Deformation history in part of the Lubec–Belleisle zone of southern New Brunswick

1970 ◽  
Vol 7 (3) ◽  
pp. 748-767 ◽  
Author(s):  
R. L. Brown ◽  
H. Helmstaedt
Keyword(s):  
New Brunswick ◽  
Middle Devonian ◽  
Maximum Principal Stress ◽  
Upper Devonian ◽  
Second Phase ◽  
Lower Carboniferous ◽  
The North ◽  
Principal Compressive Stress ◽  
Two Phases ◽  
Paleozoic Rocks

Rocks of the Proterozoic Coldbrook Group on the north shore of the Bay of Fundy, New Brunswick, are bounded to the north by a major northeast trending fault (Lubec–Belleisle). North of the fault Paleozoic rocks of the Mascarene Group are overlain unconformably by Upper Devonian and Lower Carboniferous strata.Both the Coldbrook and Mascarene Groups have been deformed by three phases of deformation. Deformation of the two Groups was coeval; penetrative fabrics first developed during the Acadian (Middle Devonian) orogeny.Pre-Acadian Paleozoic movements were limited to local or regional uplift with possible attendant warping and/or gentle tilting.Mylonitic fabrics formed in Coldbrook rocks during the first two phases of the Acadian polyphase deformation. These northeast trending s- surfaces lie normal to the direction of maximum finite shortening. Also from the orientation of synmylonization quartz deformation lamellae of the second phase, it is apparent that the local trajectory of the maximum principal stress was normal to the s-surfaces of the mylonites.No evidence for major northeast–southwest strike slip faulting has been found. Fracture analyses in Upper Devonian and Lower Carboniferous rocks in the northeast trending fault zone, point to a northwest trending principal compressive stress.It is contended that the bulk of the ductile strain (first two phases) occurred In response to northwest principal compressive stress during the Middle Devonian, and these stresses were re-established in post-Devonian times, resulting in the development of high angle oblique to dip slip movements on the northeast trending faults.

scholarly journals Charcoal Production During the Norse and Early Medieval Periods in Eyjafjallahreppur, Southern Iceland

Radiocarbon ◽  
2007 ◽  
Vol 49 (2) ◽  
pp. 659-672 ◽  
Author(s):  
M J Church ◽  
A J Dugmore ◽  
K A Mairs ◽  
A R Millard ◽  
G T Cook ◽  
...  
Keyword(s):  
North Atlantic ◽  
Sediment Accumulation ◽  
Early Summer ◽  
Second Phase ◽  
Charcoal Production ◽  
Early Medieval ◽  
Radiocarbon Dates ◽  
The North ◽  
Key Issues ◽  
Two Phases

Timber procurement and the use of woodlands are key issues in understanding the open landscapes of the Norse and Medieval periods in the North Atlantic islands. This paper outlines evidence for the timing and mechanisms of woodland use and deforestation in an area of southern Iceland, which is tracked through the mapping and analysis of charcoal production pits. Precise dating of the use of these charcoal production pits within a Bayesian framework is demonstrated through the combination of tephrochronology, sediment accumulation rates, and multiple radiocarbon dates on the archaeological charcoal. Two phases of charcoal production and woodland exploitation have been demonstrated, the first within the first 2 centuries of settlement (cal AD 870–1050) and the second phase over 100 yr later (cal AD 1185–1295). The implications for using charcoal as a medium for 14C dating in Iceland and the wider North Atlantic are then explored. Archaeobotanical analysis of the charcoal sampled from the pits has indicated that birch roundwood was the dominant wood used, that the roundwood was stripped from larger shrubs/trees in late spring/early summer, and that certain sizes and ages of roundwood were harvested. Finally, the timing of the charcoal production is placed into the wider debate on deforestation across Iceland during the Norse and early Medieval periods.

scholarly journals Revisiting the Paleo Elbe Valley: Reconstruction of the Holocene, Sedimentary Development on Basis of High-Resolution Grain Size Data and Shallow Seismics

Geosciences ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 505
Author(s):  
Svenja Papenmeier ◽  
H. Christian Hass
Keyword(s):  
Grain Size ◽  
High Resolution ◽  
Storm Event ◽  
Second Phase ◽  
The North ◽  
Shallow Seismic ◽  
Scandinavian Ice Sheet ◽  
Western Shore ◽  
Two Phases ◽  
Seismic Reflectors

The Paleo Elbe Valley is the most prominent subsurface structure in the southern North Sea. During the Weichselian (marine isotope stage (MIS) 2), the valley traversed the exposed sea floor and drained the southern margin of the Scandinavian ice sheet. Today the valley is filled with up to 16 m thick sediments, but the responsible processes and drivers remain unknown. To unravel these processes and describe the valley’s evolution with Holocene transgression, we use shallow seismic data and vertical high-resolution grain-size core data. At the base of the western shore, supralittoral fine sands are overlain by a thin layer of clay dated to 9.8 cal. ka BP. The major sediment package consists of marine silt with internal seismic reflectors inclined in a northeastern direction, indicating a sediment transport from the southwest. The valley infill started when the western shore was flooded around 9.6 cal. ka BP and can be divided into two phases. During the first one (9.6–8.1 cal. ka BP) the sedimentation rate was highly driven by wind and waves. The second phase (8.1–5.0 cal. ka BP) was mainly tidal dominated but shows also storm event deposits in the north. Around 5.0 cal. ka BP the valley was almost filled.

scholarly journals Multi-phase tectonic structures in the collision zone of the Kolyma-Omolon microcontinent and the eastern margin of the North Asian craton, Northeastern Russia

2009 ◽  
Vol 4 ◽  
pp. 65-70 ◽  
Author(s):  
A. V. Prokopiev ◽  
V. S. Oxman
Keyword(s):  
Horizontal Displacement ◽  
Strike Slip ◽  
Northeastern Russia ◽  
Second Phase ◽  
Tectonic Structures ◽  
North Asian Craton ◽  
Eastern Margin ◽  
The North ◽  
Two Phases ◽  
Multi Phase

Abstract. The sequence of formation of structures is established in the zone of junction of the eastern margin of the North Asian craton and the northeastern flank of the Kolyma-Omolon microcontinent, in the area of bend of the Kolyma structural loop. Detailed structural studies revealed two phases in the formation of Mesozoic structures – an early thrust phase and a late strike-slip phase. Structures formed during each of the phases are described. Thrust structures are represented by the Setakchan nappe on which the minimum amount of horizontal displacement is estimated at 13–15 km. Later superposed left-lateral strike-slip faults have a north strike. Formation of these latter structures occurred during the second phase of collision between the Kolyma-Omolon microcontinent and the eastern margin of the North Asian craton.

THE GEOLOGY OF THE BONAPARTE GULF BASIN

1966 ◽  
Vol 6 (1) ◽  
pp. 7
Author(s):  
T. J. Brady ◽  
W. Jauncey ◽  
C. Stein
Keyword(s):  
Upper Devonian ◽  
The South ◽  
Continuous Section ◽  
Lower Carboniferous ◽  
North West ◽  
Eastern Margin ◽  
South Eastern ◽  
North East ◽  
The North ◽  
Lower Ordovician

An estimated total of over 20,000 feet of Palaeozoic sediments accumulated in the Bonaparte Gulf Basin. The thickest known continuous section is that in Bonaparte No. 1 Well, abandoned at 10,530 feet in Upper Devonian sandstone and shale. Rocks of the Basin margins are mainly sandstones and limestones (in part reef), whereas a thick shale section has been discovered in the deeper parts. Data from recent seismic surveys indicate that the seaward extension of the Basin is considerable and that a thick pile of sediments is preserved there.The Bonaparte Gulf Basin formed as a result of subsidence of the north-eastern part of the Kimberley Block along fault lines associated with the Halls Creek Mobile Zone. This zone borders the south-eastern margin of the Basin and trends north-east. One basement block, represented by the presentday Pincombe Range, remained relatively high. The Bonaparte Gulf Basin can be divided into two subsidiary basins, the Carlton Basin to the west and north-west and the Burt Range Basin in the east and south-east. The Pincombe Range separates the two.Marine sediments were deposited in the Carlton Basin during the Middle and Upper Cambrian, Lower Ordovician, Upper Devonian and Lower Carboniferous epochs. Angular unconformities have been mapped between the Lower Ordovician and Upper Devonian rocks, and between Upper Devonian and Lower Carboniferous rocks. In the Burt Range Basin, deposition began in the Upper Devonian and continued with minor breaks through the Lower Carboniferous. Faults along the south-eastern margin were active through this period and affected the character of the sediments.Permian sediments are widely distributed and lie with unconformity on older units.

Upper Devonian miospores from the Escuminac Formation, eastern Québec, Canada

1970 ◽  
Vol 7 (1) ◽  
pp. 29-45 ◽  
Author(s):  
Wayne W. Brideaux ◽  
Norman W. Radforth
Keyword(s):  
Middle Devonian ◽  
Russian Platform ◽  
Upper Devonian ◽  
New Combinations ◽  
Lower Carboniferous ◽  
The Third ◽  
Large Size ◽  
Assem Blages ◽  
Small Spore ◽  
Orcadian Basin

Miospores of early Frasnian age are described from the third unit of the Escuminac Formation in eastern Québec, Canada. The assemblage comprises 34 species, including 8 species proposed as new, 2 new combinations, and 12 sparsely represented forms not considered synonymous with previously described species.The assemblage is most closely comparable to a Middle Devonian assemblage from the Orcadian Basin, Scotland. Similarities are also noted with European and Russian assemblages, particularly from the Eifelian–Givetian of the Russian Platform. Except for five long-ranging species, elements of Lower Carboniferous assemblages are lacking. Evidence suggests a transitional nature for this Escuminac assemblage. Miospores of relatively large size, a feature of Middle Devonian assemblages, are present. Marked differentiation of large and small spore types, found in several other Upper Devonian assem blages is absent. Apiculate and anchor-spined species dominate the Escuminac assemblage.

Regional hardening of Upper Cretaceous Chalk in eastern England, UK: trace element and stable isotope patterns in the Upper Cenomanian and Turonian Chalk and their significance

2014 ◽  
Vol 64 (4) ◽  
pp. 419-455 ◽  
Author(s):  
Christopher V. Jeans ◽  
Dee Long ◽  
Xiu-Fang Hu ◽  
Rory N. Mortimore
Keyword(s):  
Manganese Oxides ◽  
Fluid Pressure ◽  
Second Phase ◽  
Pore Fluids ◽  
Carbon And Oxygen Isotopes ◽  
Geological Evidence ◽  
Fine Grained ◽  
The North ◽  
Calcite Cement ◽  
Two Phases

AbstractThe regional hardening of the Late Cenomanian to Early Turonian Chalk of the Northern Province of eastern England has been investigated by examining the pattern of trace elements and stable carbon and oxygen isotopes in the bulk calcite of two extensive and stratigraphically adjacent units each 4 to 5 m thick of hard chalk in Lincolnshire and Yorkshire. These units are separated by a sequence, 0.3-1.3 m thick, of variegated marls and clayey marls. Modelling of the geochemistry of the hard chalk by comparison with the Standard Louth Chalk, combined with associated petrographic and geological evidence, indicates that (1) the hardening is due to the precipitation of a calcite cement, and (2) the regional and stratigraphical patterns of geochemical variation in the cement are largely independent of each other and have been maintained by the impermeable nature of the thin sequence of the clay-rich marls that separate them. Two phases of calcite cementation are recognised. The first phase was microbially influenced and did not lithify the chalk. It took place predominantly in oxic and suboxic conditions under considerable overpressure in which the Chalk pore fluids circulated within the units, driven by variations in compaction, temperature, pore fluid pressure and local tectonics. There is evidence in central and southern Lincolnshire of the loss of Sr and Mgenriched pore fluids to the south during an early part of this phase. The second phase of calcite precipitation was associated with the loss of overpressure in probably Late Cretaceous and in Cenozoic times as the result of fault movement in the basement penetrating the overlying Chalk and damaging the seal between the two chalk units. This greatly enhanced grain pressures, resulting in grain welding and pressure dissolution, causing lithification with the development of stylolites, marl seams, and brittle fractures. Associated with this loss of overpressure was the penetration of the chalk units by allochthonous fluids, rich in sulphate and hydrocarbons, derived probably from the North Sea Basin. Microbial sulphate-reduction under anoxic conditions within these allochthonous fluids has been responsible for dissolving the fine-grained iron and manganese oxides within the chalk, locally enriching the Fe and Mn content of the calcite cement. The possibility is discussed that the pattern of cementation preserved in these regionally hard chalks of Late Cenomanian and Early Turonian age may be different from that preserved in the younger (late Turonian to Campanian) more basinal chalks of eastern England.

On a varcus Zone conodont fauna from the Ilfracombe Slates (Devonian, North Devon)

1979 ◽  
Vol 116 (2) ◽  
pp. 129-134 ◽  
Author(s):  
M. J. Orchard
Keyword(s):  
Middle Devonian ◽  
Upper Devonian ◽  
The North ◽  
Conodont Zone ◽  
German Standard ◽  
Conodont Fauna

SummarySeveral conodont faunas from the Ilfracombe Slates are described and their age discussed. One is referred to the conodont zone of Polygnathus varcus (late Givetian-early Frasnian). The conodonts, the first from the Devonian of North Devon, indicate that, in terms of the German standard, the uppermost Ilfracombe Slates are no younger than basal Manticoceras Stufe in age. The position of the Middle/Upper Devonian boundary within the North Devon sequence is discussed with reference to the limestones of the Combe Martin Slates (the ‘Ilfracombe limestones’), which are regarded here as Middle Devonian in age.

scholarly journals An Interpretation of Late Quaternary Glacial Flow Indicators in the Baie des Chaleurs Region, Northern New Brunswick

2007 ◽  
Vol 43 (2) ◽  
pp. 179-190 ◽  
Author(s):  
A. G. Pronk ◽  
P. T. Bobrowsky ◽  
M. A. Parkhill
Keyword(s):  
New Brunswick ◽  
Late Quaternary ◽  
Ice Sheet ◽  
Field Research ◽  
Published Data ◽  
Second Phase ◽  
Sedimentary Deposits ◽  
The North ◽  
Third Phase ◽  
Late Wisconsinan

ABSTRACT A sequence of late Quaternary geologic events in northern New Brunswick is determined from striation analysis derived from published data, open file reports, and field research conducted by the authors since 1985. These data are integrated with clast provenance and clast fabric trend analysis, as well as information from other studies in the surrounding area. South of the Baie des Chaleurs, a complicated Late Wisconsinan glacial history is preserved in the form of erosive features including nailhead striae, miniature crag-and-tails, and various scars, striations, and fractures. The rarity of sedimentary deposits and datable materials precludes simple stratigraphie interpretation. Based on over 1,000 striation sites, we conclude four major phases of glacial flow affected the area during the Late Wisconsinan: 1) an early flow to the southeast which reflects local Appalachian ice; 2) a second phase of glacial flow to the east indicating a Laurentide ice influence in western New Brunswick; 3) a third phase of glacial flow to the north-northeast, which may represent ice response to drawdown in the Baie des Chaleurs; and 4) a final multidirectional flow indicating localized ice response during the last stages of Late Wisconsinan glaciation. The absence of Canadian Shield erratics in northern New Brunswick is explained in terms of ice streaming along the St. Lawrence channel beneath a southward-flowing Laurentide Ice Sheet. Basal ice debris (including Shield erratics) was apparently truncated and removed by the obliquely flowing ice stream, leaving relatively clean ice in the Ice Sheet as it entered Gaspésie and ultimately New Brunswick.

IV.—The Devonian Rocks of Cornwall

1904 ◽  
Vol 1 (12) ◽  
pp. 587-591
Author(s):  
W. A. E. Ussher
Keyword(s):  
Middle Devonian ◽  
Lower Devonian ◽  
Upper Devonian ◽  
The South ◽  
Ample Evidence ◽  
The North

Sedgwick and Murchison, the Rev. D. Williams, and Dr. Holl, taking the Plymouth limestones as a middle division, placed them below the rocks to the south and above those to the north. The prevalent southerly dips of schistosity were regarded as ample evidence of a downward succession proceeding northward.The Staddon grits and other Lower Devonian rocks were thus placed above the Middle Devonian, and the slates in which I have at various times since 1892 found Upper Devonian fossils (between Menbeniot and St. Budeaux) were relegated to a position below the Middle Devonian.

The Development of Life and Career Skills in 21st Century Test for Undergraduate Students

2022 ◽  
Vol 11 (1) ◽  
pp. 51-68
Author(s):  
Nuanphan Chaiyama ◽  
Nimnoul Kaewpila
Keyword(s):  
Undergraduate Students ◽  
21St Century ◽  
Phase 1 ◽  
Second Phase ◽  
Eastern Region ◽  
Test Items ◽  
The North ◽  
North Eastern ◽  
Two Phases ◽  
Career Skills

<p style="text-align: justify;">The purposes of this study were to explore factors and indicators of life and career skills and to develop a life and career skills in the 21st century test for undergraduate students. This research employed a mixed-method study adopting an exploratory design: instrument development model to generate research tools. This study was divided into two phases; Phase 1 was to explore factors and indicators of life and career skills in 21st century, by using a qualitative method to analyze relevant documents; Phase 2 was the development of a life and career skills in 21st century test by adopting a quantitative method to collect data from students studying in 12 universities of the north-eastern region of Thailand via the test. In the second phase, the data were analyzed by descriptive statistics and Confirmatory Factor Analysis (CFA) Results revealed that the skills consisted of 6 factors and 35 indicators, and the test comprised 105 items. The quality of the test has been examined by five expertise, the reliability of all test items is acceptable, and all 6 factors demonstrated good construct validity. Factor loadings of six factors were 0.7940 -1.7816. This study can be implemented to measure the life and career skills of undergraduate students in any university to obtain data for establishing a policy and plans for maximizing students’ potential to achieve their careers and a happy living in 21st century after their graduation.</p>

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