Precambrian perspectives
1
872 D. Submarine Geology and Geophysics OLR (1981)28 (!2) least 1.3 cm uplift/1000 yrs. USGS, Washington, D.C. 20560, USA. (hbf) 81:6567 Dunn, D.A., T.C. Moore Jr. and L.D. Keigwin Jr., 1981. Atlam~-typ~ ¢admm~ ~ ia the Late Miocene ~ , Nature, Lond., 291(58t2): 225-227. Stable C and O isotope ratios for the benthic foram Globocassidulina subglobosa and benthic/planktonic foram ratios were computed for Late Miocene samples from 2 DSDP Site 158 cores on the Cocos Ridge. Results show a negative correlation between carbonate content and benthic 0 isotopes similar to the Quaternary Atlantic record (but unlike the Pacific) which may reflect the flow of Atlantic-type water through the Miocene Panama Seaway. Grad- uate School of Oceanography, Univ. of Rhode Island, Kingston, R.I. 02881, USA. (hbf) g1:6[$ Funnell, B.M., 1981. ~ od[~ . J. geol. Soc., Lond, 138(2):177-181. Sea level change, evaporite deposition and possibly CO2 injection are found to independently drive autocorrelation of outer Earth processes. The sig- nificance of past variations in oceanic sedimentation and magnetic reversal/sea level changes is consid- ered. School of Environ. Sci., Univ. of East Anglia, Norwich NR4 7TJ, UK. (mcs) 81:6569 Goodwill, A.M., 1981. ~ pemlF~qlves. Science, 213(4503):55-61. A three-phase history, marked by progressive con- tinental stability, is suggested for the 4-billion year period preceding the appearance of macro-life forms. Changes in bulk earth heat production, crustal fractionation and cratonization, and an increase in atmospheric oxygen have caused the Earth to pass from an early, mobile microplate stage through an intracratonic, ensialic mobile belt phase to a large, rigid macroplate phase not unlike that of the present. Dept. of Geol., Univ. of Toronto, Toronto, MSS IA1 Canada. (hbf) Gossler, 1~ ¢mimm Beitr. A~8053 Graz, Austria. 81:6f70 Guo, Xudong, 198 82. (In Chinese, English summary.) $1:6571 81:6572 Gutsalo, L.K., 1981. Com~m~ ol the Wm~Ocean's sallalty aud ariel eoacmtnaloa ia the Earth's a t ~ dm~ the i~ncmm4¢. Dokl. Akad. Nauk SSSR, 257(6):1457-1460. (In Russian.) 81.'6573 Harland, W.B., 1981. Chxmm~gy of Earth's glacial md tcet~i¢ record. J. geol. Sot., Lond.. 138(2): 197 -203. Whether glaciation has been relatively continuous. cyclic, or irregularly episodic is uncertain, A case is made for the lattermost based on its 'methodological soundness': assuming no periodicity allows 'cycles to be discovered' if, indeed, they did/do exist. Dept. of Earth Sci., Univ. of Cambridge, Downing St.. Cambridge CB2 3EQ, UK. (izs) 81:6574 Heller, P.L., K.W. Flessa (comment), K.G. Miller and R.K. Olsson (reply), 1981. Forum. Late oataeme trmFm~ of the ~ Aamac coastal plain. Geology, geol. Soc. Am.. 9(7):290- 292. 81:6575 Lcggett, J.K., W.S. McKerrow, L.R.M. Cocks and R.B. Rickards, 1981. Pecladld~ fm the Early Pala~m~le m~na¢ realm, J. geol. Soc., Lond., 138(2):167-176. Evidence from the British Isles on faunal diversity, oxygen levels and sea level fluctuations is examined for secular variations and durations. Early Palaeo- zoic perturbations seem to lack the 'regular perio- dicity' of those of the Mesozoic and Cenozoic, possibly related to the greater tendency for anoxia in Early Palaeozoic seas. Dept. of Geol.. Imperial College, London SW7 2BP, UK. (izs) 81:6576 Mackenzie, F.T. and J.D. Pigott, 1981. Tectonic eoam~s d pkaaerua~ ~ reek eyeXag. J. geoL Soc., Lond., 138(2):183-196. Garrels and Mackenzie 0969, 1971) proposed two 350-Ma cycles of erosion and ~tion, separated by a pc~od of reduced ~mnntary transfer cor- responding to the Devonian,Carboniferous time of major continental collision. Cyclicity of the Phanero- zoic global sea level curve correlates strongly with C and S sedimentary modes, supporting the hypothesis A dominant role for tectonics is indicated in the cycling of sedimentary rocks. Dept. of Geol. Sci.. Northwestern Univ., Evanston, IlL 60201. USA. (sir)
Transcript of Precambrian perspectives
872 D. Submarine Geology and Geophysics OLR (1981)28 (!2)
least 1.3 cm uplift/1000 yrs. USGS, Washington, D.C. 20560, USA. (hbf)
81:6567 Dunn, D.A., T.C. Moore Jr. and L.D. Keigwin Jr.,
1981. Atlam~-typ~ ¢admm~ ~ ia the Late Miocene ~ , Nature, Lond., 291(58t2): 225-227.
Stable C and O isotope ratios for the benthic foram Globocassidulina subglobosa and benthic/planktonic foram ratios were computed for Late Miocene samples from 2 DSDP Site 158 cores on the Cocos Ridge. Results show a negative correlation between carbonate content and benthic 0 isotopes similar to the Quaternary Atlantic record (but unlike the Pacific) which may reflect the flow of Atlantic-type water through the Miocene Panama Seaway. Grad- uate School of Oceanography, Univ. of Rhode Island, Kingston, R.I. 02881, USA. (hbf)
g1 :6 [$ Funnell, B.M., 1981. ~ od[ ~ .
J. geol. Soc., Lond, 138(2):177-181.
Sea level change, evaporite deposition and possibly CO 2 injection are found to independently drive autocorrelation of outer Earth processes. The sig- nificance of past variations in oceanic sedimentation and magnetic reversal/sea level changes is consid- ered. School of Environ. Sci., Univ. of East Anglia, Norwich NR4 7TJ, UK. (mcs)
81:6569 Goodwill, A.M., 1981. ~ pemlF~qlves.
Science, 213(4503):55-61.
A three-phase history, marked by progressive con- tinental stability, is suggested for the 4-billion year period preceding the appearance of macro-life forms. Changes in bulk earth heat production, crustal fractionation and cratonization, and an increase in atmospheric oxygen have caused the Earth to pass from an early, mobile microplate stage through an intracratonic, ensialic mobile belt phase to a large, rigid macroplate phase not unlike that of the present. Dept. of Geol., Univ. of Toronto, Toronto, MSS IA1 Canada. (hbf)
Gossler, 1~ ¢mimm Beitr. A~8053 Graz, Austria.
81:6f70
Guo, Xudong, 198
82. (In Chinese, English summary.)
$1:6571
81:6572 Gutsalo, L.K., 1981. Com~m~ ol the Wm~Ocean's
sallalty aud ariel eoacmtnaloa ia the Earth's a t ~ d m ~ the i~ncmm4¢. Dokl. Akad. Nauk SSSR, 257(6):1457-1460. (In Russian.)
81.'6573 Harland, W.B., 1981. Chxmm~gy of Earth's glacial
md tcet~i¢ record. J. geol. Sot., Lond.. 138(2): 197 -203.
Whether glaciation has been relatively continuous. cyclic, or irregularly episodic is uncertain, A case is made for the lattermost based on its 'methodological soundness': assuming no periodicity allows 'cycles to be discovered' if, indeed, they did/do exist. Dept. of Earth Sci., Univ. of Cambridge, Downing St.. Cambridge CB2 3EQ, UK. (izs)
81:6574 Heller, P.L., K.W. Flessa (comment), K.G. Miller
and R.K. Olsson (reply), 1981. Forum. Late oataeme t r m F m ~ of the ~ Aamac coastal plain. Geology, geol. Soc. Am.. 9(7):290- 292.
81:6575 Lcggett, J.K., W.S. McKerrow, L.R.M. Cocks and
R.B. Rickards, 1981. Pecladld~ fm the Early Pala~m~le m~na¢ realm, J. geol. Soc., Lond., 138(2):167-176.
Evidence from the British Isles on faunal diversity, oxygen levels and sea level fluctuations is examined for secular variations and durations. Early Palaeo- zoic perturbations seem to lack the 'regular perio- dicity' of those of the Mesozoic and Cenozoic, possibly related to the greater tendency for anoxia in Early Palaeozoic seas. Dept. of Geol.. Imperial College, London SW7 2BP, UK. (izs)
81:6576 Mackenzie, F.T. and J.D. Pigott, 1981. Tectonic
eoam~s d pkaaerua~ ~ reek eyeXag. J. geoL Soc., Lond., 138(2):183-196.
Garrels and Mackenzie 0969, 1971) proposed two 350-Ma cycles of erosion and ~tion, separated by a pc~od of reduced ~ m n n t a r y transfer cor- responding to the Devonian,Carboniferous time of major continental collision. Cyclicity of the Phanero- zoic global sea level curve correlates strongly with C and S sedimentary modes, supporting the hypothesis A dominant role for tectonics is indicated in the cycling of sedimentary rocks. Dept. of Geol. Sci.. Northwestern Univ., Evanston, IlL 60201. USA. (sir)
