Chinese Journal of Oceanology and Limnology   2015, Vol. 33 Issue(3): 748-763     PDF
Shanghai University

Article Information

WANG Xin1,2, SHI Xuefa3, WANG Guoqing4, QIAO Shuqing3, WANG Kunshan3, YAO Zhengquan3, WANG Xuchen5_L
Late Quaternary sedimentary environmental evolution offshore of the Hangzhou Bay, East China—implications for sea level change and formation of Changjiang alongshore current
Chinese Journal of Oceanology and Limnology, 2015, 33(3): 748-763

Article History

Received Jun. 15, 2014;
accepted in principle Sep. 3, 2014;
accepted for publication Oct. 24, 2014
Late Quaternary sedimentary environmental evolution offshore of the Hangzhou Bay, East China—implications for sea level change and formation of Changjiang alongshore current
WANG Xin(王昕)1,2, SHI Xuefa(石学法)3 , WANG Guoqing(王国庆)4, QIAO Shuqing(乔淑卿)3, WANG Kunshan(王昆山)3, YAO Zhengquan(姚政权)3, WANG Xuchen(王旭晨)5       
1 Institute of Oceanology, Chinese Academy of Sciences, Key Laboratory of Marine Geology and Environment, Qingdao 266071, China;
2 University of Chinese Academy of Sciences, Beijing 100049, China;
3 Key Laboratory of Marine Sedimentology & Environmental Geology, First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China;
4 Faculty of Earth Science, China University of Geosciences, Wuhan 430074, China;
5 University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA02125, USA
ABSTRACT:This study focuses on sedimentary environmental changes offshore of Hangzhou Bay, East China, since the Late Quaternary. AMS 14C ages from core CJK10, lithologies, distribution of foraminifera, heavy minerals, and S and Cl elements show a fluvial terrace environment during ~23.2-11.0 cal ka BP; a littoral to tidal-flat environment during 11.0-10.2 cal ka BP; and a shallow marine environment with a relatively low sedimentation rate (0.1-0.22 cm/a) since 4.3 cal ka BP. High depositional rates (~1.6 cm/a) from 10.9 to 10.2 cal ka BP resulted from sufficient accommodation space created by rapid sea level rise from -44 m to -33 m, from high sediment delivery by local rivers, and effective trapping of sediments by tidal-flat vegetation. The rate of sea level rise was variable; relatively high from 10.9 to 10.6 cal ka BP (2.1 cm/a), and lower since 10.6 cal ka BP (1.2 cm/a). The Changjiang alongshore current crossed the Hangzhou Bay to form the mud wedge on the inner shelf of the East China Sea later than 9.4 cal ka BP. The CJK10 site was a tide-dominated shelf environment and experienced erosion from approximately 9.4-9.2 cal ka BP to 4.3 cal ka BP. The depositional hiatus was caused by the Changjiang alongshore current, which was relatively weak during 9.4-7.5 cal ka BP and increased in strength during ~7.5-4 cal ka BP. From ~4.3 cal ka BP, a large amount of sediment from the Changjiang River was partly deposited on the continental shelf of Hangzhou Bay with some transported southward. Therefore, this study clarifies the history of Changjiang-derived sediment dispersal and deposition, although a detailed record of the changes in the Changjiang alongshore current since 4.3 cal ka BP is difficult to obtain because of the scarcity of evidence.
Key words: continental shelf off Hangzhou Bay     East China Sea mud wedge     Changjiang alongshore current     sediments transportation and deposition     postglacial sea level    

Since the Cenozoic,the rise of the Qinghai-TibetPlateau has formed the high relief of the Himalaya,and the tension fracturing of the marginal seas of thewestern Pacifi c Ocean. This dramatic l and formchange of the Asia-Pacifi c region contributed to the origin of a number of large Asian rivers,such as theHuanghe(Yellow),Changjiang(Yangtze),Red,Mekong,Indus,and Ganges-Brahmaputra Rivers.Such a large number of “mega river” systems plays animportant role in transporting large sediment and suspended material loads to the ocean(Burbank,1992; Brookfeld,1998; Li et al.,2000; Yang et al.,2001; Wang,2004). The sediment budget of theseAsian rivers accounts for more than 70% of the totalglobal suspended sediment load(Milliman and Syvitski,1992). Most of these sediments becometrapped in estuaries and adjacent continental shelves.The evolution of these depositional environments and the sediment dispersal processes have thereforegained substantial attention from earth scientists.

In recent decades,numerous geological and geophysical studies have revealed the fate ofsediments derived from the Changjiang River. Thisincludes studies on the Holocene environmentalchanges of the Changjiang estuary,delta,and theinner shelf of the East China Sea(ECS)(Chen and Stanley,1993; Chen et al.,2000; Li et al.,20002002; Hori et al.,2001ab2002ab; Tao et al.,2006;Yi et al.,2006; Liu et al.,20072010; Wang et al.,2010; Xu et al.,2012). The fate of the Changjiang River material and the formation of the ECS mud beltare dominated by the circulation and strength ofcurrents over the ECS inner shelf(Fig. 1). TheKuroshio Warm Current(KWC) and the TaiwanWarm current(TWC)fl ow northward. In winter,the Changjiang alongshore current,including the Changjiang River Diluted Water(CDW) and theZhejiang Fujian Coastal Current(ZFCC),fl owssouthward. A large amount of the sediment loaddeposited around the subaqueous delta and the northHangzhou Bay is subsequently eroded periodically and transported southward by the Changjiangalongshore current to form “the mud belt deposit onthe inner shelf of the ECS”(Qin et al.,1987; Liu et al.,2007; Wang et al.,2013). The dispersion ofsuspended sediment to the ECS is constrained westof 123°E by the TWC(Yun,2010).

Fig. 1 Bathymetry and regional ocean circulation pattern inthe East China and Yellow Seas

KWC: Kuroshio Warm Current; TWC: Taiwan Warm Current;YSWC: Yellow Sea Warm Current; SSCC: South Sh and ong CoastalCurrent; JCC: Jiangsu Coastal Current; CDW: Changjiang DilutedWater; ZFCC: Zhejiang Fujian Coastal Current. Redraw according to Qin et al.(1987)Hu and Yang(2001),and Su,(2001).

Wang et al.(2008a)have proposed the formationof the alongshore current and the arrival of Changjiangsediment material to the ECS inner shelf since 10 kaBP based on grain-size analyses of core MD06-3040(27.70°N,121.78°E,with a water depth of 47 m).However,Xu et al.(2009)concluded that theformation of the Changjiang alongshore current and the transport southward of Changjiang-derivedmaterials occurred at 12.3 ka BP based on the sedimentgrain-size data of core EC2005(27.42°N,121.33°E,with a water depth of 36 m). Evidence from thebottom age of a high-st and system tract(HST)in theECS and the foraminifera record appear to support the infl uence of KWC,TWC,and ZFCC on the ECSinner shelf from approximately 8–7 ka BP(Jian et al.,2000; Liu et al.,2007; Zhao et al.,2009). The ZFCCstrengthened between 5.1–2.8 cal ka BP,concurrentwith the low sedimentation rate in the subaqueousdelta during 6–4 cal ka BP(Wang et al.,2010).Therefore,it is uncertain when and why the Changjiang alongshore current crossed the HangzhouBay to form the mud wedge on the inner shelf of theECS.

The continental shelf area off Hangzhou Bay is animportant passage,and trap,for sediments from the Changjiang River. The sedimentary environmentevolution of this area can provide insight into thehistory of Changjiang-derived sediment dispersal and deposition. Here,we focus on the Hangzhou Baycontinental shelf deposits to investigate thesedimentary environment changes,and reveal thedispersal and distribution pattern of sedimentarymaterial carried by the Changjiang River. In addition,this work provides the opportunity to compare thedepositional systems of the offshore area with thoseof the paleo-incised valley and subaqueous delta.

Fig. 2 Map of the study area showing borehole locations inoffshore of Hangzhou Bay,China

The water depth at the CJK10 borehole site is 25.3 m. Data ofboreholes HQ98,CM97,and ZK9 are from Hori et al.(2001b) and Wang et al.(2010).


In November 2008,a 30.6-m-long borehole coreCJK10 was drilled offshore of Hangzhou Bay(30.61°N,122.60°E,Fig. 1)using the rigging methodin water 25.3-m-deep,with a recovery of 91.1%. Thecore was split,described,and sub-sampled in thelaboratory. The samples for AMS 14C dating(benthic foraminifera and plant fragments)were pickedmanually(Table 1). Plant samples were picked out and identifi ed with the naked eye. Benthic foraminiferawere separated from sieved material under amicroscope. The 14C ages of 12 samples weremeasured at the National Ocean Sciences AcceleratorMass Spectrometry(NOSAMS)Facility,of theWoods Hole Oceanographic Institution,Woods Hole,MA,USA. The ratios of 14C/ 12C were measured forage determination and the δ13C corrections for isotopefractionation were made. All radiocarbon ages werecalibrated(cal a BP)using the Calib Rev 6.1(beta)program(Stuiver and Reimer,1993). The Marine09calibration dataset was used for the foraminiferasamples. The marine reservoir effect(ΔR)wasregarded as -100±36,based on Southon et al.(2002) and Kong and Lee(2005). Final calibrated ages at the1σ confi dence level with probabilities >0.8 areregarded in this study as reliable.

Table 1 AMS 14C ages of shell and plant samples from core CJK10

A total of 255 samples for grain-size analyses werepretreated with a 30% H2 O2 solution to removeorganic matter,and with 3 mol/L HCl solution toremove carbonate. Grain-size analysis was measuredwith a Mastersizer 2000 laser particle size analyzer.The measurement range of the instrument is 0.02–2 000 μm,with a resolution of 0.01 Φ. The repeatedmeasurement error is <3%.

Micropaleontological analysis of 18 samples wasconducted at intervals of 70–150 cm or the uppermost20.4 m of the core using the st and ard treatmentmethod(Wang et al.,1985)at the Key Laboratory of Marine Geology,Tongji University,Shanghai,China.

Heavy mineral analysis was performed on the veryfi ne s and fraction(0.063–0.125 mm)for 52 sedimentsamples at intervals of 20–100 cm. Dry samples of~200 g were wet-sieved using a 62.5-μm nylon mesh.Approximately 2 g of dry sample of the very fi ne s and fraction was separated using bromoform with aspecifi c density of 2.889–2.891 at 20±1°C. For heavymineral examinations,line counts of more than 300grains were identifi ed under a stereoscope(OlympusSZX16,Olympus Corporation,Tokyo,Japan) and apolarizing microscope(Olympus BX51). Detritus and weathered minerals were treated as a separate mineralcategory.

The relative content of S and Cl was tested usingan Itrax core scanner. This high-resolution X-rayfl uorescence(XRF)tool can determine the amount of,and fl uctuations within,the chemical species along asplit core(Jansen et al.,1998; Haschke et al.,2002;Croudace et al.,2006; Richter et al.,2006). XRFscans were made every 1 cm.

With the exception of AMS 14C dating and micropaleontological analysis,all pretreatment work and tests were done at the Key Laboratory of MarineSedimentology and Environmental Geology,StateOceanic Administration,Qingdao,China.3 RESULT 3.1 Lithology,14C ages and distribution of S and Cl

Based on the lithology,S and Cl content,benthicforaminifera distribution,and 14C ages,we dividedthe borehole sediments into four units(Fig. 3).

Fig. 3 Composite depth profi le of core CJK10 showing calibrated calendar ages,lithology,grain-size analyses,distribution of foraminifera,S and Cl content,and interpretationof sedimentary facies

MZ: mean grain size.

Unit 1(30.6–21.7 m)

Sediments are predominantly yellow and brownishyellow fi ne s and ,with parallel bedding(Fig. 4,22.9–30.6 m). The sediment consists of 61.5%–96.6%s and ,3.4%–33.5% silt,and 0–1.6% clay. The meangrain size(Φ)is in the range of 2.4–4.1. The S and Clcontent was ~0 counts per second(cps).

Fig. 4 Scale photographs of core CJK10,with depth decreasing from bottom right to top left
30.6–22.9 m: yellow and brownish fi ne s and with parallel bedding; 21.5–17.25 m: predominantly stiff mud; 16.96–16.65 m: some silty intercalations; 16.4–16.1 m: open apertures(red circle)caused by plant decay; 15.3–8 m: concretions,oxidation spots,plant fragments,and occasional gastropods; 7.8–5.82 m:dry,slightly greenish gray concretions,vertical plant fragments and complete gastropods shells; 5.2–1.2 m: gray mud with silty laminations; 0.7–0.4 m:yellowish gray mud with abundant silty laminations.

Unit 2(21.7–17.2 m)

This unit has brownish yellow and bluish gray todark gray hard mud(Fig. 4,21.5–17.25 m),and verythin plant fragments are common. Silt is dominant(75.1%–86.1%),followed by clay(12.5%–22.0%) and s and (0.8%–12.1%). The mean Φ is in the rangeof 5.9–6.8. No foraminifera were found. A 14C age of22 999–23 555 cal a BP was obtained at 20.9 m depth(Table 1).

Unit 3(17.2–5.2 m,including Units 3a and 3b)

This unit is characterized by gray mud with many dry,greenish gray concretions,plant fragments,and complete gastropods,especially from 8.1 m to 5.2 m(Fig. 4,7.8–5.82 m). Many intercalations of silt laminae(Fig. 4,16.4–16.1 m,0.2–0.5-cm-thick) and organiclaminae are present in the lower part of this section(17.2–16.15 m). Sediment between 8.1–5.2 m are veryviscous and stiff,resulting in some damage to the coreduring splitting. Silt(65.2%–83.2%)is dominant inthis unit,followed by clay(7.7%–33.3%) and s and (0–19.1%). The mean value of Φ varies from 5.2 to 7.6.The S content increases abruptly from a mean value of~200 cps to 400–600 cps at a depth of 17.2 m,and thenreaches its maximum(nearly 1 000 cps)with largefl uctuations throughout the unit. The Cl content(300–2 500 cps)increases gradually towards the uppermostpart of the unit. Foraminifera are more widelydistributed in this section compared with the underlyingtwo units,with abundances in the range of 3–34/g.Radiocarbon ages were determined at 16.25 m(10 703–11 068 cal a BP),15.4 m(10 516–10 653 cal a BP),8.4 m(10 650–10 755 cal a BP),6.8 m(10 587–10 699 cal a BP),5.95 m(11 204–11 269 cal a BP),and 5.55 m(10 166–10 231 cal a BP)(Table 1).

Unit 4(5.2–0 m)

An erosive surface occurs at 5.2 m. A 3-cm-thickdark gray mud layer with high organic content overliesthis discontinuous contact. Sediments overlying theorganic-rich layer comprise gray and yellowish graymud,with some silty laminations or clumps of siltymaterial. The sediments consist of silt(52.2%–81.0%),clay(10.5%–30.5%) and s and (0.1%–37.4%).The mean value of Φ is in the range of 5.3–7.3. The Scontent in this section of the core fl uctuates less thanthat in unit 3,and is in the range of 200–400 cps. TheCl content is higher than in the rest of the core,increasing from 2 000 cps to 4 000 cps. Foraminiferaare ubiquitous through the section with abundances of4–21/g. Radiocarbon ages were determined at 5.2 m(10 185–10 236 cal a BP,obtained from completegastropod shell),5.2 m(10 406–10 536 cal a BP,obtained from organic-rich mud),5.15 m(4 297–4 424 cal a BP),3.35 m(3 056–3 196 cal a BP),and 3.0 m(3 294–3 394 cal a BP)(Table 1). 3.2 Foraminifera assemblages(FA)

A total of 57 species of benthic foraminifera wereidentifi ed from 2 658 tests,with predominantlyeuryhaline and littoral species. Descriptions of theforaminifera assemblage(FA)in each unit are asfollows(Fig. 5):

Fig. 5 Benthic foraminifera abundance(/g) and frequency(%)in core CJK10

(FA1)Unit 2: no foraminifera were observed.

(FA2)Unit 3: foraminifera occur in the fi ve samplesobtained from 17.2–11.0 m,but commonly with lowabundances(3–7/g) and diversity,with the exceptionof the bottom part in which the abundance is relativelyhigh(34/g at 17.1 m,Fig. 5). This assemblage isdominated by Ammonia beccarii,Elphidiellakiangsuensis ,and Helenina and erseni .

(FA3)11.0–5.2 m,the foraminiferal abundanceincreased to 11–53/g(Figs.3,5). The assemblages aredominated by Ammonia beccarii(37.6%–65.1%),Elphidiella kiangsuensis(3.4%–15.3%),and Trochammina inflata(0.8%–14.5%). Cribrononionporisuturalis,Pseudononionella variabilis,Pseudogyroidina sinensis ,and Pseudoeponides nakazatoensis are first observed in this unit,usuallywith a relatively high content. The number ofHaynesina germanica and Helenina and erseniapproaches zero at a depth of ~11.0 m and ~8.1 m,respectively. Elphidium advenum,Quinqueloculinalamarckiana,Sigmoilopsis asperula,Hanzawaianipponica,Florilus atlantica,and Pararotalianipponica appear sporadically between 8.1–5 m.

(FA4)Unit 4: the foraminifera have an abundanceof 4–21/g. Quinqueloculina(lamarckiana+seminula)(11.2%–24.8%),Ammonia maruhasii(9.9%–21.9%),Elphidium advenum(1.5%–22.6%),Arenoparellaasiatica(5.7%–13.8%),and Sigmoilopsis asperula(3.1%–12.8%)predominate in this interval. Ammonia annectens+Ammonia compressiuscula(1.5%–7.8%),Hanzawaia nipponica(1.5%–8.5%),and Florilusspp.(3.1%–6.2%)were observed at lowconcentrations. Pararotalia nipponica,Elphidiummagellanicum,Spiroloculina communis,Laagenaspp.,Bolivina cockei,Guttulina spp.,and Brizalinastriatula appear sporadically.3.3 Heavy mineral assemblages

Thirty-one types of heavy mineral were identifi ed in core CJK10. The stratigraphic distribution of somerepresentative types is shown in Fig. 6. The heavymineral assemblage limits match the lithologicalunits,except for unit 3 in which two assemblageshave been identified.

Fig. 6 Heavy mineral distribution in the CJK10 borehole

Unit 1 contains an average of 43.9% hornblende,29.8% epidote,6.3% mica,5.0% pyroxene,and 3.5%hypersthene. Ilmenite,magnetite,limonite,hematite,pyrite,and siderite are rare.

Siderite dominates unit 2,with a content of 84.3%–99.7%.

In unit 3a,pyrite(28.0%)occurs between 17.2 m and 11.0 m,whereas no siderite was observed. Pyrite,hornblende(24.8%,usually with granular and stubbycolumnarmorphologies,green,and light green),limonite(17.3%),epidote(11.4%,usually stronglyweathered),ilmenite(5.2%,usually as smallgranules),and pyroxene(5.1%,usually granular)arethe dominant heavy mineral species in this section.Limonite(45.6%),pyrite(27.3%),and hematite(9.1%)predominate between ~11.0–9.0 m,whilehornblende,epidote,and mica are rare. Massive and yellowish red pyrite is very abundant in unit 3,especially in unit 3b(~9.0–5.2 m),approaching95.2%. Conversely,pyrite is rare or was not observedin the rest of the units.

The heavy mineral assemblage of unit 4 is similarto that of unit 1,but with a higher content of ilmenite(usually forming small granules showing surfacecorrosion),magnetite(usually granular and oxidized),and pyrite(mainly small and granular),and a lowermica content(Fig. 6).4 DISCUSSION 4.1 Age determination and sedimentation rate

The age of unit 1 could not be confi rmed becauseof a lack of AMS 14C data. Unit 2 was deposited duringapproximately 23.2–11.0 cal ka BP. The agesdetermined for unit 3 are tightly grouped,making itdiffi cult to discern specifi c ages for small-scalesediment packages within this section. The marinesediments of unit 4 formed mainly since 4.3 cal ka BP when sea level was close to the present level. The3-cm-thick organic-rich mud at the top of unit 3 isdirectly overlain by these marine sediments. This thinlayer most likely consists of reworked material duringthe transgression. Considering the lithology of unit 3,mainly gray mud with many concretions,plantfragments,and complete gastropods,we regard thegastropods as an in situ index of the sedimentaryenvironment. As a result,the 10.2 cal ka BP obtainedfrom the gastropod shells at 5.2 m is likely to be moreaccurate than the age of 10.6 cal ka BP determinedfrom the organic mud. We therefore infer thatsediments at a depth of 16.15–5.2 m were mainlydeposited during the period of 10.9–10.2 cal ka BP.Tightly grouped ages may refl ect a high sedimentationrate of nearly 1.6 cm/ a(Fig. 7). The climate was warm and wet during 11.4–9.2 cal ka BP(Dykoski et al.,2005; Shao et al.,2006). Therefore,the rate ofsediment supply during this period can be regarded asconstant. Based on the 1.6 cm/ a sedimentation rate,we determined an age of ~11.0 cal ka BP and 10.6 calka BP at core depths of 17.2 m and 11.0 m,respectively.The ages at 3.0 m and 3.35 m(Table 1)appearstratigraphically reversed,most likely because thesediments were reworked. The presence of siltylaminations in the predominantly muddy material at5.5–3.3 m(Figs.3,4)implies that there was a relativeincrease in pulses of hydrodynamic energy,whichmay have caused reworking of surface sediments.Considering the similarity of the two ages(3 180±20 and 3 360±15 cal a BP),we adopted an average age of~3.2 cal ka BP for the sediments at ~3.2 m depth tocalculate the sedimentation rate.

Fig. 7 Sediment-accumulation curve for core CJK10determined from calibrated 14C ages(Table 1)

The age of 10.4 cal ka BP at -5.2 m may be erroneously old. Theages of 10.9 cal ka BP and 10.2 cal ka BP at depths -16.25 m and -5.2 m,respectively,were used to calculate the sedimentation rateduring this period. The ages at -3.35 m and -3.0 m are consideredto be reworked and therefore an average of ~3.2 cal ka BP wasadopted for this depth.

The sediment accumulation curve is presented inFig. 7 and shows a particularly low sedimentation rate(~0.04 cm/ a)from 23.2–10.9 cal ka BP. No sedimentsdated at 10.2–4.3 cal ka BP are preserved in coreCJK10. Sedimentation was relatively slow during theperiods of 4.3–3.2 cal ka BP and 3.2–0 cal ka BP withrates of ~0.22 cm/ a and ~0.1 cm/ a,respectively.4.2 Interpretation of sedimentary facies

(1)Fluvial environment in unit 1

The color of sediments in unit 1(yellow and brownish yellow,Fig. 4)indicates an oxidizingterrestrial environment. Element S exists in forms S2-,[S2]2-,S0,S4+,and S6+ . In the oxidizing condition,element S in the low valence state(i.e.,S 2-,[S2] 2-)canconvert to S4+,and fi nally be oxidized to S6+ in theform of sulfate. Most sulfate with high solubility canbe transported by rivers to the ocean(Liu et al.,1984). In addition,the content of element Cl is also high inthe marine realm. Therefore,high S and Cl contentcan be observed in marine sediments. Low S and Clcontent was observed in unit 1(Fig. 3),potentiallyindicating a terrestrial environment. The relativelycoarse sediments of s and with parallel beddingstructures in unit 1(Fig. 4)demonstrates a high energy,possibly fl uvial,environment.

(2)A fl uvial terrace environment in unit 2

The lithology of unit 2 is the same as that of thefi rst stiff mud on the Changjiang coast. Siderite,representative of this stiff mud of the ChangjiangRiver delta plain(Jin et al.,2007),is extremelyabundant(~84.3%–99.7%)in unit 2(Fig. 6). As aresult,we can conclude that the sediments in unit 2were mainly stiff mud. The stiff mud,consisting of apaleosoil,experienced pedogenesis in the sea-levellow-st and Marine Isotope Stage 2(MIS 2),and earlydiagenesis after paleointerfl uve inundation by the sealevelrise during MIS 1(Li et al.,2000; Qin et al.,2008). During MIS 2 global sea level wasapproximately 120–130 m below the present level(Yang and Xie,1984; Fairbanks,1989). The riversincised deeply,and the paleointerfl uves weresuperaqueously exposed and experiencedpedogenesis. With postglacial sea level rise,interfl uves began to be in fluenced by sea water,pedogenesis subsequently stopped,and earlydiagenesis began,producing the stiff aspect of thismud. The sediments in unit 2 were therefore related toan interfl uve depositional environment during 23.2–11 cal ka BP,which was not in fluenced by sea wateras indicated by no observations of foraminifera(Fig. 5). A fl uvial terrace environment is a potentialexplanation for unit 2 of core CJK10(Fig. 3).

(3)A supra tidal fl at to upper tidal fl at and saltmarsh environment in unit 3

The sediments in unit 3,including mainly graymud with greenish gray concretions,plant fragments,and complete gastropod shells,are sediments typicalof upper and supra tidal flats. The S content increasesabruptly from ~200 cps to ~400–600 cps at 17.2 m,and then to ~1 000 cps at a depth of ~16.7–16.6 m(Fig. 3). This sharp increase of S denotes a reducingenvironment. However,the Cl content remainsrelatively low(~400–600 cps)at 17.2–16.15 m(Fig. 3). This indicates that a reducing environmentwith little to no infl uence by seawater dominates atthis depth range. The abrupt emergence of foraminiferaat 17.1 m(Figs.3,5)may have been caused byseawater intrusion over terrestrial sediments during storm tides. The presence of coarser silt intercalationsin this section(Fig. 4)suggests that the sedimentaryenvironment was not stable,and may have formedduring fl ooding,seawater intrusion,and /or stormtides. Therefore,a supra tidal fl at environment isinferred during ~11.0–10.9 cal ka BP,with occasionalinfl uxes of seawater,for sediments between 17.2 m and 16.15 m.

Sediments at a depth range of 16.15–11.0 m in unit3a are characterized by oligohaline foraminiferaspecies with very low abundance(3–7/g) and diversity. Only Ammonia beccarii,Elphidiellakiangsuensis,Helenina and erseni,and Haynisinagermanica are preserved in this section. Theseforaminifera are typical of modern intertidal flats ofthe Yellow Sea and the ECS with a salinity <15(Hua and Wang,1986; Hong,1987; Wang et al.,1988). Wetherefore interpret an upper tidal fl at between 16.15–11.0 m,which is close to mean high water(MHW) and was periodically submerged by sea water.

Foraminifera abundance increases from 3–7/g inunit 3a to 11–53/g in unit 3b(Fig. 5). A greaterdiversity of species appears towards the upper part ofunit 3b. Conversely,Haynesina germanica and Helenina and erseni decrease upward and are nolonger observed at a depth of ~11.0 m and ~8.1 m,respectively. Trochammina inflata,a typical saltmarsh species,is ubiquitous in unit 3b. The verticaldistribution of foraminifera in core CJK10 clearlyshows an increase in salinity. This is in agreementwith the constant,upward increase in Cl(Fig. 3). Unit3b is therefore defi ned as a sedimentary environmentof a salt marsh,which is located between MHW and the mean spring high water(MSHW).

Our interpretation also appears to be supported bythe distribution of pyrite and limonite in unit 3. Pyriteis diagnostic of an anoxic(i.e.,reducing)environment and ,if oxidized,would decompose to Fe(OH)3 and Fe 2 O 3 ·H2 O,and ultimately limonite(Li and Chen,1995; Jin et al.,2007). Relatively high proportions ofboth limonite(17.3%) and pyrite(28.0%)occurbelow 11.0 m depth(Fig. 6)which may,therefore,beclose to the oxidation-reduction interface. Thelimonite(Fig. 6)can be attributed to the transformationof pyrite at such an interface. In the early salt marshperiod,the environment was also dominated byoxidation,as shown by the much higher content oflimonite(45.6%)at 11.0–9.0 m. Conversely,reducingconditions dominated in the later salt marsh period,asrevealed by the abundance of pyrite and the lack oflimonite at depths of 8.1–5.2 m.

(4)Shallow marine environment in unit 4

The wide distribution of foraminifera,such asQuinqueloculina(lamarckiana+seminula),Ammoniamaruhasii,Elphidium advenum,Arenoparellaasiatica,and Sigmoilopsis asperula,between 5.2–0 mimply that a near-shore,shallow marine environmentexisted from ~4.3 cal ka BP. This is similar to thepresent environment,and is supported by the frequentoccurrence of modern,offshore species,e.g.,Ammonia annectens,A . compressiuscula,Hanzawaianipponica,and Florilus spp.4.3 ECS sea level fl uctuation with emphasis on10.9–10.2 cal ka BP

Records from tidal and supra tidal flats are goodindicators of relative sea level(RSL). Age pointsderived from unit 3 of core CJK10(Table 1)providea relatively accurate constraint on the ECS sea levelrise during 10.9–10.2 cal ka BP(Fig. 8). Because theupper tidal fl at is close to the MHW,half the tidalrange of 1.5 m(Shou et al.,2009)was subtractedfrom the elevation of the data points to reconstructECS RSL. Similarly,as the supra tidal fl at and saltmarsh were located between the MHW and MSHW,approximately 2.5 m was subtracted from thesediment elevation for RSL calibration. Core CJK10is located in the vicinity of the Zhoushan archipelago,in the middle of the Zhejiang-Fujian up lift. This studyarea has been up lifted since the Quaternary,whiletectonic subsidence has dominated the ECScontinental shelf plain. The amplitude of the neotectonicmovement in this study area has been minorsince the Holocene(Wang,1995). The tectonicsubsidence and up lift can therefore be neglected forthe RSL calculation. In addition,sedimentconsolidation reduction has not been consideredbecause only 5.2-m-thick sediments overlay theunderlying tidal fl at layer.

Fig. 8 Relative sea level during 12–9 cal ka BP

A . ECS RSL(m)during 11–10.2 cal ka BP. The dark gray line wascalculated based on the AMS-14C ages of tidal flat sediments from CJK10(dots). The dashed line was estimated. The light gray line is from Liu and Milliman(2004). Terrestrial peat: squares; inter-subtidal: solid triangles;shallow marine: hollow triangles; B. Barbados RSL(m)from Peltier and Fairbanks(2006). Core 12: squares; core 7: dots; core 16: triangles; C.Tahiti RSL(m)from Bard et al.(2010). Core P6: dots; core P7: squares;core P8: triangles; core P9: quadrangular; core P10: diamonds.

Based on the calculation,the ECS RSL wasapproximately -45 m below present sea level around11 cal ka BP,-44 m around 10.9 cal ka BP,-37.8 maround 10.6 cal ka BP,and -33 m around 10.2 cal kaBP. The ECS RSL continued rising at an average rateof 1.6 cm/ a(Fig. 8,dark gray)during 10.9–10.2 cal kaBP. However,the sea level rise in the ECS wasvariable,relatively higher during 10.9–10.6 cal ka BP(~2.1 cm/ a),and lower since 10.6 cal ka BP(~1.2 cm/ a). The sedimentation rate is presumed to beconstant(1.6 cm/ a)during 11.4–9.2 cal ka BP(Fig. 7).Once the rate of sea level rise falls below this constant,there will be surplus sediments after the accommodation space created by sea level rise isfi lled. These redundant sediments can then result in aseaward progradation of the coastal environment. Thedeceleration of sea level rise around 10.6 cal ka BPcorresponds well with sedimentary face change fromupper tidal fl at to salt marsh. Similarly,the accelerationaround ~10.9 cal ka BP is in good agreement withsedimentary face change from supra tidal to upperintertidal fl at. Otherwise,there would not be enoughaccommodation space for the rapid sedimentationduring 10.9–10.6 cal ka BP.

Figure 8 shows a comparison between data fromCJK10 and previous data from Liu and Milliman(2004)(Fig. 8A,light gray),Barbados(Peltier and Fairbanks,2006),and Tahiti(Bard et al.,2010)in alonger time window of 12–9 cal ka BP. Combinedwith AMS- 14C ages,also obtained from inter-subtidalmaterial from Liu and Milliman(2004),the sea levelrise curve can be approximately reconstructed as thedashed line suggests. The rapid sea level rise(~20 m)during MWP-1B may have been overestimated in Liu and Milliman(2004). The prominent step in MWP-1B,observed in Barbados(Peltier and Fairbanks,2006),is not apparent in ECS as indicated by theCJK10 records. Differences also exist between theECS RSL and the Tahiti RSL(Bard et al.,2010),which exhibited no prominent sea level step duringMWP-1B and yields a constant high sedimentationrate of 1.2 cm/ a since 11.4 cal ka BP(Bard et al.,2010).4.4 Depositional evolution offshore of HangzhouBay

Because of the scarcity of age data in unit 1,wewill discuss the evolution of the postglacialsedimentary environment of the continental shelfoffshore of Hangzhou Bay since ~23.2 cal ka BP,which was clearly controlled by deglacial sea levelchange. Before 11.0 cal ka BP,the ECS RSL waslower than -45 m(Fig. 8). Likely because of thetectonic elevation,this study area was subaeriallyexposed and experienced strong weathering before11 cal ka BP(Fig. 9a). A fl uvial terrace without theinfl uence of sea water dominated during 23.2–11 calka BP. Meanwhile,some terrain with low elevation(i.e.,a valley)may have been in fluenced by the sea and changed to a tidal-fl at environment(as suggestedby ZK9 in the subaqueous delta),or to a tidal riverenvironment(as suggested by HQ98 and CM97 in the paleo-incised valley)around 11.5–11 cal ka BP(Hori et al.,2001b; Liu and Milliman,2010; Wang et al.,2010)(Fig. 10). It is clear that Changjiang Riversediments had not been delivered to this study areabefore ~11 cal ka BP.

Fig. 9 Sketches of the evolution of the depositional environment

The arrows in each panel indicate the direction of the Changjiang sediment dispersal. The shaded area represents the depocenter of the Changjiang sedimentduring each period. The bold line denotes the paleocoastline inferred from the contemporary sea level. In panel b,the solid line corresponds to 10.2–9.4 calka BP and the dashed line to ~9–8 cal ka BP. In panel c,the bold line indicates the paleocoastline at ~7 cal ka BP.

Fig. 10 Comparison of the sedimentary environmental evolution shown by cores from the paleo-incised valley(HQ98,CM97),subaqueous(ZK9),and offshore of Hangzhou Bay(CJK10)

Sedimentary facies: UTF,upper tidal fl at; LISTF,lower intertidal to subtidal fl at; MISTF,muddy intertidal to subtidal fl at. The dashed lines representisochrones.

The ECS RSL rise from ~45 m to 33 m belowpresent sea level(Fig. 8)occurred between 11–10.2 calka BP. As the sea continued to rise,this study areabegan to be in fluenced by seawater,as suggested bythe extensively preserved foraminifera in unit 3(Fig. 5). The environment changed to a supra tidal fl atin 11 cal ka BP,and ultimately to an upper tidal fl at in10.9 cal ka BP due to a coeval acceleration of sealevelrise. The high accumulation at core depths16.25–5.2 m(elevation -41.55 m to -30.5 m,Fig. 7)was the result of suffi cient accommodation spacecreated by this sea level rise acceleration and theabundant sediment supply because of the warm and wet climate(Dykoski et al.,2005; Shao et al.,2006).A salt marsh formed at 10.6 cal ka BP because of thedeceleration of the sea-level rise. The heavy mineralassemblage of the tidal fl at sediments,mainlyauthigenic pyrite and limonite(Fig. 6),is similar to that of small semi-enclosed bays and tidal flats ofisl and s adjacent to the Zhejiang coast(Ma,1989).Studies of such modern sedimentary environmentsshow that the hydrodynamic energy is low,with littleimpact by waves,tides,and alongshore currents.Sediments with relatively high organic content aremainly supplied by small coastal rivers and creeks(Ma,1989). Similarly,the high sedimentation rateduring 11–10.2 cal ka BP in CJK10 was mainlycontributed by terrigenous sediment from localcoastal rivers(Figs.3,7). The organic-rich terrigenousmaterial boosts the growth and maintenance of tidal fl at plants,which helps trap and bind the substantialfl uvial sediments from local rivers. This highsedimentation rate was unfavorable to the oxidationof organic material and as a result contributed to arelatively high content of authigenic minerals(Fig. 6)(Rothwell,1989).

During 10.2–9.4 cal ka BP,the sea level rose at astable rate of ~1.2 cm/ a(Fig. 8). This rate was lowerthan the sediment supply rate of ~1.6 cm/a. We cantherefore conclude that some salt marsh or supra tidalfl at sediments would have been deposited during10.2–9.4 cal ka BP. Subsequently,the sea level rose to ~15–10 m below present level between ~9–8 cal kaBP. The sediment supply rate was much lower thanthe rate of sea level rise. If the Changjiang sedimentsupply to this study area was insuffi cient,thesediments deposited during 10.2–9.4 cal ka BP weremost likely eroded by increased estuary hydrodynamicenergy,such as tidal currents and wave action. Sucherosion phenomena were also observed in core ZK9(Fig. 9).

Large volumes of Changjiang River sediment weredeposited in the subaqueous delta and paleo-incisedvalley during ~10–8 cal ka BP indicated by the highaccumulation rates in ZK9,HQ98,and CM97 cores(shaded region in Fig. 9b,and Fig. 10)(Hori et al.,2002b; Hori and Saito,2007; Wang et al.,2010).During ~8–7 ka,most of the Changjiang Riversediments went into initiating the formation of the Changjiang River delta(Stanley and Warne,1994;Chen et al.,2000; Hori et al.,2002b; Hori and Saito,2007). Later,during ~7–4 ka,most of the ChangjiangRiver sediment became trapped in the paleo-incisedvalley of the Changjiang River(Wang et al.,2008b)(shaded section in Fig. 9c,and Fig. 10). After theincised valley had been fi lled,the sediments derivedfrom the Changjiang River began to be deposited onthe subaqueous delta from 5.9 cal ka BP(Wang et al.,2010). We can therefore conclude that the southwardtransport of the Changjiang River sediments waslower before 4.3 cal ka BP. The CJK10 site was still atide-dominated shelf environment from 9.4–9.2 cal kaBP to 4.3 cal ka BP(Fig. 9b and c). The longdepositional hiatus detected in the study area wasmost likely related to erosion in a tide-dominatedshelf environment.

The content of magnetite,ilmenite,and mica in the Changjiang sediments is relatively high,as has alsobeen found in previous studies(Lü and Yan,1981; He,1991). The higher content of ilmenite,magnetite,and mica in unit 1 than that in the other units may indicatethe infl uence of the Changjiang River sediments(Fig. 6). Long distance transport of the sedimentsresulted in ilmenite corrosion and magnetite oxidation.We can therefore conclude that a large amount ofsediment derived from the Changjiang River reachedthe southern study area after 4.3 cal ka BP,most likelyafter in filling the paleo-incised valley(Fig. 9d). Thelocal topography,namely archipelagos offshore ofHangzhou Bay,may have also in fluenced themovement of the Changjiang River sediments into thearea of core CJK10 and to the south,which occurredlater than the formation of the subaqueous delta.4.5 Implications for the Changjiang alongshorecurrent

The offshore area of Hangzhou Bay was dominatedby a salt marsh or a supra tidal fl at environment until9.4 cal ka BP. We can therefore conclude that the timewhen the Changjiang alongshore current crossed theHangzhou Bay to form the mud wedge on the innershelf of the ECS was later than 9.4 cal ka BP. If the Changjiang alongshore current exited before 9.4 calka BP,its pathway was to the west of its presentlocation and deeper than the 40–50 m isobath. The time of formation of the Changjiang alongshorecurrent in the study area was later than that of theestuary environment.

Sediments from the Changjiang River,thesubaqueous delta,and this study area were transportedsouth by the Changjiang alongshore current and contributed to the ECS inner shelf mud wedge. Thecirculation and strength of the Changjiang alongshorecurrent play an important role in sediment dispersal.Depositional environments and accumulation rates inthe southern(ECS inner shelf) and the northern(subaqueous delta,offshore of Hangzhou Bay)depocenters provide insight on how to reconstruct the Changjiang alongshore current(Fig. 1).

During ~10–4 ka,most of the Changjiang Riversediment became trapped in the paleo-incised valley and the subaqueous delta(Fig. 9b and c). Lowsedimentation rates during 9.4–7.5 cal ka BP at CJK10 and over the inner shelf mud wedge area,indicated byrecords from EC2005(<0.1 cm/ a) and cores MD06-3039 and 3040(~0.125 cm/ a)(Wang et al.,2008a; Xu et al.,2009; Zheng et al.,2010),suggest a relativelyweak Changjiang alongshore current. The sedimentaryhiatus at the northern depocenter and the deposition atthe southern depocenter(~0.19–0.68 cm/ a)during~7.5–4 cal ka BP suggest an increase in the Changjiangalongshore current. The northern depocenter isinferred to have experienced erosion since the middleHolocene sea-level highst and due to the Changjiangalongshore current,as indicated by the sedimentaryhiatus present in cores CJK10 and ZK9.

The Changjiang River sediment deposition atCJK10 since 4.3 cal ka BP may be related to either theincreased southward transport of Changjiang Riversediments because of the filling of the paleo-incisedvalley,or to an enhancement of the Changjiangalongshore current.5 CONCLUSION

(1)For the past 23.2 cal ka BP,three depositional systems have dominated the continental shelf offshoreof Hangzhou Bay. A fl uvial terrace environmentdominated during 23.2–11.0 cal ka BP; supra to uppertidal flats to salt marsh during 11.0–10.2 cal ka BP; and shallow marine environment from 4.3 cal ka BPto present,separated by an episode of erosion during10.2–4.3 cal ka BP. The changeover between theseenvironments was mainly in fluenced by postglacialsea level fl uctuations.

(2)ECS RSL around 11.0 cal ka BP wasapproximately -45 m below present sea level,and rose from -44 m to -33.0 m during 10.9–10.2 cal kaBP,with an average rate of 1.6 cm/a. The rate of sealevel rise was variable; relatively high during 10.9–10.6 cal ka BP(2.1 cm/ a),and lower since 10.6 cal kaBP(1.2 cm/ a).

(3)The CJK10 site was a tide-dominated shelfenvironment from 9.2–9.4 cal ka BP to 4.3 cal ka BP.From ~4.3 cal ka BP,a large amount of sediment fromthe Changjiang River was deposited on the continentalshelf of Hangzhou Bay and also transportedsouthward.

(4)The Changjiang alongshore current crossed theHangzhou Bay to form the mud wedge on the innershelf of the ECS later than 9.4 cal ka BP. Thedepositional hiatus at CJK10 was caused by the Changjiang alongshore current,which was relativelyweak during 9.4–7.5 cal ka BP and increased during~7.5–4 cal ka BP.6 ACKNOWLEDGMENT

We would like to thank the R/V Kan 407 for theirhelp with sampling on board,and the NOSAMSFacility at the Woods Hole Oceanographic Institutionfor the AMS 14C measurements.

Bard E, Hamelin B, Delanghe-Sabatier D. 2010. Deglacial meltwater pulse 1B and Younger Dryas sea levels revisited with boreholes at Tahiti. Science, 327 (5973): 1 235-1 237.
Brookfield M E. 1998. The evolution of the great river systems of southern Asia during the Cenozoic India-Asia collision: rivers draining southwards. Geomorphology, 22 (3-4): 285-312.
Burbank D W. 1992. Causes of recent Himalayan up lift deduced from deposited patterns in the Ganges basin.Nature, 357 (6380): 680-683.
Chen Z Y, Song B P, Wang Z H, Cai Y L. 2000. Late Quaternary evolution of the sub-aqueous Yangtze Delta, China: sedimentation, stratigraphy, palynology, and deformation.Marine Geology, 162 (2-4): 423-441.
Chen Z Y, Stanley D J. 1993. Yangtze Delta, eastern China: 2.Late Quaternary subsidence and deformation. Marine Geology, 112 (1-4): 13-21.
Croudace I W, Rindby A, Rothwell R G. 2006. ITRAX:Description and evaluation of a new multi-function X-ray core scanner. In : Rothwell RG ed. New Techniques in Sediment Core Analysis. Geological Society, London,Special Publications. p.51-63.
Dykoski C A, Edwards R L, Cheng H, Yuan D X, Cai Y J,Zhang M L, Lin Y S, Qing J M, An Z S, Revenaugh J. 2005. A high-resolution, absolute-dated Holocene and deglacial Asian monsoon record from Dongge Cave,China. Earth and Planetary Science Letters, 233 (1-2): 71-86.
Fairbanks R G. 1989. A 17,000-year glacio-eustatic sea level record: influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation. Nature, 342 (6250): 637-642.
Haschke M, Scholz W, Theis U, Nicolosi J, Scruggs B, Herzceg L. 2002. Description of a new micro-Xray spectrometer.J. Phys., IV France, 12 : 6-83.
He S L. 1991. Comparative study on terrigenous miniral component of sediment along nearshore area of the East China Sea. Journal of East China Normal University (Natural Science), (1): 78-86. (in Chinese with English abstract)
Hong X Q. 1987. Foraminifera distributions in coastal marsh along the Yellow Sea and the East China Sea and its geology implications. In : Yan Q S ed. Recent Yangtze Delta Deposits. 1st edn. East China Normal University ress, Shanghai, p.306-313. (in Chinese)
Hori K, Saito Y, Zhao Q H, Cheng X R, Wang P X, Sato Y, Li C X. 2001a. Sedimentary facies and Holocene progradation rates of the Changjiang (Yangtze) delta,China. Geomorphology, 41 (2-3): 233-248.
Hori K, Saito Y, Zhao Q H, Cheng X R, Wang P X, Sato Y, Li C X. 2001b. Sedimentary facies of the tide-dominated paleo-Changjiang (Yangtze) estuary during the last transgression. Marine Geology, 177 (3-4): 331-351.
Hori K, Saito Y, Zhao Q H, Wang P X. 2002a. Architecture and evolution of the tide-dominated Changjiang (Yangtze)River delta, China. Sedimentary Geology, 146 (3-4): 249-264.
Hori K, Saito Y, Zhao Q H, Wang P X. 2002b. Control of incised-valley fill stacking patterns by accelerated and decelerated sea-level rise: the Changjiang example during the last deglaciation. Geo-Marine Letters, 22 (3): 127-132.
Hori K, Saito Y. 2007. An early Holocene sea-level jump and delta initiation. Geophysical Research Letters, 34 (18):L18401,
Hu D X, Yang Z S. 2001. The Key Process of Ocean Flux in the East China Sea. Ocean Press, Beijing, China. p.3-13. (in Chinese)
Hua D, Wang Q Z. 1986. Characteristics of foraminiferal fauna in the surficial sediments of tidal flat in north coast of Hangzhou Bay. Donghai Marine Science, 4 (3):33-41. (in Chinese with English abstract)
Jansen J H F, Van der Gaast S J, Koster B, Vaars A J. 1998.CORTEX, a shipboard XRF-scanner for element analyses in split sediment cores. Marine Geology, 151 (1-4): 143-153.
Jian Z M, Wang P X, SaitoY, Wang J L, PflaumannU, ObaT,Chen X R. 2000. Holocene variability of the Kuroshio Current in the Okinawa Trough, northwestern Pacific Ocean. Earth and Planetary Science Letters, 184 (1): 305-319.
Jin B F, Zhang Y J, Song J. 2007. Characteristics of mineral chemistry and formation of the micro-nodules in the first stiff clay layer in the Yangtze River delta. Marine Geology & Quaternary Geology, 27 (3): 9-15. (in Chinese with English abstract)
Kong G S, Lee C W. 2005. Marine reservoir corrections (ΔR) for southern coastal waters of Korea. The Sea, Journal of the Korean Society of Oceanography, 10 (2): 124-128.
Li C X, Chen Q Q, Zhang J Q, Yang S Y, Fan D D. 2000.Stratigraphy and paleoenvironmental changes in the Yangtze Delta during the Late Quaternary. Journal of Asian Earth Sciences, 18 (4): 453-469.
Li C X, Wang P, Sun H P, Zhang J Q, Fan D D, Deng B. 2002.Late Quaternary incised-valley fill of the Yangtze delta (China): its stratigraphic framework and evolution.Sedimentary Geology, 152 (1-2): 133-158.
Li P, Chen G. 1995. Early diagenesis of late Pleistocene darkgreen stiff clay in the Yangzi River delta. Oil & Gas Geology, 16 (4): 313-319. (in Chinese with English abstract)
Liu J P, Milliman J D. 2004. Reconsidering melt-water pulses 1A and 1B: global impacts of rapid sea-level rise. Journal of Ocean University of China, 3 (2): 183-190.
Liu J P, Xu K H, Li A C, Milliman J D, Velozzi D M, Xiao S B,Yang Z S. 2007. Flux and fate of Yangtze River sediment delivered to the East China Sea. Geomorphology, 85 (3-4): 208-224.
Liu J, Saito Y, Kong X H, Wang H, Xiang L H, Wen C,Nakashima R. 2010. Sedimentary record of environmental evolution off the Yangtze River estuary, East China Sea, during the last -13,000 years, with special reference to the influence of the Yellow River on the Yangtze River delta during the last 600 years. Quaternary Science Reviews, 29 (17-18): 2 424-2 438.
Liu Y J, Cao L M, Li Z L, Wang H N, Chu T Q, Zhang J R. 1984. Element Geochemistry. Science Press, Beijing, China. p.458-489. (in Chinese)
Lü Q R, Yan S Z. 1981. A study of the heavy mincral groups in the Chang Jiang estuarine region and thier significance.Journal of East China Normal University Natural Science Edition, (1): 73-83. (in Chinese with English abstract)
Ma K J. 1989. A feature of the heavy mineral assemblage of the Zhejiang coastal region and the control factors.Donghai Marine Science, 7 (2): 33-45. (in Chinese with English abstract)
Milliman J D, Syvitski J P M. 1992. Geomorphic/tectonic control of sediment discharge to the ocean: the importance of small mountainous rivers. The Journal of Geology, 100 (5): 525-544.
Peltier W R, Fairbanks R G. 2006. Global glacial ice volume and Last Glacial Maximum duration from an extended Barbados sea level record. Quaternary Science Reviews, 25 (23-24): 3 322-3 337.
Qin J G, Wu G X, Zheng H B, Zhou Q. 2008. The palynology of the first hard clay layer (late Pleistocene) from the Yangtze delta, China. Review of Palaeobotany and Palynology, 149 (1-2): 63-72.
Qin Y S, Zhao Y Y, Chen L R, Zhao S L. 1987. Geology of the East China Sea. China Science Press, Beijing. 290p. (in Chinese)
Richter T O, van der Gaast S, Koster B, vaars A, Gieles R, de Stigter H C, de Haas H, van Weering T C E. 2006. The Avaatech XRF core scanner: technical description and applications to NE Atlantic sediments. In : Rothwell R G ed. New Techniques in Sediment Core Analysis. 1st edn.Special Publication, Geological Society, London, UK. p.39-50.
Rothwell R G. 1989. Minerals and Mineraloids in Marine Sediments: An Optical Identification Guide. Elsevier Science Publisher, New York, USA. p.161-166.
Shao X H, Wang Y J, Cheng H, Kong X G, Wu J Y. 2006.Holocene monsoon climate evolution and drought event recorded in the stalagmite from Shengnongjia, Hubei, China. Chinese Science Bulletin, 51 (1): 80-86. (in Chinese)
Shou W W, Wu J Z, Hu R J, Zhu L H. 2009. 3-D Hydrodynamic Numerical Modelling around the Sea Area of Zhoushan Islands. Marine Geology Letters, 25 (11): 1-9. (in Chinese with English abstract)
Southon J, Kashgarian M, Fontugne M, Metivier B, Yim W W S. 2002. Marine reservoir corrections for the Indian Ocean and Southeast Asia. Radiocarbon, 44 (1): 167-180.
Stanley D J, Warne A G. 1994. Worldwide initiation of Holocene marine deltas by deceleration of sea-level rise.Science, 265 (5169): 228-231.
Stuiver M, Reimer P J. 1993. Extended 14C data base and revised CALIB radiocarbon calibration program.Radiocarbon, 35 : 215-230.
Su J L. 2001. A review of circulation dynamics of the coastal oceans near China. Acta Oceanonlogica Sinica, 23(4): 1-16.
Tao J, Chen M T, Xu S Y. 2006. A Holocene environmental record from the southern Yangtze River delta, eastern China. Palaeogeography, Palaeoclimatology,Palaeoecology, 230 (3-4): 204-229.
Wang K, Zheng H B, Prins M, Zheng Y. 2008a. High-resolution paleoenvironmental record of the mud sediments of the East China Sea inner shelf. Marine Geology & Quaternary Geology, 28 (4): 1-10. (in Chinese with English abstract)
Wang P X, Min Q B, Bian Y H. 1985. Distribution of foraminifera and ostracoda in bottom sediments of the northwestern part of the South Huanghai (Yellow) Sea and its geological significance. In : Wang P X ed. Marine Micropaleontology of China. 1st edn. Springer, New York,USA. p.93-114. (in Chinese)
Wang P X, Zhang J J, Zhao Q H, Min Q B, Bian Y H, Zhen L F, Chen X R, Chen R H. 1988. Foraminifera and Ostracoda in Bottom Sediments of the East China Sea. China Ocean Press, Beijing, China. 438p. (in Chinese)
Wang P X. 2004. Cenozoic deformation and the history of sealand interactions in Asia. In : Clift P, Kuhnt W, Wang P,Hayes D eds. Geophysical Monograph Series 149,Continent-Ocean Interactions within East Asian Marginal Seas. 1st edn. American Geophysical Union, Washington D C USA. p.1-22.
Wang X, Shi X F, Wang G Q, Qiao S Q, Liu T. 2013.Sedimentation rates and its indication to distribution of Yangtze sediment supply around the Yangtze (Changjiang)River Estuary and its adjacent area, China. Earth Science-Journal of China University of Geosciences, 38 (4): 763-775. (in Chinese with English abstract)
Wang Y Z. 1995. On geologic tectonic background in Zhoushan archipelago area. South China Journal of Seismology, 15 (1): 5-61. (in Chinese with English abstract)
Wang Z H, Liu J P, Zhao B C. 2008b. Holocene depocenter shift in the middle-lower Changjiang River basins and coastal area in response to sea level change. Front Earth Sci., 2 (1): 17-26.
Wang Z H, Xu H, Zhan Q, Saito Y, He Z F, Xie J L, Li X, Dong Y H. 2010. Lithological and palynological evidence of late Quaternary depositional environments in the subaqueous Yangtze delta, China. Quaternary Research, 73 (3): 550-562.
Xu F J, Li A C, Xiao S B, Wan S M, Liu J G, Zhang Y C. 2009.Paleoenvironmental evolution in the inner shelf of the East China Sea since the last deglaciation. Acta Sedimentologica Sinica, 27 (1): 118-127. (in Chinese with English abstract)
Xu K H, Li A C, Liu J P, Milliman J D, Yang Z S, Liu C S, Kao S J, Wan S M, Xu F J. 2012. Provenance, structure, and formation of the mud wedge along inner continental shelf of the East China Sea: a synthesis of the Yangtze dispersal system. Marine Geology, 291-294 : 176-191.
Yang H R, Xie Z R. 1984. Sea-level changes along the east coast of China over the last 20,000 years. Oceanologia et Limnologia Sinica, 15 (1): 1-13. (in Chinese with English abstract)
Yang S Y, Li C X, Liu S G. 2001. Chemical fluxes of Asian rivers into oceans and their controlling factors. Marine Science Bulletin, 3 (2): 30-37.
Yi S, Saito Y, Yang D Y. 2006. Palynological evidence for Holocene environmental change in the Changjiang (Yangtze River) delta, China. Palaeogeography,Palaeoclimatology, Palaeoecology, 241 (1): 103-117.
Yun C X. 2010. Diagram of the Evolution of the Yangtze Delta.Ocean Press, Beijing, China. p.213-216. (in Chinese)
Zhao Q H, Jian Z M, Zhang Z X, Cheng X R, Wang K, Zheng H B. 2009. Holocene paleoenvironmental changes of the inner-shelf mud area of the East China Sea: evidence from foraminiferal faunas. Marine Geology & Quaternary Geology, 29 (2): 75-82. (in Chinese with English abstract)
Zheng Y, Kissel C, Zheng H B, Laj C, Wang K. 2010.Sedimentation on the inner shelf of the East China Sea: magnetic properties, diagenesis and paleoclimate implications. Marine Geology, 268 (1-4): 34-42.