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A taxonomic revision of the unilocular Foraminifera
OLR (1987)34(12)
D. SubmarineGeologyand Geophysics
Ratios of dimorphic (microspheric/megalospheric) forms of Foraminifera are affected by temperature and hence are useful in paleoclimatic studies. In some cases, however, it is not possible to distinguish between the dimorphic forms and, therefore, mean proloculus size is useful. The mean proloculus size of Cavarotalia annectens was measured in 14 surface sediment samples from the near-shore region along the west coast of India (Bombay to Kannyakumari). The results show that mean proloculus size varies from 0.045 to 0.103 ram, and is inversely proportional to temperature and salinity variations. It is proposed, therefore, that mean proloculns size of Foraminifera can be used as an additional tool in paleoclimatic studies. Natl. Inst. of Oceanogr., Dona Paula, Goa 403 004, India. 87:6909 Oggioni, Elisabetta and Liliana Zandini, 1987. Response of benthic Foraminifera to stagnant episodes. A quantitative study of Core BAN 81-23, eastern Mediterranean. Mar. Geol., 75(14):241-261.
Changes in benthic foraminiferal faunas found in a core from the Ares Crater (western Mediterranean Ridge), which included seven sapropel and two tephra layers ranging in age from 5000 to 250,000 yrBP, are described and compared with changes across sapropels $6 through $3 in cores from the nearby Poseidon Plateau (Schilling, 1986). The study shows that a marked reduction in faunal density accompanied the cyclically repeated episodes of stagnation. A consistent sparse faunule of shallowwater epiphytic rotaliforms, probably transported by floating algae and Bolivina spp. and buliminids capable of tolerating very low oxygen levels, was found within the sapropels. Unlike the other layers, the top of sapropel $6 originated under glacial conditions and was preceded by peak abundances of faunal density. Dept. of Earth Sei., Univ. of Milan, Via Manglagalli 34, 20133 Milan, Italy. (hbf) 87:6910 Parisi, Elisabetta, 1987. Carbon and oxygen isotope comlmsition of G/ob~r/ao/des tuber in two deep-sea cores from the Levantine Basin (eastern Mediterrsnean). Mar. Geol., 75(1-4):201-219.
Carbon and oxygen isotope analyses were carried out on 114 samples of G. tuber from two deep-sea cores from the outer slopes of the Mediterranean Ridge. These cores contain the sedimentary history of the eastern Mediterranean in the last 300,000 yr and include sapropelitic layers Ss to S~0. Climatic fluctuations recorded by the isotopic signal correlate well with previous studies; most sapropelitic intervals correspond to warm climatic conditions. Only S6
1055
and partially Ss reflect glacial conditions, indicating an alternative model for the deposition of organicrich layers. The magnitude of fluctuations in oxygen isotope composition (about 7 ppt) is unusually wide for the eastern Mediterranean, and the record is generally shifted toward negative values for approximately 1 ppt, probably due to the Nile discharge. Oxygen and carbon curves are in phase showing the large influence of organic productivity on carbon isotope composition. Dept. of Earth Sei., Univ. of Milan, Via Mangiagalli 34, 20133, Milan, Italy. 87:6911 Patterson, R.T. and R.H. Richardson, 1987. A taxonomic revision of the ~ Forsminffera. J.foram. Res~ 17(3):212-226. Dept. of Earth and Space Sei., Univ. of Calif., Los Angeles, CA 90O24, USA. 87:6912 Por, F.D., 1986. Crustacean ~ of the Late Middle Miocene Middle Eastern landbHdge. Crustacean Issues, 4:69-84.
The low diversity crustacean fauna of the Levantine Basin reflects the influence of several dramatic changes in the region, including the establishment of the Middle Eastern landbridge (dividing the circumtropical Tethys Ocean), a subsequent period of drying, the 'Messinian Salinity Crisis' during which the basin contained only hypersaline lakes and species richness was greatly diminished, the influx of oceanic waters through Gibraltar, a series of Pleistocene cold periods, and cyclical wet and dry periods affecting the surrounding arid lands. The fauna of the Red and Mediterranean seas are compared and the impact of the Suez Canal is examined. Dept. of Zool., Hebrew Univ., Jerusalem, Israel. (gsb) 87:6913 Stabell, Bjerg, 1987. Changes in diatom floras in Late Qummmry wesm'u and southeastern N e ~ i a n marine and f n ~ h ~ ~ m ~ Response to basin isolation from the sea. Nova Hedwigia, 44(3-4):305-326. Dept. of Geol., Univ. of Oslo, P.O. Box 1047, Blindern, N-0316 Oslo 3, Norway. 87:6914 Van Harten, Dick, 1987. Oslrscedes and the Early Holoeene anoxk event in the eastern M e ~ e r ra~an-.-evidanee and ~ Mar. Geol~
75(I-4):263-269. Several species of deep-water ostracodes still common in the western Mediterranean became extinct in the eastern Mediterranean Basin at the onset of early
D. SubmarineGeologyand Geophysics
Ratios of dimorphic (microspheric/megalospheric) forms of Foraminifera are affected by temperature and hence are useful in paleoclimatic studies. In some cases, however, it is not possible to distinguish between the dimorphic forms and, therefore, mean proloculus size is useful. The mean proloculus size of Cavarotalia annectens was measured in 14 surface sediment samples from the near-shore region along the west coast of India (Bombay to Kannyakumari). The results show that mean proloculus size varies from 0.045 to 0.103 ram, and is inversely proportional to temperature and salinity variations. It is proposed, therefore, that mean proloculns size of Foraminifera can be used as an additional tool in paleoclimatic studies. Natl. Inst. of Oceanogr., Dona Paula, Goa 403 004, India. 87:6909 Oggioni, Elisabetta and Liliana Zandini, 1987. Response of benthic Foraminifera to stagnant episodes. A quantitative study of Core BAN 81-23, eastern Mediterranean. Mar. Geol., 75(14):241-261.
Changes in benthic foraminiferal faunas found in a core from the Ares Crater (western Mediterranean Ridge), which included seven sapropel and two tephra layers ranging in age from 5000 to 250,000 yrBP, are described and compared with changes across sapropels $6 through $3 in cores from the nearby Poseidon Plateau (Schilling, 1986). The study shows that a marked reduction in faunal density accompanied the cyclically repeated episodes of stagnation. A consistent sparse faunule of shallowwater epiphytic rotaliforms, probably transported by floating algae and Bolivina spp. and buliminids capable of tolerating very low oxygen levels, was found within the sapropels. Unlike the other layers, the top of sapropel $6 originated under glacial conditions and was preceded by peak abundances of faunal density. Dept. of Earth Sei., Univ. of Milan, Via Manglagalli 34, 20133 Milan, Italy. (hbf) 87:6910 Parisi, Elisabetta, 1987. Carbon and oxygen isotope comlmsition of G/ob~r/ao/des tuber in two deep-sea cores from the Levantine Basin (eastern Mediterrsnean). Mar. Geol., 75(1-4):201-219.
Carbon and oxygen isotope analyses were carried out on 114 samples of G. tuber from two deep-sea cores from the outer slopes of the Mediterranean Ridge. These cores contain the sedimentary history of the eastern Mediterranean in the last 300,000 yr and include sapropelitic layers Ss to S~0. Climatic fluctuations recorded by the isotopic signal correlate well with previous studies; most sapropelitic intervals correspond to warm climatic conditions. Only S6
1055
and partially Ss reflect glacial conditions, indicating an alternative model for the deposition of organicrich layers. The magnitude of fluctuations in oxygen isotope composition (about 7 ppt) is unusually wide for the eastern Mediterranean, and the record is generally shifted toward negative values for approximately 1 ppt, probably due to the Nile discharge. Oxygen and carbon curves are in phase showing the large influence of organic productivity on carbon isotope composition. Dept. of Earth Sei., Univ. of Milan, Via Mangiagalli 34, 20133, Milan, Italy. 87:6911 Patterson, R.T. and R.H. Richardson, 1987. A taxonomic revision of the ~ Forsminffera. J.foram. Res~ 17(3):212-226. Dept. of Earth and Space Sei., Univ. of Calif., Los Angeles, CA 90O24, USA. 87:6912 Por, F.D., 1986. Crustacean ~ of the Late Middle Miocene Middle Eastern landbHdge. Crustacean Issues, 4:69-84.
The low diversity crustacean fauna of the Levantine Basin reflects the influence of several dramatic changes in the region, including the establishment of the Middle Eastern landbridge (dividing the circumtropical Tethys Ocean), a subsequent period of drying, the 'Messinian Salinity Crisis' during which the basin contained only hypersaline lakes and species richness was greatly diminished, the influx of oceanic waters through Gibraltar, a series of Pleistocene cold periods, and cyclical wet and dry periods affecting the surrounding arid lands. The fauna of the Red and Mediterranean seas are compared and the impact of the Suez Canal is examined. Dept. of Zool., Hebrew Univ., Jerusalem, Israel. (gsb) 87:6913 Stabell, Bjerg, 1987. Changes in diatom floras in Late Qummmry wesm'u and southeastern N e ~ i a n marine and f n ~ h ~ ~ m ~ Response to basin isolation from the sea. Nova Hedwigia, 44(3-4):305-326. Dept. of Geol., Univ. of Oslo, P.O. Box 1047, Blindern, N-0316 Oslo 3, Norway. 87:6914 Van Harten, Dick, 1987. Oslrscedes and the Early Holoeene anoxk event in the eastern M e ~ e r ra~an-.-evidanee and ~ Mar. Geol~
75(I-4):263-269. Several species of deep-water ostracodes still common in the western Mediterranean became extinct in the eastern Mediterranean Basin at the onset of early