Cretaceous–Early Tertiary Rift Basin of Baffin Bay—Continental Drift Without Sea-Floor Spreading1

1973 ◽  
Author(s):  
Rudolf Martin
Keyword(s):  
Continental Drift ◽  
Rift Basin ◽  
Sea Floor ◽  
Baffin Bay ◽  
Early Tertiary ◽  
Sea Floor Spreading

Baffin Bay Composite Tectono-Sedimentary Element

2021 ◽  
pp. M57-2016-7
Author(s):  
Paul C. Knutz ◽  
Ulrik Gregersen ◽  
Christopher Harrison ◽  
Thomas A. Brent ◽  
John R. Hopper ◽  
...  
Keyword(s):  
Structural Complexity ◽  
Large Data ◽  
Source Rocks ◽  
Sea Floor ◽  
Baffin Bay ◽  
Early Oligocene ◽  
Oceanic Basin ◽  
Late Paleocene ◽  
Transitional Crust ◽  
Sea Floor Spreading

AbstractBaffin Bay formed as a result of continental extension during the Cretaceous, which was followed by sea floor spreading and associated plate drift during the early to middle Cenozoic. Formation of an oceanic basin in the central part of Baffin Bay may have begun from about 62 Ma in tandem with Labrador Sea opening but the early spreading phase is controversial. Plate-kinematic models suggests that from Late Paleocene the direction of sea floor spreading changed to N-S generating strike-slip movements along the transform lineaments, e.g. the Ungava Fault Zone and the Bower Fracture Zone, and structural complexity along the margins of Baffin Bay. The Baffin Bay Composite Tectono-Sedimentary Element (CTSE) represents a 3-7 km thick Cenozoic sedimentary and volcanic succession that has deposited over oceanic and rifted continental crust since active seafloor spreading began. The CTSE is subdivided into 5 seismic mega-units that have been identified and mapped using a regional seismic grid tied to wells and core sites. Thick clastic wedges of likely Late Paleocene to Early Oligocene age (mega-units E and D2) were deposited within basins floored by newly formed oceanic crust, transitional crust, volcanic extrusives and former continental rift basins undergoing subsidence. The middle-late Cenozoic is characterized by fluvial-deltaic sedimentary systems, hemipelagic strata and aggradational sediment bodies deposited under the influenced of ocean currents (mega-units D1, C and B). The late Pliocene to Pleistocene interval (mega-unit A) displays major shelf margin progradation associated with ice-sheet advance-retreat cycles resulting in accumulation of trough-mouth fans and mass-wasting deposits products in the oceanic basin. The Baffin Bay CTSE has not produced discoveries although a hydrocarbon potential may be associated with Paleocene source rocks. Recent data have improved the geological understanding of Baffin Bay although large data and knowledge gaps remain.

Geophysical studies on the eastern continental margin of Baffin Bay and in Lancaster Sound

1977 ◽  
Vol 14 (9) ◽  
pp. 1991-2001 ◽  
Author(s):  
H. R. Jackson ◽  
C. E. Keen ◽  
D. L. Barrett
Keyword(s):  
Structural Characteristics ◽  
Seismic Refraction ◽  
Continental Drift ◽  
Baffin Island ◽  
Seismic Reflection Data ◽  
Baffin Bay ◽  
Reflection Data ◽  
Basement High ◽  
Seismic Refraction Data ◽  
Sea Floor Spreading

The results of three crustal refraction lines on the western margin of Baffin Bay and one in Lancaster Sound are described. The refraction measurements in Baffin Bay along with earlier refraction, gravity, magnetic, and seismic reflection data are used to define the boundary between continental and oceanic crust. The results suggest that the transition from continental to oceanic material takes place in about 30 km. The seismic refraction data also suggest a sedimentary basin on the continental shelf with at least 6 km thickness of sediment which, however, thins rapidly near Baffin Island. This basin is truncated under the slope by either a basement high or carbonate rocks. Lancaster Sound is filled by about 10 km of sediments that could be either of Mesozoic or Paleozoic age based on comparisons with velocities in nearby wells. The sedimentary and structural characteristics of Lancaster Sound are discussed and related to the concepts of sea-floor spreading and continental drift.

Tuzo Wilson and the acceptance of pre-Mesozoic continental drift

2014 ◽  
Vol 51 (3) ◽  
pp. 197-207 ◽  
Author(s):  
Paul F. Hoffman
Keyword(s):  
Continental Drift ◽  
Early Experience ◽  
Canadian Shield ◽  
Sea Floor ◽  
Geologic Time ◽  
Sea Floor Spreading ◽  
Continental Accretion

Tuzo Wilson’s well-known pre-1961 opposition to continental drift stemmed from his early experience as a geologist in the Appalachians and the Canadian Shield, which convinced him that orogenesis did not change drastically over geologic time. Conversely, Taylor (in 1910) and Wegener (in 1912) hypothesized that continental drift began in Cenozoic or Mesozoic time. Between 1949 and 1960, Tuzo Wilson with Adrian Scheidegger developed a quasi-uniformitarian model of progressive continental accretion around fixed Archean nuclei. Tuzo abruptly jettisoned this model in 1961 when, under pressure from paleomagnetic evidence for continental drift and a nascent concept of sea-floor spreading, he finally entertained the possibility of pre-Mesozoic as well as younger continental drift. He immediately found it a superior fit to Appalachian and Shield geology, while his uniformitarian conviction remained intact. Tuzo had blinded himself to the evidence for continental drift so long as he confined it to Taylor or Wegener’s conception. In continental drift operating continuously over geologic time, he found a theory he could eagerly accept.

Seismicity of the Baffin Bay region

1974 ◽  
Vol 64 (1) ◽  
pp. 87-98
Author(s):  
Anthony Qamar
Keyword(s):  
Upper Mantle ◽  
Baffin Island ◽  
Sea Floor ◽  
Baffin Bay ◽  
Hypocenter Determination ◽  
Joint Hypocenter Determination ◽  
Glacial Rebound ◽  
Sea Floor Spreading ◽  
Linear Trends ◽  
Northeast Coast

abstract Twenty-eight earthquakes in the Baffin Bay region have been relocated using the method of Joint Hypocenter Determination. The revised locations indicate two parallel, linear trends, one along the northeast coast of Baffin Island and the other in the western part of Baffin Bay. The seismicity does not appear to be controlled by glacial rebound but may be a remnant of sea-floor spreading which occurred 40 to 60 m.y. ago. Early P arrivals at near seismograph stations (Δ < 20°) can be explained by a high-velocity (8.5 km/sec) upper mantle in the Baffin region.

scholarly journals A Geologist Reflects on a Long Career

2018 ◽  
Vol 46 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Dan MKenzie
Keyword(s):  
Plate Tectonics ◽  
Continental Drift ◽  
Temperature Structure ◽  
Earth’S Gravity Field ◽  
Plate Motions ◽  
Sea Floor ◽  
Long Wavelength ◽  
Geological Processes ◽  
The Earth ◽  
Sea Floor Spreading

Fifty years ago Jason Morgan and I proposed what is now known as the theory of plate tectonics, which brought together the ideas of continental drift and sea floor spreading into what is probably their final form. I was twenty-five and had just finished my PhD. The success of the theory marked the beginning of a change of emphasis in the Earth sciences, which I have spent the rest of my career exploring. Previously geophysicists had principally been concerned with using ideas and techniques from physics to make measurements. But the success of plate tectonics showed that it could also be used to understand and model geological processes. This essay is concerned with a few such efforts in which I have been involved: determining the temperature structure and rheology of the oceanic and continental lithosphere, and with how mantle convection maintains the plate motions and the long-wavelength part of the Earth's gravity field. It is also concerned with how such research is supported.

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