Ordovician strata on the southeastern Baffin Island shelf revealed by shallow drilling

1977 ◽  
Vol 14 (8) ◽  
pp. 1925-1939 ◽  
Author(s):  
B. MacLean ◽  
L. F. Jansa ◽  
R. K. H. Falconer ◽  
S. P. Srivastava
Keyword(s):  
Organic Material ◽  
Depositional Environments ◽  
Baffin Island ◽  
Island Shelf ◽  
Open Shelf

Cores of the bedrock underlying the southeastern Baffin Island shelf were recovered by underwater electric rock core drill at four localities. Cores from three of the localities consist of olive gray to dark yellow–brown slightly dolomitic limestones, in part burrowed and containing flat pebble conglomerate and breccia. Fragments of trilobites, brachiopods, crinoids, and other fossils including coral are present. Radiolarian wackestone was found at one locality where the rock also contains finely disseminated organic material. The strata have been assigned an Ordovician age (Caradoc) based on identification of chitinozoa, scolecodonts, and coral material. Depositional environments included shallow intertidal–subtidal, open shelf, and outer littoral–epibathyal. Core from the fourth locality is Precambrian biotite gneiss.Seismic reflection and magnetic profiles have been used for correlation of the corehole data and to outline the geology of part of the southeastern Baffin Island shelf.

Tertiary basalts of western Davis Strait: bedrock core samples and geophysical data

1978 ◽  
Vol 15 (5) ◽  
pp. 773-780 ◽  
Author(s):  
B. MacLean ◽  
R. K. H. Falconer ◽  
D. B. Clarke
Keyword(s):  
Magnetic Anomaly ◽  
Seismic Reflection ◽  
Volcanic Rocks ◽  
Geophysical Data ◽  
Baffin Island ◽  
Main Area ◽  
Fine Grained ◽  
Core Samples ◽  
Davis Strait ◽  
Island Shelf

Short bedrock cores of basalt were recovered at two localities on the Baffin Island shelf, 33 and 89 km southeast of Cape Dyer. The volcanic rocks underlying these sites have a surface extent of some 8000 km2 as outlined by seismic reflection and magnetic anomaly profiles. Similar rocks are inferred to occur at two smaller offshore areas south of the main area. The offshore occurrences are both more continuous and much larger than the onshore basalt areas of eastern Baffin Island.The core samples appear to have been cut from single flows consisting of fine-grained microporphyritic basalts with olivine as the principal phenocryst phase. Although having distinct differences from one another in terms of texture and degree of alteration, the samples from the three drill stations bear similarities to the Baffin Island basalts that suggest a close petrogenetic relationship may exist between the onshore and offshore basalts. However, in contrast to the subaqueously erupted volcanic breccias of onshore Baffin Island and West Greenland the offshore samples contain little evidence of glass, suggesting the possibility that the latter may have been erupted in a subaerial environment.

scholarly journals Volume, Freshwater, and Heat Fluxes through Davis Strait, 2004–05*

2011 ◽  
Vol 41 (3) ◽  
pp. 429-436 ◽  
Author(s):  
B. Curry ◽  
C. M. Lee ◽  
B. Petrie
Keyword(s):  
Heat Fluxes ◽  
First Year ◽  
Baffin Island ◽  
Fram Strait ◽  
The West ◽  
Baffin Bay ◽  
Freshwater Fluxes ◽  
Davis Strait ◽  
Island Shelf ◽  
Southward Transport

Abstract Davis Strait volume [−2.3 ± 0.7 Sv (1 Sv ≡ 106 m3 s−1); negative sign indicates southward transport], freshwater (−116 ± 41 mSv), and heat (20 ± 9 TW) fluxes estimated from objectively mapped 2004–05 moored array data do not differ significantly from values based on a 1987–90 array but are distributed differently across the strait. The 2004–05 array provided the first year-long measurements in the upper 100 m and over the shelves. The upper 100 m accounts for 39% (−0.9 Sv) of the net volume and 59% (−69 mSv) of the net freshwater fluxes. Shelf contributions are small: 0.4 Sv (volume), 15 mSv (freshwater), and 3 TW (heat) from the West Greenland shelf and −0.1 Sv, −7 mSv, and 1 TW from the Baffin Island shelf. Contemporaneous measurements of the Baffin Bay inflows and outflows indicate that volume and freshwater budgets balance to within 26% and 4%, respectively, of the net Davis Strait outflow. Davis Strait volume and freshwater fluxes nearly equal those from Fram Strait, indicating that both are significant Arctic freshwater pathways.

Activation of a small ephemeral lake in southern Jordan during the last full glacial period and its paleoclimatic implications

2017 ◽  
Vol 88 (1) ◽  
pp. 98-109 ◽  
Author(s):  
Gentry A. Catlett ◽  
Jason A. Rech ◽  
Jeffrey S. Pigati ◽  
Mustafa Al Kuisi ◽  
Shanying Li ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Material ◽  
Radiocarbon Dating ◽  
Arabian Peninsula ◽  
Eastern Mediterranean ◽  
Depositional Environments ◽  
Glacial Period ◽  
Ephemeral Lakes ◽  
Low Concentrations ◽  
Arid And Semiarid

AbstractPlayas, or ephemeral lakes, are one of the most common depositional environments in arid and semiarid lands worldwide. Playa deposits, however, have mostly been avoided as paleoclimatic archives because they typically contain exceptionally low concentrations of organic material, making14C dating difficult. Here, we describe a technique for concentrating organic matter in sediments for radiocarbon dating and apply it to playa sediments recovered from a 2.35 m sediment core from a small playa in southern Jordan. Based on14C ages of the organic concentrate fraction, the playa was active from ~29 to 21 ka, coincident with the last major high stand of Paleolake Lisan and wet conditions recorded by other paleoclimatic proxies in the southernmost Levant during the last full glacial period (35–20 ka). The timing and spatial pattern of these records suggests that the increased moisture was likely derived from more frequent and deeper eastern Mediterranean (EM) cyclones associated with the intensification of the westerlies. The presence of full glacial pluvial deposits in southern Jordan (29°N), and the lack of similarly aged deposits in the northern Arabian Peninsula to the south, suggests that the southerly limit of the incursion of EM cyclones during last full glacial period was ~28°N.

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