Stasis and extinction of Silurian (Llandovery–Wenlock) trilobite associations related to oceanic cyclicity

Mikulic, Donald G.; Kluessendorf, Joanne

doi:10.1017/s0022336000027797

Cited by 14 publications

(5 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…sagitta , suggesting a middle Sheinwoodian to early Homerian age. This assignment of the middle Racine to the early Homerian is broadly consistent with previous studies of the macrofauna (Berry & Boucot ; Watkins ; Mikulic & Kluessendorf , ).…”

Section: Chronostratigraphy and Correlationsupporting

confidence: 91%

Identification of the late Homerian Mulde Excursion at the base of the Salina Group (Michigan Basin, USA)

Sullivan¹,

McLaughlin

Emsbo

et al. 2016

LET

View full text Add to dashboard Cite

Constraining the age of strata is a fundamental source of uncertainty in the study of sedimentary rocks, particularly in restricted basins that generally lack index fossils. An illustrative example of this is the evaporite‐bearing Salina Group in the Michigan Basin. Our integrated study of facies, paleontology, and stable isotope geochemistry from the base of the Salina Group in Wisconsin addresses long‐standing chronostratigraphic uncertainty surrounding these units. Conodont samples from the basal boundary interval (Racine‐Waubakee formation contact) produced non‐diagnostic ‘disaster’ and ‘recovery’ faunas typical of both the Mulde (Homerian) and Lau (Ludfordian) events. Strontium isotope analysis (87Sr/86Sr) of these conodonts from five horizons just below the boundary yield values between 0.70844 and 0.70850 confirming a Homerian age. Multiple carbon isotope profiles through this interval confirm the presence of a 2.5–3‰ positive excursion. Cumulatively these data constrain the base of the Salina Group in Wisconsin to the Mulde Excursion interval (late Homerian). This integrated study provides a sound initial step towards a deeper understanding of the processes of Silurian evaporite formation in the Michigan Basin.

show abstract

Section: Chronostratigraphy and Correlationsupporting

confidence: 91%

Identification of the late Homerian Mulde Excursion at the base of the Salina Group (Michigan Basin, USA)

Sullivan¹,

McLaughlin

Emsbo

et al. 2016

LET

View full text Add to dashboard Cite

show abstract

“…Abundance of Burmeisteria in the Precordillera basin is highest in shallow-water depositional facies (Astini, 1991). These occurrences match previous observations on environmental preferences of homalonotids, from different ages and units, mostly from siliciclastic platform settings (Gill, 1948; Thomas, 1979; Chlupáč, 1981; Fortey and Owens, 1997; Mikulic and Kluessendorf, 1999; Sandford, 2005; Crônier and Van Viersen, 2007; Simões et al, 2009). In particular, these trilobites are most frequent in depths between the fair-weather and the storm wave-base levels, and such an ecological restriction hinders their use in biostratigraphy at regional or larger scales.…”

Section: Discussionsupporting

confidence: 89%

The homalonotid trilobiteBurmeisteriaSalter, 1865 in the Lower Devonian of Argentina: new data in the context of southwestern Gondwana

2020

View full text Add to dashboard Cite

The homalonotid trilobite Burmeisteria Salter, 1865 is revised from material from the Lower Devonian of central western Argentina (the Talacasto Formation in the Precordillera Basin). In contrast to other closely related Devonian marine basins from South America (mainly Bolivia, Brazil and Uruguay), the only species recognized in Argentina include Burmeisteria herschelii (Murchison, 1839) and B. notica (Clarke, 1913). New observations on the structure of the carapace indicate that structures sometimes interpreted as granules with taxonomic meaning are, in fact, taphonomic characters that represent the fillings of pore canals exposed by decortication. The antero-ventral process of the rostral plate may be a locking device during enrollment, which allowed long-term defensive behavior with a minimum of muscular energy. Burmeisteria is an upper Silurian to Middle Devonian endemic representative of southwestern Gondwanan (Malvinokaffric) basins. In the Argentine Precordillera Basin, this genus is virtually restricted to a sandy, Pragian, stratigraphic interval capped by a marker bed first reported by Keidel in 1921.

show abstract

“…The model has been used widely (e.g. Mikulic & Kluessendorf 1999;Kershaw 2000; for further references see Jeppsson 1998). Under this model, two long, stable secundo episodes were separated by a brief, highly unstable interval: the Mulde Event (Jeppsson 1993(Jeppsson , 1997b.…”

Section: Extinctions Oceanic Cycles and Sea-level Changesmentioning

confidence: 99%

“…In addition to the global identi®cation of Datum 2 in graptolite sequences, biological and physical e ects of the Mulde Event have now been identi®ed in shallower successions in Gotland (Calner 1999(Calner , 2002Calner & SaÈ ll 1999;Calner et al 2000;Calner & Jeppsson 2003), Britain , Bohemia (KrÏ izÏ 1992, p. 16;KrÏ izÏ et al 1993;, Estonia (Nestor 1997), Nevada (Berry 1998), and preliminarily in the central USA (Mikulic & Kluessendorf 1999;Calner et al 2001). Previously described local e ects can now thereby be placed into a broader context.…”

mentioning

confidence: 99%

The Silurian Mulde Event and a scenario for secundo–secundo events

Jeppsson¹,

Calner²

2002

Transactions of the Royal Society of Edinburgh: Earth Sciences

103

View full text Add to dashboard Cite

Graphic correlation using graptolites and conodonts provides a high-resolution timescale for correlating from coastal to deep oceanic sections and, thereby, also a detailed record of the sequence of changes during the Mulde Secundo-Secundo Event. That interval includes sedimentary facies otherwise unknown in older Wenlock to early Ludlow strata on Gotland. The identified sequence of changes includes a detailed record of, in order: two extinctions (Datum points 1 and 1·5); widespread deposition of carbon-rich sediments extensive enough to cause a δ13C increase of c. 4.8‰, the onset, maximum and end of a sea-level fall and rise of at least 16 m during 30 kyr; a third extinction (Datum 2); a disaster fauna; and a slow faunal recovery. Thus, a secondary result of the event was a weakened greenhouse effect triggering a glaciation: the Gannarve Glaciation (new term). The order of changes proves that regression did not cause the extinctions. Faunal and sea-level changes, as well as the sedimentary succession, fit well with predictions based on an oceanic model. Extinctions were primarily caused by a severe drop in primary planktonic productivity, causing starvation among planktonic larvae in non-coastal settings. The Grötlingbo Bentonite (new term), the thickest in the Wenlock of Gotland, was deposited across the basin shortly after Datum 2. Temporal resolution is high enough to permit some comparison with Quaternary glaciations.

show abstract

Stasis and extinction of Silurian (Llandovery–Wenlock) trilobite associations related to oceanic cyclicity

Cited by 14 publications

References 11 publications

Identification of the late Homerian Mulde Excursion at the base of the Salina Group (Michigan Basin, USA)

Identification of the late Homerian Mulde Excursion at the base of the Salina Group (Michigan Basin, USA)

The homalonotid trilobiteBurmeisteriaSalter, 1865 in the Lower Devonian of Argentina: new data in the context of southwestern Gondwana

The Silurian Mulde Event and a scenario for secundo–secundo events

Contact Info

Product

Resources

About