scholarly journals Late Holocene landscape change history related to the Alpine Fault determined from drowned forests in Lake Poerua, Westland, New Zealand

2012 ◽  
Vol 12 (6) ◽  
pp. 2051-2064 ◽  
Author(s):  
R. M. Langridge ◽  
R. Basili ◽  
L. Basher ◽  
A. P. Wells
Keyword(s):  
Lake Level ◽  
Late Holocene ◽  
Alluvial Fan ◽  
Time Of Death ◽  
Fault Rupture ◽  
Radiocarbon Dates ◽  
Living Tree ◽  
Alpine Fault ◽  
History Of ◽  
Lowland Forests

Abstract. Lake Poerua is a small, shallow lake that abuts the scarp of the Alpine Fault on the West Coast of New Zealand's South Island. Radiocarbon dates from drowned podocarp trees on the lake floor, a sediment core from a rangefront alluvial fan, and living tree ring ages have been used to deduce the late Holocene history of the lake. Remnant drowned stumps of kahikatea (Dacrycarpus dacrydioides) at 1.7–1.9 m water depth yield a preferred time-of-death age at 1766–1807 AD, while a dryland podocarp and kahikatea stumps at 2.4–2.6 m yield preferred time-of-death ages of ca. 1459–1626 AD. These age ranges are matched to, but offset from, the timings of Alpine Fault rupture events at ca. 1717 AD, and either ca. 1615 or 1430 AD. Alluvial fan detritus dated from a core into the toe of a rangefront alluvial fan, at an equivalent depth to the maximum depth of the modern lake (6.7 m), yields a calibrated age of AD 1223–1413. This age is similar to the timing of an earlier Alpine Fault rupture event at ca. 1230 AD ± 50 yr. Kahikatea trees growing on rangefront fans give ages of up to 270 yr, which is consistent with alluvial fan aggradation following the 1717 AD earthquake. The elevation levels of the lake and fan imply a causal and chronological link between lake-level rise and Alpine Fault rupture. The results of this study suggest that the growth of large, coalescing alluvial fans (Dry and Evans Creek fans) originating from landslides within the rangefront of the Alpine Fault and the rise in the level of Lake Poerua may occur within a decade or so of large Alpine Fault earthquakes that rupture adjacent to this area. These rises have in turn drowned lowland forests that fringed the lake. Radiocarbon chronologies built using OxCal show that a series of massive landscape changes beginning with fault rupture, followed by landsliding, fan sedimentation and lake expansion. However, drowned Kahikatea trees may be poor candidates for intimately dating these events, as they may be able to tolerate water for several decades after metre-scale lake level rises have occurred.

Holocene evolution of the Assiniboine River paleochannels and Portage la Prairie alluvial fan

1989 ◽  
Vol 26 (9) ◽  
pp. 1834-1841 ◽  
Author(s):  
W. F. Rannie ◽  
L. H. Thorleifson ◽  
J. T. Teller
Keyword(s):  
Alluvial Fan ◽  
Red River ◽  
Lake Agassiz ◽  
Radiocarbon Dates ◽  
The Holocene ◽  
Sediment Loads ◽  
History Of ◽  
Western Side

The Portage la Prairie alluvial fan was constructed by numerous successive paleochannels of the Assiniboine River along the western side of the Lake Agassiz basin as the level of the lake rapidly declined beginning 9500 years ago. The history of the paleochannels during the first several thousand years is not known. Paleochannel morphologies and cross-cutting relations, soil maturity, and radiocarbon dates, however, indicate that by 6000–7000 years ago flow was northward into Lake Manitoba. This direction was maintained until about 3000 years ago, when avulsion redirected the Assiniboine eastward to the Red River near Winnipeg. The morphologies of the paleochannels suggest that channel-forming discharges and sediment loads of the ancestral rivers have not differed significantly from the modern values despite palynological evidence that the climate was warmer and drier during much of the Holocene.

scholarly journals Late Holocene Rupture History of the Alpine Fault in South Westland, New Zealand

2012 ◽  
Vol 102 (2) ◽  
pp. 620-638 ◽  
Author(s):  
K. Berryman ◽  
A. Cooper ◽  
R. Norris ◽  
P. Villamor ◽  
R. Sutherland ◽  
...  
Keyword(s):  
New Zealand ◽  
Late Holocene ◽  
Alpine Fault ◽  
History Of

scholarly journals Fluvial Sedimentology and Paleoecology of Holocene Alluvial Deposits, Red River, Manitoba

2007 ◽  
Vol 47 (2) ◽  
pp. 193-210 ◽  
Author(s):  
Erik Nielsen ◽  
W. Brian McKillop ◽  
Glen G. Conley
Keyword(s):  
Late Holocene ◽  
Red River ◽  
Present Position ◽  
Lake Agassiz ◽  
Alluvial Deposits ◽  
Radiocarbon Dates ◽  
The North ◽  
Mollusc Species ◽  
History Of ◽  
Overbank Sedimentation

ABSTRACT Stratigraphie and paleoecological analyses at five sections, together with age determinations based on 19 previously published and 21 new radiocarbon dates, provide a detailed late Holocene history of the Red River, Manitoba. Ecological information, such as age frequency analysis, relative abundance, diversity and association of species was drawn from 19 mollusc species. These data indicate that the Red and Assiniboine rivers cut the valleys they occupy today within a thousand years of the regression of Lake Agassiz. In the south, up to 14 m of alluvium has accumulated during the last 7000 years. A decrease in the sedimentation rate at 1400 BP is coincident with the shift in the position of the Assiniboine from the valley of the La Salle River to its present position. Overbank sedimentation did not start in the northern part of the area until ca. 5200 BP. Initial rapid sedimentation rates in this area are attributed to increased precipitation and a brief eastward excursion of the Assiniboine River into the Red. In spite of increased precipitation, flood frequencies remained low in the north until 1400 BP. Increased overbank sedimentation after 1400 BP is attributed to the northward shift in the position ot the Assiniboine.

Between the mountains and the sea: Late Holocene Caspian Sea level fluctuations and vegetation history of the lowland forests of northern Iran

2016 ◽  
Vol 408 ◽  
pp. 52-64 ◽  
Author(s):  
Elias Ramezani ◽  
Almut Mrotzek ◽  
Mohammad Reza Marvie Mohadjer ◽  
Ata Abdollahi Kakroodi ◽  
Salomon B. Kroonenberg ◽  
...  
Keyword(s):  
Sea Level ◽  
Caspian Sea ◽  
Late Holocene ◽  
Vegetation History ◽  
Northern Iran ◽  
Sea Level Fluctuations ◽  
History Of ◽  
Lowland Forests

scholarly journals Stochastic alluvial fan and terrace formation triggered by a high-magnitude Holocene landslide in the Klados Gorge, Crete

2021 ◽  
Author(s):  
Elena T. Bruni ◽  
Richard F. Ott ◽  
Vincenzo Picotti ◽  
Negar Haghipour ◽  
Karl W. Wegmann ◽  
...  
Keyword(s):  
Late Holocene ◽  
Alluvial Fan ◽  
Tectonic Activity ◽  
Climate Variations ◽  
Alluvial Deposits ◽  
Small Catchment ◽  
Radiocarbon Dates ◽  
Quaternary Climate ◽  
Stochastic Events

Abstract. Alluvial fan and terrace formation is traditionally interpreted as related to Quaternary climate oscillations under the backdrop of slow and steady tectonic activity. However, several recent studies challenge this conventional wisdom, showing that such landforms can evolve rapidly as a geomorphic system responds to catastrophic and stochastic events, like large magnitude mass-wasting. Here, we contribute to this topic through a detailed field and geochronological investigation of alluvial sequences in the Klados catchment in southwestern Crete, Greece. The Klados River catchment is characterised by well-preserved, alluvial terraces and a set of fans at the river mouth, which do not seem to fit the sediment capacity of a small catchment with a drainage area of ~ 11.5 km2. Previous studies interpreted the formation of the deposits and their development to be of Pleistocene age and controlled by climate variations and the region's long-term tectonic activity. We find that the > 20 m thick intermediate fan buries a paleoshoreline uplifted in AD 365 placing the depositional age of this unit firmly into the Late Holocene. This is supported by seven new radiocarbon dates that infer mid to late Holocene ages for the entire fan and terrace sequence. As sediment source, we identify a landslide scar at the head of the catchment. We document landslide deposits 100 m above the modern stream and utilise landslide runout modelling to reconstruct landslide volumes and validate our hypothesis. We find that a landslide volume of 0.0908 km2 matches the observed distribution of landslide deposits and the landslide scar dimensions. We hypothesise that subsequent aggradation and incision cycles of the alluvial deposits are not linked to long-term tectonic uplift and climate variations but rather stochastic events such as mobilisation of sediment in large earthquakes, storm events, or blockage in the valley's narrow reaches. The Klados case study represents a model-environment for how stochastically-driven events can mimic climate-induced sedimentary archives, and how catchments can become ultrasensitive to external perturbations after catastrophic events.

Radiocarbon Reservoir Effect and the Timing of the Late-Glacial/Early Holocene Humid Phase in the Atacama Desert (Northern Chile)

1999 ◽  
Vol 52 (2) ◽  
pp. 143-153 ◽  
Author(s):  
Mebus A. Geyh ◽  
Martin Grosjean ◽  
Lautaro Núñez ◽  
Ulrich Schotterer
Keyword(s):  
Lake Level ◽  
Atacama Desert ◽  
Late Glacial ◽  
Early Holocene ◽  
Vegetation Changes ◽  
Northern Chile ◽  
Lake Levels ◽  
Human Occupation ◽  
Radiocarbon Dates ◽  
History Of

We revise substantially the regional chronology of lake-level fluctuations from the late-glacial/early Holocene humid phase along a high altitude transect (3500 to 4500 m) between 18°S and 28°S in the Southwestern Altiplano of Northern Chile. Radiocarbon dates and 210Pb profiles for limnic and terrestrial materials allow us to estimate and justify reservoir correction values for conventional 14C dates. Our chronology suggests that the latest Pleistocene/early Holocene humid phase started between 13,000 and 12,000 14C yr B.P., and that maximum lake levels were reached between 10,800 and 9200 14C yr B.P. This is significantly younger than what has been established so far for the Titicaca–Uyuni Basin in Bolivia. The paleolakes disappeared sometime between 8400 and 8000 14C yr B.P. Our revised chronology agrees with the regional history of human occupation, and is broadly synchronous with vegetation changes in subtropical continental South America, and with the onset of wetland expansion in the northern hemisphere tropics.

Lake level and paleoenvironmental history of Lake Tanganyika, Africa, as inferred from late Holocene and modern stromatolites

1997 ◽  
Vol 109 (4) ◽  
pp. 444-460 ◽  
Author(s):  
Andrew S. Cohen ◽  
Michael R. Talbot ◽  
Stanley M. Awramik ◽  
David L. Dettman ◽  
Paul Abell
Keyword(s):  
Lake Level ◽  
Late Holocene ◽  
Lake Tanganyika ◽  
History Of

scholarly journals Stochastic alluvial fan and terrace formation triggered by a high-magnitude Holocene landslide in the Klados Gorge, Crete

2021 ◽  
Vol 9 (4) ◽  
pp. 771-793
Author(s):  
Elena T. Bruni ◽  
Richard F. Ott ◽  
Vincenzo Picotti ◽  
Negar Haghipour ◽  
Karl W. Wegmann ◽  
...  
Keyword(s):  
Late Holocene ◽  
Alluvial Fan ◽  
Tectonic Activity ◽  
System Response ◽  
Alluvial Deposits ◽  
Radiocarbon Dates ◽  
High Magnitude ◽  
Stochastic Events ◽  
Landslide Deposit

Abstract. Alluvial fan and terrace formation is traditionally interpreted as a fluvial system response to Quaternary climate oscillations under the backdrop of slow and steady tectonic activity. However, several recent studies challenge this conventional wisdom, showing that such landforms can evolve rapidly as a geomorphic system responds to catastrophic and stochastic events, like large-magnitude mass wasting. Here, we contribute to this topic through a detailed field, geochronological, and numerical modelling investigation of thick (>50 m) alluvial sequences in the Klados catchment in southwestern Crete, Greece. The Klados River catchment lies in a Mediterranean climate, is largely floored by carbonate bedrock, and is characterised by well-preserved alluvial terraces and inset fans at the river mouth that exceed the volumes of alluvial deposits in neighbouring catchments of similar size. Previous studies interpreted the genesis and evolution of these deposits to result from a combination of Pleistocene sea-level variation and the region's long-term tectonic activity. We show that the >20 m thick lower fan unit, previously thought to be late Pleistocene in age, unconformably buries a paleoshoreline uplifted in the first centuries CE, placing the depositional age of this unit firmly in the late Holocene. The depositional timing is supported by seven new radiocarbon dates that indicate middle to late Holocene ages for the entire fan and terrace sequence. Furthermore, we report new evidence of a previously unidentified valley-filling landslide deposit that is locally 100 m above the modern stream elevation, and based on cross-cutting relationships, it predates the alluvial sequence. Observations indicate the highly erodible landslide deposit as the source of the alluvial fill sediment. We identify the likely landslide detachment area as a large rockfall scar at the steepened head of the catchment. A landslide volume of 9.08×107 m3 is estimated based on volume reconstructions of the mapped landslide deposit and the inferred scar location. We utilise landslide runout modelling to validate the hypothesis that a high-magnitude rockfall would pulverise and send material downstream, filling the valley up to ∼100 m. This partial liquefaction is required for the rockfall to form a landslide body of the extent observed in the valley and is consistent with the sedimentological characteristics of the landslide deposit. Based on the new age control and the identification of the landslide deposit, we hypothesise that the rapid post-landslide aggradation and incision cycles of the alluvial deposits are not linked to long-term tectonic uplift or climate variations but rather stochastic events such as mobilisation of sediment in large earthquakes, storm events, or ephemeral blockage in the valley's narrow reaches. The Klados case study represents a model environment for how stochastically driven events can mimic climate-induced sedimentary archives and lead to deposition of thick alluvial sequences within hundreds to thousands of years, and it illustrates the ultrasensitivity of mountainous catchments to external perturbations after catastrophic events.

Holocene sedimentary architecture and paleoclimate variability at Mono Lake, California

2019 ◽  
Author(s):  
S.R.H. Zimmerman ◽  
S.R. Hemming ◽  
S.W. Starratt
Keyword(s):  
Sierra Nevada ◽  
Lake Level ◽  
Late Holocene ◽  
Mono Lake ◽  
Ice Age ◽  
Historical Period ◽  
Radiocarbon Dates ◽  
The Core ◽  
Sedimentary Architecture ◽  
Lake Floor

ABSTRACT Mono Lake occupies an internally drained basin on the eastern flank of the Sierra Nevada, and it is sensitive to climatic changes affecting precipitation in the mountains (largely delivered in the form of snowpack). Efforts to recover cores from the lake have been impeded by coarse tephra erupted from the Mono Craters, and by disruption of the lake floor due to the uplift of Paoha Island ~300 yr ago. In this study, we describe the stratigraphy of cores from three recent campaigns, in 2007, 2009, and 2010, and the extents and depths of the tephras and disturbed sediments. In the most successful of these cores, BINGO-MONO10-4A-1N (BINGO/10-4A, 2.8 m water depth), we used core stratigraphy, geochemistry, radiocarbon dates, and tephrostratigraphy to show that the core records nearly all of the Holocene in varying proportions of detrital, volcanic, and authigenic sediment. Both the South Mono tephra of ca. 1350 cal yr B.P. (calibrated years before A.D. 1950) and the 600-yr-old North Mono–Inyo tephra are present in the BINGO/10-4A core, as are several older, as-yet-unidentified tephras. Laminated muds are inferred to indicate a relatively deep lake (³10 m over the core site) during the Early Holocene, similar to many records across the region during that period. The Middle and Late Holocene units are more coarsely bedded, and coarser grain size and greater and more variable amounts of authigenic carbonate detritus in this interval are taken to suggest lower lake levels, possibly due to lower effective wetness. A very low lake level, likely related to extreme drought, is inferred to have occurred sometime between 3500 and 2100 cal yr B.P. This interval likely corresponds to the previously documented Marina Low Stand and the regional Late Holocene Dry Period. The BINGO/10-4A core does not preserve a complete record of the period encompassing the Medieval Climate Anomaly, the Little Ice Age, and the historical period, probably due to erosion because of its nearshore position.

Holocene Paleoseismology of the Steamboat Mountain Site: Evidence for Full-Length Rupture of the Teton Fault, Wyoming

2020 ◽  
Author(s):  
Christopher B. DuRoss ◽  
Mark S. Zellman ◽  
Glenn D. Thackray ◽  
Richard W. Briggs ◽  
Ryan D. Gold ◽  
...  
Keyword(s):  
Normal Fault ◽  
Vertical Displacement ◽  
Alluvial Fan ◽  
Full Length ◽  
Fault Rupture ◽  
Partial Length ◽  
Mountain Site ◽  
Vertical Displacements ◽  
History Of ◽  
Lateral Extent

ABSTRACT The 72-km-long Teton fault in northwestern Wyoming is an ideal candidate for reconstructing the lateral extent of surface-rupturing earthquakes and testing models of normal-fault segmentation. To explore the history of earthquakes on the northern Teton fault, we hand-excavated two trenches at the Steamboat Mountain site, where the east-dipping Teton fault has vertically displaced west-sloping alluvial-fan surfaces. The trenches exposed glaciofluvial, alluvial-fan, and scarp-derived colluvial sediments and stratigraphic and structural evidence of two surface-rupturing earthquakes (SM1 and SM2). A Bayesian geochronologic model for the site includes three optically stimulated luminescence ages (∼12–17  ka) for the glaciofluvial units and 16 radiocarbon ages (∼1.2–8.6  ka) for the alluvial-fan and colluvial units and constrains SM1 and SM2 to 5.5±0.2  ka, 1σ (5.2–5.9 ka, 95%) and 9.7±0.9  ka, 1σ (8.5–11.5 ka, 95%), respectively. Structural, stratigraphic, and geomorphic relations yield vertical displacements for SM1 (2.0±0.6  m, 1σ) and SM2 (2.0±1.0  m, 1σ). The Steamboat Mountain paleoseismic chronology overlaps temporally with earthquakes interpreted from previous terrestrial and lacustrine paleoseismic data along the fault. Integrating these data, we infer that the youngest Teton fault rupture occurred at ∼5.3  ka, generated 1.7±1.0  m, 1σ of vertical displacement along 51–70 km of the fault, and had a moment magnitude (Mw) of ∼7.0–7.2. This rupture was apparently unimpeded by structural complexities along the Teton fault. The integrated chronology permits a previous full-length rupture at ∼10  ka and possible partial ruptures of the fault at ∼8–9  ka. To reconcile conflicting terrestrial and lacustrine paleoseismic data, we propose a hypothesis of alternating full- and partial-length ruptures of the Teton fault, including Mw∼6.5–7.2 earthquakes every ∼1.2  ky. Additional paleoseismic data for the northern and central sections of the fault would serve to test this bimodal rupture hypothesis.

Sign in / Sign up

Export Citation Format

Share Document