Following up on his recent magnum opus that considered universal sequence stratigraphy, Burgess
explores the depth of “what we really know” about the fundamental controls on
sequence stratigraphy in his most recent contribution. Wasting no words,
with nary a flaw in style or content, he lucidly and simply describes his
perspective on this question, and in doing so, illuminates gaps in
understanding. His unusually succinct style carefully avoids the jargon common
in sequence stratigraphy, so even beginners can grasp his points. [Ed. Note: We
appreciate Dr. Burgess’ brief abstract, shorter than even many physics
articles, which are notoriously curt. Even though it is a
review paper, it is the early favorite to win the Outstanding Paper Award.]
Friday, April 1, 2016
Wednesday, February 24, 2016
Highlights—Muddy Coastal Systems
Mud-dominated coastal systems play by their own rules. Many of
the generalizations derived from years of study of sandy shoreline systems
appear to not apply to shaley successions, or at least apply in unique ways. To
better understand spatial changes and proximal-to-distal facies relationships
of muddy systems, Harazim and McIlroy describe sedimentological, ichnological, and
geochemical characteristics of the Lower Ordovician (Tremadocian) Beach
Formation, Bell Island Group, Newfoundland. The results demonstrate that
ancient fine-grained coastal systems are incompletely incorporated into
sequence stratigraphic models owing to their atypical proximal-to-distal facies
relationships, unique physical sedimentologic properties, and burial
efficiency. The interpretations highlight the importance of 1) frequency
of sediment supply events, 2) direction of mud transport, 3) diagenetic
reactivity of minerals and bioavailable organic carbon, and (4) residence time
of mineral grains and organic matter close to the sediment–water interface on
facies architecture of this non-uniformitarian paleoenvironment, deposited
prior to the evolution of soils. Face
it, mud is complicated.
Mud-rich density-driven flows along an Early Ordovician storm-dominated shoreline: implications for shallow-marine facies models by Dario Harazim
and Duncan McIlroy
Wednesday, January 20, 2016
Highlights—The Poop on the Cretaceous–Paleogene Boundary, OR, Did the K–Pg Event Scare the Crap Out of Echinoids?
The Cretaceous–Paleogene
boundary (K–Pg) represents a major event in earth history that impacted both terrestrial
and marine realms. To explore the nature of sea-level and biologic change,
Esmeray-Senletet al. explore strata straddling the Cretaceous–Paleogene
boundary event in the Haymana Basin, Turkey, using planktonic foraminiferal
biostratigraphy, a comprehensive microfacies analysis, and a sequence
stratigraphy. The results illustrate a catastrophic and abrupt extinction
of planktonic foraminifera in the Haymana Basin at the boundary. Immediately
above the boundary is an enrichment of authigenic clay minerals and an
extraordinary increase in abundance of echinoid fecal pellets, interpreted to
represent low sedimentation rates; this signal may provide a criteria for
identifying this horizon regionally. Comparing the interpreted relative
sea-level curve of the Haymana Basin with sections in Europe, North Africa, and
New Jersey, suggests similar trends in sea-level change, and indicate that the
K–Pg boundary occurred during a global sea-level rise.
Planktonic foraminiferal biostratigraphy, microfacies analysis, sequence stratigraphy, and sea-level changes across theCretaceous–Paleogene Boundary in the Haymana Basin, Central Anatolia, Turkey by Selen Esmeray-Senlet, Sevinç Özkan-Altiner, Demir
Altiner, and Kenneth G. Miller
Monday, January 11, 2016
Highlights—Tilting the Table in the Book Cliffs
Many
sequence stratigraphic studies have emphasized the important role of eustatic
change on sequence architecture, led to large extent by studies in the Book
Cliffs region of Utah and Colorado. This paper by Madof et al.
tests the hypothesis that deposition within the late Cretaceous western
interior foreland basin was modulated by the interaction of eustatic change and
regional patterns of flexural subsidence—and suggest that it fails. The paper
describes new insights concerning relationships among deposition (shallow
marine, marginal marine, nonmarine facies), thickness trends, and geometrical
relationships. The data suggest syndepositional tilting markedly influenced patterns, and cast
doubt on the flexure-eustatic conceptual model for the origin of sequences in
this area. Instead, the authors explain the patterns of deposition within the
Book Cliffs in terms of an actively deforming basin, and propose that
stratigraphic architecture can be fully understood only in three dimensions.
Tectonically controlled nearshore deposition: Cozzette Sandstone, Book Cliffs, Colorado, U.S.A. by Andrew
S. Madof, Nicholas Christie-Blick, and Mark H. Anders
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