Reply to “Mega-highstand or megatsunami? Discussion of McMurtry et al. “Elevated marine deposits in Bermuda record a late Quaternary megatsunami”: Sed. Geol. 200 (2007) 155–165” by Paul J. Hearty and Storrs L. Olson

2008 ◽  
Vol 203 (3-4) ◽  
pp. 313-319 ◽  
Author(s):  
Gary M. McMurtry ◽  
David R. Tappin ◽  
Peter N. Sedwick ◽  
Ian Wilkinson ◽  
Jan Fietzke ◽  
...  
Keyword(s):  
Late Quaternary ◽  
Marine Deposits

Stratigraphy and timing of eolianite deposition on Rottnest Island, Western Australia

2003 ◽  
Vol 60 (2) ◽  
pp. 211-222 ◽  
Author(s):  
Paul J. Hearty
Keyword(s):  
North Atlantic ◽  
Late Quaternary ◽  
The West ◽  
Oxygen Isotope Stage ◽  
Amino Acid Racemization ◽  
Marine Deposits ◽  
The North ◽  
The North Atlantic ◽  
Radiometric Ages ◽  
Mis 5E

AbstractOver 100 whole-rock amino acid racemization (AAR) ratios from outcrops around Rottnest Island (32.0° S Latitude near Perth) indicate distinct pulses of eolian deposition during the late Quaternary. Whole-rock d-alloisoleucine/l-isoleucine (A/I) ratios from bioclastic carbonate deposits fall into three distinct modal classes or “aminozones.” The oldest, Aminozone E, averages 0.33 ± 0.04 (n = 21). Red palaeosol and thick calcrete generally cap the Aminozone E deposits. A younger Aminozone C averages 0.22 ± 0.03 (n = 63); comprising two submodes at 0.26 ± 0.01 (n = 14) and 0.21 ± 0.02 (n = 49). Multiple dune sets of this interval are interrupted by relatively weak, brown to tan “protosols.” A dense, dark brown rendzina palaeosol caps the Aminozone C succession. Ratios from Holocene dune and marine deposits (“Aminozone A”) center on 0.11 ± 0.02 (n = 15), comprising submodes of 0.13 ± 0.01 (9) and 0.09 ± 0.01 (6). Calibration of A/I averages from Aminozones E and A are provided by U/Th and 14C radiometric ages of 125,000 yr (marine oxygen isotope stage (MIS) 5e and 2000–6000 14C yr B.P. (MIS 1), respectively. The whole-rock A/I results support periodic deposition initiated during MIS 5e, continuing through MIS 5c, and then peaking at the end of MIS 5a, about 70,000–80,000 yr ago. Oceanographic evidence indicates the area was subjected to much colder conditions during MIS 2–4 (10,000 to 70,000 yr ago), greatly slowing the epimerization rate. Eolianite deposition resumed in the mid Holocene (∼6000 yr ago) up to the present. The A/I epimerization pathway constructed from Rottnest Island shows remarkable similarity to that of Bermuda in the North Atlantic (32° N Latitude). These findings suggest that, like Bermuda, the eolian activity on Rottnest occurred primarily during or shortly after interglacial highstands when the shoreline was near the present datum, rather than during glacial lowstands when the coastline was positioned 10–20 km to the west.

scholarly journals Circum-Antarctic coastal environmental shifts during the Late Quaternary reflected by emerged marine deposits

1998 ◽  
Vol 10 (3) ◽  
pp. 345-362 ◽  
Author(s):  
Paul A. Berkman ◽  
John T. Andrews ◽  
Svante Björck ◽  
Eric A. Colhoun ◽  
Steven D. Emslie ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Late Quaternary ◽  
Marine Species ◽  
Coastal Areas ◽  
The Arctic ◽  
Marine Habitat ◽  
Marine Deposits ◽  
Quaternary Climate ◽  
Antarctic Marine ◽  
The Antarctic

This review assesses the circumpolar occurrence of emerged marine macrofossils and sediments from Antarctic coastal areas in relation to Late Quaternary climate changes. Radiocarbon ages of the macrofossils, which are interpreted in view of the complexities of the Antarctic marine radiocarbon reservoir and resolution of this dating technique, show a bimodal distribution. The data indicate that marine species inhabited coastal environments from at least 35 000 to 20 000 yr BP, during Marine Isotope Stage 3 when extensive iceberg calving created a ‘meltwater lid’ over the Southern Ocean. The general absence of these marine species from 20 000 to 8500 yr BP coincides with the subsequent advance of the Antarctic ice sheets during the Last Glacial Maximum. Synchronous re-appearance of the Antarctic marine fossils in emerged beaches around the continent, all of which have Holocene marine-limit elevations an order of magnitude lower than those in the Arctic, reflect minimal isostatic rebound as relative sea-level rise decelerated. Antarctic coastal marine habitat changes around the continent also coincided with increasing sea-ice extent and outlet glacial advances during the mid-Holocene. In view of the diverse environmental changes that occurred around the Earth during this period, it is suggested that Antarctic coastal areas were responding to a mid-Holocene climatic shift associated with the hydrological cycle. This synthesis of Late Quaternary emerged marine deposits demonstrates the application of evaluating circum-Antarctic phenomena from the glacial-terrestrial-marine transition zone.

A provisional aminostratigraphical framework for late Quaternary marine deposits in Buenos Aires province, Argentina

1995 ◽  
Vol 128 (1-2) ◽  
pp. 85-104 ◽  
Author(s):  
M.L. Aguirre ◽  
D.Q. Bowen ◽  
G.A. Sykes ◽  
R.C. Whatley
Keyword(s):  
Buenos Aires ◽  
Late Quaternary ◽  
Buenos Aires Province ◽  
Marine Deposits

scholarly journals Quaternary palaeoceanography and palaeogeography in northern Denmark: a review of results from the Skagen cores

1996 ◽  
Vol 43 ◽  
pp. 22-31
Author(s):  
Karen Luise Knudsen ◽  
Keld Conradsen ◽  
, Susanne Heier Nielsen ◽  
Marit-Solveig Seidenkrantz
Keyword(s):  
North Atlantic ◽  
Late Quaternary ◽  
Climatic Changes ◽  
Last Interglacial ◽  
North Atlantic Region ◽  
Atlantic Region ◽  
Radiocarbon Dates ◽  
Marine Deposits ◽  
The North ◽  
Late Weichselian

Palaeoenvironmental reconstructions from the Skagen record contribute to the understanding of Late Quatemary climatic changes and variations in the oceanographic circulation pattem in the entire North Atlantic region. The Skagen cores penetrated c. 192 m of Quatemary sediments comprising two marine Late Quaternary records: A 7 m marine unit (185.3-178.3 m) comprised the entire last interglacial, including its lower and upper transitions (Late Saalian-Eemian-Early Weichselian), while the upper 132 m of marine deposits covered the last about 15,000 years from the Late Weichselian through the Holocene, including the Pleistocene-Holocene transition. Results from the study of lithology, foraminifera, stable isotope measurements and radiocarbon dates are reviewed while emphasizing the most important contributions to the general understanding of the North Atlantic Quatemary history

scholarly journals PALEOECOLOGICAL HABITAT OF THE LATE QUATERNARY MOLLUSCS OF THE NORTHERN FORE-CASPIAN LOWLAND ON THE EXAMPLE OF THE KOSIKA 1 LOCALITY

2015 ◽  
Vol 4 (2) ◽  
pp. 120-123
Author(s):  
Regina Navkatova Miftakhova ◽  
Guzel Anvarovna Danukalova
Keyword(s):  
River Flow ◽  
Late Quaternary ◽  
Fluvial Deposits ◽  
Marine Deposits ◽  
Marine Mollusc ◽  
Layer 2 ◽  
Layer 4 ◽  
Caspian Lowland ◽  
Mollusc Species ◽  
Shell Fragments

Investigations of the Middle-Late Neopleistocene deposits of the Kosika 1 locality and studied malacological complexes permit to understand changes of the main geological events of the territory and to identify molluscs palaeoecologihal habitats. Brakishwater and freshwater lakes existed on the territory after Early Khazarian Sea regression (beginning of the Late Neopleistocene; layer 1). Marine deposits accumulated during Late Khazarian Sea transgression (first half of the Late Neopleistocene; layer 2). Big river (Paleo-Volga) existed after the regression of the Late Khazarian Sea. This river flow to the south in the direction of the coastline retreatment. Fluvial deposits prove river existence (layer 4). Marine deposits with special key mollusc species accumulated during the Khvalynian Sea transgression. Again, river existed after regression of this sea. Alluvium is on the top of the Khvalynian section, it is contain rich complex of the freshwater and marine mollusc species (layer 5). Fluvial-marine deposits form the underwater delta, which accumulated during Late Khvalynian time. These deposits contain shell fragments of freshwater and marine mollusc species. Deposits of the underwater delta form in the relief elongated hills, which are known as Ber bugor among geomorphologists.

Elevated marine deposits in Bermuda record a late Quaternary megatsunami

2007 ◽  
Vol 200 (3-4) ◽  
pp. 155-165 ◽  
Author(s):  
Gary M. McMurtry ◽  
David R. Tappin ◽  
Peter N. Sedwick ◽  
Ian Wilkinson ◽  
Jan Fietzke ◽  
...  
Keyword(s):  
Late Quaternary ◽  
Marine Deposits

Late Quaternary glacial and sea-level events, Clements Markham Inlet, northern Ellesmere Island, Arctic Canada

1986 ◽  
Vol 23 (9) ◽  
pp. 1343-1355 ◽  
Author(s):  
Jan Bednarski
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Ellesmere Island ◽  
Glacial Retreat ◽  
Radiocarbon Dates ◽  
Ice Caps ◽  
Marine Deposits ◽  
Ice Retreat ◽  
Level Ice ◽  
Small Valley

Clements Markham Inlet cuts into the Grant Land Mountains of the northernmost coast of Ellesmere Island. The head of the inlet is bounded on three sides by mountain ice caps that surround lowlands mantled by extensive raised marine deposits. Fieldwork and mapping of late Quaternary sediments were used to determine the limits of past glaciations and the nature of ice retreat from the inlet head. Forty-five radiocarbon dates on driftwood and marine shells provide a deglacial chronology and document related sea-level adjustments.High-level ice-marginal meltwater channels and mountain summit erratics indicate that ice once inundated all of Clements Markham Inlet. During at least one of these undated glaciations, ice flowed unconstrained by the local topography. In contrast, the most recent glaciation involved confluent trunk glaciers, which terminated near the head of the inlet. Beyond this terminus, smaller glaciers entering the sides of the inlet debouched into a glacioisostatically depressed sea (full glacial sea). Retreat from the last glaciation is documented by moraines, kame terraces, and ice-contact deltas.Inside the ice limit at the head of the inlet, sections commonly show that a marine transgression occurred immediately after the retreat of the ice. Conversely, sections outside the last ice limit, along the sides of the inlet, show complex intercalations of marine and glacigenic sediments. These indicate proximal ice-front conditions where small valley glaciers locally contacted the sea.The oldest date on the last ice limit is 9845 BP. After this, slow retreat was in progress, and some glaciers were within 6 km of their current positions by ca. 9700 BP. At the head of the inlet, the mouths of the confluent valleys became ice free by 8000 BP. After 8000 BP, glacial retreat accelerated greatly, so that the entire lowland became ice free within 400 years.Relative sea-level curves from the inlet indicate ice-load changes that confirm this pattern of ice retreat. Outside the last ice limit, the full glacial sea reached 124 m asl by at least 10 000 BP. Emergence from this sea occurred slowly between at least 10 000 and 8000 BP (0.72 m 100 year−1). This period was followed by "normal" rapid postglacial emergence, which decelerated to the present.The marine limit of the full glacial sea rises from 92 m asl, at the outer coast, to 124 m asl near the last ice limit at the head of the inlet. Initial emergence from the full glacial sea occurred simultaneously throughout the inlet. On the proximal side of the last ice limit, the marine limit descends in the up-ice direction and becomes progressively younger. Individual strandlines tilt up in a southwesterly direction towards the central Grant Land Mountains, suggesting a former centre of glacio-isostatic loading in that area.

Recent formations and Their Basal Topography in and around Tokyo Bay, Central Japan

1977 ◽  
Vol 8 (1) ◽  
pp. 32-50 ◽  
Author(s):  
Sohei Kaizuka ◽  
Yo Naruse ◽  
Iware Matsuda
Keyword(s):  
Sea Level ◽  
Early Stage ◽  
Late Quaternary ◽  
Valley Floor ◽  
Tokyo Bay ◽  
Marine Deposits ◽  
Subsurface Geology ◽  
River Terraces ◽  
Type Area ◽  
Geomorphic Surfaces

This paper summarizes the subsurface geology of the recent (both Holocene and latest Pleistocene) formations and the buried topography beneath them in and around Tokyo Bay, the type area of the late Quaternary in Japan. Buried abrasion platforms in the buried topography are classified into upper (ca. 0 to −10 m high) and lower (ca. −20 to −40 m) platforms; upper and lower buried river terraces are also distinguished, and are correlated to the subaerial late Pleistocene terraces of Tc1 and Tc2, respectively. A buried valley system is elucidated, of which the trunk valley floor reaches −70 m in Tokyo and emerges into a flat surface at the shelf edge in the entrance to Tokyo Bay. Approximate dates for these geomorphic surfaces are given. The height of sea level contemporaneous with the buried valley floor (ca. 20,000–15,000 yr BP) is estimated at about −135 m. The recent formations are divided into two members, upper and lower, by a middle sand bed, in addition to the lowest buried valley floor gravel. The lower member, which is composed of brackish to marine deposits of complicated lithofacies, was accumulated in narrow drowned valleys during the early stage of the Yurakucho (Flandrian) transgression. The middle sand bed is the foreset bed of deltas, which was formed during a slight regression between ca. 11,000 and 10,000 yr BP. The upper member, which consists mainly of widespread homogeneous marine clay and deltaic sand, was accumulated in a wide bay and its embayments during the late stage of the Yurakucho transgression and the following stage of a relatively stable sea level.

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