Biostratigraphic expression of Pleistocene sequence boundaries, Gulf of Mexico

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doi: 10.2307/3515169
Author(s): Martin, Ronald E.; Neff, Eric D.; Johnson, Glenn W.; Krantz, David E.
Author Affiliation(s): Primary:
University of Delaware, Department of Geology, Newark, DE, United States
University of Rhode Island, United States
McLaren-Hart Environmental Management, United States
Volume Title: Palaios
Source: Palaios, 8(2), p.155-171. Publisher: Society of Economic Paleontologists and Mineralogists, Tulsa, OK, United States. ISSN: 0883-1351
Note: In English. 86 refs.; illus., incl. 1 table
Summary: The sedimentary record of Ocean Drilling Program's Core 625B (northeast Gulf of Mexico) contains significant unconformities that represent a record of sea-level change during the Pleistocene. The core may thus serve as a standard for timing of sea-level changes of the western Gulf, the stratigraphic record of which has been distorted by salt and shale tectonics. Utilizing primarily relative abundances of the warm-water Globorotalia menardii complex and cool (temperate)-water G. inflata, we have subdivided the pre-zone W Pleistocene of Core 625B into 17 subzones, resulting in an average duration of approximately 100,000 years per unit. The subzones are recognizable not only in other cores [Eureka Core E67-135 (northeast Gulf of Mexico), DSDP Core 502B (Colombia Basin, Caribbean Sea) and V16-205 (tropical Atlantic)], but also in cuttings from the industrial well Garden Banks Block 412 Unocal No.1 (western Gulf of Mexico), Based on graphic correlation, subzonal boundaries are largely co-eval between sites, and can provide high-resolution biostratigraphic subdivision of the Pleistocene of industrial wells on an operational (day-to-day) basis. Moreover, the subzonation reveals changes in sediment accumulation rate that reflect sequence boundaries at the Zone Y/X (∼0.09 Ma), W/V1 (∼0.2 Ma), V2/V3 (∼0.4 Ma), U/T (∼0.525-0.620 Ma), T3/T4 (∼0.7-0.9 Ma), T4/S1 (∼1.0 Ma), S2/S3-S3/R1 (∼1.2 Ma), R2/R3-R3/Q1 (∼1.4-1.5 Ma), and Q2/P-P/Pliocene (∼1.8-1.9 Ma) boundaries, and a regionally condensed section in Subzone R1 (∼1.3 Ma). Our age assignments for ecozone-based sequence boundaries are in substantial agreement with those of previous workers. Also, the subzonation delineates anomalous paleotops that are reworked, erosionally truncated at sequence boundaries, or delta-depressed as a result of localized sediment influx.
Year of Publication: 1993
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Algae; Atlantic Ocean; Biostratigraphy; Biozones; Caribbean Sea; Cenozoic; Colombian Basin; Correlation; DSDP Site 502; Deep Sea Drilling Project; Foraminifera; Garden Banks; Graphic methods; Gulf of Mexico; IPOD; Invertebrata; Leg 100; Leg 68; Lower Pleistocene; Marine sedimentation; Microfossils; Nannofossils; North Atlantic; ODP Site 625; Ocean Drilling Program; Paleomagnetism; Paleorelief; Plantae; Pleistocene; Protista; Quaternary; Sea-level changes; Sedimentation; Sedimentation rates; Stratigraphic boundary; Thallophytes; Upper Pleistocene
Coordinates: N112925 N112925 W0792247 W0792247
N284954 N284954 W0870936 W0870936
Record ID: 1997012869
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by SEPM (Society for Sedimentary Geology), Tulsa, OK, United States