Disaster opportunists Guembelitrinidae; index for environmental catastrophes

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doi: 10.1016/j.marmicro.2004.04.012
Author(s): Keller, Gerta; Pardo, Alfonso
Author Affiliation(s): Primary:
Princeton University, Department of Geological and Geophysical Sciences, Princeton, NJ, United States
Other:
Fundación San Valero, Spain
Volume Title: Marine Micropaleontology
Source: Marine Micropaleontology, 53(1-2), p.83-116. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0377-8398 CODEN: MAMIDH
Note: In English. Includes appendix. 111 refs.; illus., incl. strat. cols., 1 plate, 1 table, sketch map
Summary: Blooms of the disaster opportunist Guembelitria species are proxies for environmental catastrophes, whether impact or volcanism, leading to severe biotic stress crises that may range from temporary exclusion of ecological specialists and generalists to mass extinctions. During the late Maastrichtian and early Danian (zones P0 and Pla), Guembelitria blooms show global distributions, but with the largest blooms (40-80% Guembelitria) in low and middle latitudes and only minor blooms (10-20%) in high latitudes. Late Maastrichtian Guembelitria blooms are, so far, known from the Indian Ocean and eastern Tethys. The most intense Guembelitria blooms (>60% Guembelitria) occurred in shallow continental shelf areas, slope/shelf margins and volcanic provinces of the Indian Ocean. What these environments have in common is high nutrient influx (eutrophication) either from continental runoff, upwelling along continental margins or volcanic input. At times of biotic crises, Guembelitria blooms may have spread rapidly to the exclusion of most or all other species, much like today's red tides, but with near global distributions. A simple model can explain the ecological succession and recovery phases that follow major biotic perturbations caused by impacts or volcanism that lead to exclusion of specialist and most generalist species. Within such highly stressed environments, Guembelitria is the only genus to thrive, and without competition, rapidly reproduce and exponentially increase their populations. When nutrients are depleted, populations rapidly decrease, leading to ecologic niches for other generalists and ecosystem recovery. Small low-O2-tolerant heterohelicid populations mark this second stage, followed by small trochospiral and planispiral species. With further environmental recovery, increasing competition, niche development and restoration of a well-stratified water mass, oligotrophic conditions are restored, opening habitats for the highly specialized and diverse species and a return to normal diverse assemblages. This ecological succession is observed in association with mantle plume volcanism in the Indian Ocean and eastern Tethys during the late Maastrichtian, and in association with the K-T impact and volcanism during the early Tertiary. Abstract Copyright (2004) Elsevier, B.V.
Year of Publication: 2004
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Africa; Atlantic Ocean; Cenozoic; Cretaceous; DSDP Site 216; DSDP Site 525; DSDP Site 528; Danian; Deep Sea Drilling Project; Eastern U.S.; Europe; Eutrophication; Foraminifera; Guembelitria; IPOD; Impacts; Indian Ocean; Indian Ocean Islands; Invertebrata; K-T boundary; Leg 113; Leg 119; Leg 22; Leg 74; Lower Paleocene; Madagascar; Maestrichtian; Marine environment; Mass extinctions; Mesozoic; Microfossils; Models; North Africa; ODP Site 690; ODP Site 738; Ocean Drilling Program; Paleocene; Paleoecology; Paleoenvironment; Paleogene; Protista; Senonian; Shelf environment; Southeastern U.S.; Stratigraphic boundary; Tertiary; United States; Upper Cretaceous; Upper Maestrichtian; Volcanism
Coordinates: S290415 S290414 E0025908 E0025907
S283130 S283129 E0021927 E0021926
N012743 N012744 E0901229 E0901228
S624233 S624232 E0824715 E0824714
S650938 S650937 E0011218 E0011218
Record ID: 2005062104
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands