Stratigraphic subdivision of the Quaternary of Poland

ABSTRACTThe Post Quarry, within the lower part of the type section of the Upper Triassic Cooper Canyon Formation in southern Garza County, western Texas, contains a remarkably diverse vertebrate assemblage. The Post Quarry has produced: the small temnospondylRileymillerus cosgriffi; the metoposauridApachesaurus gregorii; possible dicynodonts and eucynodonts; a clevosaurid sphenodontian; non-archosauriform archosauromorphs (Trilophosaurus dornorum, simiosaurians, and possiblyMalerisaurus); the phytosaurLeptosuchus; several aetosaurs (Calyptosuchus wellesi,Typothorax coccinarum,Paratypothorax, andDesmatosuchus smalli); the poposauroidShuvosaurus inexpectatus(“Chatterjeea elegans”); the rauisuchidPostosuchus kirkpatricki; an early crocodylomorph; several dinosauromorphs (the lagerpetidDromomeron gregorii, the silesauridTechnosaurus smalli, a herrerasaurid, and an early neotheropod); and several enigmatic small diapsids. Revised lithostratigraphic correlations of the lower Cooper Canyon Formation with the Tecovas Formation, the occurrence ofLeptosuchus, and the overall composition of the assemblage indicate that the Post Quarry falls within the Adamanian biozone, and not the Revueltian biozone. Stratigraphic subdivision of the Adamanian biozone may be possible, and the Post Quarry may be correlative with the upper part of the Adamanian biozone in Arizona. The age of the Post Quarry assemblage is possibly late Lacian or earliest Alaunian (late early Norian or earliest middle Norian), between 220 and 215 Ma.

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Stratigraphy and eruptive history of the Late Devonian Mount Pleasant Caldera Complex, Canadian Appalachians

Geological Magazine ◽

10.1017/s0016756897006213 ◽

1997 ◽

Vol 134 (1) ◽

pp. 17-36 ◽

Cited By ~ 17

Author(s):

S. R. McCUTCHEON ◽

H. E. ANDERSON ◽

P. T. ROBINSON

Keyword(s):

Fractional Crystallization ◽

Basaltic Magma ◽

Late Devonian ◽

Crustal Material ◽

Basaltic Rocks ◽

Stratigraphic Subdivision ◽

Mount Pleasant ◽

History Of ◽

High Level ◽

Mafic Lavas

Stratigraphic, petrographic and geochemical evidence indicate that the volcano-sedimentary rocks of the Late Devonian Piskahegan Group, located in the northern Appalachians of southwestern New Brunswick, represent the eroded remnants of a large epicontinental caldera complex. This complex – the Mount Pleasant Caldera – is one of few recognizable pre-Cenozoic calderas and is divisible into Exocaldera, Intracaldera and Late Caldera-Fill sequences. The Intracaldera Sequence comprises four formations that crop out in a triangular-shaped area and includes: thick ash flow tuffs, thick sedimentary breccias that dip inward, and stocks of intermediate to felsic composition that intrude the volcanic pile or are localized along caldera-margin faults. The Exocaldera Sequence contains ash flow tuffs, mafic lavas, alluvial redbeds and porphyritic felsic lavas that comprise five formations. The Late Caldera-Fill Sequence contains rocks that are similar to those of the outflow facies and comprises two formations and two minor intrusive units. Geochemical and mineralogical data support the stratigraphic subdivision and indicate that the basaltic rocks are mantle-derived and have intraplate chemical affinities. The andesites were probably derived from basaltic magma by fractional crystallization and assimilation of crustal material. The various felsic units are related by episodes of fractional crystallization in a high-level, zoned magma chamber. Fractionation was repeatedly interrupted by eruption of material from the roof zone such that seven stages of caldera development have been identified. The genesis of the caldera is related to a period of lithospheric thinning that followed the Acadian Orogeny in the northern Appalachians.

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Mineralogical characteristic of quaternary sediments (sand fraction) from the southern extremity of the Chukchi plateau, Arctic ocean

Океанология ◽

10.31857/s0030-1574594617-640 ◽

2019 ◽

Vol 59 (4) ◽

pp. 617-640

Author(s):

O. N. Kolesnik ◽

A. N. Kolesnik ◽

E. G. Vologina ◽

A. A. Maryash

Keyword(s):

Arctic Ocean ◽

Fine Sand ◽

Quaternary Sediments ◽

Mineralogical Analysis ◽

Sand Fraction ◽

Accessory Minerals ◽

Stratigraphic Subdivision ◽

Mineralogical Characteristic ◽

Chukchi Plateau ◽

Southern Extremity

The data on mineralogical analysis of fine sand fractions in sediments accumulated in the southern part of the Chukchi Plateau during the Quaternary are presented. The associations and downcore distribution of the rock-forming and accessory minerals in relation to other characteristics are considered. The established climatically controlled mineralogical features, i. e. periodicity of warmings and coolings, can be used in solving a number of genetic problems, stratigraphic subdivision of sediments and paleoreconstructions.

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Rapid climate change during the last glacial–interglacial transition; implications for stratigraphic subdivision, correlation and dating

Global and Planetary Change ◽

10.1016/s0921-8181(01)00078-9 ◽

2001 ◽

Vol 30 (1-2) ◽

pp. 59-72 ◽

Cited By ~ 20

Author(s):

M.J.C Walker

Keyword(s):

Climate Change ◽

Last Glacial ◽

Rapid Climate Change ◽

Stratigraphic Subdivision ◽

The Last Glacial

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On the stratigraphic subdivision of rocks between the basis of the Devonian and the Cambrian

Zeitschrift der Deutschen Geologischen Gesellschaft ◽

10.1127/zdgg/111/1959/221 ◽

1959 ◽

Vol 111 (1) ◽

pp. 221-228

Author(s):

Hans-Rudolf. v. Gaertner

Keyword(s):

Stratigraphic Subdivision

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On stratigraphic subdivision of hominoid fossil localities of Yuanmou, Yunnan

Human Evolution ◽

10.1007/bf02437927 ◽

1994 ◽

Vol 9 (3) ◽

pp. 209-213

Author(s):

Zong Guanfu

Keyword(s):

Stratigraphic Subdivision

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Lateglacial environmental change in Scotland

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691017000184 ◽

2017 ◽

Vol 110 (1-2) ◽

pp. 173-198 ◽

Cited By ~ 5

Author(s):

Mike WALKER ◽

John LOWE

Keyword(s):

Environmental Change ◽

Ice Cores ◽

Future Research ◽

Spatial And Temporal Patterns ◽

Exposure Dating ◽

Time Period ◽

Stratigraphic Subdivision ◽

Event Stratigraphy ◽

Research Programmes ◽

History Of

ABSTRACTThis paper reviews the evidence for environmental change during the Lateglacial period (c.14.7–11.7 ka), perhaps the most intensively studied episode in the Quaternary history of Scotland. It considers first the stratigraphic subdivision and nomenclature of the Lateglacial, before proceeding to a discussion of the various lines of proxy evidence that have been used to reconstruct the spatial and temporal patterns of environmental change during this time period. These include pollen and plant macrofossil data; coleopteran and chironomid records; diatom data; stable isotope and geochemical records; and evidence for human activity. The paper then considers the principal methods that have been employed to date and correlate Lateglacial events: radiocarbon dating; surface exposure dating; varve chronology; and tephrochronology. This is followed by an examination of the constraints imposed on environmental reconstructions, an account of the ways in which the evidence can be employed in the development of an event stratigraphy for the Lateglacial in Scotland, and a proposal for a provisional Lateglacial type sequence (stratotype) at Whitrig Bog in SE Scotland. Emphasis is placed throughout on the potential linkages between the Scottish records and the isotopic signal in the Greenland ice cores, which forms the stratigraphic template for the N Atlantic region. The paper concludes with a discussion of the strategies and approaches that should underpin future research programmes on Lateglacial environmental change in Scotland.

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