Basal Channel Research Articles

Antarctic ice-shelf meltwater outflows in satellite radar imagery: ground-truthing and basal channel observations

Abstract Ice shelves regulate the flow of the Antarctic ice sheet toward the ocean and its contribution to sea-level rise. Accurately monitoring the basal and surface melting of ice shelves is therefore essential for predicting the ice sheet's response to climatic warming. In this study, we utilize Sentinel-1A synthetic aperture radar satellite imagery combined with shipboard measurements of water temperature and salinity to investigate the presence of surficial meltwater plumes along the Antarctic coastline. Our approach reveals a strong correlation between areas of pronounced low radar backscatter extending from ice shelves and significant decreases in water temperature and salinity, suggesting meltwater-enriched ocean waters. We propose that the low radar backscatter signature of meltwater outflows is caused by stable stratification of the upper water column, driven by density contrasts from buoyant, low-salinity meltwater and surface current shear that reduce Bragg scattering waves. The resulting smooth water surfaces were observed adjacent to the surface expression of deep basal channels, documented in a helicopter survey along part of the Bellingshausen Sea ice edge. We present high-temporal resolution satellite radar as a tool for identifying meltwater release from beneath ice shelves, capable of all-weather, day-and-night imaging.

Home blood pressure-lowering effect of esaxerenone versus trichlormethiazide for uncontrolled hypertension: a predefined subanalysis of the EXCITE-HT randomized controlled trial by basal calcium channel blocker versus angiotensin receptor blocker.

This prespecified subanalysis of the multicenter, randomized, open-label, parallel-group EXCITE-HT study aimed to examine the non-inferiority of esaxerenone to trichlormethiazide as a second-line antihypertensive agent according to the basal antihypertensive agent used (angiotensin receptor blocker [ARB] or calcium channel blocker [CCB]). The primary endpoint, change in morning home systolic/diastolic blood pressure (SBP/DBP) from baseline to end of treatment was similar between the two groups (intergroup difference in least squares mean change [95% confidence interval]: -1.3 [-3.8, 1.3]/-0.2 [-1.6, 1.3] mmHg for ARB; -2.7 [-4.2, -1.2]/-0.8 [-1.7, 0.1] mmHg for CCB). The respective incidences of serum potassium levels <3.5 mEq/L and ≥5.5 mEq/L in the ARB subgroup were 3.4% and 4.2% for esaxerenone and 7.9% and 0% for trichlormethiazide; in the CCB subgroup, they were 2.8% and 0.6% for esaxerenone and 13.9% and 1.2% for trichlormethiazide, respectively. The incidence of uric acid level ≥7.0 mg/dL was numerically higher in the trichlormethiazide group than the esaxerenone group in both the ARB and CCB subgroups. The non-inferiority of esaxerenone to trichlormethiazide in lowering morning home BP was demonstrated regardless of whether the basal antihypertensive agent was an ARB or CCB. Esaxerenone with a CCB showed superiority to trichlormethiazide in lowering SBP, without any new safety concerns. Serum potassium levels tended to be higher when esaxerenone was combined with an ARB than with a CCB, but this can be mitigated if administered according to the package insert. A subgroup analysis of the EXCITE-HT study according to basal antihypertensive agent demonstrated the non-inferiority of esaxerenone to trichlormethiazide in lowering morning home BP regardless irrespective of the basal antihypertensive agent. Esaxerenone with a CCB showed superiority to trichlormethiazide in lowering SBP, without any new safety concerns.

Mechanism and controlling factors of mass transport complexes migration: A case study of the mass transport complexes in the taranaki deep water basin, New Zealand

Mass transport Complexes (MTCs) form significant sediment accumulations in continental slopes, hold key insights for natural hazard prediction and offshore oil exploration. This paper uses high-definition 3D seismic data to reconstruct the seismic geomorphology and sedimentary dynamics of MTCs, meticulously exploring the depositional systems of the Tanaraki Basin, New Zealand. It deciphers by kinematic notation, seismic faciess, quantifies megaclast morphological characteristics, in conjunction with the basal slope and channel structure development as the migration or kinematics of MTCs. Five seismic facies categories and dynamic traits—compression ridges, thrust faults, slides, grooves and slope terraces are distinguished in MTCs. Based on attributes maps and geomorphological interpretations, MTCs is segmented into four zones, showing combined effects of levée, basal slopes, and megaclast clusters on its migration. Lithological and topographical variations along these features modulate erosion properties and MTCs mobility, with base height shifts guiding local migration trajectories. The results of megaclast parameters in Zones 1 and 3 tune our understanding of stress patterns and directionality shifts, highlighting the complex dynamics at play. Notably, the differential motion triggered by levees instigates longitudinal shear zones. At critical migration disparities, MTCs fracture at these weak points, discharging pore pressure and filling fractures with fines, birthing “promontory” formations marked by low-amplitude fills. This work, therefore, establishes a groundbreaking migratory model that synthesizes the impacts of levees height, rock type variability, and megaclasts accumulation intensity, depicting a fragmented migration pattern. This study not only enriches our grasp of MTCs behavior in deep-water contexts but also furnishes a robust scientific foundation and predictive tool for gauging the hazards that MTCs may pose to underwater structures, thus carrying substantial theoretical and applied significance.

Ice shelf basal channel shape determines channelized ice-ocean interactions

Growing evidence has confirmed the critical role played by basal channels beneath Antarctic ice shelves in both ice shelf stability and freshwater input to the surrounding ocean. Here we show, using a 3D ice shelf-ocean boundary current model, that deeper basal channels can lead to a significant amplification in channelized basal melting, meltwater channeling, and warming and salinization of the channel flow. All of these channelized quantities are also modulated by channel width, with the level of modulation determined by channel height. The explicit quantification of channelized basal melting and the meltwater transport in terms of channel cross-sectional shape is potentially beneficial for the evaluation of ice shelf mass balance and meltwater contribution to the nearshore oceanography. Complicated topographically controlled circulations are revealed to be responsible for the unique thermohaline structure inside deep channels. Our study emphasizes the need for improvement in observations of evolving basal channels and the hydrography inside them, as well as adjacent to the ice front where channelized meltwater emerges.

Submarine‐channel meandering reset by landslide filling, Taranaki Basin, New Zealand

AbstractLandslides are among the largest mass movements on Earth. As such, the deposits of landslides, also known as mass‐transport deposits, are significant architectural elements of continental margins, especially those receiving sediment from large deltas. Landslide dams have been shown to alter the courses of rivers and submarine channels. However, there are fewer examples of landslides completely filling submarine channels and examples of the subsequent stratigraphic evolution. A three‐dimensional seismic‐reflection dataset (&lt;90 Hz) from the deep‐water (&gt;1500 m) Taranaki Basin, offshore the North Island of New Zealand, was used to explore the response of a sequence of channel deposits to landslide filling. The basal channel system initially meandered like a river, with successive channel positions in close proximity, as it aggraded &gt;250 ms two‐way travel time. This systematic, organised evolution is governed by the memory of early channel evolution, which sets the sea floor geomorphology that guides channel‐forming turbidity currents. Later, a channel approximately twice as wide as underlying channels cut off a number of channel bends, probably as a result of an increase in the discharge of channel‐forming turbidity currents. This last channel was filled with submarine landslides, which transported and deposited sediment as debris flows based on the presence of blocks within a matrix comprising chaotic, lower amplitude seismic facies. These debris‐flow deposits smoothed over the sea floor, effectively wiping the memory of channel evolution. As a result, the subsequent channel pattern bears no resemblance to the basal system. Submarine‐channel resetting by landslide filling is common in settings with frequent catastrophic basin‐margin collapses, like offshore New Zealand.

Cholesterol regulation of mechanosensitive ion channels.

The purpose of this review is to evaluate the role of cholesterol in regulating mechanosensitive ion channels. Ion channels discussed in this review are sensitive to two types of mechanical signals, fluid shear stress and/or membrane stretch. Cholesterol regulates the channels primarily in two ways: 1) indirectly through localizing the channels into cholesterol-rich membrane domains where they interact with accessory proteins and/or 2) direct binding of cholesterol to the channel at specified putative binding sites. Cholesterol may also regulate channel function via changes of the biophysical properties of the membrane bilayer. Changes in cholesterol affect both mechanosensitivity and basal channel function. We focus on four mechanosensitive ion channels in this review Piezo, Kir2, TRPV4, and VRAC channels. Piezo channels were shown to be regulated by auxiliary proteins that enhance channel function in high cholesterol domains. The direct binding mechanism was shown in Kir2.1 and TRPV4 where cholesterol inhibits channel function. Finally, cholesterol regulation of VRAC was attributed to changes in the physical properties of lipid bilayer. Additional studies should be performed to determine the physiological implications of these sterol effects in complex cellular environments.

The great calving in 2017 did not have a significant impact on the Larsen C Ice Shelf in the short term

ABSTRACT The stability of the Larsen C Ice Shelf (LIS) has been widely studied due to its surface lowering, calving, and warming. In this study, we combined multisource remote-sensing data, calculated the long-term series of surface elevation above basal channels and basal melt rate, and analyzed the dynamic changes in the LIS before and after calving in 2017. We found that the basal channels were mainly concentrated in the southern LIS, and the basal melt rate was higher in the south. The Weddell Sea warm water mass entered the bottom of the LIS through the sea trough and promoted basal melting. There was an abnormal basal channel where changes in sea ice concentrations caused by wind-driven currents led to abnormal development. We did not observe significant changes in ice thickness, ice velocity and strain rate in the short term before and after the great calving in 2017. However, the basal melt rate was mainly influenced by the sea ice extent in front of the LIS from 2010 to 2020. Changes in the sea ice extent indirectly altered the proportion of High Salinity Shelf Water (HSSW) entering the ice shelf bottom water mass, which in turn promoted (or inhibited) basal melting of the LIS. In other words, we found no evidence for any dynamic changes in the LIS before and after the great calving in 2017. Since the calving area was within the Passive Shelf Ice (PSI), we have also provided additional evidence for the existence of the PSI. In addition, we speculate that the impact of calving on the LIS will not be visible in the short term, so we need to continuously observe the subsequent dynamic changes in the LIS.

Establishment of Human Bone Marrow-on-Chip As a Preclinical Model to Evaluate Drug-Induced Toxicities and Myelofibrosis Patient-Specific Pathophysiology

Hematopoiesis takes place in the bone marrow (BM) and is supported by a complex cellular and molecular network in the BM microenvironment. The inaccessibility of living human BM hampers the study of its pathophysiology under stress induced by drugs, radiation, or genetic mutations. Commonly used models of the human BM microenvironment rely on mouse models and 2D or 3D static tissue cultures. Although existing in vitro hematopoiesis models have led to advances in the field, they fail to recapitulate the biology of cellular interactions, cell extrinsic factors, and complex functions of living human BM hematopoiesis. This has also limited our understanding of human BM biology and the influence of BM niche cells in BM defects in diseases such as myeloproliferative neoplasms (MPNs) and leukemias. Consequently, there is an unmet need to develop a preclinical human BM hematopoiesis model that supports growth and differentiation of multilineage hematopoietic stem cells to enable evaluation of investigational compounds for myeloerythroid toxicity and efficacy. Microphysiologic systems (MPS), such as organ-on-chips, emulate the complex interplay between intrinsic and extrinsic cell factors in the BM microenvironment, the 3D tissue architecture, and are more clinically relevant compared with static co-culture approaches (PMID: 31988457; PMID: 37359774). Here we present the development of a human BM-on-chip MPS model to recapitulate both healthy and MPN disease and evaluate the alterations in the BM niche environment. We utilized a commercially available organ-on-chip microfluidic platform (Emulate, Boston, MA) to develop a living human BM with a functional hematopoietic niche in vitro by perfusion with culture medium. This fluidic-controlled modular chip comprises an osteogenic apical channel separated from a vascular basal channel by a semiporous membrane, which allows for media perfusion, cellular crosstalk, and intercellular signaling. The osteogenic apical channel is filled with a fibrin gel that allows the co-culture of all critical cells of the BM niche, including osteoblasts, endothelial cells, mesenchymal stem cells, hematopoietic stem and progenitor cells. The parallel basal channel is lined by human vascular endothelium and is perfused with culture medium optimized to allow survival and development of functional hematopoietic lineage niche cell populations. This unidirectional fluidic MPS model allows for collection of cell effluents for evaluation of cell-extrinsic factors such as cytokines, extracellular vesicles, and metabolites. The modular and accessible nature of this system provides an advantage to investigate the effects of the microenvironment and drug candidates individually on the osteogenic and vascular compartments. This human BM-on-chip has been tested with cells from several healthy and myelofibrosis donors. Utilizing imaging, flow cytometry, cytokine profiling, and transcriptomics, we demonstrate that the vascularized human BM-on-chip recapitulates the living human hematopoietic niche, with BM relevant cytokine levels, retains hematopoietic stem and progenitor cells in in vivo-like proportions for over 3 weeks in culture, allows for the differentiation of BM niche lineage cell populations similar to human BM aspirate, and captures human donor variabilities. We also show that BM-on-chips derived from MPN patients recapitulate the hematopoietic defects to understand the biology and disease response in myelofibrosis. Our robust experimental workflow and bioinformatics platform will be utilized to evaluate candidate compounds for BM myelotoxicities, drug mechanisms of action, and biomarkers in a multifactorial manner to support preclinical programs. This biomimetic platform offers a new approach for analysis of drug responses and toxicities in BM as well as for study of hematopoiesis and hematologic diseases such as myelofibrosis.

Basal Channel System and Polynya Effect on a Regional Air‐Ice‐Ocean‐Biology Environment System in the Prydz Bay, East Antarctica

AbstractThe interaction of air‐ice‐ocean‐biology plays a key role in the global environment and sea‐level changes. The basal channel at the bottom of the Amery Ice Shelf (AIS) and the Mackenzie polynya are the intense sites for the interaction of air‐ice‐ocean‐biology in the Prydz Bay. In this study, the spatio‐temporal distribution characteristics of the complex basal channel system from the 1990s to 2019 are discovered and analyzed. The shapes of the channels are inverted‐V in the deep parts, gradually becoming inverted‐U as it develops in accordance with the direction of erosion. The deepest part of the basal channel system is over 800 m resulting from the meltwater plumes at the southernmost grounding zone. The linear and thinner channel region is the weakest and most sensitive part under ocean forcing leading to instability of the AIS (e.g., longitudinal fractures and calving). Conductivity‐temperature‐depth data are used to confirm the paths and shapes of the warm and cold water in the interaction. Channels can be divided into warm and cold‐water channels based on filled water masses. Cold water channels collect the fresh melting water and drain it out. Paths of cold‐water columns from different channels extend to the Mackenzie polynya area, which prevents warm water from entering the west AIS. Meltwater from the channels, warm water, brine produced by the Mackenzie polynya, and marine mammals in the polynya together constitute a complex regional environment system of dynamical air‐ice‐ocean‐biology interactions.

Dehydroepiandrosterone sulfate (DHEAS) is an endogenous Kv7 channel modulator that reduces Kv7/M-current suppression and inflammatory pains.

Neuronal Kv7 voltage-gate potassium channels generate the M-current and regulate neuronal excitability. Here, we report that dehydroepiandrosterone sulfate (DHEAS) is an endogenous Kv7 channel modulator that attenuates Gq-coupled receptor induced M-current suppression. DHEAS reduced muscarinic agonist-induced Kv7-current suppression of either Kv7.1, Kv7.2, Kv7.4 or Kv7.5 homomeric currents and endogenous M-currents in rat sympathetic ganglion neurons. However, DHEAS per se did not alter the voltage-dependence of these Kv7 homomeric channels or the m1 receptor-induced activation of phospholipase C or protein kinase C. DHEAS treated Kv7.2 homomeric currents became resistant to depletion of phosphatidylinositol 4,5-bisphosphate (PIP2) induced by voltage-activated phosphatase, Ci-VSP or eVSP. Our computational models predicted a novel binding site for DHEAS in the cytoplasmic domain of Kv7 subunits. A single point mutation of the predicted key histidine into cysteine in the rat Kv7.2 subunit, rKv7.2(H558C), resulted in a loss of effects of DHEAS on muscarinic Kv7 current suppression. Furthermore, in vivo administration of DHEAS in mice of both sexes reduced late phase pain responses in the formalin paw test. However, it did not have effects on early phase responses in the formalin paw test or responses in the hot plate test. Co-administration of a selective Kv7 inhibitor, XE991, and DHEAS eliminated analgesic effects of DHEAS in late phase responses in the formalin paw test. Collectively, these results suggest that DHEAS attenuates M-current suppression by stabilizing PIP2-Kv7 subunit interaction and can mitigate inflammatory pain.Significance StatementM-current suppression induced by stimulation of Gq-coupled receptors is a form of Kv7 current modulation that can reversibly increase neuronal excitability. This study demonstrates that DHEAS, an endogenous steroid hormone, is a novel Kv7 channel modulator that can attenuate M-current suppression without affecting basal Kv7 channel kinetics. Administration of DHEAS in vivo alleviated inflammatory pain in rodents. These results suggest that the degree of M-current suppression can be dynamically regulated by small molecules. Therefore, this novel form of Kv7 channel regulation holds promising potential as a therapeutic target for sensitized nervous activities such as inflammatory pain.

Rapid Basal Channel Growth Beneath Greenland's Longest Floating Ice Shelf

AbstractNioghalvfjerdsfjorden Glacier (N79) is one of the two main outlets for Greenland's largest ice stream, the Northeast Greenland Ice Stream, and is the more stable of the two, with no calving front retreat expected in the near future. Using a novel surface elevation reconstruction approach combining digital elevation models and laser altimetry, previously undetected local phenomena are identified complicating this assessment. N79 is found to have a complex network of basal channels that were largely stable between 1978 and 2012. Since then, an along‐flow central basal channel has been growing rapidly, likely due to increased runoff and ocean temperatures. This incision threatens to decouple the glacier's northwestern and southeastern halves.

A screening assessment of the impact of sedimentological heterogeneity on CO 2 migration and stratigraphic-baffling potential: Sherwood and Bunter sandstones, UK

Abstract We use a combination of experimental design, sketch-based reservoir modelling and flow diagnostics to rapidly screen the impact of sedimentological heterogeneities that constitute baffles and barriers on CO 2 migration in depleted hydrocarbon reservoirs and saline aquifers of the Sherwood Sandstone Group and Bunter Sandstone Formation, UK. These storage units consist of fluvial sandstones with subordinate aeolian sandstones, floodplain and sabkha heteroliths and lacustrine mudstones. The predominant control on effective horizontal permeability is the lateral continuity of aeolian-sandstone intervals. Effective vertical permeability is controlled by the lateral extent, thickness and abundance of lacustrine-mudstone layers and aeolian-sandstone layers, and the mean lateral extent and mean vertical spacing of carbonate-cemented basal channel lags in fluvial facies-association layers. The baffling effect on CO 2 migration and retention is approximated by the pore volume injected at breakthrough time, which is controlled largely by three heterogeneities, in order of decreasing impact: (1) the lateral continuity of aeolian-sandstone intervals; (2) the lateral extent of lacustrine-mudstone layers; and (3) the thickness and abundance of fluvial-sandstone, aeolian-sandstone, floodplain-and-sabkha-heterolith and lacustrine-mudstone layers. Future effort should be focused on characterizing these three heterogeneities as a precursor for later capillary, dissolution and mineral trapping.

Rapid basal channel growth beneath Greenland's longest floating ice shelf

Rapid basal channel growth beneath Greenland's longest floating ice shelf

Reliable neuromodulation from adaptive control of ion channel expression

Neuromodulation significantly alters neuronal activity and the responsiveness of both neurons and circuits to external inputs by adapting ion channel expression. However, basal ion channel expression is highly variable in neurons, even those with similar functions, which poses the question of how neuromodulation can act reliably. In this paper, we exploit the biophysical structure of neurons and the properties of neuromodulation-induced intracellular signaling to test whether reliable neuromodulation could be achieved by an intracellular control system adapting ion channel expression. The proposed controller has the typical structure of a linear adaptive loop that tunes cellular feedback gains determining neuronal excitability. The feedforward block transforms the neuronal feedback gain reference trajectory into an ion channel expression reference trajectory, while the feedback block, in the form of a simple PI controller, tracks the reference. Both blocks are biologically grounded, yet simple and mathematically tractable. We show that such a simple and biologically grounded control scheme can explain how reliable neuromodulation could be achieved in highly variable neurons. These results illustrate how a complex and highly nonlinear control problem can be tackled by a simple, biologically plausible control loop involving only a few variables.

Extraction and Analysis of the Antarctic Ice Shelf Basal Channel

Extraction and Analysis of the Antarctic Ice Shelf Basal Channel

Melting and Refreezing in an Ice Shelf Basal Channel at the Grounding Line of the Kamb Ice Stream, West Antarctica

AbstractIce shelves buttress ice streams and glaciers, slowing the rate at which they flow into the ocean. When this buttressing is reduced, either through increased melt or calving, the increased discharge of grounded ice upstream contributes to sea level rise. The thickness, strength, and stability of ice shelves can be influenced by channels in the ice base. Here, we focus on a subglacially sourced basal channel which is observed to have melted up to 50% of the ice shelf thickness. The channel extends 6 km upstream of the previously estimated grounding line of the stagnant Kamb Ice Stream. Using a combination of ground–based observations and remote sensing, we find that the channel is growing upstream over time. Over–snow radar surveying images the shape of the channel, constrains a steep inception, and shows that not all of the basal shape is manifest at the surface. Modern surface lowering at the upstream head of the channel is interpreted as a region of focused melt where a subglacial outlet meets the ocean cavity. We estimate this basal melt to be at least 35 m/a in a narrow (200 m × 1.5 km) zone. Downstream from the melt region, repeat phase sensitive radar observations reveal accretion contributing to the growth of a ledge on the true–right side of the channel. We conclude that the channel is likely formed by a retreating subglacial outlet which enhances basal melt episodically.

The role of channelized basal melt in ice-shelf stability: recent progress and future priorities

AbstractBasal channels, which form where buoyant plumes of ocean water and meltwater carve troughs upwards into ice-shelf bases, are widespread on Antarctic ice shelves. The formation of these features modulates ice-shelf basal melt by influencing the flow of buoyant plumes, and influences structural stability through concentration of strain and interactions with fractures. Because of these effects, and because basal channels can change rapidly, on timescales similar to those of ice-shelf evolution, constraining the impacts of basal channels on ice shelves is necessary for predicting future ice-shelf destabilization and retreat. We suggest that future research priorities should include constraining patterns and rates of basal channel change, determining mechanisms and detailed patterns of basal melt, and quantifying the influence that channel-related fractures have on ice-shelf stability.

Temporal and spatial changes of the basal channel of the Getz Ice Shelf in Antarctica derived from multi-source data

Temporal and spatial changes of the basal channel of the Getz Ice Shelf in Antarctica derived from multi-source data

Molecular determinants of pH sensing in the proton-activated chloride channel

In response to acidic pH, the widely expressed proton-activated chloride (PAC) channel opens and conducts anions across cellular membranes. By doing so, PAC plays an important role in both cellular physiology (endosome acidification) and diseases associated with tissue acidosis (acid-induced cell death). Despite the available structural information, how proton binding in the extracellular domain (ECD) leads to PAC channel opening remains largely unknown. Here, through comprehensive mutagenesis and electrophysiological studies, we identified several critical titratable residues, including two histidine residues (H130 and H131) and an aspartic acid residue (D269) at the distal end of the ECD, together with the previously characterized H98 at the transmembrane domain-ECD interface, as potential pH sensors for human PAC. Mutations of these residues resulted in significant changes in pH sensitivity. Some combined mutants also exhibited large basal PAC channel activities at neutral pH. By combining molecular dynamics simulations with structural and functional analysis, we further found that the β12 strand at the intersubunit interface and the associated "joint region" connecting the upper and lower ECDs allosterically regulate the proton-dependent PAC activation. Our studies suggest a distinct pH-sensing and gating mechanism of this new family of ion channels sensitive to acidic environment.

Chronology constraints on the complex sedimentary stratigraphy of the paleo-Yangtze incised valley in China

Numerous studies have documented the sedimentary sequences of the Yangtze Delta in response to relative sea-level changes since the Last Glacial Maximum (LGM). However, the pre-LGM sedimentary history of the paleo-Yangtze Delta remains unknown, especially for the formation timing of the basal fluvial sedimentary succession in the paleo-Yangtze incised valley. Here, based on luminescence dating techniques, the sedimentary stratigraphy of three sediment cores (YD016, YD014 and YD006) were constrained and the sedimentary successions were analyzed. Combining with previously published sedimentary sequences, we infer spatiotemporal variation of the stratigraphic architectures over the Yangtze Delta through the time spanning from the late Pleistocene to the Holocene (∼50–0 ka). Our reconstruction for the paleogeography and environmental evolution of the paleo-Yangtze incised valley showed that the basal fluvial channel belts in the paleovalley associated with coeval laterally extensive paleosol-bearing stratigraphy at the interfluves occurred in the transition between marine isotope stage (MIS) 3 and MIS 2; the overlying sedimentary successions are characterized by the post-glacial floodplain deposits formed between 19 and 12 ka, and estuary to shallow marine deposits during early Holocene (11–8 ka); and then the upper most is the Yangtze Delta depositional systems dated to mid-to-late Holocene (since ∼8 ka). Correlations of the chronostratigraphy of sediment cores over the cross-sections in this region suggest that a superimposed compound fluvial channel complex has probably characterized the paleo-Yangtze incised valley systems since MIS 3. Apart from the post-LGM infilling of the LGM incised valley, the basal MIS 3 fluvial deposits might represent the earlier infilling over another incised valley, which might be formed during MIS 4 although our cores have not reached yet. Such hierarchical incised valley systems in the paleo-Yangtze Delta were likely related to the late Quaternary sea-level changes. In addition, the relict inherited topography since the last glacial period could have played an important role in the stacking patterns of the paleo-Yangtze incised valleys.