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The Pennsylvanian stratigraphic section of the Manzanita Mountains (central New Mexico, USA) is restudied at Cedro Peak. This Pennsylvanian succession is divided into the Sandia Formation, Gray Mesa Fm, Atrasado Fm, and lower part of Bursum Fm. The sampled limestones of the Gray Mesa and Atrasado formations yielded three age-distinctive fossil assemblages: they are of (a) latest Atokan/early Desmoinesian, (b) late early Desmoinesian, and (c) middle Virgilian. The following new taxa of foraminifers are proposed: Endoteboidea n. superfam.; Spireitlinidae n. fam.; Millerellinae n. subfam.; Pseudonovella marshalli n. sp.; Pseudonovella ohioicus nom. nov.; Pseudoacutella n. gen.; Pseudoacutella hoarei nom. nov.; Plectofusulina manzanensis n. sp. Translated or emended names are: Staffelloidea, Ozawainelloidea, Ozawainellidae, and Profusulinellidae. 相似文献
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215.
Summary A local intraplatform basin developed in the Gartnerkofel-Zielkofel area of the Carnic Alps (southern Carinthia, Austria)
during the Middle Triassic (Ladinian). This basin was filled with a transgressive basinal sequence composed of the Uggowitz
Formation and overlying Buchenstein Formation. At the northwestern slope of the Gartnerkofel, the platform carbonates of the
Schlern Dolomite interfinger with the Buchenstein Formation, causing the formation of two depositional sequences.
The Uggowitz Formation consists of the Uggowitz Breccia and the Kühweg Member. Sediments of the Uggowitz Breccia were formed
by different types of gravity induced processes. The Kühweg Member is a thin sequence of silt-and fine-grained sandstones
which were deposited in a slope to basin margin environment by turbidity currents. The overlying Buchenstein Formation consists
of hemipelagic to pelagic limestones of Fassanian age with intercalated pyroclastic rocks (Pietra verde). Nodular limestones
were deposited under slow rates of accumulation during a relative sea-level highstand. The uppermost Buchenstein Formation
is composed of hemipelagic limestone beds with intercalated graded calcarenites and breccias of platform-derived debris, showing
characteristics features of a fore-reef slope of the prograding Schlern Dolomite.
Uggowitz Formation and basal Buchenstein Formation are interpreted as a transgressive systems tract, nodular limestones from
the middle part of the Buchenstein Formation mark an early highstand systems tract, forereef slope sediments of the upper
Buchenstein Formation formed during the beginning regression of a late highstand systems tract, the basal part of the overlying
Schlern Dolomite probably reflects a lowstand systems tract.
The intercalated bedded limestone facies within the Schlern Dolomite is characterized by large, platform derived blocks, slump
structures, breccia beds, graded calcarenites and hemipelagic limestones indicating a forereef slope environent. This intercalated
facies belongs to the Buchenstein Formation and interfingers with the Schlern Dolomite. Conodonts from this intercalated slope
facies point to Late Fassanian age. Therefore, the two Middle Triassic depositional sequences of the Gartnerkofel area can
be correlated with the depositional sequences ‘Ladinian 1’ and ‘Ladinian 2’ of the Dolomites, proposed byDe Zanche et al. (1993). A brief comparison with the basinal sequences of similar age of the karawanken Mountains and the Carnia is
presented. 相似文献