Pleistocene and Recent sediments of northern Placentia Bay, Newfoundland

1976 ◽  
Vol 13 (10) ◽  
pp. 1386-1392 ◽  
Author(s):  
Charles F. Stehman
Keyword(s):  
Sedimentary Facies ◽  
Distribution Patterns ◽  
Surficial Sediments ◽  
Facies Distribution ◽  
Marine Deposits ◽  
Placentia Bay ◽  
Recent Sediments

Study of the sediments found in northern Placentia Bay, Newfoundland, using MS-26-B echosounder profiles and 87 grab samples, reveals that sediments in that area are derived principally from glacial sources. Sediment facies distribution patterns are contrastingly different in different regions of the bay. The data suggest that surficial sediments associated with glacial drift, transgressive marine deposits, and modern sedimentation occur in a complex mosaic of seven facies distributed throughout the region. There is some evidence of relationships between sedimentary facies and both bathymetry and geography.

The Investigation between Sedimentary Facies of Middle Cambrian and the Characters of Volcanic Rock, in Wenshan, Yunnan Province

2013 ◽  
Vol 652-654 ◽  
pp. 2560-2565
Author(s):  
Jian Guo Huang ◽  
Run Sheng Han ◽  
Tao Ren ◽  
Zhi Qiang Li
Keyword(s):  
Trace Element ◽  
Volcanic Rock ◽  
Sedimentary Facies ◽  
Distribution Patterns ◽  
Major Elements ◽  
Middle Cambrian ◽  
Ree Distribution ◽  
Tholeiite Series ◽  
Back Arc ◽  
The Eu

The Middle Cambrian Tianpeng Formation volcanic rock, which was found in Baishiyan area in Wenshan recently, is the typical basalt. Through the research of Tianpeng Formation Sedimentary Enviroment and analysis of the geochemistry which includes the major elements, REE and Trace Element in the volcanic rock, SiO2 is 45.78-54.88%, total alkali (alk)=1.22-4.97 and K2O/Na2O=0.03-0.53, we can say that it should be tholeiite series. ∑REE=48.60-157.11ppm,LREE/HREE7.56-9.48,δEu0.40-1.05.REE distribution patterns show oblique to the HREE side and enrichment in LREE , the Eu anomaly is not obvious. We can see from the Trace Element Correlogram that the volcanic in this area is formed from the intiaplate basalt environment. The Tianpeng Formation in this area is clastic rock in a shallow sea and a basin facies and also is the deposit of flysch-simiflyschoid of siliceous and carbonate rock. Also, it deposit with the some undercompensation basin like laminated striation structure. All of those reflect that the structure background of the Middle Cambrian in Wenshan area has strong tensive back-arc spreading.

Amino acids and hexosamines in the Hess Rise core during the past 220,000 years

2003 ◽  
Vol 60 (3) ◽  
pp. 394-403 ◽  
Author(s):  
Lallan Prasad Gupta ◽  
Hodaka Kawahata
Keyword(s):  
Amino Acids ◽  
Surface Waters ◽  
Late Quaternary ◽  
Distribution Patterns ◽  
Quaternary Sediments ◽  
Core Sediment ◽  
The Past ◽  
Calcareous Plankton ◽  
Recent Sediments ◽  
Glacial Periods

AbstractCore sediment samples collected from the Hess Rise, North Pacific, were analyzed for 20 common amino acids (AA) and two hexosamines (HA) to understand the relation between glacial–interglacial variations and deposition/preservation of sedimentary organic matter (OM). The sediments are predominantly carbonaceous (carbonates 35–80%). AA-based parameters—aspartic acid/glycine ratio and serine+threonine relative mole content—suggest that calcareous plankton was the major source of OM in these sediments. This inference is supported by the similarity in distribution patterns of AA and HA contents with that of organic carbon. Low values of AA/HA and glucosamine/galactosamine ratios (average 4.4 and 1.1, respectively) imply that much of the planktonic OM was replaced by microbial OM. The relative molar concentration of two nonprotein AA (β-alanine and γ-aminobutyric acid) varied with age of sediments; i.e., they were less abundant in recent sediments and more abundant in the oldest sediments. This trend is an indicator of extremely slow but continuous enzymatic degradation of proteinaceous OM within the sediments. So far, bulk OM has been believed to be one of the best proxies for estimation of primary productivity. However, it may be an underestimate, even for the late Quaternary sediments. Comparison of AA and HA content variations with SPECMAP stack revealed their enhanced deposition and preservation during glacial periods relative to interglacial periods. This, in turn, affected not only the planktonic production in surface waters but also the benthic community, including bacteria on the seafloor.

Physicochemical and geotechnical characteristics of recent Saguenay Fjord sediments

1988 ◽  
Vol 25 (2) ◽  
pp. 382-388 ◽  
Author(s):  
Jacques Locat ◽  
Serge Leroueil
Keyword(s):  
Shear Strength ◽  
Sedimentary Environment ◽  
Physicochemical Characteristics ◽  
Organic Content ◽  
First Order ◽  
Marine Deposits ◽  
Geotechnical Characteristics ◽  
Saguenay Fjord ◽  
Recent Sediments ◽  
Fjord Sediments

In the spring of 1985 the first goetechnical reconnaissance of recent Saguenay Fjord sediments took place, in which were recorded the two Saint-Jean-Vianney slides of 1663 and 1971. Cores from the upper part of the fjord were tested onboard the ship and in the laboratory. The mineralogy of the recent sediments is like that of the raised marine deposits of the area, except for the organic content, which is higher. The microstructure of the sediment is quite typical of flocculated marine soils. The freshly sedimented soil, in its sedimentary environment, has gained strength and sensitivity (up to 12) in excess of what is usually expected for such material. It has been concluded that the physicochemical characteristics of the sediment, such as depicted by its initial plasticity (before leaching), are first-order parameters in the source of apparent overconsolidation and structuration. Key words: recent sediments, shear strength, sensitivity, consolidation, structuration, microstructure, landslide, physicochemistry, mineralogy.

Tectonic–sedimentary interplay of a confined deepwater system in a foreland basin setting: the Pennsylvanian lower Atoka Formation, Ouachita Mountains, U.S.A.

2021 ◽  
Vol 91 (7) ◽  
pp. 683-709
Author(s):  
Pengfei Hou ◽  
Lesli J. Wood ◽  
Zane R. Jobe
Keyword(s):  
Foreland Basin ◽  
Structural Data ◽  
Distribution Patterns ◽  
Sediment Supply ◽  
Ouachita Mountains ◽  
Submarine Fan ◽  
Facies Distribution ◽  
Submarine Fans ◽  
Basin Morphology ◽  
Complex Settings

ABSTRACT Submarine fans deposited in structurally complex settings record important information on basin evolution and tectonic–sedimentary relationships but are often poorly preserved in outcrops due to syndepositional and post depositional deformation. This study aims to understand the influence of tectonics on the deposition of the synorogenic Pennsylvanian lower Atoka submarine fan system deposited in a structurally complex foreland basin during the Ouachita orogeny. This study is a synthesis of new outcrop stratigraphic data as well as published stratigraphic and structural data. The lower Atoka crops out in the Ouachita Mountains and the southern Arkoma Basin and is divided into three structural–depositional zones: the foredeep, the wedge top, and the continental foreland. The mean paleoflow is axial, and each zone exhibits unique patterns in facies distribution. The foredeep consists of two fan systems, a large westward-prograding fan that exhibits significant longitudinal and lateral facies changes, and a small eastward-prograding fan on the western part. The wedge top consists of a westward-prograding fan that exhibits subtle longitudinal facies change. The continental foreland consists of small slope fan systems along the northern and western margins. By comparing to basin morphology and structural styles, we interpret the facies distribution patterns in the three zones as the result of different combinations of lateral structural confinement, axial and lateral sediment supply, and paleogeography. This study provides an improved and comprehensive understanding of the lower Atoka deepwater system and has implications for deciphering the tectonic–sedimentary relationships in laterally confined submarine fan systems.

Sign in / Sign up

Export Citation Format

Share Document