlain by valley-fi ll sediments at Stop 3.10: both ends and eroded out in mega ripples produced km 121 - View by jokulhlaups (ice-dam breakout fl oods) in late Best view of Nanga Parbat (if weather conditions are Pleistocene. An ice dam from the Darel valley good) emplaced a huge moraine with fresh landforms on the Overnight at Chilas, km 132. south side of the Indus in the re-entrant valley above Shatial village (PSO petrol station). DAY 4 Chilas - Gilgit. 128 km. Stop 3.6: Point 0 at Chilas Inn Hornblendite – Dam site (N35°30’57.4”;E073°44’48.8”) Stop 4.1: Thick hornblendite dyke cutting layered gabbronorite. km 4-5 - Chilas UMA association - 1 to 2 km walk View of the dam site. along the KKH (from about 800 m after Thak Nulla Bridge Stop 3.7: on Indus: N35°24’39.5”;E074°08’17.1”) km 97 - Chilas Gabbronorite and Landscape - 1 At this point, observe coarse carbonate pegmatite, then km beyond police station at entrance to Khanburi walk the section to observe layered gabbronorite and Valley (N35°29’07.3”; E073°54’35.8”) inter-intrusion relationships with UMA components Clear magmatic layers are due to turbidity currents of the Chilas Complex. Walk may stop on nice gabbro in the otherwise fresh, granular and equant layers @ 35°24’27.3”;E074°08’41.4, in front of gabbronorite. hornblendite body. Observe the landscape till and lake sediments The road goes across a series of ultramafi c bodies plastered against gabbronorite walls, present from the and gabbro norites. Gabbro-norites display late Pleistocene dam at Darel-Shatial. magmatic/cumulitic textures. Ultramafi c rocks show porphyroclastic textures in wehrlites and coarse-grain Stop 3.8: textures in plagioclase-bearing dunites.

km 106 - Turli ultrabasites The contact between peridotites (mostly dunites, PRO1 to B15 n° 1 - from Volume (N35°29’07.3”;E073°54’35.8”) wehrlites and websterites) and gabbro-norites is Khan et al., (Khan et al. 1989) identifi ed two main in places a several meters-thick, steeply dipping rock associations: “the rather uniform gabbro-norite transition zone underlined by strongly metasomatic ... and the more diverse ultramafi c-mafi c-anorthosite rocks, such as hornblende and/or plagioclase (UMA) association”, the latter occurring as a string pyroxenites. Metasomatic aureoles indicate extensive of lenses within the gabbro-norite over the >300km reaction between peridotites and infi ltrated melt,

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan between olivine and“secondary”phases. Dunitesalso granuloblastic rocksshowing textural equilibrium dunite facies arestronglyrecrystallizedinfi amphibole, Al-spinel and Ti-oxides atChilas.Some interstitial impregnation ofplagioclase,pyroxene, - Harzburgites andcoarse-granulardunites,with as relictfl clinopyroxenite dikes atJijalwheredunitesalsooccur Cr-spinel crystals,chromititelensesandCr-diopside - Medium-grainedduniteandwehrlite,withdispersed ultramafi versus asteepandtransitionalcontactbetweenChilas a ultramafi - At Jijalashallow dipping,sharpcontactbetween four-fold: conditions, atdifferent times. These arguments are mantle boundariesthatcrystallisedunderdifferent magmas. However, they representtwo distinctcrust/ between mantlerocksandinfi both complexes displaymelt-consuming reactions 1986). Petro-structuralobservation suggeststhat pressures thantheChilasComplex (Coward etal., granulitic rootoftheKohistan Island Arc athigher The Jijalgarnet-gabbrohasbeeninterpretedasthe scale intrusive diapirs. layers refl Facing directionsdeducedfromgradedgabbronorite Kohistan arc(Khanetal.,1993;Burg etal.,1998). norite. These mantle diapirsindicateriftingofthe served asporousfl interpreted asapicesofintra-arcmantlediapirsthat observations, theChilasultramafi intrusive contacts)andlarge (antiformal)scale a large antiform. To integrate small(reactionaland exemplify thesestages. The cumulatelayersdescribe and olivine xenocrysts ingradedcumulatelayers peridotites, blocksofperidotitesingabbro-norites Steeply dipping,intrusive gabbro-noritelayersin hornblendites andhornblende-plagioclaserichrocks. brecciated andfi fractured, intrudedbymagmadikes andeventually Thereafter, uponcooling,theperidotiteswere indicate hightemperaturereactionalcontacts. clinopyroxene, amphibole, Al-spinel and Ti-oxides of magmapercolationinperidotites. Abundant impregnations ofgabbro-noritearefurtherindication dunites (i.e.tracesofinterstitialmagma)anddiffuse junctions betweenseveral cm-sizeolivine crystalsin consolidated norites.Plagioclaseattriplepoint at high,near-solidus conditionswithinpartially implying thattheultrabasicrockswereintruded c rocksandgabbro-norites. ames inreplacive websterite. ect differently facing margins ofsmaller c-mafi nely dispersedinthegabbro-norite, c sequenceandgarnet-gabbros ow conduitstofeedthegabbro- lrtd volatile-rich ltrated, c ois are bodies c ne-grained was moresilicic. quartz-bearing noritesindicatethatthereactantmelt the spatialrelationshipofultramafi the earlyappearanceoforthopyroxene atChilasand pressures inJijalthanChilas.Ontheotherhand, suggests thatmelt-rockreactionstookplaceathigher Al-spinel, Ti-oxides andamphiboleatChilas. This at Jijal,vs.clino-andortho-pyroxenes, plagioclase, ortho-pyroxenes, Cr-spinel, amphiboleandgarnet - The precipitatedmineralsincludeclino-and xenocrysts inbandedgabbro-noriticcumulates. appear asrelictxenoliths inintrusive noritesaswell fault. Inrealitythemotionisreverse erosion andlandslidingsothatitlookslike anormal active fault trace. The scarphasbeenmodifi scarp thatcutstalusconewithhotspringsalongthe Nearly 1kmafterthebridgetoDrang,view onafault km 47-Fault scarp Stop 4.3: beds arediamictite. Nanga Parbat –Haramoshanticline.Lower Jalipur apparently relatedtodeformationnearthegrowing are inverted intoaNW-SE-trending syncline Early Pleistocene,glacialandglacio-fl km 21-Overturned Jalipur sequence. Stop 4.2: from theIndiancrustrocksofKohistan that separateshigh-grade,tonaliticgneissderived Parbat –Haramosh halfwindow. Itisanactive fault The Raikot Fault isthewesternboundaryofNanga (N35°29’42”; E074°35’14”) km55 -Raikot Bridge Stop 4.5: of Precambrianage,aparttheIndianShield. are high-grademetasedimentsandmetaplutonicrocks strongly alteredgneiss. The NangaParbat gneisses slickensides andfault brecciasinthehangingwall, earthquake. The Raikot Fault isresponsiblefor possibly formedduringthe1841landslide-generating seen inglacialtill. A prominent,3-5mhighfault scarp trace oftheactive Raikot Fault. Slicken sidesmaybe Sulfur-smelling (andtasting)hotspringsdelineatethe (N35°28’49.1”;E074°33’58.0”) km 53-Hotsprings Stop 4.4: Parbat –Haramoshhalfwindow. the Raikot Fault, thewesternboundaryofNanga

uvial deposits uvial and relatedto c rockswith 24-05-2004, 15:54:36 e by ed A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Terrane. The gneisses and associated pelitic and mainly of schists and paragneisses, the intermediate calcareous metasediments, metabasites and granitic- Gashu-Confl uence volcanites, and the top Thelichi pegmatitic veins are strongly retrogressed, chloritised Formation, essentially metasedimentary (Khan et al., and often cataclastic. Probably anastomosing gouges 1996). This succession has been defi ned into the large are frequent and often hydrothermally altered. The “Jaglot” syncline underlined by thick marble layers, dominantly reverse fault has a right lateral strike up in the mountains. This outcrop displays rocks of slip component. Sense of slip criteria indicate NW- the Gashu-Confl uence (strongly deformed pillow directed thrusting of the Nanga Parbat massif onto basalts and pyroclastites) and Thelichi Formations Kohistan. The vertical movement is more than 15 km, (calc-silicate layers are common above the pillowed calculated from the metamorphic recrystallisation amphibolites). These rocks represent relatively depth of the Nanga Parbat gneiss. Fission track dating shallow, supra-crustal levels before intrusion of the in the Nanga Parbat area (Zeitler et al. 1982; Zeitler surrounding “Batholith” (Khan et al., 1994). 39Ar-40Ar 1985) indicates that uplift continues, with removal of ages from this sequence are around 60 Ma (Treloar et about 6 km of rocks from above the Nanga Parbat in al., 1989a). the past 1.3 Myr. Stop 4.9: Stop 4.6: km 90-91 - Confl uence granite - 1 km walk along km 63 - 1841 landslide the KKH (N35°44’54.4”;E074°36’59.8”) Viewpoint on the 1841 landslide. One rockslide at Stop at the monument to three great mountain ranges below Hattu Pir, the peak east of the river, fell in the coming together. December 1840 or January 1841 earthquake (likely The Gilgit River joins the Indus River. on the Raikot Fault which passes under the middle Leucogranite sheets are intrusive into older diorites, of the scarp) from a rock spur of Nanga Parbat. The in turn intrusive into tonalitic gneisses. Looking vertical drop of the rockslide was 1900m, and the north observe similar Kohistan gabbros extensively horizontal transport is 3.5 km. intruded by pegmatite and trondjhemitic sills, which On the west side of the river hummocky topography are the youngest intrusions of the area (ca 30 Ma, is present from debris deposited by the landslide. It Rb/Sr age) (Petterson & Windley 1985). Apatite and overrode a cemented Jalipur diamictite and a younger zircon fi ssion track ages are 4.1±1.8 and 10.6±1.1, unconsolidated sandy diamicton. It dammed the respectively (Zeitler 1985). Indus to a depth of 150-300 m until June 1841 and Note the U-shape of upper Indus valley with lower formed a lake that reached up the Gilgit River to V-shape. the mouth of the Hunza River. As the landslip dam failed the fl oodwaters produced scour marks and Stop 4.10: four megaripples with a wavelength of about 110 m – + a few km - Gilgit metasediments. and an amplitude of 2 to 3 m. This catastrophic fl ood The apparently deepest sediments known in the region destroyed many villages along the Indus and a Sikh are sillimanite-garnet bearing metaturbidites, with army unfortunately camped on the Chach fl ood plain easily identifi ed primary bedding of interstratifi ed near the Attock Bridge. metapelites and metasandstones. They locally are intercalated with calc-silicates and fi ne-grained Stop 4.7: amphibolites that represent basic tuffs and volcanic km70 - View of Nanga Parbat fl ows A south-looking view, weather permitting. Stay in Gilgit, km 128. Stop 4.8: DAY 5

km75 - Jaglot sediments and volcanites Gilgit - Yasin PRO1 to B15 n° 1 - from Volume (N35°38’09.2”; E074°36’34.8”) Metasediments with noticeable abundance of pelites Pay a visit to the several meters-high Buddha carved and calc-alkaline metavolcanites screen the so-called in the rocks, near Gilgit, if there is time. Kohistan Batholith. Non-plutonic rocks screening the “Batholith” are devided into three Formations: The bottom Gilgit formation, which consists

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan above thevillage,visittectonic contacts ages yielded14.6±1.3Ma(Zeitler1985). (Petterson & Windley 1985,1991).Zirconfi older stage1gabbrosanddioritesdatedca.110-90Ma 40 Ma.Basic Stop onstage2granitoidsdatedbetween85and (N36°02’01”;E 074°09’01”) about km21-GranitoidsSEShirot Stop 5.1: turbidites. Walking southeastalong between thelasthouses.Outcropsarecarbonaceous through thevillageandclimbafew meterstothesouth visiting theNorth-Kohistan suture. Walk tothewest Drive reasonablyfast andspendtimearound Yasin eleva-tion 2400m) Yasin –(Resthouse@N36°22’43.1”;E073°19’48.3”, Stop 5.4: structures intherocksthiscountry. defi coarse-grained andcontainsphenocrystsxenoliths This granitoidintrusionoftheKohistan Batholithis (N36°15,020’;E073°41,585’) K-feldspar granite-Jai Bargu Stop 5.3: locally cutthelayers. until theroadreachesmoreplutonites.Basicdykes steeply dippingsequencedominatesthelandscape sequences (Petterson& Treloar 2003). This generally laminated tuffs mayrepresentdistalwater-lain ashfall layered. Somelayersareweaklygradedandthinly The sequenceisusuallywellsortedandregularly amplitude foldswithdominantlynorthward vergence. of NorthernKohistan displaylarge wavelength/ mafi Intruded hornfelsfacies metasediments,thinlybedded (N36°02’01”;E 073°51’02”) Metasediments –ca.5kmwestofSherQila Stop 5.2: facies ofexplosive Strombolian-Vulcanian activity. Walking down, acoarsebrecciarepresentsproximal with nointervening sediments. mostly massive fl beyond alarge coneofscree,where metalavas are metabasalts oftheKohistan batholithcanbereached unconformity ofredsandstonesonplutonitesand reef depositedontovolcanoclastic sandstones. The carbonate richturbiditesandrudist-bearing,in-situ ning themagmaticfabric, whichisconsistentwith ctuffs andvolcanites (includingpillowed basalts) to intermediatecompositionIntruding ows and/orsillsofbasaltandandesite

the water channel, ssion track

between

Stop 6.3: contact toleucocraticgranitewithmafi sandstones; Walk ~350mSandreachanintrusive hornfels. Sequencecontainsconglomeratesand & Treloar 2003).Rocksarelow-grade, garnet-epidote both subaerialandsubaqueousenvironments (Petterson volcanism withdepositionandsedimentreworking in and volcanic agglomeratespointingtoexplosive volcanoclastic sediments(tuffs andpyroclastic layers) The roadcutexposes steeplydipping,gradedbedded (N36°14’38.1”; E073°20’27.2”) Metasediments - West ofKhaltiLake Stop 6.2: View ofintrusive contact few km-Intrusive relationships Stop 6.1: Gupis –Mastuj Stay in Yasin. hill @N36°24’49.5”;E073°20’54.4”. shales over greenshales+myloniticmarbles,walk up- E073°22’39.6”. Seeoneofthesuturecontacts:black and reachKarakoram quartzites@N36°27’29.3”; We candrive tothenorthof Yasin tocrosstheSuture Northern Kohistan Suture. Stop 5.5: granites. these conglomeratesareintrudedbyleucocratic volcanites, slatesandquartzites.Bouldersshow that contain fossils.Otherpebblesarevarious plutonites, south, i.e.theKohistan Terrane. Limestone pebbles Conglomerate bouldersbroughtbytorrentfromthe Conglomerates (N36°10’10.9”;E073°04’43.2”) Stop 6.5: younging directions. Low-grade, volcanoclastic turbiditeswithclear Turbidites (N36°23’11.3”;E073°19’46.5”) Stop 6.4: andesites andandesites. dykes derive frombasalts(locallypillowed), basaltic Steeply dippingamphibolitesintrudedbyleucocratic (N36°11”56.9”; E073°14’38.4”) Metabasalts –Dehimalsuspendedbridge DAY 6 c dykes 24-05-2004, 15:54:39 . A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Anywhere along the road down to Mastuj. Stop 6.6: Black and dark-brown shales, slates with minor Turbidites - W of Shamran quartzites, are better seen in the landscape on (N36°10”47.2”; E072°59’21.1”) opposite side of the river, towards SE. Rocks are Dark green, massive (volcanic) meta-turbidites (meta- low metamorphic grade. Some large lenses of volcanodetritics), local ignimbrites. Amphibolites “amphibolite” probably represent basaltic dykes. with deformed garnet-epidote bearing pebbles, Stay in Mastuj shallow porphyric volcanic dyke cross-cutting the metasediments DAY 7 Long drive with red sediments in landscape. Mastuj - Lasht.

Stop 6.7: Itinerary: Mastuj, Gazin, Dobargar, Shost, Lasht Shandur Pass along the “jeepable” road. (N36°05’17.0”;E072°32’46.1”; elevation: 3725m) Theme: Karakoram Range. The metasediments of the Glacial morphology landscape and tea stop. Intermediate Sedimentary Belt, the KK Batholith and N of the Pass: Kohistan sheared metagabbros and the Reshun Fault. The intinerary is developed along diorites (intruding migmatitic metavolcandetritic the Yarkhun Valley. sediments) S of the Pass: Kohistan volcanosediments, overlain by Moving from Mastuj to the ENE we may observe mafi c volcanites (view to SE). in the distance on the south side of the valley the Intermediate (Darkot) Metasedimentary Belt. In this Stop 6.8: belt three major units have been distinguished within Sheared metagabbros - Above bridge across the Darkot Group (Le Fort & Gaetani 1998). the Mastuj River to Rizhun, (NW of Laspur. N36°03’35.2”; E072°27’10.6”) The Gum formation, which forms the prominent Amphibolite facies rocks of the Kohistan Block. horizon in the landscape. Its apparent thickness Strongly foliated and folded metagabbros are typical exceeds 1000 m and it consists mainly of two of the northern boundary of the Kohistan Terrane. lithologies: Garnet is present in the metamorphic paragenesis. - thin bedded grey dark limestones, often intercalated These rocks are cut by hornblende-quartz-bearing with slates and marls, to build packages of some 50- pegmatites. Host rocks of the meta gabbros are 100 m. On the left side of the Qalandar Gum glacier, amphibolite facies, locally migmatitic volcanoclastic a badly preserved fauna dominated by bryozoans sediments, basaltic tuffs and basalts. and subordinate brachiopods of Permian aspect was found; Stop 6.9: - grey and light grey limestones, sometimes Landscape - View on Rizhun and Gol and the dolomitised, forming the spectacular cliffs of North-Kohistan Suture from little hill above and this belt. They may consists either of thin bedded to the E of the road (N36°04’06.6”;E072°27’02.1”) platy grey limestones packed in thickened layers, S side of the valley: Kohistan metagabbros and more frequently in thick massive grey limestones metabasalts: E side of the valley (from bottom (SE) to and dolostones, rising on the highest crests of the top peaks (NW): Kohistan basalts, fault zone (marked mountains, often deformed in tight folds. Due to by orange bands), red clastics as marker horizon (red this deformation, the thickness is diffi cult to assess, to violet sandstones, shales and conglomerates); few but a fi gure of at least 700 m is not impossible. metres of serpentinites (little pass); grey Karakoram Most important is the fi nding in several places of

limestones, faults (marked by another pass); thick shelled bivalves which may be identifi ed with PRO1 to B15 n° 1 - from Volume Karakoram black slates with minor quartzites in the megalodontids and possibly also with the Lithiotis background group. Also possible rudists were observed. If confi rmed, the Gum formation not only spans from Stop 6.10: the Permian to Triassic, but even Cretaceous beds Shales and quartzites of the Karakoram Block could occur. (N36°14’51”;E072°30’54”) The Barum formation mainly consists of grey dark

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan of theintermediatebelt. mountains, thebatholithintrudesmetasediments the Yarkhun River bed. To theeast,highin in thegorge section; itliesunderthescreeof The Fig. 7.1 Gaetani etal.,1966)andLeFort &Gaetani(1998). batholith complex hasbeenstudiedbyP. LeFort (in 7.1), correspondingtothreedifferent plutons. The the gorges, three typesofgranitoidarepresent(Fig. Batholith. (KB) and brachiopodsrelative tothePermian. village areathisunitcontainsfusulinids,bryozoans silty tofi slates, anddarklimestones,locallyinterbeddedwith The Rawat formationconsistingofsplinterlydark could besuggested.Nofossilshave beenfound. internal folding,but afi have beenobserved. Total thicknessisuncertainfor microconglomerates, but noblackchertpebbles litharenites richinquartz,rarelycontainseamsof with siltstonesandslates. The sandstones,mostly cm-thick beds,oftenamalgamated,intercalated sandstones slightlymetamorphosedin10to50 colored micaceousmaterial.Itsometimesresultsin or fl of clear-colored porphyriticgranite-formingpuffs the outcrop,unitlookslike anirregular mixture presenting conspicuousfoliation. At thescaleof medium-grained tomicrogranulartexture, generally with anirregular scatteringofK-feldsparcrystals,a dark biotite-andamphibole-bearingmonzodiorite The Shulkuchmonzodioriteisaheterogeneous Shulkuch monzodiorite Stop 7.2: the IshpirinGorge, carved mostlyinthe From Gazinthevalley turnstothenorthandweenter Belt. Itwillbeobserved directlylaterintheday. the mostinternalunitofNorthernSedimentary Reshun Conglomerate,whichunconformablycovers red unitmaybeobserved inthedistance.Itis at thetopoflateralvalleys of Vanga andPauer, a On thenorthernsideofvalley, afew kmafterBrep, limestone, verticaly dipping,oftheGumformation. A rareopportunitytotouchthemassive beddedgrey anchimetamorphosed limestonesinfront ofPauer. Stop 7.1: ames ofK-feldspar-rich materialindark- southern contact ne arenitic,dm-thicklayers.IntheDarkot Inthe~9kmlongNSsectionalong ofthebatholithisnotvisible gure between300and500m .

Karakoram fi places, theclear-colored veinlets show acontinuous imbibition-like bandingofthegranitoid.Insome granodiorite. W, andlinked totheadvanced chloritisationofthe schistosity, generallymore extensive towards E- magmatic foliation,mostoutcropspresentapervasive alignment offeldsparmegacrysts. Inadditiontothis generally marked bybiotite,but sometimesalsobythe half-meter microgranular enclaves usuallyacentimeter- toa and oftenzoned. The granodioritebearsabundant megacrysts ofK lighter-colored towards thecenterofbody. The amphibole- andbiotite-bearing(oftenchloritised) and voluminous southwards. The massive granitoidis monzodiorite, becomingprogressively moreabundant dikes andpodsofporphyriticgranitecrosscuttingthe Shulkuch monzodioriteasshown bythenumerous peaks. Along the Yarkun Valley itintrudesthe bone oftheHinduRajrangeandsomeitsmajor The Darkot Pass porphyriticgranite and theShulkuchmonzodiorite. Contact betweenDarkot Pass porphyritic granite Stop 7.3: crinoids, splinteryslate,andmassive whitetoreddish made ofgrey thick-bedded dolostoneswithghostsof to thenorth,areintenselydeformed. The banditselfis the ChikarformationoragainSakirmulgranodiorite or Darkot Pass porphyriticgranitetothesouth,and The rocksonbothsides,usuallySakirmulgranodiorite rocks, almostvertically dipping. a narrow bandofslightlymetamorphic sedimentary metasediments canbeseeninthedistance. They form From thevillageofDobargar theDobargar Dobargar. Landscape. Stop 7.4: paragenesis. quartz-plagioclase-biotite-amphibole-pyroxene The mostmafi NE-SW shearzones,thatareoccasionallychloritised. crenulations, andelsewhere itisshearedalongtiny To thesouth,itissometimesalsorefoldedintotight younger. Foliation isquiteconspicuouseverywhere. is diffuse anditisdiffi contact betweenthetwo different coloredgranitoids cases, smallpegmatitic veins develop. Ingeneral,the partial meltinghadoccurredatthecontact.Inother granitoid, formingasortofrestiticselvage, asif lm ofmicasatthecontactwithdark ≠ inlength.Foliation isalways present, c rock,adiorite,bearsmagmatic ≠ feldspar areafew centimeterslong cult totellwhichgranitoidis

forms theback ≠ -colored 24-05-2004, 15:54:43

A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01 Volume n° 1 - from PRO1 to B15 n° 1 - from Volume

Figure 7.1 - The three plutonic units across the Yarkhun River gorge (from Gaetani et al. 1996, modifi ed).

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan diffi amount ofmovement that hasoccurredalongitis corresponds toazoneofshearing;however, the The northernboundaryoftheKarakoram Batholith occur, soonreplacedbyboudinageddikes ofquartz. granodiorite, afew decimeter-thick graniticdikes sheared metaquartzites. After thelastoccurrenceof tectonic slicesoflaminatedgranodioriteand The northerncontactofthebatholithoccursamidst accompanied byasmallcrenulationcleavage. late foldingepisodewithN50’Etrendispresentand greenschist facies retrogressions.Inseveral places,a the granodiorite,causingwidespreadfoliation,and accompanied byquartzandcalciteveins crosscut and metasedimentaryquartzites.Innumerablefaults meter-thick alternationsofmylonitisedorthogneiss quartzites, fi in contactwiththe”AxialBatholith”,now named named inGaetanietal.,(1996) Axial Unit,because Northern Karakoram sedimentarybeltoutcrops, North ofthebatholith,fi section. One kmwalk alongthejeeproad,toobserve the south oftheShostBridge The sedimentarysuccessionofthe Axial Zone Stop 7.6: tectonisation hastransformedmostofthebodyin biotite-amphibole-pyroxene paragenesis. Very strong mafi veins ofclear-colored graniticmaterial. The most minor amphiboliteintercalationscutbydikes and of fi scale, thegranodioritecontainsabundant xenoliths marbles andquartziticmaterialOntheoutcrop including alarge pinchedrefoldedsynclineof magmatic andtectonicsedimentaryinclusions, microgranular enclaves. Itcontainsnumerous euhedral greenhornblendeandbiotite,abundant scales. The granodiorite,whenfresh,containsnestsof heterogeneous andappearstobeshatteredatall The Shakirmulgranodiorite plutonic bodyanditsnortherncontactcropsout A few hundredmsouthofthevillageSakirmul, Sakirmul Granodiorite Stop 7.5: bank ofthe Yarkhun Valley, oppositeDobargar. The bandstretchesfromtheDarkot glaciertotheright of amphibole-andbiotite-bearinggranodiorite. cult todetermine. c rocksincludeamagmaticquartz-plagioclase- ne-grained psammiticbanded quartzitesand ne

banded limestone,andfracturedslab

and itsnorthern contact. rst thrustsliceofthe

is extremely .

distinguished inthelandscapebut itcanhardly most ofwesternandcentralKarakoram canbe The ReshunFault, amajorstructurerunningthrough along theridgeformingwatershed (Fig.7.3). the cliffs ontheoppositesideof thevalley andruns carbonates andtheReshunFm.isbetterexposed on The unconformitybetweenthePermo-Mesozoic well exposed (Fig.7.2). and theoverlying, shearedReshunConglomerate is displacing thecontactbetweencarbonaticunit the oppositesideofriver, apop-upstructure A few hundredmetersbeforetheShostbridge,on foraminifers have beenobserved. Orbitolina are probablyCretaceousinage,youngerthanthe age assignementcouldbemade,but conglomerates of Shostandintheupper Yarkhun Valley. Nodirect reach several hundredmetresinthicknesslike west The unitisusuallytectonically-thinned,but itmay over sandstonepebbles. The matrixismostlyred. 5 and15cm.Carbonatepebblescommonlyprevail sedimentary rocks,withaverage clastsizebetween Cgl. consistsofmoderatelyroundedpebbles layers arealsopresent. The clast-supportedReshun and redshalesprevail, whilstupwards conglomeratic Shost. Inthebasalpartcoarsereddishsandstones unconformity (max10-15°)isobserved around erosion surface. However, nospectacularangular Chitral (Hayden,1915). At thebasethereisan equivalent oftheReshunConglomerate c) The uppermostunitconsistsofconglomerates, characterize theearliest Triassic. Isarcicella lobata,I.staeschei, I.turgida (2004) foundtheconodonts road trenchtowards thenew bridge,Perrietal., 1995). Inasamplefromthisunit,collectedonthe Permian inage(ChapursanGroup,Gaetanietal., contain arichfauna ofsmallforaminifers,Late South ofShost,darkgrey thick-beddedlimestones massive grey dolostonesanddolomiticlimestones. cliff-forming, several hundredm-thick.Itconsistsof b) A middleunitconsistingmostlyofcarbonate, folding maybepresent. has atotalthicknessofatleast1000m,but isoclinal be referredtotheGirchaFm.(Permian). The unit of non-metamorphosedquartzarenites,probablyto At thetopofthisunitthereareafew tensofmeters a) A unitofdarkgrey slates,greenishwhenaltered. bottom totop. Karakoram Batholith. The successionisasfollows, limestones,sinceclastscontainingthose Hindeodus parvus, , speciesthat 24-05-2004, 15:54:53

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Stop 7.7: The Reshun Fault and landscape on the Lasht Thrust Sheet. Mesoscopic structures related to the fault crop out near the bridge on the south side of the river (Fig. 7.4), suggesting several deformational events. Here the Reshun Fault stacks the Lasht Units carbonates upon the Reshun reddish marls and conglomerates. A complex structural pattern suggests a polyphase deformation along the fault including late-stage strike-slip motions. Isoclinal E-W trending folds with horizontal axes and a vertical axial plane Figure 7.2 - Pop-up structure linked to the Reshun fault. cleavage have been observed around Shost on the right side of the

valley. An S1 cleavage crossing the Reshun bedding

(S0) is kinked by F2 folds and it is also sheared by complex associations of reverse and strike- slip faults. To the north of the villages of Shost and Aliabad a complex pattern of folds and thrusts outcrops, repeating the Paleozoic succession of the Lash Unit and the Figure 7.3 - The unconformable contact of the Reshun Conglomerate on the Permo-Triassic massive carbonates. sheared Tash Kupruk Unit. They are followed by the towering dolostones of the Atark Unit, already belong be observed along the Yarkun valley due to the to the E Hindu Kush Range, in a geological sense Quaternary cover. (Fig. 7.5) Volume n° 1 - from PRO1 to B15 n° 1 - from Volume

Figure 7.4 - Plot of mesoscopic strutures in the Reshun Conglomerate.

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan distance withthe Whakan Slates,consideredas Karakoram CrystallineBasementliesattheshortest in distancethesynclineofKanKhun,where we canobserve theclosure ofthe Atark Unit and Moving fromLasht, inthewideplaintonorth Zirch andKanKhun. About a5-hourwalk. Intinerary. Crystalline basement. its contactwiththeEHinduKush. The Karakoram Theme – Lasht –Kishmanja. Overnight inLasht–CampGrounds. Day 13. will beobserved above Inkipontheway back,the the LashtUnit. The contactwiththeHinduKush units through thepoorlyexposed Paleozoic sediments of The roadcontinuesonthenorthernsideofvalley, The northernboundaryofKarakoram and Onfoot,fromLashttoKishmanjathrough Figure 7.5-GeologicalmapoftheShost-Lashtarea(From Gaetanietal.,1996,modifi DAY 8 separates the TK fromthe Axial Unit. marls andterrigenoussedimentsoftheReshunFm. two fl symmetric repetitionofthesamelayersalong open NE-SWsynformalstructure,enhancedbythe centre the Task Kupruk Unit(Karakoram) formsan intruded bytheShusharporphyriticgranite.In The Wakhan Slatesoutcropontheleftandare Le Fort &Gaetani(1998). may behammered.For detailsandgeochemistrysee complex ofbatholiths.Onlythebouldersinriver of theKarakoram whichpertaintotheEHinduKush slip fault systemscharacterizingthewesternmargin a left-lateralshearzonealongtheENE-WSWstrike- The tectonicboundariesarealmostvertical, forming pertaining totheEHinduKush. (Fig.8.1). on theslope. Zone arenotfar formthetrailandwillbeobserved At thevillageofZirchvolcanics of Tash Kupruk Zirch Stop 8.1: anks ofthemountains. A thinsliceofreddish . Lavas of Tash Kupruk Zone. ed). 24-05-2004, 15:55:14 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Figure 8.1 - Panoramic view of the complex syncline of Kan Khun. Petrographically, the rocks are extremely altered by garnet remaining in the source, thus implying a in a dirty assemblage of quartz-albite-chlorite- deep origin. ≠amphibole-epidote-sphene and opaques, due to thorough greenschist facies recrystallisation. The path continues on the plain. The variability of abundance of the Low-Field≠ Strength Elements (LFSE): K, Rb, Ba, (Sr) and Th, Stop 8.2: refl ects the deep alteration (Le Fort in Gaetani et al., Mesozoic carbonates. 1996). Before Kan Khun we cross the Yarkhun River The less mobile major elements during low grade on the bridge to shortly observe the top of the metamorphism point to an association of alkali carbonate unit, in which a few megalodontids may basalts. In the nomenclature diagram of Debon & Le be observed, allowing us to attribute it to the Upper Fort (1988), although mobilisation of K and also Na Triassic. The carbonates have a small depression have probably shifted the points, all samples plot in fi lled with red shales at the top, relative to the Reshun an alkaline to peralkaline fi eld of basalts to latibasalts. Conglomerate. These alkaline characteristics are supported by the high content in TiO2 (1.32 to 4.44 wt %) and P205 Back on the main trail, we negotiate the crossing (0.7 to 1.8 wt %), both very present in the Mullen of the creeks coming from Kan Khun valley (no alkaline fi eld (1983). They resemble basanites. bridges). When the opposite bank is eventually However, the Mg/(Mg+Fe) ratio is rather low reached, we shall walk up to a saddle. compared to the average of Debon & Le Fort (1988) or to the alkali basalts of Hawaii. Stop 8.3: Trace elements and REE enforce these alkaline Reshun Fault and Karakoram Crystalline features. The high Zr, Nb and La compare well with Basement. the oceanic island basalts (OIB, e.g. Pearce and Norry, The foot path crosses the Reshun Fault. Isoclinal 1979) and other alkali basalts from continental rifting folds in the Reshun Congl. are evident above places (e.g. Barbieri et al., 1975). Very high Cr and the unconformable boundary with the Mesozoic PRO1 to B15 n° 1 - from Volume Ni contents testify to a mantle source. In this line, carbonates. The carbonates are in tectonic contact Th is correlated to Nb with no steady enrichment with a thin slice of the Iskarwaz-type granodiorite, in Th, which would characterize a continental crust which is intruded in the Chikar Quartzites (Le Fort component. REE are abundant, another characteristic et al., 1994). A left-lateral strike-slip shear zone of alkali basalts, but particularly enriched in LREE marks the boundary between the two units. Close E- with a La/Yb ratio of 35 and 38, and with no Eu W trending folds with a well developed axial plane

anomaly. The depletion in HREE can be explained cleavage (S1) occur along the path. The cleavage is

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan defl the NWslopeofKoyo Zom. Figure 8.3-ThemetasedimentsoftheDobargarsliceon several cobblesoftheIshkarwaz granodiorite, camping groundlies. The widedebrisfan contains the shrubsandbarley fi obliged towalk upalongtheslope,todescendlater water level istoohigh,beforeKishmanjawewill be continues onthefl Descending tothebankof Yarkhun River, thetrail streams ontheplain. may beobtained,whilsttheriver formsbraided the KB(Fig.8.3). A superbview oftheuppervalley tectonic slicesseparatingtheChikarquartzitesfrom small spurobserve theDobargar andKotalkash Ishkarwaz-type granodiorite.Fromthetopof The saddleiscarved inasmallapophysisofthe shear zones. Ishkarwaz-type intrusives show NE-SWmylonitic lateral strike-slip fault hasbeenobserved. Also the its westernboundary, whereamajorNE-SWleft- approaching theIshkarwaz granodioritesandalong Left lateralstrike-slip faults canbedistinguished close totheriver (Fig.8.2). is wellrecognizableintheoutcropsalongbeach ected byaseconddeformationalevent (D Figure 8.2.-PlotofmesoscopicstructuresmeasuredintheReshunConglomerateandadjacentrock units. oor ofthevalley. However, ifthe eld ofKishmanja,wherethe 2 ) which River Valley. From Kishmanjathepathcontinuesalong Yarkhun (2-hour walk). basement andtheOrdovician transgressive sediments Pass, toobserve thecontactbetween thecrystalline (4-hour walk). Intheafternoontowards theBaroghil in themorning,wherecampgroundislocated Itinerary - Karakoram. an overview ofthesedimentarycover ofNorthern Theme Kishmanja –IshkarwazBridge Overnight inKishmanja. cropping outonthetowering wall. After thebridge,pathgraduallygoesuptowards ice-fall. erodes thesnoutofglacier, causingoccasional connection tothe Yasin Valley. The Yarkhun River Raj andthevalley leadingtotheDarkot Pass, main Koyo Zom(6871m),thehighestpeakofHindu Imposing view ofthemainrangewith thetowering photograph stop. Before thebridgeon Yarkhun River - Stop 9.2: and quartzitessuggesttheoccurrence A few hundredmetersfromKismanaja,spottedslates marks andgradedbeddingmaybeobserved. where occasionallysedimentarystructures,like ripple The sparseoutcropsareallintheChikarQuartzite, Chikar Quarzite. Stop 9.1: small apophysisoutcropsnearby. aureola aroundtheIshkarwaz granodiorite,ofwhicha – The Karakoram Crystalline Basementand FromKishmanjatotheIshkarwaz Bridge DAY 9 ofa 24-05-2004, 15:55:33 contact A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

the village of Chikar. Close folds in the quartzites and upper transgressive contact with a conglomeratic huge shear zones occur before reaching the Ishkarwaz sandstone. The transgressive arkoses and slates granodiorite. contain a fairly rich assemblage of acritarchs of Arenigian age (Early Ordovician), belonging to the Stop 9. 3: Peri-Gondwana biogeographic province (Le Fort et Saddle Chikar-Ishkarwaz. al., 1994; Tongiorgi et al., 1994; Quintavalle et al., When on the saddle, a wide panorama on the Baroghil 2000). (Fig. 9.1). area and the Darkot Pass. To the north, the steep slope of the mountain consists of folded Chikar Quartzite The age of the two detected assemblages (CK 1 and intruded by the Ishkarwaz granodiorite. At the top, CK 2) obtained through correlation to graptolite and the black strip corresponds to the Ordovician Yarkhun conodont zones, are reported in Fig. 9.2 Fm. of the Baroghil Group, transgressive on the Crystalline Basement. Return to camp at the Ishkarwaz bridge.

Camp ground near the Ishkarwaz Bridge. Lunch and camping duties. DAY 10 In the afternoon, a walk towards the Baroghil Pass, Vidiakot and Baroghil ridges. the lowest pass of the whole range, from where the Tibetan army entered Chitral and Yasin in the VIII Theme - The Lower Paleozoic succession and the century. structure of the Northern Karakoram. Itinerary – From the camp towards the Baroghil Stop 9.4: Pass and turning West up towards the Vidiakot crest Along the trail sparse outcrops of shattered (4300 m). Later, down towards the Baroghil Pass and Ishkarwaz granodiorite to the ridge to the East, facing the uppermost Yarkhun The Ishkarwaz granodiorite (Le Fort et al., 1994; Le Valley. Fort and Gaetani 1998) is a middle-grained rock that contains biotite turned to chlorite, and amphibole Stop 10.1: almost totally altered. It is classifi ed as a dark- The Yarkhun Formation coloured adamellite, forming an alumino-cafemic The Vidiakot section was measured along the eastern ferriferous asociation with a calc-alkaline affi nity. side of the slope of the main ridge, from 4050 m a.s.l., Enclaves are mainly of microgranular type, but close where the fi rst part of the section in the Yarkhun to the rim of the granitoid, enclaves of quartzite and Fm. is well exposed (locality Purshui) (Fig. 10.1). folded micaschist are frequent. The granodiorite It is notable for its Acritarch content and the intense usually has a dark rusty to purple patina. The whole burrowing of some beds with nice Cruziana trails pluton is severely affected by fracturation; fractures Also a single conodont sample delivered fauna (Talent are often accompanied by millimetre-thick veins of et al., 1981, 1999). Imposing view on the Koio Zom quartz, calcite, chlorite, and sometimes barytine. and the whole Hindu Raj Range. The age of the acritarch assemblages are reported in Stop 9.5: Fig. 9.2. Contact between the Ishkarwaz granodiorite and the Baroghil Group. Stop 10.2: Before the Baroghil meadows the contact crops out Vidiakot Ridge (Le Fort et al., 1994; Tongiorgi et al., 1994). A prominent bed (light coarse sandstone and The contact is fairly fl at, and the granodiorite has no microconglomerates) enables correlation of the

alteration cap. Both the granite and the sedimentary section up to the crest at 4300 m a.s.l. Walking along PRO1 to B15 n° 1 - from Volume series are affected by a foliation dipping some 70° this bed, we climb up to the ridge. The upper limit of to the north, which is greater than the dip of the the Yarkhun Formation is located along the crest, at bedding plane of some 15°. Above the main contact 4305 m a.s.l. (top of bed 13). and the succession described here, there are at least Immediately succeeding the Yarkhun Formation two thrusted slices, of crushed granitic material, are splintery black slates with siltstones nodules or about 25 m thick; the fi rst one has preserved the with very fi ne sandstone intercalations. The intense

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan included. boudins ofPermianlimestoneanddolostoneare the Axial UnitandoftheReshunFault, alongwhich The steepgulley tothe westshows thestructureof (Quintavalle etal.2000). this unittheterm Vidiakot Formation was proposed faulting prevent detailedthicknessmeasurement.For cleavage intheupperpartofthesestrataandsome (from Tongiorgi etal.,1994). Figure 9.1-TheIshkarwaz-Baroghil sectionwithacritarch assemblages with theuppermost Yarkun Valley. the directionofEastRidge,wereachdivide Baroghil Pass. Crossing thetrailtopassgoingin After lunch,wedescendinthedirectionof Northern Karakoram thrustsheets. Baroghil Ridge.Structure ofthe Stop 10.3: 24-05-2004, 15:55:39 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01 Volume n° 1 - from PRO1 to B15 n° 1 - from Volume

Figure 10.1 - The Vidiakot section with the Yarkhun Formation and the acritarch, chitinozoans, and conodont occurrence ( from Quintavalle et al., 2000. modifi ed)

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 10.2-Permian successionintheBaroghilarea(fromGaetanietal.,1995) 24-05-2004, 15:55:49 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Comprehensive view of the structure of the thrust The Chilmarabad Formation consists of two members. sheets. From South to North: Axial Batholith, Axial The lower is made by yellow dolostones with arenitic Zone, Reshun Fault, Baroghil-Lashkargaz Unit, and slaty intercalations. Typical in the basal part are Karamabar Unit. polymictic microconglomerates with clasts of black The Reshun Fault is enhanced by white marble cherts, unknown in the underlying units and the boudins separating the very similar Yarkun group basement. The thickness of this member is 130 m. shales of two different tectonic units. Looking The upper member is made of well-bedded yellow eastward the basal Ordovician shales of the dolostones, locally stromatolitic. In this particular Lashkargaz-Baroghil Unit are stacked above the section, fossils are almost absent, but elsewhere Reshun red marls and conglomerates along a very in the Karambar Thrust Sheet stromatoporoids are steep N-dipping fault planes. Oblique to strike-slip fairly abundant and the age is Middle Devonian. The striations suggesting a reactivation of the fault in a thickness of this member is about 100 m. (Fig. 11.2). transpressional regime occur between the Reshun and the Permian white Fusulinid limestones of the Axial Stop 11.2: Unit. Complex slices of the Paleozoic formations Shogram Formation have been distinguished along this fault system. The trail follows the development of the Shogram Around the area there are sparse outcrops of the Fomation (Fig. 11.3) quartzarenites of the Gircha Fm. (Lower Permian), section Baroghil East, (Fig.10.2). It rests unconformably on the Chilmarabad. The Looking northward the very characteristic Tash basal lithozone consists of coarse arenites and Kupruk lithologies can be distinguished above microconglomerates, deposited in a fl uvial setting. the Paleo-Mesozoic succession of the Lashkargaz Then alternating hybrid sandstones and limestones, tectonic Unit. The Wakhan Slates, overthrusted by locally rich in brachiopods and corals, follow. the fusulinid limestones and dolostones of the Kan Major fossil levels are in the lower part, with corals Khun tectonic Unit form the watershed with the and brachiopods and in the upper part with corals Afghan Ab-i-Panja river (later named Amu Darya), (Schroeder 2004) (Disphyllum cf. caespitosum, fl owing towards Aral Lake. To be noted are the sparse Cyathophyllum afghanense, Pseudopexiphyllum sp., boulders of the Darkot Pass porphyritic granite, up to Hexagonaria sp., Argutastrea sp.) and brachiopods the altitude of 4400 m, indicating an earlier fl owing (Cyrtospirifer sp. and Atrypa sp.) suggesting of the ice-streams into the Amu Darya catchment a Frasnian age. The upper coral level forms a basin. Looking eastward the Lashkargaz area and the baffl estone, 20-30 m thick: a useful regional marker. Chiantar glacier can be distinguished in the distance. A conodont sample (Talent et al., 1999) produced (Fig. 10.3) an early Famennian fauna, dominated by the genus Icriodus. Its position is, however, problematic. Total Back to the camp. Overnight in Ishkarwaz camp. thickness of the formation here is 175 m. Along the river a small outcrop pertaining to the DAY 11 Margach Formation (latest Devonian – earliest The Devonian of the Northern Karakoram Carboniferous) can be observed.

Theme - The Devonian succession. Stop 11.3: Itinerary - Easy walking along the left bank of the View on the Carboniferous section Yarkhun River and back. On the opposite bank of the river, here unfordable, the dark grey crinoidal limestones of the Ribat Formation To the east of Chilmarabad, two slate sheets of the crop out. They delivered a Gnathodus conodont

Baroghil Group are in contact by the Reshun Fault. fauna of late Tournaisian age (Gaetani et al., 2004). PRO1 to B15 n° 1 - from Volume A few tens of m above, the sandstones (well sorted Stop 11.1: arkoses and quartzarenites) of the Gircha Formation Chilmarabad Formation (Permian) directly follow. The Gircha Fm. seals From Baarbun onwards, the trail crosses the Devonian the Carboniferous succession with a feeble angular succession, named in Talent et al., (1999) Yarkhun unconformity. River section (Fig. 11.1). From here back to the camp.

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan 24-05-2004, 15:58:39 Figure 10.3 - Panorama from the Baroghil slopes. A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Figure 11.1 - Geological map of the Baroghil area (after Gaetani et al., 2004 ).

DAY 12 DAY 13 Ishkarwaz - Kan Khun Kan Khun - Dobargar

From the Ishkarwaz camp back on the path along the The journey on foot ends in Lasht, where the jeeps are Yarkhun River. Additional observation and discussion waiting. From Lasht, 3 km drive to Inkip. on the Crystalline basement and the Northern Karakoram structure along the way. Stop 13.1: Volume n° 1 - from PRO1 to B15 n° 1 - from Volume Camp in Kan Khun. Inkip. The Tash Kupruk Zone and the contact with the Hindu Kush If not too tired, observations on the contact between From Inkip to the north, walking up on the left side of Northern Karakoram and E Hindu Kush granitoids the Kaushrao Gol (Fig. 7.4). and Wakhan Slates are possible, walking up about one The fi rst outcrop consists of thick bedded grey hour from the camp ground, along the Kan Khun Gol. dolostones, feebly metamorphosed. They may be locally rich in ooids and oncoliths. Gastropods,

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 11.2-Devonian sectionmeasuredinChitralandUpper Yarkhun Valley (afterTalent et al.). 24-05-2004, 15:56:26 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

chetetids (?), algae, and poorly preserved solitary corals are present amongst the fossils. The age of these rocks is problematic. In Gaetani et al., (1996) they were tentatively attributed to the Devonian. In 2003, D. Vachard, Lille (pers. comm.) identifi ed the sponge genus Cladocoropsis in a few thin sections and suggested Late Jurassic as the age for these rocks. No dolostones are presently known in the Jurassic successions of the Karakoram. These dolostones seems to be associated with the volcanics of the Task Kupruk Zone along most of the outcrops in Pakistani territory. Therefore their age is critical for defi ning the geodynamic scenario and the paleogeography of the volcanic activity. Walking up, a debris scree separates this dolostone outcrop from the following green and violet tuffs and lavas, which are correlatable to the metabasites of Zirch. Up in the mountains, E-W folds affect the low-grade volcaniclastics interbedded with strongly recrystallized whitish marbles. An additional 50 m of thick dark green tuffs and slates follow, then abruptly the marbles of the Atark Unit. Here we cross the boundary between Karakoram and Hindu Kush, represented by the eastern continuation of the Tirich Mir Fault. The structure is a vertical left- lateral strike-slip, and no remnants of the TMBZ have yet been found in this area. Calc-mylonites occur along the boundary in the carbonates of the Atark Unit. A natural section across the boundary is exposed on the opposite site of the deep gorge west of Inkip, where the Tirich Mir Figure 11.3 - The Yarkhun River section in the Shogram Fm.). River Yarkhun 11.3 - The Figure Fault is better exposed (Fig. 13.1). An antiformal structure related to S-vergent thrusting is evident in the Atark Unit; refolded folds can also be distinguished in the core of the antiform in well-bedded marly limestones. The Wakhan Slates can be easily reached in half an hour after crossing the Atark Unit. Back at the jeep, we drive to the springs south of Dobargar. Camp ground. Volume n° 1 - from PRO1 to B15 n° 1 - from Volume DAY 14 Dobargar - Chitral

Till Mastuj the road is the same as day 7. After Mastuj, the road crosses the dark metasiltitites and slates to be refererred to the Intermediate Sedimentary Belt of KK.

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 13.1-Theantiformal structureintothe Atark Unit. 24-05-2004, 15:57:47 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

geochronological study of the India-Kohistan Arc Stop 14.1: collision, Lower Swat region of Pakistan, NW Reshun Conglomerate. Himalaya. Unpublished PhD, # 12771 thesis, ETH. At the tea stall of Parwak, polymictic coarse conglomerate relative to the Reshun Conglomerate. Anczkiewicz, R., Burg, J.-P., Hussain, S. S., Dawood, Here it is very rich in volcanic pebbles, up to 15-20 H., Ghazanfar, M. and Chaudhry, M. N. (1998). cm in size, poorly sorted and with abundant matrix. Stratigraphy and structure of the Indus Suture in the We continue along the Mastuj River. Lower Swat, Pakistan, NW Himalaya. Journal of From Buni to the south, good view of the granitoids of Asian Earth Sciences 16(2-3), 225-238. the Ghamubar Unit. Anczkiewicz, R., Burg, J.-P., Villa, I. M. and Meier, Stop 14.2: M. (2000). Late Cretaceous blueschist metamorphism Kuragh Spur. in the Indus Suture Zone, Shangla region, Pakisatan This locality has been known since Hayden (1915) Himalaya. Tectonophysics 324, 111-134. and Desio (1966). It was designated as a type section Anczkiewicz, R. and Vance, D. (1997). Chronology of the Shogram Formation by Talent et al., (1999). of ,collision and regional metamorphism in Kohistan, (Fig. 14.1) NW Himalaya, Pakistan. Terra Nova, Abstract Supplement 331, 345. The fauna content is rich in brachiopods (Reed 1922, Sartenaer 1965, Vandercammen 1965, Gaetani 1967), Anczkiewicz, R. and Vance, D. (2000). Isotopic corals (Schouppé 1965) and conodonts (Talent et al., constraints on the evolution of metamorphic 1982, 1999). Ages from Middle Givetian to Early conditions in the Jijal-Patan complex and the Kamila Famennian are documented. Belt of the Kohistan arc, Pakistan Himalaya. In: Down in the valley we cross the village of Reshun. To Tectonics of the Nagna Parbat Syntaxis and the the south in the distance good outcrops of the reddish Western Himalaya (edited by Khan, M. A., Treloar, Reshun Conglomerate. From this locality Hayden P. J., Searle, M. P. & Jan, M. Q.). Geological Society fi rst (1915) identifi ed pebbles with Orbitolina in the Special Publication, London, 170, 321-331. conglomerate, fi xing the minimum age for the unit. Stay in Chitral town. Arbaret, L., Burg, J.-P., Zeilinger, G., Chaudhry, N., Hussain, S. and Dawood, H. (2000). Pre-collisional DAY 15 anastomosing shear zones in the Kohistan arc, NW Chitral - Islamabad Pakistan. In: Tectonics of the Nanga Parbat Syntaxis and the Western Himalaya (edited by Khan, M. A., How to reach Islamabad will be decided according to Treloar, P. J., Searle, M. P. & Jan, M. Q.). Geological the situation in the Dir district. Society Special Publications, London 170, 295-311. Bard, J.-P. (1983). Metamorphism of an obducted Acknowledgments island arc: Example of the Kohistan sequence In the last two decades, the plutonic rocks of (Pakistan) in the Himalayan collided range. Earth and Karakoram were extensively studied by P. Le Fort Planetary Science Letters 65, 133-144. and F. Debon, with whom we also shared part of the fi eld work. They are now retired from geology and Bard, J.-P., Maluski, H., Matte, P. and Proust, F. MG tried to summarize some of their outstanding (1980). The Kohistan sequence: crust and mantle of results and to show in the fi eld some of the outcrops an obducted island arc. Geol. Bull. Univ. Peshawar P. Le Fort studied. 11, 87-94.

We also benefi ted from the fi eld guide along the PRO1 to B15 n° 1 - from Volume KKH prepared by R.D. Lawrence and A. Khan for Brookfi eld, M. E. & Reynolds, P. H. 1981. Late the Himalyan-Karakorum-Tibet Workshop, held in Cretaceous emplacement of the Indus suture zone Peshawar, April 1998. ophiolitic mélange and an Eocene-Oligocene magmatic arc on the northern edge of the Indian plate. References Earth and Planetary Science Letters(55), 157-162. Anczkiewicz, R. (1998). Structural and Bedini, R. M., Bodinier, J.-L., Dautria, J.-M. &

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Figure 14.1-ThestratigraphiccolumnofKuragh Spur. (AfterTalent etal.1999) 24-05-2004, 15:57:03 A GEOLOGICAL TRANSECT FROM THE INDIAN PLATE TO THE EAST HINDU KUSH, PAKISTAN PR01

Morten, L. (1997). Evolution of LILE-enriched small Debon, F. (1995). Incipient India-Eurasia collision melt fractions in the lithospheric mantle: A case study and plutonism: the Lower Cenozoic Batura granites from the East African Rift. Earth and Planetary (Hunza Karakorum, North Pakistan). Journal of Science Letters 153(1-2), 67-83. Geological Society of London 152, 785-795.

Buchroithner, M (1980). An outline of the geology of Debon, F. and Khan N.A. (1996). Alkaline orogenic the Afghan Pamirs. Tectonophysics 62, 13-35.. plutonism in the Karakorum batholith: the Upper Buchroithner, M. and Gamerith, H. (1986) On the Cretaceous Koz Sar complex (Karambar Valley, N. geology of the Tirich Mir area, Central Hindu Kush Pakistan). Geodinamica Acta 9, 145-160. (Pakistan). Jharbuch des Geologisches. Bundesanstalt 128, 367-381. Debon, F. and Le Fort, P. (1988). A cationic classifi cation os common plutonic rocks and Burbank, D. W. & Johnson, G. D. (1982). their magmatic associations: principles, method, Intermontane-basin development in the past 4 Myr applications. Bulletin de minéralogie 111, 493-510. in the north-west Himalaya. Nature 298(5873), 432- 436. Debon, F., Le Fort, P., Dautel, D., Sonet, J. & Zimmermann, J. L. (1987). Plutonism in western Burg, J.-P., Bodinier, J.-L., Chaudhry, M. N., Hussain, Karakoram and northern Kohistan (Pakistan): a S. and Dawood, H. (1998). Infra-arc mantle-crust composite Mid-Cretaceous to upper Cenozoic transition and intra-arc mantle diapirs in the Kohistan magmatism. Lithos 20, 19-40. Complex (Pakistani Himalaya): petro-structural Debon, F., Zimmermann, J. L. and Bertrand, J.-M. evidence. Terra Nova 10(2), 74-80. (1986). Le granite du Baltoro (batholite axial du Karakoram, nord Pakistan): une intrusion sub- Chamberlain, C. P., Zeitler, P. K. and Erickson, E. alcaline d‘âge Miocène supérieur. Comptes Rendus (1991). Constraints on the tectonic evolution of the de l’Académie des Sciences de Paris 303 série II(6), Northwestern Himalaya from geochronologic and 463-468. petrologic studies of Babusar Pass, Pakistan. Journal of Geology 99, 829-849. Debon, F., Zimmermann, J.L. and Le Fort, P. (1996). Upper Hunza granites (North Karakorum, Pakistan): a Chaudhry, M. N., Spencer, D. A., Ghazanfar, M., syn-collisional bimodal plutonism of mid-Cretaceous Hussain, S. S. and Dawood, H. 1997. The location of age. Comptes Rendu de l’Academie des Science Paris, the Main Central Thrust in the Northwest Himalaya of IIa, 381-388. Pakistan: Tectonic implications. Geological Bulletin of the Punjab University 31&32, 1-19. Desio, A. (1964). Geological tentative map of the western Karakoram. Scale 1/500 000. Inst. Geol. Coward, M. P., Butler, R. W. H., Khan, M. A. and Univ. Milano. Knipe, R. J. (1987). The tectonic history of Kohistan and its implications for Himalayan structure. Journal Desio, A. (1966). The Devonian system in Mastuj of the Geological Society of London 144, 377-391. valley (Chitral, N.W. Pakistan. Rivista Italiana di Paleontologia e Stratigrafi a,72, 293-320. Coward, M. P., Windley, B. F., Broughton, R. D., Luff, I. W., Petterson, M. G., Pudsey, C. J., Rex, D. Desio, A. and Martina, E. (1972). Geology of the C. and Khan, M. A. (1986). Collision tectonics in Upper Hunza Valley, Karakoram, West Pakistan. the NW Himalayas. In: Collision tectonics (edited Bolletino della Societa Geologica Italiana 91, 283-

by Coward, M. P. & Ries, A. C.). Geological Society 314. PRO1 to B15 n° 1 - from Volume Special Publication, London, 19, 203-219. DiPietro, J. A. & Isachsen, C. E. 2001. U-Pb zircon Crawford, M.B. and Searle, M.P. (1992). Field ages from the Indian plate in northwest Pakistan and relationships and geochemistry of pre-collisional their signifi cance to Himalayan and pre-Himalayan (India-Asia) granitoid magmatism in the Central geologic history. Tectonics 20(4), 510-525. Karakoram. Tectonophysics 206, 171-192.

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan E HinduKush). stratigraphy andfusulinidsfromRoshGol(Chitral, Gaetani, M.andLeven, E.Ja.(1993).Permian Stratigrafi a Pakistan. Permian stratigraphyintheNorthernKarakoram, Leven, E. Y., Nicora, A. andSciunnach,D.(1995). Gaetani, M., Angiolini, L.,Garzanti,E.,Jadoul,F., Geology Asia, fromOrdovician toCretaceous. Gaetani, M.(1997). The Karakoram BlockinCentral Paleontologia eStratigrafi from Chitral.(N.W. Pakistan). Gaetani, M.(1967).SomeDevonian brachiopods Survey ofIndia Gilgit andthePamirs. Hayden, H.H.(1915).NotesonthegeologyofChitral, Society of America Shigar valley, Baltistan,northernPakistan. Hanson, C.R.(1989). The northernsutureinthe Sciences Karakoram (Pakistan). R. (2004). The Carboniferousofthe Western Sciunnach, D.,Brunton,H.,Nicora, A. andMawson, Gaetani, M.,Zanchi, A.,Angiolini, A., Olivini, G., Rundschau Karambar districts(NPakistan). Reconnaissance geologyinChitral,Baroghiland Nicora, A., Sciunnach,D.and Asif, K.(1996). Gaetani, M.,LeFort, P., Tanoli, S., Angiolini, L., Special Publication - Himalayan Tectonics. sedimentary rocks.In: Treloar P. &SearleM.(Eds.) in theNorthKarakorum: ageconstraintsfrom (1993) -JurassicandCretaceousorogenicevents Gaetani, M.,Jadoul,F., Erba,E.andGarzanti 102, 54-62. geopuzzle. - The northKarakorum sideoftheCentral Asia Pasini, M., Tintori, A. andKanwar S.A.K.(1990) Gaetani, M.,Garzanti,E.,Jadoul,F., Nicora, A. , Stratigrafi a 109,339-359. (inpress). 85,683-704. 101,112-158. 99,307-326. Rivista ItalianadiPaleontologia e Geological Societyof America Bulletin 45,271-320. Rivista Italianadi , 74,39-52. Spec.Pap Geological Society. London Records oftheGeological a Journal of Asian Earth 73,3-22. . 232,203-215. Rivista Italianadi

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123-138. Geological SocietySpecialPublication,London, tectonics mature andintra-arcriftstages.In: Pakistan: temporal arcmagmatismthroughearly, - Evolution ofthelower arccrustinKohistan, N. Khan, M. A., Jan,M.Q.and Weaver, B.L.(1993) University ofPeshawar Chilas, northernareas,Pakistan. of aparttheKohistan terranebetweenGilgitand Khan, T., Khan,M. A. andJan,M.Q.(1994).Geology Society of America, Special Paper in theHimalayaofnorthernPakistan. igneous complex: therootofKohistan Island Arc Thirlwall, M.F. (1989). The Chilasmafi Khan, M. A., Jan,M.Q., Windley, B.F., Tarney, J.and Research extraction fromthemantle. in solubleporousmedia,withapplicationstomelt Jordahl, K. A. (1995).Experimentsonfl Kelemen, P. B., Whitehead, J. A., Aharonov, E.and tectonics ofPakistan Kazmi, A. H.&Jan,Q.M.(1997). territories. Nurestan) andrelationshipwiththeadjacent of theNorth-east Afghanistan (Badakhshan, Wakhan, Kafarskyi, A. Kh.and Abdullah, J.(1976). Tectonics 37, 17-42. Palaeogeography, Palaeoclimatology, Palaeoecology Siwalik grouprocksofthePotwar Plateau,Pakistan. Magnetic polarity, stratigraphyandagesofthe Lindsay, E.H.and Tahirkheli, R. A. K.(1982). Johnson, N.M.,Opdyke, N.D.,Johnson,G. Petrology the JijalComplex, NorthwestPakistan. spinel-silicate chemistryinultramafi Jan, M.Q.and Windley, B.F. (1990).Chromian Journal ofMetamorphicGeology angle oftheIndiancontinentalcrustbeneath Asia. pressure metamorphism:sinkingrateandsubduction Shiraishi, K.(2003). Timing ofHimalayanultrahigh- K., Ishikawa, M.,Rehman,H.U.,Kausar, A. B.& Kaneko, Y., Katayama,I., Yamamoto, H.,Misawa, (editedby Treloar, P. J.&Searle,M.P.). 100,475-496. 31(3),667-715. Atti Convegni LinceiRoma . GraphicPublishers,Karachi. 27,99-112. Journal ofGeophysical Geological Bulletin, 21(6),589-599. 232,75-93. 21,87-113. Geology and c ok of rocks c ow focusing ow c-ultramafi Himalayan Geological Journal of 24-05-2004, 15:57:12 74, c

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Khan, T., Khan, M. A., Jan, M. Q. and Naseem, M. Pennington W.D. (1979). Summary of fi eld and (1996). Back-arc basin assemblages in Kohistan, seismic informations of the Pattan earthquake - 28 Northern Pakistan. Geodinamica Acta 9(1), 30-40. December 1974 In Farah A. & Dejong K.A. eds, Le Fort, P., Debon, F. and Sonet, J. (1980). The ‘Lesser Geodynamics of Pakistan, Quetta, Geol. Surv. Pak. Himalayan’ Cordierite Granite Belt. Typology and Perri, M.C., Molloy, P.D. and Talent, J.A. age of the Pluton of Mansehra (Pakistan). Geological (2004). Earliest Triassic conodonts from Chitral, Bulletin, University of Peshawar 3, 51-61. Northernmost Pakistan. Rivista Italiana di Paleontologia e Stratigrafi a 110, (in press). Le Fort, P. and Gaetani, M. (1998). Introduction to Petterson, M. G. and Windley, B. F. (1985). Rb-Sr the geological map of the western Central Karakoram, dating of the Kohistan arc-batholith in the Trans- North Pakistan. Hindu Raj, Ghamubar and Darkot Himalaya of north Pakistan, and tectonic implications. regions. 1:250.000. Geologica 3, 3- 57. Geological Earth and Planetary Science Letters 74(1), 45-57. Survey Pakistan, Islamabad. Le Fort, P., Tongiorgi, M. and Gaetani, M. (1994). Petterson, M. G. and Windley, B. F. (1991). Changing Discovery of crystalline basement and Early source regions of magmas and crustal growth in the Ordovician marine trnsgression in the Karakoram Trans-Himalayas: evidence from the Chalt volcanics mountain Range. Geology 28, 941-944. and Kohistan batholith, Kohistan, northern Pakistan. Earth and Planetary Science Letters 102(3/4), 326- Mason, K. (1938). Karakoram nomenclature. 341. Himalayan Journal 10, 86-125. Petterson, M. G. and Treloar, P. J. (2004). Miller, D. J., Loucks, R. R. and Ashraf, M. (1991). Platinum-group element mineralization in the Volcanostratigraphy of arc volcanic sequences in the Jijal layered ultramafi c-mafi c complex, Pakistani Kohistan arc, North Pakistan: volcanism within island Himalayas. Economic Geology 86(5), 1093-1102. arc, back-arc-basin, and intra-continental tectonic settings. Journal of Volcanology and Geothermal Mullen, E.D. (1983). MnO/TiO2/P2O5: a minor Research 130(1-2), 147-178. element disciminant for basaltic rocks of oceanic environments and its implications for petrogenesis. Pogue, K. R., Hylland, M. D., Yeats, R. S., Khattak, Earth and Planetary Science Letters 62, 53-62. W. U. & Hussain, A. (1999). Stratigraphic and structural framework of Himalayan foothills, northern Niida, K., Kausar, A. B. and Khan, S. R. (1996). Pakistan. Geological Society of America, Special Ultramafi c crystal mush intrusion into crystallizing Paper 328, 257-274. magma chamber: Field evidence from the Chilas Complex, Northern Pakistan. In: Proceedings of Pogue, K. R., Wardlaw, B. R., Harris, A. G. & Hussain, Geoscience Colloquium 15. Geological Survey of A. (1992). Paleozoic and Mesozoic stratigraphy Pakistan, Geoscience Laboratory, 157-171. of the Peshawar basin, Pakistan: Correlations and implications. Geological Society of America Bulletin O’Brien, P. J., Zotov, N., Law, R., Khan, M. A. & 104, 915-927. Jan, M. Q. 2001. Coesite in Himalayan eclogite and implications for models of India-Asia collision. Pudsey, C. J. (1986). The Northern Suture, Pakistan: Geology 29(5), 435-438. margin of a Cretaceous island arc. Geological Magazine 123(4), 405-423. Orberger, B., Lorand, J.-P., Girardeau, J., Mercier, J.- Pudsey, C. J., Coward, M. P., Luff, I. W., Shackleton, C. and Pitragool, S. (1995). Petrogenesis of ultramafi c R. M., Windley, B. F. & Jan, M. Q. (1985a). Collision

rocks and associated chromitites in the Nan Uttaradit zone between the Kohistan arc and the Asian plate in PRO1 to B15 n° 1 - from Volume ophiolite, Northern Thailand. Lithos 35, 153-182. NW Pakistan. Transactions of the Royal Society of Edinburgh: Earth Sciences 76, 463-479. Parrish, R. R. and Tirrul, R. (1989). U-Pb age of the Baltoro granite, northwest Himalaya, and implications Pudsey, C. J., Schroeder, R. and Skelton, P. W. for zircon inheritance and monazite U-Pb systematics. (1985b). Cretaceous (Aptian/Albian) age for island- Geology 17, 1076-1079. arc volcanics, Kohistan, N Pakistan. Himalayan

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan (K et Kuragh (Chitral).ItalianExpeditionstoKarakoram Sartenaer, P. (1965).RhynchonelloideadeShogram 167-168. Geological Bulletin,University ofPeshawar decompression andhydrationofamagmaticarc. northern Pakistan): fromhigh-pressurecoolingto rocks fromtheJijalcomplex (westernHimalayas, Pressure-Temperature evolution ofgarnet-bearing Ringuette, L.,Martignole,J.& Windley, B.F. (1998). Rundschau and Ladakh(N.W. IndiaandPakistan). magmatism acrosstheIndusSutureZoneinKashmir H. (1983). The ageandnatureofMesozoic-Tertiary Reynolds, P. H.,Brookfi pp. and thePamirs. Reed, F.R.C. (1922).Devonian fossilsfromChitral Stratigrafi a Pakistan. chitinozoans fromNorthernKarakoram mountains, (2000). Lower toMiddleOrdovician acritarchsand Quintavalle, M., Tongiorgi, M.andGaetani, Geology Kohistan arccomplex, Pakistan. magmatism: U-PbandHfisotopicevidence fromthe P. (2002).Multiplemantlesourcesduringislandarc Schaltegger, U.,Zeiinger, G.,Frank,M.&Burg, J.- E.J.Brill, Leiden. tectonic evolution ofthecentralKarakoram in Barnicoat, A. 1989.Metamorphic,magmaticand Searle, M.P., Rex, A. J., Tirrul, R.,Rex, D.C.& Karakoram Mountains.358pp., Wiley andSon. Searle, M.P. (1991).Geologyand Tectonics ofthe Leiden. Kush, Scientifi Italian ExpeditionstoKarakoram (K oberdevonische Korallenfauna von Kuragh (Chitral). Schouppé, A. von (1965).Diemittel-bis (in press). Rivista ItalianadiPaleontologia eStratigrafi a the Karakorum Mountains(NorthernPakistan). Schroeder, S.(2004).Devonian rugose corals from 461-468. 2 ) andHinduKush, Scientifi 3,150-168. 72(3),981-1004. Rivista ItalianadiPaleontologia e 106, 3-18. c Reports,IV/1,13-53,E.J.Brill, Paleontologia Indica eld, M.E.&McNutt,R. c Reports,IV/1,55-66, Terra Nova , N.S.,6/2,134 2 ) andHindu Geologische 14(6), 31, 110 vs. basementfaulting. In: the Hazara Arc inNorthernPakistan: decollement Seeber, L.and Armbruster, J.(1979).Seismicityof 929-949. Miscellaneous Publications (1976), sectionIIA, some regional implications. HimalayanSeminar in Chitral(HinduKush). Faunal evidence and P.D. andPickett, J. W. (1982).Intricayoftectonics Talent, J. A., Conaghan,P.J., Mawson, R.,Molloy, Survey ofPakistan, Quetta,125-130. (edited byFarah, A. &DeJong,K. A.). Geological recent dataatplatescale.In: in NorthernPakistan: Synthesisandinterpretationof Tapponnier, P. (1979). The IndiaEurasiaSutureZone Tahirkheli, R. A. K.,Mattauer, M.,Proust,F. & Special Publication,London Treloar, P. J.&Searle,M.P.). N. Pakistan. In: evidence formagmaticarcmigrationwithinKohistan, palaeogeographic reconstructionoftheDirGroup: D., Haynes,J.R.andRex, D.C.(1993). A Sullivan, M. A., Windley, B.F., Saunders, A. Mineralogy (and associatedmetabasites). characterisation ofHigherHimalayaneclogites S. (1995).GeochemicalandSr-Nd isotopic Spencer, D. A., Pognante,U.and Tonarini, S. series, 3,215-242. F.). American GeophysicalUnionGeodynamics Geodynamic evolution Himalayan arc.In: (1981). Seismicityandcontinentalsubductioninthe Seeber, L., Armbruster, J.G.andQuittmeyer, R.C. Survey ofPakistan, Quetta,131-142. (edited byFarah, A. &K.A.,D.J.).Geological Highway transect,northPakistan. Karakoram collisionbeltalongtheKarakoram S. J.(1999). The tectonicevolution oftheKohistan- Searle, M.P., Asif Khan,M.,Fraser, J.E.andGough, Society of America, SpecialPaper, 47-74. Malinconico, L.&Lillie,R.J.)232.Geological In: the Biafo-Baltoro-Husheregions ofN.Pakistan. Tectonics ofthe Western Himalaya 7,89-102. Himalayan tectonics Zagros -HinduKush -Himalaya, (editedbyGupta,H.&Delany, Geological Survey ofIndia, Geodynamics ofPakistan 41,77-101. Geodynamics ofPakistan , 74,139-160. European Journal of Geological Society Tectonics (editedby (editedby 24-05-2004, 15:57:15 18(6),

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Talent, J.A., Gaetani, M., Mawson, R., Molloy, P.D. dating of garnet granulites from the Kohistan complex, and Conaghan P.J. (1999). Early Ordovician and northern Pakistan. Journal of the Geological Society Devonian conodonts from the Western Karakoram and of London 153, 965-969. Hindu Kush, northernmost Pakistan. Rivista Italiana di Paleontologia e Stratigrafi a 105, 201-230. Yamamoto, H. and Nakamura, E. (2000). Timing of magmatic and metamorphic events in the Jijal Tonarini, S., Villa, I. M., Oberli, F., Meier, M., complex of the Kohistan arc deduced from Sm-Nd Spencer, D. A., Pognante, U. & Ramsay, J. G. 1993. dating of mafi c granulites. In: Tectonics of the Nagna Eocene age of eclogite metamorphism in Pakistan Parbat Syntaxis and the Western Himalaya (edited by Himalaya: implications for India-Eurasia collision. Khan, M. A., Treloar, P. J., Searle, M. P. & Jan, M. Terra Nova 5, 13-20. Q.). Geological Society Special Publication, London, 170, 321-331. Tongiorgi, M., Di Milia, A., Le Fort, P. and Gaetani M. (1994). Palynological dating (Arenig) of the Yeats, R. S. and Lawrence, R. D. (1984). Tectonics sedimentary sequence overlying the Ishkarwaz of the Himalayan Thrust Belt in Northern Pakistan. granite (Upper Yarkhun Valley, Chitral, Pakistan. In: Marine geology and oceanography of Arabian Terra Nova 6, 595-607. Sea and Coastal Pakistan (edited by Bilal, U. H. & Treloar, P. J., Petterson, M. G., Qasim Jan, M. Milliman, J. D.). Van Nostrand Reinhold Company, and Sullivan, M. A. (1996). A re-evaluation of New York, 177-198. the stratigraphy and evolution of the Kohistan arc sequence, Pakistan Himalaya: implications for Yoshida, M., Zaman, H. and Ahmad, M. N. (1996). magmatic and tectonic arc-building processes. Paleopositions of Kohistan Arc and surrounding Journal of the Geological Society of London 153, terranes since Cretaceous time: the paleomagnetic 681-693. constraints. Proceedings of Geoscience Colloquium, Geoscience Laboratory Project, Islamabad, Pakistan Treloar, P. J., Rex, D. C., Guise, P. G., Coward, M. 15, 83-101. P., M.P., S., Windley, B. F., Petterson, M. G., Jan, M. Q. and Luff, I. W. (1989a). K/Ar and Ar/Ar Zanchi, A. (1993). Structural evolution of the North geochronology of the Himalayan collision in NW Karakorum cover, North Pakistan. In. Himalayan Pakistan: constraints on the timing of suturing, Tectonics (Ed. by Treloar, P.J. & Searle, M.P.) deformation, metamorphism and uplift. Tectonics Geological Society of London, Special Publication 8(4), 881-909. 74: 21-38.

Treloar, P. J., Williams, M. P. and Coward, M. P. Zanchi, A. and Gaetani, M. (1994) - Introduction (1989b). Metamorphism and crustal stacking in the to the Geological map of the Northern Karakorum North Indian Plate, North Pakistan. Tectonophysics Terrain, from Chapursan valley to Shimshal Pass. 165, 167-184. Rivista Italiana di Paleontologia e Stratigrafi a 100, 125-136, 1 geol. map. Varfaly, V., Herbert, R. and Bédard, J. H. (1996). Zanchi, A., Gaetani, M., Angiolini, L. and De Amicis, Interactions between melt and upper-mantle M. (2001). The 1:100.000 geological map of western- peridotites in the North Arm Mountain massif, central Northern Karakoram terrain (northern areas, Bay of Islands Ophiolite, Newfoundland, Canada: Pakistan). Journal of Asian Earth Sciences 19/3A, 79. implications for the genesis of boninites and related magmas. Chemical Geology 129(1-2), 71-90. Zanchi, A., Gaetani, M. and Poli, S. (1997). The Rich

Gol Metamorphic Complex: evidence of separaton PRO1 to B15 n° 1 - from Volume Yamamoto, H. (1993). Contrasting metamorphic P- between Hindu Kush and Karakoram. Comptes T-time paths of the Kohistan granulites and tectonics Rendues de l’Academie des Sciences Paris IIa, 325, of the western Himalayas. Journal of the Geological 877-882. Society of London 150, 843-856. Zanchi, A., Poli, S., Fumagalli, P., Gaetani, M., Yamamoto, H. and Nakamura, E. (1996). Sm-Nd (2000). Mantle exhumation along the Tirich Mir Fault

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PR01 Leaders: M.Gaetani,J.P. Burg,A.Zanchi,Q.M.Jan Special. Publication,170,237-252. Western Himalayas. - Tectonics oftheNangaParbat Syntaxisandthe M.A., Treloar P.J., SearleM.P. andJanM.Q-(eds.) the Karakoram terranetothe Asian margin. In:Khan Zone, NWPakistan: premid-Cretaceousaccretionof Geological SocietyofLondon , Himalaya, Pakistan. Zeitler, P. K.(1985).CoolinghistoryoftheNW Bulletin, University ofPeshawar from theSwat valley, NorthernPakistan. N. andLyons, J.(1980).Preliminaryfi Zeitler, P.K., Tahirkheli, R. A. K.,Naeser, C.,Johnson, Tectonics 4(1),127-151. 13,63-65. ssion trackages Geological 24-05-2004, 15:57:18 Back Cover: fi eld trip itinerary

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