M-sequence reversals recorded in DSDP sediment cores from the western Mid-Pacific Mountains and Magellan Rise

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doi: 10.1130/0016-7606(1989)101<1306:MSRRID>2.3.CO;2
Author(s): Tarduno, John A.; Sliter, William V.; Bralower, Timothy J.; McWilliams, Michael; Premoli-Silva, Isabella; Ogg, James G.
Author Affiliation(s): Primary:
Stanford Univ., Dep. Geophys., Stanford, CA, United States
U. S. Geol. Surv., United States
Fla. Int. Univ., United States
Univ. Milano, Italy
Purdue Univ., United States
Volume Title: Geological Society of America Bulletin
Source: Geological Society of America Bulletin, 101(10), p.1306-1316. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0016-7606 CODEN: BUGMAF
Note: In English. 46 refs.; illus. incl. charts, sketch maps
Summary: New paleomagnetic and paleontologic data from Pacific DSDP Sites 463 and 167 define the magnetic reversals that predate the Cretaceous Normal Polarity Superchron (K-N). Data from Mid-Pacific Mountain Site 463 provide the first definition of polarity chron M0 in the Pacific deep-sea sedimentary record. Foraminiferal biostratigraphy suggests that polarity chron M0 is contained entirely within the lower Aptian Hedbergella similisZone, in agreement with foraminiferal data from the Italian Southern Alps and Atlantic Ocean. Nannofossil assemblages also suggest an early Aptian age for polarity chron M0, contrary to results from the Italian Umbrian Apennines and Southern Alps, which place polarity chron M0 on the Barremian-Aptian boundary. Biostratigraphic dating discrepancies caused by the time-transgressive, preservational, or provincial nature of paleontological species might be reconciled by the use of magnetostratigraphy, specifically polarity chron M0 which lies close to the Barremian-Aptian boundary.At Magellan Rise Site 167, five reversed polarity zones are recorded in Hauterivian to Aptian sediments. Correlation with M-anomalies is complicated by synsedimentary and postsedimentary sliding about 25 m.y. after basement formation, producing gaps in, and duplications of, the stratigraphic sequence. The magnitude and timing of such sliding must be addressed when evaluating the stratigraphy of these oceanic-rise environments.
Year of Publication: 1989
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
Key Words: 03 Geochronology; 12 Stratigraphy, Historical Geology and Paleoecology; Algae; Aptian; Barremian; Biostratigraphy; Carbonate rocks; Cores; Correlation; Cretaceous; DSDP Site 167; DSDP Site 463; Deep Sea Drilling Project; Demagnetization; Foraminifera; Geochronology; Hauterivian; Hedbergella similis; IPOD; Invertebrata; Leg 17; Leg 62; Limestone; Lower Cretaceous; Magellan Rise; Magnetic declination; Magnetic inclination; Magnetostratigraphy; Marine sediments; Mesozoic; Microfossils; Mid-Pacific Mountains; Nannofossils; North Pacific; Pacific Ocean; Paleomagnetism; Planktonic taxa; Plantae; Protista; Range; Reversals; Sedimentary rocks; Sediments; Thallophytes
Coordinates: N212101 N212101 E1744004 E1744004
N070406 N070406 W1764930 W1764930
Record ID: 1989065514
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