UTRECHT MICROPALEONTOLOGICAL BUllETINS

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may interfinger. Evidently biogenic sedimentation had already started while at other places the Arenazzolo was still being deposited. Sedimentation of the Trubi was locally interrupted by renewed supply and deposition of coarser terrigenous material. Such alternations are normal features in marginal areas displaying rapid horizontal changes in environmental conditions, which may become reflected in vertical sections. Such rapid variations in depositional types may be expected to become strongly reduced to scale, or to be absent, in the more remote, i.e. central parts of the basin, such as in the successions along the sourthern coast of Sicily. The wash residues of the four samples collected from the newly described transitional interval at Eraclea Minoa clearly reflect the different lithologies. The Trubi intercalation contains the smallest number of mica flakes. The underlying and overlying samples contain large amounts of mica, gypsum and pyritic grains in addition to other clastic debris. The topmost sample of this transitional interval again contains less mica. The conservation of the foraminiferal tests is good in the Trubi intercalation and transitional marls (sample 4). Brown ferruginous coatings are frequent on the benthonic tests in the other two samples. The planktonic foraminifera in the latter two samples are much better preserved than the benthonic foraminifera. Only 20 benthonic species have been recorded in a total of 100 counted specimens in the Trubi intercalation (fig. 6), whereas 42 to 47 species were encountered in the other three samples. The Trubi intercalation (sample 2) is 4gminated by five benthonic species; in descending order of abundance these are: Gyroidina soldanii, Dentalina filiformis, Epistominella exigua, Oridorsalis umbonatus and Gyroidina umbonata. All five species are frE'quent elements in the overlying Trubi sediments (cf. Brolsma, 1975b, figs. 7 and 13). In the other three samples Ammonia beccarii, Bolivina species, Bulimina species, Elphidium species and epiphytes are the most conspicuous elements. The number of benthonic specimens per 200 counted planktonic specimens is 10 and 15 in samples 1 and 3, but less than 1 in samples 2 and 4. Smaller quantities of planktonic forms in samples 1 and 3 are held responsible for the relatively high number of benthonics per 200 counted planktonic individuals. In samples 2 and 4 planktonic foraminifera are very abundant and no benthonics were encountered in the total of 200 counted planktonic specimens. The occasional presence of Globorotalia margaritae (primi tiva-type) in samples 1 and 4 is worth mentioning.
2 3 4 2 3 1 5 2 6 1 8 10 1 1 9 2 4 1 4 5 1 4 4 3 4 2 6 4 7 3 4 1 1 3 3 1 6 5 3 1 6 4 2 2 4 1 3 16 1 45 100 ~ Ammonia beccarii Bolivina antiqua Bolivina dilatata Bolivina plicatella var. mera Bolivina reticulata Bolivina spp. Bulimina aculeata Bulimina spp. Cassidulina laevigata Cibicides pseudoungerianus Cibicides refulgens Cibicides tenellus Dentalina filiformis Elphidium spp. Epistominella exigua Fissurina spp./Lagena spp. Gyroidina orbicularis /parva Gyroidina soldanii Gyroidina umbonata Hanzawaia boueana Melonis barleeanus Oridorsalis umbonatus Rosalina globularis Stilostomella adolphina Globocassidulina subglobosa Astrononion italicum Cassidulina laevigata var. carinata Cibicides bradyi Nuttallides rugosus var. convexus Cibicides lobatulus Miscellaneous Indeterminable Total number of counted species Total number of counted specimens Number of benthonics/200 planktonics Lithostratigraphic column of exposure 3 at Eraclea Minoa with the distribution of the benthonic species.
Page 1 and 2: UTRECHT MICROPALEONTOLOGICAL BUllET
Page 3 and 4: QUANTITATIVE FORAMINIFERAL ANALYSIS
Page 5 and 6: The foraminifera. . . . . . . . . .
Page 7 and 8: Benthonic and planktonic foraminife
Page 9 and 10: and considerable lowering of the er
Page 11 and 12: topmost Messinian evaporites, chara
Page 13 and 14: literature together with Pachysphae
Page 16 and 17: Data and conclusions from the earli
Page 18 and 19: 2 3 Ammonia beccarii Bolivina dente
Page 20 and 21: LITHOLOGY The new exposure to be de
Page 24: CONCLUSIONS The mediocre preservati
Page 27 and 28: 107 107G B.C 107A 106 1394 64 1393
Page 29 and 30: Fig. 9 Laterally displaced loadcast
Page 31 and 32: Orbulina, which in turn seem to dep
Page 33 and 34: 0 10 20cm. L--L--J ~II\\ :::0 if.-
Page 35 and 36: whether its assumed intermediate st
Page 37 and 38: cate that larger burrowing organism
Page 39 and 40: The foraminiferal faunas from the T
Page 41 and 42: 42 43 44 45 sa~ 3 4 4 Astrononion i
Page 43 and 44: the accumulation of silica-rich sed
Page 45 and 46: 1 1 i z 1 1 11 3 1 i ~ . 2 •• 7
Page 47 and 48: ently favoured clayey substrates bu
Page 49 and 50: The next higher part of the section
Page 51 and 52: Cibicides pseudoungerianus appears
Page 53 and 54: In the next higher interval the alt
Page 55 and 56: high. It remains equally possible t
Page 57 and 58: I 106 55 52 j 8 Ij I " ~ ~ ! I ll11
Page 59 and 60: 107A 107B 107C 107D 107E 107F 107G
Page 61 and 62: of the faunas remains practically t
Page 63 and 64: 5 -- 4 3 2 7 - - - - - - - - - - -
Page 65 and 66: ;.Monica Say(32) Todos Santos 8ay (
Page 67 and 68: 1000 m, the latter corresponding to
Page 69 and 70: In this respect it is interesting t
Page 71 and 72: for this interval at the three loca
Page 73 and 74:
near-absence and bloom. The level o
Page 75 and 76:
Fig. 30 Punta Piccola section, show
Page 77 and 78:
Chlorite/montmorillonite and albite
Page 79:
most of them are of the order of 15
Page 83 and 84:
The change in colour from cream to
Page 85 and 86:
The foraminiferal faunas from the M
Page 87 and 88:
, " ~ " , , . ~ . ~
Page 89 and 90:
posite- reactions with higher a-val
Page 91 and 92:
------ Cibicides lobatu(us -- Hanza
Page 93 and 94:
Bulimina inflata, Hopkinsina bononi
Page 95 and 96:
Parker, 1954). In the Andaman Sea t
Page 97 and 98:
athymetric distribution is shown in
Page 99 and 100:
in the manganese-rich interbeds (B
Page 101 and 102:
50 1~N 47 46 45 43 4 M 42 L 41 4 39
Page 103 and 104:
Emiliani (1974) analyzed core mater
Page 105 and 106:
20323, was deposited at the transit
Page 107 and 108:
it is realized that the latter two
Page 109 and 110:
FREQUENCY D ISTR I BUTION OF SOME S
Page 111 and 112:
BENTHONIC FORAMINIFERAL ASSOCIATION
Page 113 and 114:
IK < .o~
Page 115 and 116:
ed by the increase of epiphytes and
Page 117 and 118:
G. puncticulata, recorded from Aren
Page 119 and 120:
our sample 93 suddenly shows a B/P
Page 121 and 122:
loss may be due to the folding. The
Page 123 and 124:
shallowing tendency. This quiet sed
Page 125 and 126:
One of the major aims of this inves
Page 127 and 128:
anean evidently had a nutrient supp
Page 129 and 130:
A taxonomical treatment of all figu
Page 131 and 132:
Remarks: Globigerina pseudobesa (Sa
Page 133 and 134:
Remarks: Colalongo and Sartoni (196
Page 135 and 136:
30. Earland, A. (1934). Foraminifer
Page 137 and 138:
Anderson, G. ]. (1963). Distributio
Page 139 and 140:
Hsii, K. J., Cita, M. B. and Ryan,
Page 141 and 142:
Wright, R. (1977). Neogene paleobat
Page 144:
Figs. 1a-b Figs. 2a-b Figs.3a-b Fig
Page 148:
Figs. 1a-c Figs. 2a-c Figs. 3a-c Fi
Page 152:
Fig. 1 Fig. 2 Figs.3a-b Fig. 4 Fig.
Page 156:
Morphological gradation from Globor
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UTRECHT MICROPALEONTOLOGICAL BUllETINS

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