MOHAMMAD ASHRAF, M. NAWAZ CHAUDHRY and S. SHAHID HUSSAIN

Abstract: Geological mapping of the toposheets (43 B/13 and F/1) carried out shows the fol- lowing rock units in -Kohistan and Allai areas: (1) granitic rds: Lahor granite and associated Shang granite gneiss and Mansehra (Susalgali) granite gneiss (2j Metarnorphics: Thakot group, Tanawal group, Salkhala series, Hazara type slates and dolomitic rocks and amphi'kdites (garnet amphibolite and normal ortho-amphibolites) (3) ultramafics: dunites/peridotites and pyroxenites. Economic mineral deposits found so far are magnetite (in skarns, hornblendites and ultramafics), sphalerite/galena (in skarns, veins and altered granite), chromite (in dunites/peridotites and pyroxenites) and molybdenite (in silicified skarns, altered granites and pegmatites). Anomalous values of Sn, W, Bi, Cd and Mn mineralization have been found in skarns, altered and silicified hhor granite. The skarn type mineralization appears to be associated with the Precambrian Lahor granitic rocks which have intruded into the rocks equivalent to Salkhalas. This granite is. unconforrnably overlain by Hazara type slates and Abbottabad Formation (dolomitic). Two very important structural features have been noted in the area. They are, one older thrust separa- ting Thakot group and associated Lahor granitic rucks and Tanawal group and associated Mansehra granite gneiss. The other very major thrust is the Main Mantle Thrust bringing ophiolite/amphibolite rocks onto Lahor granite, Thakot group, Tanawal group, Mansehra granite gneiss and the Salkhalas.

Previous Work: The area was not studied in detail before the construction of Besharn Kohistan area lies at a distance of about and little attention was paid to geological investigations 150 km. from Abbottabad. The area lies on both sides and exploration. Only the road cuts were studied and of Karakoram Highway. Topography of the area is very checked and no economic mineral was reported from rugged and it has a high relief. The highest peak of the these areas. However, following workers have carried area is at an altitude of 14070 feet at Kabakot whereas out geological investigation in the project area and in the lowest elevation is 1735 feet at Thakot. the surroundings : The project area was poorly studied geologically The western geological region of the project before the present investigation due to poor accessibility. area was studied by Martin, Siddiqui and Topogeological mapping of the project area was carried King (1962). out on the toposheets 43 F/1 and 43 B/13 of the sur- vey of on a scale 1:50,000 to know the gene- Jan and Tahirkheli (1969) described the geo- ral geology and control of mineralization. A total of logy of the lower part of Indus Kohistan. about 500 samples were collected of various rocks, out Jan (1977) studied Kohistan basic complex. of which 70 were studied by incident light microscopy and 30 by reflected light microscopy. 47 samples were Shah (1976) noted the metamorphism and chemically analysed while 60 samples were analysed by pre-existing structures of the section between spectrochemical methods. Thakot and Shatial bridge. Bogio ( 1978) ~eportedmagnetite occurrence The area is very interesting from mineralization in Kohistan area. point of view of magnetite, sphalerite, galena, molyb denite, chromite, copper, cadmium, tungsten, bismuth and Engineers Combine Limited (ECL, 1979) tin etc. Among them sphalerite, galena, chrornite, mag- carried out geological and economic mineral netite and molybdenite are of commercial interest. Fur- investigations in Besham-Kohistan area in ther exploration/investigation work may lead to the detail. This presentation is the outcome of discovery of substantial quantity of other minerals. the same studies. Proc. Intern. Commit. Geodynarnics, Grp. 6, Mtg. , Nov. 23-29, 1979: Spec. Issue, Geol. Bull. Univ. Peshawar, Vol, 13, 1980. the feldspar minerals are dominant and make about 2/3 of the total constituents. At some places silicifi- Igneous and metamorphics are the main rocks cation has taken place resulting in the formation of exposed in the Kohistan-Besham area. Igneous rocks quart. rich rocks. consist of granite, granite gneiss and ultramafics where- as metamorphics are composed of pelitic, psammitic, All these varieties d granite are well jointed. graphitic and calca'reous schists and marbles. Ultra- Weathering is more pronounced along these joints and rnafics are present in the northeastern part of the area weak zones. Magnetite and biotite produce rusty and have thmsted onto Lahor granite/Thakot meta- colour arbund their grains. morphic~,Tanawal Formation, Mansehra granite gneiss and Salkhalas. Amphibolites are exposed further north- Doleritic dykes, pegmatites and quartz veins have eastwards from ultramafics with which they have intruded the granites. Doleritic dykes are greenish faulted contact, black in colour and are 1.5 to 6 m in width and 6 to

' 75 m in length. These dykes are further cut by peg- Igneous Rocks: matite~and quartz veins.

Granites of the area are mainly of three types Pegmatites are from a few mm to 22.5 m in width which are named as Lahor Granite (name after loca- and upto a maximum of 160 m in length. Their occur- lity Lahor, 8 km. to the northwest of Besham), Shang rences are abundant in the screens/migmatised zones Granite gneiss (name after the locality south of Be- than in the granites. The pegmatites are composed of sham) and Mapsehra (Susalgali) granite gneiss (name two coloured (white and grey) microcline (as domi- after the locality near Mansehra) . nant mineral), albite, quartz, biotite, amphibole, tourmaline and write. None of the granite of the project area resembles with that of Swat granite/granite gneiss. Quartz veins are from a few mm to 4.5 m thick and upto a maximum of 90 m inlength. I. Lnkor. Granite: Lahore granite covers about 800 sq. km. of the project area. In the project area Hydrothermal alteration of these granites is a this granite is bounded by the localities Karora, Cha- common phenomenon. This resulted in the introduc- lreser, Thakot , , , Chor Kandao and tion of pyrite, magnetite, chalcopyrite, galena, sphale- Gandori. rite and many other sulphide minerals in these rocks. Quartz and micaceous minerals were found increasing Granite is fine to medium grained and is usually in quantity while epidote and some clay minerals were gneissic. The granite is fine grained near its contact also developed. with country rock, (metasediments and metamorphic screens), however, it is generally medium grained. Apo- 2. Shang Granite Gneiss: This granite gneiss physes are usually present in the bigger screens and ---- seems to be the later phase of Lahor granite exposed are gene~allyfkegrairreck - The -grenits islxomnish --in thevicinitJruf ShngandDubair Bazaz.2~isme grey and grey at weathered surfaces while the fresh dium to coarse grained. Foliation is well developed rocks are greyish white, light grey and grey in colour. and marked by the mineral alignment. Discontinuous Alignment of the black and leuco minerals produces layers of black and white minerals are present. thin discontinuous bands at some places and at places gneissic structure is weakly developed. The granite is also nonfoliated having massive structure at a few Microcline phenocrysts ate about 1 cm long and places. In massive granites the orientation of the mine- 0.5 cm wide. Biotite is concentrated along these phe- rals is random. Intermediate varieties between those noaysts and is dominating bladc minor mineral. two types are also present which show weakly deve- Quartz is in the form of .fine..grains between the feld- loped gneissic structure. Graphic granite was also spar crystals. This granite is further cut by pegmatites obsemed in the Pazang area. The northeastern contact and quartz veins. of this granite is faulted with ultramafics. Usually . . migmatite zone is developed at the contact of granite 3. Mmsehra . (Susalgali) Granite Gneiss: and metamorphic screens. Feldspar crystals and their These .rocks cover about 300 sq. Ism. of the area. aggregates can be easily seen in the metasediments. These are greyish white .to whitish grey in colour and are well foliated. Coarse grained rocks with granitoid Rock cons timents are quartz microcline and texture are also present within these gneissic mcks. clase as essential minerals while biotite and magnetite All these rocks are characterized by porphyroblasts of occur as accessories. These accessories are quite vari- K-feldspar. Detailed studies of these rocks have been able in quantity from place to place. Microcline cfys- carried out on the main mass occurring in Masehra tals are upto 3 mm in longer dimension. ~enerdly and Batgram area by Shams (1969) and Ashraf (1974). TOPOSHEET Nos. L38113 , 43Fll LEGEND

ALLUVIUM

JIJAL ULT RAMAFICS

X U v. x w X v. x'. H X * x - GARNET AMPHlBOLll

G + 4 ", X v. X v. X X CI X - -. KOL*I ANDRAK - + 6, MAHSEHRA ORAUITE X X Cn X v. + CnoR KAHOAO - - p*L*s ANORAK + 977L - s TAHAWAL FORMAT101

SIRBAN DOLOMITE

DOG? CR UAZARA FORMATlOl

MINERALIZE0 SCRB

T HAKOT METASEDIY

SALKHALA FORMATI'

THRUST FAULT

NORMAL FAULT

METALLED ROAD

UNMETALLLD ROAD

DIP I STRIKE

ILONGS.~ 1 2 3 MILES. 5 f f 0 : I I ! - I 1 Fig 1 GEOLOGICAL MAP OF BESHAM - ALLAI AREA I I I I I I I I I000 0 1000 2000 3000 LOO0 5000 so00 M E T R E S Major rock constituents of granitic gneiss are 1. Thakot Metamorphic Rocks: Name is microcline, albite, quartz, muscovite, biotite etc. Peg- given after the locality Thakot. Lahor granite is intru- matite~intruding granites are composed of feldspar, ded in these rocks. These are also present as big quartz, muscovite, tourmaline and also beryl. Expo- screens in the granite along , Khan Khwar, sures of pegmatites are upto a maximum of 13.5 m in Lahor and Pazang. Numerous small sized screens are length and 2.4 m in thickness. present throughout the Lahor granite. Different rock types of the group are as follows: 4. Ultrawafic Rocks: The belt of ultramafic Pelitic-Psammitic Rocks: These are light rocks starts from Dubair/Jijal and extends to Jaba grey, dirty grey and greenish grey in colour and are and Cantor (East of Bannan) in the project area and medium to he grained. Schistosity is well developed. covers about 175 sq. km. These rocks trend in north- Rocks are composed of chlorite, muscovite, 'thtite, west direction, dip towards north and northeast and quartz, feldspar, garnet, pyrite and magnetite. In the cropout near the base of the Kohistan basic complex psammitic rocks quartz is comparatively abundant. Gar- (Tahirkheli et al., 1979). net is prominent at the contact of metasediments and granite due to thermal metamorphism. Psammitic The main mass is composed of dunites, peridotites rocks are predominant among the two rock types. and pyroxenites as alternating layers, which are mas- sive, compact and well jointed. These rocks form Within the psammitic schists, thinly bedded steep slopes along the Dubair Khwar and River quartzites are also present. In the quartzites micaceous Indus. The whole mass is light grey, dirty grey and minerals decrease and the quartz increases compared rusty at weathered surfaces. The occurrence of these with the schists. Both type of schists are recrystalli- rocks has been recorded by Jan (1977) near Jijal. zed and metasornatised. These migmatised zones con- tain higher quantity of feldspar. Dunites and peridotites are light greenish grey Calcareous Rocks and Marbles: Rusty brown to dark grey with greasy appearance. These rocks are coloured rocks at weathered surface are present partially serpentinized. This phenomenon is more pro- in the metamorphics of Thakot. These are from a few minent in the rocks along southern contact. Shearing metres to 75 m thick and upto a maximum of 150 m of the rocks has taken place and serpentinization is long. intense along joints, weak and sheared zones. Serpen- tinites are light grey and brown to dark grey in Calcareous impure beds contain calcite, mica, colour. Dark grey and thin veins of serpentinite are quartz and pyrite. These are jointed and fractured also seen in these rocks. Chrornitite has been found rocks. Most of the calcareous beds in the screens of with these rocks on the basal side as massive lenses granite show contact metamorphism and are minera- and layered bodies. lized. These are changed to skarns, having composi- tion-calcite, siderite, amphibole, pyroxene, garnet, muscovite, biotite, quartz, pyrite and magnetite. Magnetite dissemination is common in peridotites White and greyish white marble bed (containing tre- and dunites and is upto a maximum of 20% in the molite pods) near Dandai is exposed on the roadside. rocks so far observed. These rocks are magnetic in The marble is jointed. character. Graphitic Schists: Graphitic Schists- are Banding and layering in the dunites is commonly interbedded with pelitic-psammitic schists . These are observed. The bands are of light grey, dark grey and upto a maximum of 21 m thick and are well exposed greenish grey colour. This character of rocks is on Resham-Karora and Besham-Lahor roads. These more common in dunites and peridotites. are metamorphosed to a low grade and contain little quantity of graphitic carbon. These schists are thinly Pyroxenites are normally green in colour with bedded and are highly folded and Eaulted. Minerals grey varieties at places. These grey rocks are rich in recognisable in hand specimen are graphite, non-gra- magnetite disseminations. Small sized bodies of lenti- phitic carbon, mica, quartz, feldspar, pyrite and cular chromite have been found in them. ilmenite. Pegmatites and quartz veins have cut these rocks at many places.

Metamorphio Rocks: 2. Tanawal Group: Metamorphics of this group are composed mainly of psammitic schists with very Metamorphic rocks of the area under study are small quantity of pelitic, calcareous and graphitic rocks. composed of pelitic, psammitic, calcareous and graphi- Their characters are almost the same as those of meta- tic schists. Metamorphics can be divided into 4 groups morphic~of Thakot but are of higher grade, ranging and are described briefly in the following: from chlorite to kyanite (Shams, 1967). 3, Salkhalas: Salbalas are composed of marble/ Banding is produced at places by black and calcareous, carbonaceous/graphitic and chloritic schists. white minerals. Black bands are rich in amphibole Graphitic schists are most prominent. whereas feldspar, epidote and quartz make the whiter bands. These rocks are intruded by pegmatites, quartzo- All these rocks are metamorphosed to chlorite feldspathic 'veins and granite porphyry dykes. grade. Garnet is, however, developed near the contact with granite gneiss due to thermal metamorphism.

In the. chlorite schists travertine beds are deve- An area of polymetallic mineralization has been loped in area. These are upto a maximum of found in northern part of Pakistan. The important 3 m long and 1.2 m thick. - These are generally white commercial minerals found are magnetite, galena/ and cream coloured. Bands with light green colour sphalerite and chromite. Anomalous mineralization of occur at a few places. Mo, Sn, W, Cd, Mn, Bi etc. is also widespread. Pos- sibility of concentration of these minerals is likely at 4. Pogra or Hazara Slates and Abbottabad some places. Work carried out is preliminary as far as Formation Dolomite: Near village Renial (east of some of these minerals are concerned. The area needs Karora) a faulted block consisting of Hazara type further detailed investigations as regards geological set slates, graphitic schists and Abbottabad formation up and the anomalous minerals found so far. (dolomitic), is present in the Lahor granite. 1. Magnetite: ~a~nedtehas been found in 5. Metaconglomerates: They are exposed at a skarris, garnet hornblendite and ultramafic rocks. The distance of 6.5 km from Besham on Besham-Karora important occurrences appear to be those present in road. The bed is 9 m thick and contains boulders and skarns and garnet hornblendites. The sizes of the pebbles upto 22 cm in longer direction. These boul- bodies studied are usually small except for a few bo- ders are of slates and granites of Lahor types. This dies in Pazang and Lahor areas. bed is developed between granite and graphitic schists/ slates. Three types of magnetite deposits have been found in the area : I I 6. Amphibolites : Ortho-amphibolite belt of Dir end Swat passes from north of Jijal (Jan, 1977). Along Igneous-Metamorphic Deposim: These are the Indus River these rocks have southern contact associated with Lahor granite and associated metamor- .with ultrabasics. Similar exposures occur in the NE of phics and in mixed rocks of these types. The skarns the mapped area, developed so contian variable quantity of magnetite. Within this type, three varieties of magnetite bearing Generally these rocks can be grouped into two skarns can be distinguished. types : Magnetite-Carbonate skarns: Seventeen samples 1. Garnet amphibolites. of this type were studied petrographically. The rocks are medium to coarse grained and hypidio- 2. Notmal amphibolites . blastic generally. Magnetite varies from 12 to '79% in these rocks. Other minerals are carbona- Garnet amphibolites are massive, coarse-grained tes, olivine, pyroxene and minor amphibole, clay, a.nd gneissic rocks and are exposed to the south of pyrite, antigorite, barite, biotite, apatite and village Pattan and north of and Gantu. sphene. Minor element study of nine samples shows Segregation of minerals is characteristic of Pb = traces to 0.05%, Zn = 0 to 2.0%, Cu = these rocks-resulting in the development of rocks rich 0.002 to 0.03%, Bi = upto O.OlO/o, As = 0.005%, ia one mineral at places. Garnet amphibolites are the , Mo = 5 to 500 ppm, Sn = 0 to 600 ppm and rocks which contain garnet as a major constituent. W = 50 to 400 plpm. Mineral segregation and quantity of garnet decreases b) Siliceous-Magnetite Skarns: Six samples of this north- and eastwards. type were studied microscopically. In this type quartz is the dominant phase instead of calcite. he n&nd amphibolites are gneissic and me- The rocks are medium to coarse grained hypidio- dium to coarse grained. In the project area these are blastic to xenoblastic. Magnetite in these rocks metamorphosed to garnet grade. Rock constituents are varies from 18 to 60% ., Other minerals are amphibole and feldspar as major minerals and quartz, quartz, carbonates, haematite/limonit~, amphibole, epidote, garnet and magnetite as minor and accessory garnet, barite; pyrite, fluorite and epidote: minerals . Minor elements in 'four 'samples are Mo = 0 to 0.01%, Zn = 0 to 0.1%, Pb = 0 to 0.005%, ted on the basis of field observations and structural Mn = 0.01 to 2%, Sn = 0 to 0.01% and W := behaviour of the host rocks. 0.05%. 2. Chromite: Chromite has been discovered in C) Magnetite-Silicate Skarns: Eight samples of this Kchistan district for the first time, It is associated with type were studied petrographically. These are al- the ultramafics (dunites, peridotites and pyroxenites) most completely reconstituted skams. They are of Jijal and Dubair. Chromite is found mainly in duni- generally rich in magnetite i.e. 51 to 96%. Other tes as lenses, layered veins and pockets. It appears to minerals are pyroxene, antigorite, carbonates, be podrform in nature, Their size varies from 0.15 to quartz, haemadte/limonite, amphibole, barite etc. 4 m in width and 3 to 60 m in length. Important Important minor elements are Zn = 0.08%, deposits occur near Jijal, Shungial, Kokial, Taghtai, Pb = 0.005%, Sn= 0.2% and W = 100 ppm. Gabar, Mani Darra, Khairabad, Jag, Tangai, Chinarai, , Serai, Lomoto and Kot. These types occur near village Ghaus Banda, Serai, Shorgar, opposite Kishar, Lahor, Mir Ali, Tor Shah Generally the chromite is medium to coarse- Kandao, Bankhad, Uchkarai, Derai, Pazang, Maidan, grained and is present from 45 to 95% in the rocks. Beshatn-Derai slopes, Masham, Farid Garhi, Darra, The associated minerals being divine, antigorite, chry- Akhunzada Sar (Tapher, Kandora, Darya Sar) BeIa sotile, diopsidic augite, chlorite, tak, magnetite, hema- and Derai (Thakot) and Paiza. tite/Iimonite, spinel, anthophyllite and carbonates. Chemically CriO, = 22.3 to 54.7%, Fep, = 14.74 The magnetite bodies are from a few metres to to 23.4%. Cr/Fe ratio is 1 to 3.62 in these samples. about 250 metres long and a few cm to 45 metres wide. Mining may be carried out by quarrying initially which Inferred reserves of this type of magnetite ore may be followed by underground working at later are of the order of 6.79 million metric tonnes. stages.

Magnetite in Horn bhd2tes: Lenses of Inferred reserves of chromite are 157,260 metric magnetite (3 to 45 metres long and 1 to 14 metres tonnes. wide) occur in hornblendites of garnet amphibolite in the area of Sherakot (Baznai and Gumagali) and 3. Lead and Zinc Mineralization: This mine- Kolai. ralization is associated with Lahor granite and the metamorphic screens exposed in Ghaus Banda, Serai, Concentration of magnetite in these rocks is about Shorgar, opposite Kishar, Kund and Pazang areas of 70 to 75%, while other minerals are amphibole, epi- Kohis tan and Besham. Lead/zinc mineralization is dote, garnet, talc, chlorite, haematite/limonite, pyrite mainly in normal skarns, silicified skarns/veins and etc. altered granites. The size of the mineralized bodies varies from 8 cm to 15 m in width and 1,2 to 84 m Inferred reserves of this type of magnetite ore in length. are 174,200 metric tonnes. Minerals are mainly galena, sphalerite, quar tz, Mtzgnetite ita Ultvabarks: Magnetite occurs pyroxene, amphibole, goethite, albite, pyrite, garnet, in ultrabasics as disseminations and as lenses. The calcite, epidote, biotite, pyrolusite, quenselite, hema- lenses are 1 to 2.4 metres wide and 2 to 6 metres in titellimonite, muscovite, talc, chalcopyrite, colusite length in Lomoto. The disseminations of about 12x45 etc. m area have been found in Kot and Lornoto and at many other places. Chemically, lead ranges from 0.6 to 10.0% and zinc from 1.0 to 8.0% in most of the mineralized Magnetite contents in the rich rocks vary from zones. The are may be produced as a by-product of 78 to 90%. Other minerals are antigorite, olivine, magnetite mining. ' mroxene, talc and spinel. Magnetite in disseminated samples is 15Oh. It is associated with spinel, antigorite, Inferred reserves of the ore are .of the order of olivine, granet etc. 1.08,603 metric tonnes.

The inferred reserves of this type ire 51,323 4. Molybdenum Mineralization: Molybdenum metric tonnes , occurs as molybdenite in areas where lead/zinc mine- ralization is prominent. Mineralization of molybdenite The magnetite deposits are generally well expo- is in three types of rocks. (I) Silicified skarns: It is sed. Their. underground extension can be proved only present in Serai area as disseminated flakes in an area by drilling .and aditing. Geophysical survey also may of about 0.9x7.5 m. The quantity of flakes is less prove helpful. However, the reserves given are calcula- than f % in this zone. (2) Altered granite: This in general has abnormal background values of molybde- ii) Gantar-Talus Fault: The Tanawal group and num. A part of skarn body of Derai/Pazang area is Mansehra granite gneiss have a faulted con- composed of altered granite containing molybdenite. tact with ~alkhala-rocks. The former are Mineral constituents of altered granite are quartz, riding over the latter truncating their western amphibole, epidote, garnet and altered feldspars. Asso- extensions. ciated metallic minerals are pyrohotite, pyrite, galena and sphalerite. Molybdenite occurs as flakes, 0.10 rnnl iii) main Mantle Thrust: The most prominent to 3 mm across. The distribution has no regular pat- and signilkant is the Main Mantle Thrust tern. It is l0/o in rocks at some places. (3) Pegmatites (Tahirkheli et d., 1979) where the Kohistan of Pazang, Derai and Maidan contain a small quantity sequence is overthrusted southwards onto of molybdenite. The maximum size of flakes is 7x23 Lahor granite/Thakot metasediments, Man- CM, sehra granite gneiss/Tanawal metasediments and Salkhalas truncating their north-south A pegmatite-skam zone (300x12 m) contains ran- striking outcrops. domly distributed flakes of molybdenite. Mo in some of the pegmatites, altered granite and calc-skarn varies 3. Magnetite Mineralization is of the following type: from 0.005 to 0.05%, there-by showing an ano- maly in these rocks. i) Magnetite occurrence in skarn and similar rock type is igneous-metamorphic type i.e., 5. Sn, W, Bi, Cd and Mn Mineralization: addition of solutions rich in iron and silica to Anomalous values of these metals have been recorded carbonate rocks. from the Barns, altered and silicified granites of ii) Magnetite deposits in garnet hornblendite Ghaus Banda, p;zang areas and Chain Sar. They have and ultrarnafics are of magmatic segregation maximum Bi (0.8%), Cd (O.Z0h), Sn (0.12%), W type and also as disseminations in latter (100 ppm) and Mn upto 8.0 % . type. 4. Lead/zinc mineralization appears to be mainly CONCLUSIONS :.karn type and at places of hydrothermal origin. 5. Sn, W, Mo, Pb, Zn, Bi, Cd mineralization appear 1. Geologically oldest rocks of the area appear to to fit into vertical zoning pattern (Park and Mac- be Salkhalas. Thalcot metasediments are possibly equi- Diarmid, 1970). Preliminary studies show that Sn, \V valent to Salkhalas or lateral facies variations of the etc., occur at lower elevation; Mo, Pb, Zn, Bi etc,, at same or they are younger than Salkhalas. Lahor gra- moderate elevation while Ag, Hg are found at higher nite has intruded Thakot metasediments. On Besham- elevations. Karora road these rocks have been overlain by slates, possibly of Dogra or Hazara type, having a brecciated 6. Chromite associated with dunite/peridotite is boulder bed at the base. The slates are overlain by possibly magmatic whereas chrornite associated with clolomite bed of Abbottabad type (Cambrian, Latif pyroxenite is perhaps hydrothermal/magmatic as the 1974). From the relationships it appears that the agz chromite bodies are small irregular lenses and swarms. of Lahor granite might be Precambrian. However, this can be confirmed by radiometric dating methods. The younger rocks appear to be of Kohistan sequence and associated ultramafics near the Main Mantle Thrust. REFERENCES

2. Structural history of the area is very complicated Ashraf, M., 1971. Geochemistry akd petrogenesis of acid minor and it will be dealt with in separate publication. There bodies of Mansehra and Batgram area, Hazara. Unpub- are a number of small faults at many places. However, lished Ph.D thesis submitted to the University of the only major faults are discussed in the following: Punjab, Lahore.

i) Thakot-Sakargah Thrust: The younger Tana- E.C.L , 1979. Exploration of magnetite &d other minerals 'in wal Group and Mansehra granite gneiss are AUai-Kohistan. riding over the Thakot met asediment s which ' Jan, M.Q., 1977, &histan basic complex - A summary based has resulted into truncation of the latter north- on recent petrological researchs. Bull. Centre Excell. wards. Geol. Univ. Peshawar. No. 1, Vol. 9-10, pp. 36 42. Across the thrust the metasediments contain Jan, M.Q. and Tahirkheli, R.A.K., 1969. The geology of the distinctly different type of granites and asso- lower part of Indus Kohistan (Swat), West Pakistan. ciated pegmatites. Geol. Bull. Peshawar Univ. No. 1, Vol. 4, pp. 1-13. Latif, M., 1974. A Cambrian age for the Abbottabad Group of Shah, S.H.A., 1976. A brief note on the metamorphism and Hazara, Pakistan. Geol. Bull. Punjab Univ. No. 10, preexisting structures of the section between Thakot pp. 1-20. and Shatial bridge. Geol. Bull. Punjab Univ. No. 12. pp. 105-107. Martin, N.R., Siddiqui, S.F.A., and King, B.H., 1962, A geolo- gical reconnaissance of the region between the Lower Shams, F.A., 1969, geology of the Mansehra-Amb State area Swat and Indus River of Pakistan. Geol. Bull. Punjab N.W. Pakistan. Geol. Bun. Punjab Univ. No. 8, Univ., No. 2, pp. 1-14. pp. 1-20.

Park, C.F., and MacDiarmid, R.A., 1970. Ore Deposits. Tahirkheli, R.A K., Mattaur, M., Proust, F., and Tapponier, W.1-I. Freeman & Co. San Francisco. P., 1979. The India-Eurasia suture zone in Northern Pakistan. In Gedynamics of Pakistan. Geol. Surv. Pak. pp. 125-130.