Distribution of minor elements in the shelf and deep sea sediments of the northern Arabian Sea

ELSEVIER

Marine Chemistry47 (1994) 215-226

Distribution of minor elements in the shelf and deep sea sediments of the northern Arabian Sea D. Satyanarayana, Y. Venkata Ramana Chemical Oceanography Division, School of Chemistry, Andhara University, Visakhapatnam - 530 003, India

Received 18 March 1993;revisionaccepted 14 January 1994

Abstract

Results on the distribution of minor elements (Cu, Ni, Cr, Co, Pb and V) in the surficial sediments of the northern Arabian Sea (latitude 15-20°N, longitude 65-73°30'E) are presented. Based on the texture of the sediments and the distribution of clay minerals, the study area is divided into three regions: (1) the inner shelf, of silty-clay enriched with montmorillonite; (2) the outer shelf, dominated by sand and illite; and (3) the deep sea, consisting of clayey silt. Except for Pb, all dements showed relative enrichment in the inner shelf and deep sea when compared with outer-shelf sediments, in accordance with their texture and grain size parameters. Metal/A1 ratios indicate their occurrences in both lithogenous and non-lithogenous fractions. Most of these elements are detrital in origin and are primarily present in montmorillonite, illite, amphiboles, pyroxenes, garnets, feldspars and ilmrtite. Adsorption on Fe-Mn oxides and incorporation in authigenic minerals, such as anatase, are the other possible sources of these trace elements in the sediments.

1. Introduction

2. Material and methods

Several reports have been published on the bulk and partition geochemistry of minor elements in the sediments of the western continental shelf of India (Murty et al., 1970, 1973, 1978a,b, 1980, 1985; Rao et al., 1974; Paropkari et al., 1980), Arabian Sea (Borole et al., 1982; Shankar et al., 1987), and in the western equatorial Indian Ocean (Murty et al., 1983). However, most of them were restricted to a few trace metals, and covered only the shelf and slope but not the deepsea region. Hence, a detailed investigation was undertaken on the distribution of minor elements (Cu, Ni, Cr, Co, Pb and V) in the shelf and deep-sea regions so as to understand their origin and sources to the northern Arabian Sea sediments.

Surfacial sediment samples at 33 stations were collected using a Peterson grab during ORV Sagar Kanya's 29th cruise in the northern Arabian Sea (Fig. 1) between latitudes 15-20°N and longitudes 65-73.30°'E. For trace metal analysis, about 10 g of uncontaminated sediment was collected from the central portion of the grab sample with a plastic spatula and then transferred into a polyethylene bag. The samples were washed with distilled water to remove salts, air dried and preserved at room temperature. Grain-size analysis was carried out by a sieving method (Carver, 1971). Clay minerals (< 2 #m size fraction) were identified following the procedures outlined by Carrol (1970), and Brindley and Brown (1980). Further, they were quantified by the method of Biscaye (1964) using

0304-4203/94/$07.00 © 1994 Elsevier Science B.V. All fights reserved SSDI 0304-4203(94)00003-V

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an X-ray diffractometer (Phillips PW 1730/PW 1390) with Cu-K a radiation. An aliquot of the sample (1.0 g) was digested with hydrofluoric acid and perchloric acid mixture (Chester and Hughes, 1969). Elemental concentrations were measured using a Perkin-Elmer (model 272) Atomic Absorption spectrometer using air-acetylene (for Cu, Ni, Cr, Co and Pb) and N20-acetylene (for V) fuel mixtures. The accuracy was checked with replicate analysis using USGS reference

rock (AGV 1) sample and the coefficient of variation (%) was found to be for Cu, 2.4; for Ni, 1.9; for Cr, 6.0; for Co, 3.2; for Pb, 2.6; and for V, 45.

3. Results and discussion

The distribution patterns of sand, silt, clay ratios and texture (Table 1) in the study region indicate

217

D. Satyanarayana, Y. Venkata Ramana/Marine Chemistry 47 (1994) 215-226 Table 1 Textural and grain size parameters of sediments Station No.

Inner ~aelf 5 6 17 29 30 31 32 33

Depth (m)

Latitude (°N)

Longitude (°E)

Sand (%)

Silt (%)

Clay (%)

Mean size (~)

Texture

40 40 23 78 70 33 28 31

16.00 17.00 19.15 20.00 20.00 20.00 20.00 20.00

73.20 73.00 72.25 70.30 71.00 71.30 72.00 72.30

22.0 6.6 0.3 17.9 10.5 4.3 1.4 0.6 7.9

34.8 45.7 28.7 44.3 46.5 36.6 32.3 34.7 37.8

43.2 47.5 71.0 37.8 43.0 59.1 66.3 64.7 58.0

6.97 7.87 9.06 6.83 7.44 8.57 8.83 8.84 8.05

Sand/silt/clay Silty clay Silty clay Clayey silt Clayey silt Silty clay Silty clay Silty clay Silty clay

75 80 276 85 85 80 42 65 78 78 89 195 150 80

16.00 17.00 17.00 18.00 18.00 18.00 18.00 19.00 19.00 19.00 19.00 19.00 20.00 20.00

73.00 72.30 72.00 71.00 71.30 72.00 72.30 72.00 71.30 71.00 70.30 70.00 69.30 70.00

79.9 85.5 20.4 92.4 88.5 75.4 70.1 81.7 93.0 95.5 89.7 91.1 90.6 78.7 80.8

11.6 7.9 63.4 2.6 7.0 14.4 15.2 10.5 4.2 1.8 5.7 2.6 5.0 13.7 11.8

8.5 6.6 16.2 5.0 4.5 10.2 14.7 7.8 2.8 2.7 4.6 6.3 4.4 7.6 7.3

2.67 2.09 6.12 1.82 2.46 3.52 3.46 3.07 2.05 1.91 2.34 2.31 1.93 2.82 2.76

Sand Sand Sandy silt Sand Sand Sand Sand Sand Sand Sand Sand Sand Sand Sand Sand

2040 3200 3700 3450 3550 3400 3400 2770 3200 3100 1900

15.00 16.00 1'6.00 17.00 17.00 17.00 18.00 19.00 19.00 20.00 20.00

72.00 68.00 70.00 70.00 67.00 65.00 68.00 69.00 67.00 68.00 69.00

5.7 12.5 10.0 11.9 11.8 4.5 11.5 10.6 17.7 17.8 23.4 12.5

53.8 50.9 51.9 37.1 52.3 55.5 54.0 49.1 48.0 86.9 40.3 48.2

40.5 36.6 38.1 51.0 35.9 40.0 34.5 40.3 34.3 45.3 36.3 39.3

7.51 7.06 7.47 8.15 7.30 7.70 7.39 7.56 6.81 7.17 6.50 7.33

Clayey silt Clayey silt Clayey silt Silty clay Clayey silt Clayey silt Clayey silt Clayey silt Clayey silt Silty clay Sand/silt/clay Clayey silt

Average Outer shelf 4 7 8 13 14 15 16 18 19 20 21 22 27 28

Average Deep sea 1 2 3 9 10 11 12 23 24 25 26

Average

three distinct sedimentary environments, namely (1) the inner shelf, with silty clay, (2) the outer shelf, comprising sand, and (3) the deep sea, consisting of clayey silt. The distribution of ~b (mean size) also supports this view. Stewart et al. (1965) observed a band of sediments with median grain size commonly in the silt and clay range.

A high percentage of coarse-grained sediments in the outer shelf was attributed to low sedimentation rates and bottom currents which winnow away the finer material from the coast onto the slope (Nair, 1975; Hashimi and Nair, 1976). Based on the distribution and abundance of clay

218

D. Satyanarayana, Y, Venkata Ramana/Marine Chemistry 47 (1994) 2 l 5- 226

Table "~ Weighted peak-area percentage of clay minerals in sediments Station No.

MontmoriUonite

Illite

Kaolinite

Chlorite

Inner shelf 5 6 17 29 30 31 32 33

51.4 53.2 70.0 70.0 71.0 72.3 75.4 69.5

16.5 23.7 t8.0 19.2 18.2 18.1 13.2 16.1

23.1 13.9 5.7 4.3 5.8 5.0 5.8 10.2

9.0 9.2 6.3 6.5 5.0 4.6 5.6 4.2

Outer shelf 4 7 8 13 14 15 16 18 19 20 21 22 27 28

23.7 30.9 30.3 18.7 17.1 34.0 56.2 38.2 40.2 27.9 9.5 8.8 31.4 16.2

58.0 33.2 46.2 60.7 58.5 44.7 32.5 39.9 39.2 58.4 67.4 67.6 47.0 50.3

5,2 15.2 14.3 11.3 14.9 14.0 7.1 10.5 13.0 5.8 14.7 9.4 9.2 14.7

13.1 11.7 9.2 9.3 9.5 7.3 4.2 11.4 7.6 7.9 8.4 14.2 12.4 18.8

Deep sea 1 2 3 9 10 11 12 23 24 25 26

29.3 14.6 23.1 21.7 15.9 13.2 19.4 24.1 34.8 54.7 41.5

47.7 66.0 54.7 56.5 65.9 65.6 63.4 51.3 47.4 30.6 40.2

11.5 10.9 12.5 12.9 10.2 9.2 7.3 13.2 11.3 4.7 8.8

11.5 8.5 9.7 8.9 8.0 12.0 9.9 11.4 6.5 10.0 9.5

minerals (Table 2), the study area is divided into two regions, namely (1) the montmorillonite-rich inner shelf, and (2) the illite-rich deep sea and outer-shelf regions. Montmorillonite-rich clays in the inner shelf are the direct reflection of the onshore rocks (basalts) of this region. The weathering products are transported by the rivers Narmada and Tapti, which drain the Deccan Trap basalts (Venkatarathnam et al., 1981; Nair et al., 1982). These clays are dispersed along the continental margin by the prevailing surface

circulation. The origin of illite in the deep-sea region is due to the Indus river which drains the Himalayan and sub-Himalayan terrains (Venkatarathnam et al., 1981). The regional distributions of Cu, Cr, Co and V (Figs. 2, 4-6) show relative enrichment of the inner shelf compared to the outer-shelf and deep-sea sediments. Ni exhibits a relative enrichment (Fig. 3) in the inner shelf compared to the outer-shelf sediments. The decreasing trend in their concentrations towards the outer shelf (Table 3) reflects their predominant lithogenous origin. The lithogenous materials include clay minerals (montmorillonite and illite) ferromagnesian minerals (amphiboles, pyroxenes and garnets), and heavy minerals (feldspars). Further, fine-grained sediments in the inner shelf with a low carbonate content (<10%) are characterised by higher concentrations of these trace elements compared to the coarse-grained sediments of the outer shelf with a relatively higher (20-30%) carbonate content. Rao et al. (1974) observed a relative enrichment of Cu in the inner shelf when compared to the outer shelf and slope sediments, which they attributed to the texture and dilution with carbonate content. A similar enrichment of Ni and Co in the inner shelf when compared with the outer shelf and slope regions off the west coast of India was reported by Murty et al. (1970, 1973). On the other hand, the regional distribution of Pb (Fig. 7) showed slight enrichment in the outershelf and deep sea when compared to inner-shelf sediments. Lower concentrations of Pb in the inner-shelf sediments may be due to an insignificant detrital contribution from the major rivers Narmada and Tapti. This was also evident from the low concentration of Pb (0.02 #mol/g) as reported by Subramanian et al. (1985) for these river sediments. The average metal/A1 ratios of Cu, Ni, and V showed relatively high values in the inner-shelf sediments (1.75, 1.95, 2.31, and 2.73 × 10 3 , respectively) compared to the outer-shelf sediments (0.74, 1.79, 1.03, and 1.80 x 10-3, respectively), resembling their respective regional distribution patterns, thus lending support to their continental origin. The Pb/AI ratio was relatively higher in the outer shelf (4.09 x 10-3)

219

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and deep sea (2.27 x 10 -3) when compared to inner-shelf sediments (1.41 × 10-3). This may be due to its predominant atmospheric input to the outer-shelf and deep-sea sediments. Further, the ratios of all the elements were relatively higher (Cu=0.46, Ni=0.71, Cr=l.00, Co=0.19, Pb =0.23, and V = 1.4 x 10 -3) than those in surface rocks (Martin and Maybeck, 1979) suggesting that some fractions of them were

of non-lithogenous origin, i.e. adsorption on F e - M n oxides and authigenic minerals such as anatase. The average concentration of Cu in the innershelf and deep-sea sediments (Table 3) obtained in the present study broadly agrees with earlier reports on the western continental shelf and Arabian deep-sea sediments. Similarly, the average concentration of Ni compares well with

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V = - 0 . 8 0 ) , and positive correlations with clay (Cu = 0.84, Cr = 0.62. V = 0.57) suggesting their common association with fine.grained sediments. Significant positive correlations were observed among them, namely between Cu and Ni (0.76), Cr (0.89), V (0.72), between Ni and Cr (0.65), Co (0.68), and between V and Cr (0.60), Co (0.70), Pb (0.62). They also showed significant correlations with AI (Cu = 0.61, Cr = 0.54 and V = 0.69) and Ti (Cu = 0.86, Ni = 0.60, Cr = 0.90. Co = 0,84

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and V = 0.69) indicating their co-ccurrence with lithogenous fraction of the sediment. Significant positive correlations of these elements with F e (Cu = 0.76, Ni = 0.56, Cr = 0.68 and Pb = 0.57) and with Mg (Cu = 0.52, Ni = 0.60 and Cr = 0.78) indicate their occurrence in ferromagnesian minerals that make up the bulk of the heavy mineral fraction of the sediment (Siddiquie and Mallik, 1972; Kidwai et al., 1981). Cr exhibited a significant positive correlation with Fe and Mn

(0.74), and Pb with Fe and Mn (0.83) suggesting their association with F e - M n oxides. Though not significant, Co also exhibited a positive correlation with Fe (0.33) and Mn (0.38), suggesting its association with F e - M n oxides, believed to be its common carriers (Jenne, 1968; Loring, 1976). Significant positive correlations of V with Fe (0.65) and Ti lend support to its occurrence with iron oxides, magnetite and ilmenite. Occurrence o f Tibearing minerals, particularly ilmenite in the

D. Sat.i,anara.vana, Y. Penkata Ramana/Marine Chemistrl' 47 (1994) 215-226

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4. Condnsions

(1) Based on the texture and clay mineral distribution, the study area can be broadly divided

into three regions: inner shelf, outer shelf, and deep sea. (2) Except Pb, all minor elements show relatively higher concentrations in the inner shelf and deep sea when compared to outer-shelf sediments. However, Pb exhibited higher concentrations in the deep sea and outer shelf when compared to innershelf sediments. (3) Metal/Al ratios indicate the occurrence of

Cu

1.59 0.28 0.93 1.78 1.43 1.42 0.68 0.71 1.98 0.44 0.50

Sources

Arabiaa Sea Inner shelf Outer shelf Deep sea

Western equatorial Indian Ocean Western continental slope Western continental shelf Indus shelf Arabian deep sea Coastal Arabian Sea Indian river sediments World surficial rocks

0.89 2.86 1.53 1.82 0.94 1.33 0.63 0.83

1.92 0.75 1.87

Ni

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2.63 0.44 1. ! 9

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Table 3 Comparison of average concentrations of minor elements (pmol/g) of Arabian Sea sediments

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Present study Present study Present study

Reference

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trace metals in both the lithogenous and nonlithogenous fractions of sediment. This is also supported by the correlation coefficients of trace elements among themselves and with other textural and chemical parameters. (4) The origin of trace metals can be traced to the presence of clay minerals (montmorillonite, illite), heavy minerals (amphiboles, pyroxenes, garnets feldspars), authigenic (anatase) and Ti-bearing minerals (ilmenite). Further, they might also be

incorporated into the sediments by adsorption onto Fe and Mn hydrous oxides.

Acknowledgements

The authors are thankful to Dr. B.N. Desai, Director, National Institute of Oceanography, Goa for according permission to participate in the ORV Sagar Kanyacruise and collect sediment

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samples. One of us (YVR) is thankful to the Department of Ocean Development for the award of a fellowship.

References Biscaye, P.E., 1964. Distinction between chlorite and kaolinite in recent sediments by X-ray diffraction. Am. Mineral., 49: 803-831. Borole, D.V., Sarin, M.M. and Somayajulu, B.L.K., 1982. Corn-

position of Narmada and Tapti estuarine particles and adjacent Arabian Sea sediments. Indian J. Mar. Sci., 11: 51-62. Brindley, G.W. and Brown, G., 1980. Crystal structures of clay minerals and their X-ray identification. London Mineral. Soc. Monogr., 5, 495 pp. Carrol, D., 1970. Clay minerals. A guide to their X-ray identification. Geol. Soc. Am. Spec. Pap., 126, 80 pp. Carver, R.E., 1971. Sedimentary Petrology. Wiley, London, 653 pp. Chester, R. and Hughes, M.J., 1969. Scheme for spectrophotometric determination of Cu, Pb, Ni, V and Co in marine sediments. Trans. Inst. Miner. Met., 77:37-41 Hashimi, N.H. and Nair, R.R., 1976. Carbonate components in

226

D. Satyanarayana, Y. Venkata Ramana/Marine Chemistry 47 (1994) 215- 226

the coarse fraction of western continental shelf (northern part) of India. Indian J. Mar. Sci., 5: 51--57. Jenne, E.A., 1968. Controls of Mn, Fe, Co. Ni, Cu and Zn concentrations in soils and water: the significant role of hydrous Mn and Fe oxides. In: R.A. Baker (Editor), Trace lnorganics in Water. Am. Chem. Soc. Adv. Chem. Ser. N. 73: 337--388. Kidwai, R.M., Nair, R.R. and Hashimi, N.H., 1981. Heavy minerals in the sediments on the outer continental shelf between Vengurla and Mangalore on the west coast of India. J. Geol. Soc. India, 22: 32-38. Loring, D.H,, 1976. The distribution and partition of cobalt, nickel, chromium and vanadium in the sediments of the Saguenay fjord. Can. J. Earth Sci., 13: 1706-1718. Martin, J.M. and Meybeck, M., 1979. Elemental mass-balance of material carried by major world rivers. Mar. Chem., 7: 173 206. Murty, P.S.N., Rao, Ch.M. and Reddy, C.V.G., 1970. Distribution of nickel in the marine sediments off the west coast of India. Curt. Sci., 39: 30-32. Murty, P.S.N., Rao, Ch.M. and Reddy, C.V.G., 1973. Partition patterns of iron, manganese, nickel and cobalt in the sediments off west coast of India. Indian J. Mar. Sci., 2: 612. Murty, P.S.N., Paropkari, A.L., Rao, Ch.M. and Topgi, R.S., 1978a. Distribution of some elements in the sediments of Gulf of Kutch. Indian J. Mar. Sci., 7: 44-46. Murty, P.S.N., Rao, Ch.M., Paropkari, A.L. and Topgi, R.S., 1976. Distribution patterns of aluminum, titanium, manganese, copper and nickel in sediments of the northern half of the western continental shelf of India. Indian J. Mar. Sci., 7: 67-71. Murty, P.S.N., Rao, Ch.M., Paropkari, A.L. and Topgi, R.S., 1980. Distribution of AI, Mn, Ni, Co and Cu in the nonlithogenous fractions of sediments of the northern half of the western continental shelf of India. Indian J. Mar. Sci., 9: 5660. Murty, P.S.N., Cronan, D.S., Rao, Ch.M., Paropkari, A.L., Topgi, R.S., Gupta, M.V.S. and Colley, N., 1983. Geo-

chemistry of sediment cores of the western equatorial lndia~~ Ocean, Mahasagar Bull. Natl. Inst. Oceanogr., 16:9 -30. Murty, P.S.N. Paropkari, A.L. and Rao, Ch.M., 1985. (}c¢~ chemistry of Zn in the sediments of the western continental shelf and slope of India. Mahasagar Bull Natl. Inst. Oceanogr., 18: 187-197. Nair, R.R.. 1975. Nature and origin of small scale topographic prominences on the western continental shelf of India. Indian J. Mar. Sci., 4: 25- 29. Nair, R.R., Hashimi, N.H. and Purnachandra Rao, V., 1982. Distribution and dispersal of clay minerals on the western continental shelf of India. Mar. Geol., 50: M I - M 9 . Paropkari, A.L., Topgi, R.S., Rao, Ch.M. and Murty, P.S.N.. 1980. Distribution of Fe, Mn, Ni, Co, Cu and Zn in nonlithogenous fractions of sediments of Gulf of Kutch. Indian J. Mar. Sci., 9:54 55. Rao, Ch.M., Murty, P.S.N. and Reddy, C.V.G., 1974. Partition patterns of copper in the sediments of the western continental shelf of India. Indian J. Mar. Sci., 3: 12-15. Shankar, R., Subba Rao, K.V. and Kolla, V., 1987. Geochemistry of surface sediments from the Arabian Sea. Mar. Geol., 76: 253--279. Siddiquie, H.N. and Mallik, T.K., 1972. An analysis of the mineral distribution patterns in the recent shelf sediments off Mangalore, India. Mar. Geol., 12" 359-391. Siddiquie, H.N., Rajamanickam, G.V. and Almeida, F., 1979. Surficial mineral deposits of the continental shelf of India. Proc. Int. Sem. Offshore Mineral Resources, Orleans (France). BRGM Doc., 57: 232-258. Stewart, R.A., Pilkey, O.H. and Nelson, B.W., 1965. Sediments of the northern Arabian Sea. Mar. Geol., 3:411-427. Subramanian, V., Van't Dack, L. and Grieken, R., 1985. Chemical composition of river sediments from the Indian sub-continent. Mar. Geol., 48: 271--279. Venkatarathnam, K., Kostecki, J.A., Robinson, F. and Biscaye, P.E.. 1981. Distributions and origin of clay minerals and quartz in surface sediments of the Arabian Sea. J. Sediment. Petrol., 51: 563-569.