Results 51 to 60 of about 1,497,171 (212)

Evolution of the Ordovician top boundary and its relationship to reservoirs' development, Ordos Basin

open access: yesPetroleum Exploration and Development, 2012
The control of structural evolution on the development of different types of Ordovician reservoirs in the Ordos Basin is discussed by studying the evolution of the Ordovician top boundary in geological times, and the mechanisms of formation and evolution
Xinquan RAN   +5 more
doaj   +1 more source

Orthodentine‐osteodentine and osteocytic‐anosteocytic transition inferred from Silurian stem chondrichthyan dermal jawbones with ever‐white teeth overgrown by brown denticles

open access: yesDevelopmental Dynamics, EarlyView.
Abstract Background The dentigerous jawbones of a 423‐million‐year‐old stem chondrichthyan (ischnacanthid acanthodian) carry a characteristic combination of multi‐row non‐shedding white teeth with brownish overgrowing denticles. The color distinction makes it a good model for observing the interaction between two odontode lineages, but the nature of ...
Jia‐Cih Kang   +3 more
wiley   +1 more source

Post‐Stimulation Hydraulic Response and Productivity Constraints of a Low‐Productivity Carbonate Geothermal Well in the Small Intramontane Basin, Beijing Piedmont, North China

open access: yesEnergy Science &Engineering, EarlyView.
Formed ~1.4 Ga, the carbonate reservoir of the Jixian System is a key geothermal reservoir in northern China. Differential basin–mountain evolution since the Cenozoic led to distinct reservoir‐forming histories; consequently, this same reservoir shows marked productivity contrasts between intramontane basins and the large rift Bohai Bay Basin ...
Chuanqing Zhu   +6 more
wiley   +1 more source

The cephalopods of the Boda Limestone, Late Ordovician, of Dalarna, Sweden [PDF]

open access: yes, 2013
The late Katian, Late Ordovician Boda Limestone of Dalarna, Sweden contains a rich cephalopod assemblage. The assemblage consists of 61 species, in 31 genera, comprising almost all major Ordovician cephalopod orders.
Kröger, Björn   +3 more
core   +1 more source

Upper Ordovician ecology of the central Appalachians [PDF]

open access: yes, 1970
The upper Reedsville Formation and portions of equivalent Martinsburg strata (Upper Ordovician) in the central Appalachians provide one of the earliest known examples of a prolific clastic-facies invertebrate fauna with a distinctly modern aspect…
Bretsky, Peter William, Jr.
core   +1 more source

Carbon and oxygen isotope variation and its implication for marine sequence: A case study of Ordovician in Tarim Basin

open access: yesPetroleum Research, 2017
Carbon and oxygen isotopes of marine carbonate rocks or fossil shells could indicate global sea-level relative change. Generally, heavier carbon isotopes or lighter oxygen isotopes reflected rise of global sea-level relative changes, and vice versa.
Zongju Zhao, Jianguo Wang, Peixi Wang
doaj   +1 more source

A Reassessment of Petrochemistry of ~1.2 Ga Tonalitic Rocks of the Northern Tugela Terrane, Natal Metamorphic Belt, South Africa: Further Constraints on the Evolution of This Belt

open access: yesGeological Journal, EarlyView.
Our petrochemical studies on ~1.2 Ga granitoids of the Natal Metamorphic Belt, South Africa, do not suggest any property similar to Phanerozoic‐style subduction‐related granitoids. Plot of Kotongweni Tonalite in Y versus Sr diagram (after Moyen 2011), note that most samples have Sr/Y < 50.
Palesa Leuta   +2 more
wiley   +1 more source

Bryozoan‐Rich Carbonate Units of the Erfoud Area (SE Morocco) Record Latest Katian to Early Hirnantian Interglacial Intervals

open access: yesGeological Journal, EarlyView.
In this study, we re‐examine the depositional architecture of the Erfoud limestone in Morocco. Introducing new biostratigraphic constraints from chitinozoan assemblages, we show that Katian to Hirnantian bryozoan‐pelmatozoan meadows reflect flooding events linked to a series of interglacial transgressions known to have occurred immediately prior to the
Philippe Razin   +4 more
wiley   +1 more source

Testing for Burden in a Macroevolutionary System

open access: yesJournal of Experimental Zoology Part B: Molecular and Developmental Evolution, EarlyView.
Evolutionary changes in the fundamental components of the bivalve body plan are not restricted to the early part of their evolutionary history. ABSTRACT The traits defining organismal body plans are expected to acquire burden, approaching invariance as they accumulate characters that depend on them, developmentally and functionally.
David Jablonski, Stewart M. Edie
wiley   +1 more source

New geochronological constraints on Late Pleistocene glaciation in the southern Cadí Massif, SE Pyrenees

open access: yesJournal of Quaternary Science, EarlyView.
ABSTRACT The Cadí Massif (42°17′09″ N, 1°38′11″ E; 2649 m a.s.l.) in the southeastern Pyrenees preserves clear evidence of Late Pleistocene glaciation, although previous research has focused almost exclusively on its northern slope. By contrast, the southern slope has remained largely unexplored.
M. Oliva   +5 more
wiley   +1 more source

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