Del objetivo específico N° 2

1. This is the first detailed study of its kind to analyse, interpret and present deep water agglutinated foraminiferal data from the central Arctic Ocean. The study highlights the importance and role of deep water agglutinated foraminifera in the Arctic Ocean. The deep water agglutinated foraminifera show a strong correlation with the interglacial/glacial cycles in many of the cores, from both the Eurasian and Amerasian Basin during the Pliocene-Pleistocene. This highlights their importance

in stratigraphie studies. Their ecological characteristics are used to reconstruct and provide palaeoenvironmental interpretations for the habitat in which they lived. Palaeoceanographic interpretations provided by other microfossil groups are strengthened by the deep water agglutinated foraminifera which furthers the palaeoceanographic information of the region. Deep water agglutinated foraminifera contribute to finding the solution to palaeoproductivity problems of the Arctic Ocean. The Arctic Ocean region has a major influence on global climate and ocean systems. Therefore, it is hoped that further investigation into the behaviour, taxonomy and application of the deep water agglutinated foraminifera will enable future detailed interpretation into the complex mechanisms and controlling factors which drive the central Arctic Ocean today and in the past.

2. Future research using DWAF in the central Arctic Ocean would need to be carried out in conjunction with calcareous benthic foraminifera producing a more complete palaeoenvironmental and palaeoceanographic model for the region. Further widespread coring and the collection all physical and chemical parameters, (sample weights, salinity, water temperature, sediment chemistry) would be required. Particle size analyses would enhance interpretation of the data, along with more detailed age models for all cores.

Taxonomy

Order: FORAME^JIFERIDA Eichwald 1830 Suborder: TEXTULARHNA Delage & Herouard, 1896

Superfamily Astrorhizacea Brady, 1881a Family Rhabdamminidae Brady, 1884 Subfamily Rhabdammininae Brady, 1884

Genus Rhabdammina Brady, 1879

Rhabdammina antarctica S aide va, 1975 (PLI, fig. 1)

1975, Rhabdammina antarctica, Saidova, pi. 2, fig. 1.

Material: Core PS2177-5, 32 specimens; Core PS2200-5, 6 specimens; Core PI- 92-AR 39 (106-2000), 2 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Straight tube which is slightly inflated at the centre. Quartz grains of varying diameter, but generally of smaller dimensions at one end of the tube. Distance between the larger grains varies, grains are tightly packed and one layer thick on the wall. Sharp edges of the grains protrude. External surface of test is rough. Internal surface is smooth. Pelitic material between the grains is light brown. Wall thickness is > 0.5 mm.

Remarks: Saidova (1975) noted that this species is found in the upper bathyal zone of the Antarctic, Ross Sea, Bellinghausen Sea and Southern subtropics. This is the first report of this species in the Arctic, therefore, it has a bipolar distribution.

Dimensions: Smallest: Length = 0.26 mm. Width = 0.14 mm. Largest: Length = 0.64 mm. Width = 0.24 mm.

Rhabdammina discreta Brady, 1881a (PL 1, fig. 2)

1881, Rhabdammina discreta, Brady. Original designation, not illustrated. 1884, Rhabdammina discreta, Brady, pi. 22, figs. 8-10.

Material: Core PS2177-5, 10 specimens; Core PS2200-5, 26 specimens; Core PS2212-3, 10 specimens; Core PS2185-6, 1 specimen; PI-92-AR 27 (125-2000), 2 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: The test is cylindrical and open at both ends, consisting of a straight or nearly straight tube. This is segmented with annular constrictions, but with no

internal partitions. Wall is several grains thick and finely cemented. Aperture is at the open end of the tube. All specimens present are broken.

Dimensions: Smallest: Length = 0.18 mm, Width = 0.52 mm. Largest: Length = 1.75 mm, Width = 0.59 mm.

Rhabdammina sp. 1 (PI. 1, fig. 3)

Plesiotype: Core PS2177-5, Sample 690 cm. Box 25, la.

Material: Core PS2177-5, 6 specimens; Core PS2200-5, 65 specimens; Core PS2212-3, 4 specimens; Core PS2185-6, 7 specimens; Core PI-92-AR P39 (106- 2000), 7 specimens; Core PI-92-AR 39 (63-106), 1 specimen.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Straight tube. It is even and the tube has an equal diameter along its length. The fine grained inter-granular cement is light brown. Grains are of similar dimensions along the length of the tube and one layer thick. Smooth internal surface. Wall thickness is 0.01 mm, tube diameter 0.5 mm.

Remarks: This species differs from Hyperammina by the absence of a proloculus.

Rhabdammina antarctica appears to be very similar, however, the uniform grain size and absence of inflated region in this species distinguishes it from R. antarctica. This species also occurs in Core PI-92-AR 39 from the Northwind Ridge, Canada Basin. Evidence from Cronin et al. (1994) suggests that the high abundance in Core PS2200-5 may be explained by the outflowing of water masses northwest of the Fram Strait near the boundary between the outflowing Intermediate Arctic (200-800 m) and Deep Arctic water masses. This would increase the amount of suspended food particles available and thus the productivity of the foraminifera.

Dimensions: Smallest: Length = 0.70 mm. Width = 0.52 mm. Largest: Length = 1.22 mm. Width = 0.70 mm.

Family Psammosphaeridae Haeckel, 1894 Subfamily Psammosphaerinae Haeckel, 1894

Genus Psammosphaera Schulze, 1875

Psammosphaera fusca Schulze, 1875, emend Heron-Allen & Farland, 1913 (PI. 1, fig. 4)

1875, Psammosphaera fusca Schulze, p. 113, pi. 2, fig. 8a-f.

Material: Core PS2177-5, 64 specimens; Core PS2200-5, 210 specimens; Core PS2212-3, 5 specimens; Core PS2185-6, 47 specimens; Core PI-92-AR 39, (106- 2000), 59 specimens; PI-92-AR 30 (125-2000), 4 specimens; PI-93-AR 21 (125- 2000), 2 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Unilocular test which is spherical to sub-spherical. Comprised of sand grains cemented to an inner organic lining. The tests and grains vary in size. The wall is thicker than the grains and the inside of the wall is smooth. Aperture is a rounded large opening.

Dimensions: Smallest: Length = 0.4 mm, Width = 0.4 mm. Largest = 0.56 mm, Width = 0.54 mm.

Superfamily Ammodiscacea Reuss, 1862 Family Ammodiscidae Reuss, 1862 Subfamily Ammovertellininae Saidova, 1981

Genus Glomospira Rzehak, 1885

Glomospira gordialis (Jones & Parker, 1860) (PI. 1, figs. 5, 6)

1860, Trochammina squamata Jones and Parker var. gordialis Jones and Parker,: no type figure given.

1990, Glomospira gordialis (Jones and Parker), Berggren & Kaminski pi. 1, fig. 1.

Material: Core PS2177-5, 36 specimens; Core PS2200-5, 3 specimens; Core PS2212-3, 3 specimens; Core PS2185-6, 1 specimens; Core PI-92-AR 39 (106- 2000), 37 specimens; Core PI-92-AR 39 (63-106), 126 specimens; Core PI-92-AR 27 (125-2000), 2 specimens. Core PI-92-AR 27 (63-125), 7 specimens; Core PI- 92-AR 30 (125-2000), 1 specimen; Core PI-92-AR 30 (63-125), 22 specimens; Core PI-93 AR 21 (125-2000), 1 specimen; Core PI-93 AR 21 (63-125), 2 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Test comprised of proloculus, undivided tubular second chamber which is streptospirally coiled about a common plane. This occurs with five or six whorls of open coiling, not enrolled and umbilicus is usually visible and depressed. Final part of tube may be irregular. Wall is finely imperforate, finely agglutinated with a smooth finish. Aperture is at open end of tube.

Dimensions: Smallest: Length = 0.08 mm. Width = 0.08 mm. Largest: Length = 0.14 mm. Width = 0.2 mm.

Glomospira charoides (Jones & Parker) (PI. l,fig. 7, 8)

1860, Trochammina squamata var charoides (Jones & Parker): no type figure given.

1990, Glomospira charoides (Jones and Parker), Berggren & Kaminski pl. 1, fig.

2.

Material: Core PS2177-5, 23 specimens; Core PS2200-5, 3 specimens; Core PS2212-3, 1 specimen; Core PI-92-AR 39 (106-2000), 37 specimens; Core PI-92- AR 39 (63-106), 474 specimens; PI-92-AR 27 (125-2000), 1 specimen; PI-92-AR 27 (63-125), 9 specimens; PI-92-AR 30 (63-125), 25 specimens; PI-93-AR 21 (63-125), 13 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Test free, proloculus followed by trochospirally enrolled, undivided tubular second chamber. This is coiled around a vertical axis. Test is comprised of approximately three coils. Finely agglutinated wall, smooth surface. Aperture at end of the tube.

Dimensions: Smallest: Length = 0.1 mm. Width = 0.06 mm. Largest: Length = 0.1 mm. Width = 0.12 mm.

Superfamily Cyclolinacea Loeblich & Tappan 1964 Family Cyclamminidae Marie, 1941

Subfamily Cyclammininae Marie, 1941 Genus Cyclammina Brady, 1879

Cyclammina Brady, 1881b (PI. 2, figs. 1,2,)

1881, Cyclammina pusilla Brady, p. 53.

1884, Cyclammina pusilla Brady, p. 354, pi. 37, fig. 20, 21.

Material: Core PS2177-5, 697 specimens; Core PS2200-5, 3906 specimens; Core PS2185-6, 1209 specimens; Core PI-92-AR 39 (106-2000), 574 specimens; Core PI-92-AR 39 (63-106), 1 specimen; PI-92-AR 27 (125-2000), 602 specimens; PI- 92-AR 30 (125-2000), 781 specimens; PI-93-AR 21 (125-2000), 345 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Biconvex test. Depressed at the umbilicus with an acute slightly lobulate periphery. Three complete whorls, the last of which has ten to fifteen segments. Alveolar structure is poorly developed. Sutures are depressed and vary from straight to sigmoidal. The sutures are not always visible in the specimens and the grains are moderately coarse, densely packed and tightly cemented. Grains consist of quartz and black mafic fragments. Cement is light brown in colour. Walls thin. Inner surface shows a simple structure labyrinthic structure (small pseudo pores). Little variation in grain size between the specimens.

Remarks: The specimens are smaller and more coarsely agglutinated than the syntype specimens of C. pusilla [from CHALLENGER Station 323 in the South Atlantic] preserved in the Brady Collection, Natural History Museum, London. As

a result the sutures are not as clearly defined. The species is apparently common in the polar regions, as Earl and (1934) reported it as "abundant in deep-water clays" from the Weddell Sea.

Dimensions: Smallest: Length = 0.29 mm, Width = 0.26 mm. Largest: Length = 0.66 mm. Width = 0.64 mm.

Cyclammina sp. 1 (PI. 1, figs. 3,4)

Plesiotype: Core PS2185-6 (KAL), Morris Jesup Rise, Arctic Ocean. Sample 671

cm. Box 51, la.

Material: Core PS2200-5, 20 specimens; Core PS2185-6, 15 specimens; Core PI- 92-AR 39 (106-2000), 11 specimens; Core PI-92-AR 39 (63-106), 2 specimens; Core PI-92-AR 30 (63-125), 2 specimens; Core PI-93-AR 21 (125-2000), 30 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Small test. Semi-rounded periphery. Finely agglutinated, with shiny appearance. Slightly depressed at the umbilicus. Three complete whorls which are shown in broken specimens, with eight/nine chambers in final whorl. Sutures are distinct and curve slightly in some specimens. Cement dark brown in colour. Walls thin, no variation in grain size between specimens. In side view, final chamber is rounded to pointed, with the aperture, a semi-circular slit, resting on and in the centre of the final chamber.

Remarks: Cyclammina pusilla is different to Cyclammina sp. 1 being smaller in its size, having fewer chambers and the test wall has finer grain size.

Dimensions: Smallest: Length = 0.25 mm. Width = 0.3 mm. Largest: Length = 0.6 mm. Width = 0.5 mm.

Cyclammina sp. 2 (PI. 2, figs. 5, 6)

Plesiotype: Core PS2185-6 (KAL), Morris Jesup Rise, Arctic Ocean. Sample 751cm, Box 26, la.

Material: Core PS2185-6, 2 specimens; PI-92-AR 39 (106-2000), 2 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Small test. Semi-rounded periphery. Finely agglutinated, with shiny appearance. Umbilicus not depressed (convex). Three complete whorls which are shown in broken specimens, with seven/eight chambers in final whorl. Sutures are straight. Cement light brown in colour. Walls thin, no variation in grain size between specimens. In side view, final chamber is rounded and broadens form the

its base to top from the final chamber. The aperture is a semi-circular slit, resting to one side on the final chamber.

Remarks: This species differs from Cyclammina sp. 1 by its rounded final chamber in side view, the position of the aperture to one side of the final chamber is different to that found in Cyclammina sp. 1 and Cyclammina sp. 2 has fewer chambers (seven/eight). It is also less abundant in all of the cores examined in comparison with Cyclammina sp. 1.

Dimensions: Smallest: lost specimens. Largest: Length = 0.5 mm. Width = 0.3 mm.

Cyclammina sp. 3 (PI. 2, figs. 7, 8, 9)

Plesiotype: PS 2185-6 (KAL), Morris Jesup Rise, Arctic Ocean. Sample 751cm, Box 26, 3b.

Material: Core PS2185-6, 7 specimens, PI-93-AR 21 (125-2000), 1 specimen.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Small test. Sub-rounded periphery. Finely agglutinated, with shiny appearance. Umbilicus is depressed. Three complete whorls which are shown in broken specimens, with eight chambers in final whorl. Large final chamber. Sutures vary between curved and straight. The suture between the prolocolus and second chamber is curved, the remainder are straight, until the suture between the penultimate and final chamber, which is curved. Cement light brown in colour. Walls thin, no variation in grain size between specimens. In side view, final chamber is rounded, long and broadens from its base to top from the final chamber. The aperture is a semi-circular slit, resting on and in the centre of the final chamber.

Remarks: This species differs from Cyclammina sp. 1, by its rounded proloculus in side view, nature of the aperture and having fewer chambers. It differs from

Cyclammina sp. 2 in a number of ways. The final chamber is more bulbous and longer from the base of the chamber compared with Cyclammina sp. 3. It has depressed umbilicus, where it is more convex in Cyclammina sp. 2 and the central position of the aperture resting on the final chamber is different to the side position of the aperture in Cyclammina sp. 2. It, like Cyclammina sp. 2, is less abundant in all of the cores examined in comparison with Cyclammina sp. 1.

Dimensions: Smallest: Length = 0.2 mm. Width = 0.2 mm. Largest: Length = 0.3 mm. Width = 0.3 mm.

Subfamily Alveolphragmiinae Saidova, 1981 Genus Alveolophragmium Shchedrina, 1936

Alveolophragmium polarensis O'Neill, 1981 (Pl. 3, figs. 1,2, 3,4, 5, 6)

1981, O'Neill, Alveolophragmium polarensis pl. 2, figs. 15, 16.

Material: Core PS2200-5, 744 specimens; Core PS2212-3, 95 specimens; Core PS2185-6, 120 specimens; Core PI-92-AR 39 (106-2000), 130 specimens; Core PI-92-AR 39 (63-106), 2 specimens; PI-92-AR 27 (125-2000), 10 specimens; PI- 92-AR 30, (125-2000), 55 specimens; PI-93-AR 21 (125-2000), 33 specimens. Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Test free, multilocular. Planispiral, involute. Periphery rounded. Organic cement. Two whorls, with nine/ten chambers in final whorl. Outer whorl encompassed inner whorl. Umbilical region is smooth and rounded when viewed internally. Large proloculus and broad final chamber. Depressed sutures are seen in some specimens and are darker than chambers. Some specimens are coarsely agglutinated, which restricts viewing the sutures. Solid outer surface to test wall, with holes (alveoles) in the wall itself, internal section of wall is solid. The interior is complex, with the chamber walls often filled with holes. Many specimens are often coated with pyrite, giving a dark or black appearance. Aperture is equatorial, just above the base of the final chamber face, and a simple slit in the early chambers, later a linear series of irregular to rounded openings. Aperture is sometimes obscured by large sedimentary particles.

Remarks: In appearance this species is very similar to C ribrostom oides subglobosus forma subglobosus. However, Alveolophragmium polarensis differs from C. subglobosus forma su b g lo b o su s in the wall structure, with

Alveolophragmium polarensis possessing holes in the wall and in the internal make up of the test. Many of the specimens examined are often less coarse than those illustrated by O'Neill (1981). It is observed that the smaller, possibly juvenile, specimens of this species have the same form of coiling, however, the aperture is more commonly a simple equatorial slit, whereas the larger specimens have simple slits and some have a series of irregular openings which make up the aperture.

Dimensions: Smallest: Length = 0.42 mm. Width = 0.35 mm. Aperture face view = 0.45 mm. Largest: Length = 1.05 mm. Width =1.01 mm. Aperture face view = 0.52 mm.

Superfamily Haplophragmiacea Eimer & Fickert ( 1899) Family Ammosphaeroidinidae Cushman, 1927 Family Ammosphaeroidinidae Cushman, 1927 Subfamily Ammosphaeroidininae Cushman, 1927

Genus Cystammina Neumayr, 1889

Cystammina pauciloculata (Brady, 1879) (Pl. 3, fig. 7)

1879, Brady, Trochammina pauciloculata p.58, pl. 5, figs, 13-14. 1960, Barker, Cystammina pauciloculata (Brady), pl. 41, figs. 1-2.

Material: Core PI-92-AR P39, 63-106|Lim 4 specimens, 106-2000|xm, 55 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Test free, four globular-rounded chambers visible. Depressed sutures. Wall is finely arenaceous with a polished appearance. Aperture is not easily visible under the microscope.

Remarks : SEM work needs to be carried out so that this species can be described in more detail.

Dimensions: Smallest: Length = 0.1 mm. Width = 0.1 mm. Largest: Length = 0.2 mm. Width = 0.18 mm.

Subfamily Recurvoidinae Alekseychik-Mitskevich, 1973 Genus Recurvoides^^.v\^nà., 1934

Recurvoides contortus Barland, 1934 (PI. 3, fig. 8; PI. 4, fig. 1,2) 1934, Recurvoides contortus Barland, p. 91, pi. 10, figs. 7-9.

1969, Cribrostomoides subglobosus (Cushman). Vilks, p. 45, pi. 1, fig. 18a-b.

Plesiotype: PS 2200-5 (KAL), Sample 188 cm. Box 38, Ic.

Material: Core PS2200-5, 9 specimens; PI-92-AR 39 (106-2000), 1 specimen; PI-92-AR 27 (125-2000), 24 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

D escription: Test free, quite large. Coarsely agglutinated, robust test. Streptospiral, coiling plane of each whorl approximately 90° apart. Sutures difficult to discern, but possible to see some separations in some specimens. These separate the test into five chambers, when looked at spiral view. Aperture semi-circular slit, with slight lip, which rests on the final chamber.

Remarks: The smaller specimens, possibly juvenile often have the appearance of

Trochammina, contrary to this, larger specimens may be mistaken for juvenile

Cribrostomoides. The problem of identifying chambers and sutures on the test, may be related to the coarse nature of the sediment. This may be of ecological significance for the species, suggesting that it enjoys a relatively coarse sedimentary environment, viz. Cyclammina pusilla and Alveolophragmium polarensis. The species is similar in appearance to R ecurvoides brideauxi

Schroder-Adams & McNeil (1994), however, the test is not as robust.

Dimensions: Smallest: Length = 0.4 mm, Width = 0.3 mm, Aperture face view = 0.4 mm. Largest: Length = 0.8 mm. Width = 0.5 mm. Aperture face view = 0.6 mm.

Suborder Trochamminina Bronnimann & Whittaker, 1988

Superfamily Trochamminacea Schwager, 1877, (emended Bronnimann, Zaninetti, & Whittaker, 1983, emended Bronnimann & Whittaker, 1990)

Family Trochamminidae Schwager, 1877, (emended Bronnimann, Zaninetti, & Whittaker, 1983)

Subfamily Trochammininae Schwager, 1877, emended Bronnimann & Whittaker, 1988

Genus Trochammina Parker & Jones, 1859 emended Bronnimann & Whittaker, 1988

Trochammina lomonosovensis Evans and Kaminski (in press) (PI. 4, fig. 3,4, 5, 6)

Holotype: Sample PS2177-5, 545 cm from a site on the Lomonosov Ridge situated at 88° 2.1'N, 134° 36.7'E, water depth of 1400 m, sediment recovered 6.94 m. Deposited in the Micropalaeontology collections of the NHM, London.

Diagnosis: Trochospiral, rounded and compact test. Four to four and a half chambers in final whorl on umbilical side, one interiomarginal aperture.

Derivation of name: Lomonosov Ridge, central Arctic Ocean, where it was found in abundance and where its characteristic aperture was observed.

Material: Core PS2177-5, 102 specimens; Core PS2200-5, 43 specimens. Core PS2185-6, 51 specimens; Core PI-92-AR 39 (106-2000), 18 specimens; PI-92-AR 27 (125-2000), 81 specimens; PI-92-AR 27 (63-125), 1 specimen; PI-92-AR 30 (125-2000), 25 specimens, PI-92-AR 30 (63-125), 2 specimens, PI-93-AR 21 (125-2000), 117 specimens; PI-93-AR 21 (63-125), 3 specimens.

Horizon: Pliocene and Pleistocene. See Appendix I.

Description: Test free, rounded and compact in outline, concavo-convex in shape, not watch-glass like. Wall coarsely agglutinated, giving the specimen a "blocky" appearance, imperforate and single layered. Wall has inner and outer organic sheets. Spiral side, low convex, coiling not easily visible. Proloculus is small and difficult to see because the surface of the test is obstructed with sediment or is smoothed, therefore, total number of chambers in the test not given. On umbilical side four to four and a half chambers are visible in the final whorl, the ultimate chamber is the largest and embraces the second and third chambers. Trochospiral coiling, compressed to rounded periphery. Chambers are subrounded. One aperture present, simple semi-circular opening, interiomarginal, resting on first/second chambers in the final whorl.

Remarks: Bronnimann & Whittaker (1988) indicated that the presence of single interiomarginal aperture distinguishes the Trochamminiae from the other five sub­ families of the Trochamminidae. Trochammina subglobigeriniformis Mikhalevich (1972) has a single interiomarginal aperture, however, the chambers increase rapidly in size, the spiral side of the test is flat, the periphery is broadly rounded, and even though its single aperture rests on the first chamber in the final whorl, it has a rim, which is absent in T . lomonosovensis. The genus Trochammina is distinguished from the genus Deuterammina by the presence of its single aperture. The umbilical region in Deuterammina is very open, the umbilical region has a star shaped aperture with a secondary preserved aperture at the umbilical end of the sutures (John E. Whittaker, personal communication). The genus

Trochammina differs from the genus Paratrochammina as the aperture lies at the base of the septum, therefore is closed toward the axial cavity and does not communicate directly with it (Bronnimann, 1979). However, in the description of