關(guān)鍵詞深水重力流;濁流;物理模擬;數(shù)值模擬;研究進(jìn)展第一作者簡介,男,1997年生,博士研究生,深水沉積學(xué),E-mail:gjy201572211@163.com通信作者,男,教授,博士生導(dǎo)師,沉積學(xué)與儲(chǔ)層地質(zhì)學(xué),E-mail:xianbzh@cup.edu.cn
中圖分類號(hào) P512.2 文獻(xiàn)標(biāo)志碼A DOI: 10.14027/j.issn.1000-0550.2024.074 CSTR: 32268.14/j.cjxb.62-1038.2024.074
0 引言
深水重力流是由重力驅(qū)動(dòng)的,富含陸源碎屑的高密度流體[2-3],其攜帶的大量陸源碎屑在海底形成了地球上最大的復(fù)合沉積體,儲(chǔ)存了全球 35% 的深水油氣資源。現(xiàn)代海底監(jiān)測(cè)顯示,一期重力流事件可以攜帶超過 150km3 的沉積物,以 19m/s 的速度運(yùn)行,對(duì)海底通信電纜及輸油管道安全具有重大威脅。此外,深水重力流可以將大量陸源和海洋的有機(jī)碳輸送至深水環(huán)境,在地質(zhì)時(shí)間尺度上實(shí)現(xiàn)碳循環(huán)的中轉(zhuǎn)和匯聚,有助于調(diào)節(jié)全球氣候[4,8-9]。深水重力流具有典型的事件性特征,可以由火山噴發(fā)地震活動(dòng)[11-12]、風(fēng)暴[13-14]、洪水[15-17]等多種作用觸發(fā)。因此,重力流沉積也是地質(zhì)歷史時(shí)期洪水、火山或古地震等極端事件的有效記錄者。最新研究指出,重力流也可不需要明顯的外部觸發(fā)機(jī)制[8,超低濃度(沉積物含量約 0.07kg/m3 的羽流自加速同樣可以形成深水重力流,因此深水重力流的發(fā)生可能遠(yuǎn)比想象中更為頻繁。
自1888年Forel2報(bào)道日內(nèi)瓦湖密度流以來,重力流研究迅速發(fā)展。時(shí)至今日,眾多學(xué)者在重力流的沉積類型[21-24]和沉積模式[25-26等方面取得了長足的進(jìn)步。Middletonetal.根據(jù)顆粒支撐機(jī)理將重力流劃分為碎屑流、顆粒流、液化流和濁流4種類型;Lowe22依據(jù)流體流動(dòng)狀態(tài),將濁流進(jìn)一步分為高密度濁流和低密度濁流;Tallingetal.23根據(jù)流體黏土含量和流變學(xué)特征將碎屑流分為黏性碎屑流和非黏性碎屑流(砂質(zhì)碎屑流);Baasetal.24發(fā)現(xiàn)隨著重力流中黏土含量的增大,會(huì)出現(xiàn)一種介于牛頓流體和非牛頓流體之間的過渡型流體;Walker25結(jié)合古代露頭和現(xiàn)代實(shí)例,提出了經(jīng)典的海底扇模式;Shanmugam[26]總結(jié)了斜坡環(huán)境下滑塌型重力流的演化過程,建立了以碎屑流為主導(dǎo)的斜坡扇模式。近年來,由盆外洪水入海(湖)形成的洪水型重力流(異重流)引發(fā)了新一輪的重力流研究熱潮[27-29]。事實(shí)上,重力流沉積過程極為復(fù)雜,觸發(fā)機(jī)制[16.30-31]、流體性質(zhì)[23.32]、先存地貌[3-3等多種因素都可能導(dǎo)致沉積產(chǎn)物的巨大差異,經(jīng)典的沉積模式并非“萬能模板”,新的問題要求研究者們采取針對(duì)性的研究手段,提出更合理的解釋。
傳統(tǒng)的重力流研究主要依靠野外露頭、鉆井、地震等手段,以靜態(tài)沉積現(xiàn)象分析為基礎(chǔ)從而對(duì)沉積產(chǎn)物的形成過程[37-39]、影響因素[40-43]、分布模式[26.4進(jìn)行解釋?,F(xiàn)場(chǎng)觀測(cè)能夠直接獲取真實(shí)尺度下的動(dòng)態(tài)數(shù)據(jù),但限于深水重力流沉積事件的偶然性和發(fā)生場(chǎng)所的特殊性,現(xiàn)場(chǎng)流體監(jiān)測(cè)難度較大。相比之下,沉積模擬實(shí)驗(yàn)?zāi)軌蛟诓煌叨认峦ㄟ^控制邊界條件,再現(xiàn)各種自然環(huán)境中的沉積過程和水動(dòng)力特征,是理解和認(rèn)識(shí)深水重力流沉積動(dòng)力過程和沉積規(guī)律的最重要手段。本文在國內(nèi)外深水重力流沉積模擬實(shí)驗(yàn)相關(guān)文獻(xiàn)調(diào)研的基礎(chǔ)上,系統(tǒng)梳理重力流沉積模擬發(fā)展歷程,從重力流沉積模擬的實(shí)驗(yàn)理論、實(shí)驗(yàn)技術(shù)、關(guān)鍵應(yīng)用和最新進(jìn)展等多個(gè)方面展開論述,以期能夠推動(dòng)國內(nèi)重力流沉積模擬研究,更好的服務(wù)于深水油氣勘探。
深水重力流物理模擬
1.1深水重力流物理模擬發(fā)展歷程
重力流沉積物理模擬實(shí)驗(yàn)起源于20世紀(jì)初,至今已有100余年的歷史。根據(jù)不同時(shí)期物理模擬實(shí)驗(yàn)的主要關(guān)注點(diǎn),可以將其分為以下4個(gè)階段(圖1)。
1960年之前,沉積現(xiàn)象觀察階段。1914年,Gilbert45通過水槽實(shí)驗(yàn)觀察到了類似牽引毯(tractioncarpet)的構(gòu)造,將其稱為躍變層(saltationlayer),此外他還觀察到沉積物濃度自下而上逐步遞減的現(xiàn)象。Kuenenetal.4于1950年開展了第一次濁流實(shí)驗(yàn),認(rèn)識(shí)到濁流在深海沉積物輸運(yùn)的重要性,提出遞變層理是濁流的重要標(biāo)志,促進(jìn)了濁流理論的誕生,被譽(yù)為\"沉積學(xué)研究的一場(chǎng)革命”。
1960一1980年,沉積底形及沉積構(gòu)造研究階段。Simonsetal.49基于明渠流水實(shí)驗(yàn)討論了底床粗糙度對(duì)沖積河道底形的影響,總結(jié)了不同流態(tài)(上部流態(tài)、下部流態(tài)和過渡態(tài))的底形特征。盡管該研究目標(biāo)并非是針對(duì)深水重力流沉積,但作為首次系統(tǒng)性的水槽底形實(shí)驗(yàn)研究,激發(fā)了重力流沉積底形的水槽研究熱潮;此后,Middleton5開展了涌浪型重力流模擬實(shí)驗(yàn),將涌浪型重力流分為頭部、體部和尾部,還觀察到了高濃度濁流的粗尾遞變(coarse-tailgrading)構(gòu)造。
1980一2000年,沉積機(jī)理及沉積過程研究階段。Southard etal.52提出密度流自懸?。╝uto suspension)這一概念,討論了粒度和坡度對(duì)沉積物自懸浮能力的影響;Postmaetal.54通過水槽實(shí)驗(yàn)研究了高密度濁流的分層性,發(fā)現(xiàn)高密度濁流實(shí)際包含下部塑性層流狀的碎屑流和上部稀性濁流兩種性質(zhì)各異的流體;Knelleretal.55再現(xiàn)了濁流在封閉盆地邊緣遇到障礙物后的反射過程,提出了邊緣斜坡上內(nèi)孤立波(internalsolitarywaves)的形成機(jī)制;Mohrigetal.基于模擬實(shí)驗(yàn)證實(shí)了滑水作用(hydroplaning)的存在,為水下碎屑流和滑塊在低坡度下的長距離搬運(yùn)提供新解釋;Marretal.8利用水槽實(shí)驗(yàn)討論了黏土礦物對(duì)水下碎屑流流體演化的控制作用,研究發(fā)現(xiàn)不同類型的黏土礦物形成碎屑流的下限濃度差異較大,蒙脫土最低僅需 0.7% 的質(zhì)量分?jǐn)?shù)即可形成碎屑流,而高嶺土則需 7% 。
2000年至今,沉積一地貌動(dòng)力學(xué)定量研究階段。高精度監(jiān)測(cè)儀器的快速發(fā)展,使得深水重力流水槽實(shí)驗(yàn)逐漸轉(zhuǎn)向定量階段。Ilstadetal.2基于不同黏土含量條件下重力流模擬實(shí)驗(yàn),討論了黏土礦物含量對(duì)重力流流體類型、流速剖面及沉積厚度分布的影響;Lambetal.基于異重流沉積模擬實(shí)驗(yàn)指出平均深度的異重流流速與河流洪水流量變化相關(guān)性較差,而沉積物中的粗細(xì)顆粒一定程度上可以反映多重流動(dòng)的速度波動(dòng)和河流流量大小;deLeeuwetal.64]認(rèn)為早期堤岸沉積的形成可能是受控于平坦斜坡上的濁流自生過程,而非濁流漫溢產(chǎn)物;Pohletal.提出了新的流動(dòng)機(jī)制一一流動(dòng)松弛用以解釋海底水道一朵體過渡帶大量沉積底形的發(fā)育機(jī)制;Miramontesetal.通過水槽實(shí)驗(yàn)再現(xiàn)了重力流一等深流交互體系中重力流水道的單向遷移過程,總結(jié)了等深流流速對(duì)堤岸沉積的影響。中國方面,劉忠保等[59重現(xiàn)了陡坡帶砂質(zhì)碎屑流的形成過程,指出斜坡長度、基準(zhǔn)面的相對(duì)變化控制了碎屑流沉積體的發(fā)育規(guī)模和發(fā)育部位;鄢繼華等模擬了不同觸發(fā)條件下三角洲前緣濁積砂體的形成過程和分布規(guī)律。
1.2重力流沉積物理模擬實(shí)驗(yàn)理論與技術(shù)
1.2.1 物理模擬實(shí)驗(yàn)原理
物理模擬實(shí)驗(yàn)的關(guān)鍵是要解決模型與原型之間 相似性的問題,實(shí)驗(yàn)過程中必須遵從相似性理論。
模型與原型之間必須遵守的相似理論包括幾何相似、運(yùn)動(dòng)相似及動(dòng)力相似
幾何相似是保持實(shí)驗(yàn)?zāi)P偷膸缀涡螤?、大小與實(shí)際原型相似;同時(shí),實(shí)驗(yàn)樣品的物理和力學(xué)特性,如密度、粒度、磨圓度等,應(yīng)與原型相匹配。運(yùn)動(dòng)相似要求實(shí)驗(yàn)過程中流體運(yùn)動(dòng)狀態(tài)和實(shí)際情況相似。此外,保持模擬實(shí)驗(yàn)與實(shí)際地質(zhì)過程的時(shí)間尺度相似,有助于確保實(shí)驗(yàn)結(jié)果能夠準(zhǔn)確反映實(shí)際流體流動(dòng)行為。
動(dòng)力相似要求實(shí)驗(yàn)中液體和顆粒之間的流動(dòng)和相互作用的動(dòng)力行為與實(shí)際流體的動(dòng)力行為相似。經(jīng)典的濁流模擬實(shí)驗(yàn)用弗勞德數(shù) (Fr ,表征為流體動(dòng)量和重力之比)以及雷諾數(shù) (Re ,表征為動(dòng)量和黏性力的比值)描述濁流運(yùn)動(dòng)的動(dòng)力特征,實(shí)驗(yàn)過程中一般保證 Fr 與自然值接近, Re 高于層流的閾值以保證紊流狀態(tài)。然而,該方法忽略了對(duì)顆粒運(yùn)動(dòng)狀態(tài)的描述,不能確保顆粒主要以懸移態(tài)運(yùn)動(dòng)。deLeeuwetal.4用希爾茲數(shù) (τ*) ,湍流剪切應(yīng)力與重力的比值)和顆粒雷諾數(shù) (Rep) 描述顆粒運(yùn)動(dòng)狀態(tài),并結(jié)合重力流海底監(jiān)測(cè)和水槽實(shí)驗(yàn)資料[71-7],建立顆粒運(yùn)動(dòng)機(jī)制圖版以約束重力流沉積模擬實(shí)驗(yàn)中的動(dòng)力邊界條件,從而提高實(shí)驗(yàn)結(jié)果的可信度和可靠性(圖2)。
1.2.2 監(jiān)測(cè)技術(shù)
重力流物理模擬研究中實(shí)驗(yàn)數(shù)據(jù)的采集主要可分為三類:水下流速測(cè)量、懸移質(zhì)濃度測(cè)量和沉積地貌掃描。水下重力流的速度場(chǎng)是物理模擬實(shí)驗(yàn)最關(guān)注的參數(shù)之一。目前水槽實(shí)驗(yàn)中主要的測(cè)速方法可分為多普勒測(cè)速和粒子成像測(cè)速兩類,其中多普勒測(cè)速法依據(jù)測(cè)量原理和測(cè)量范圍又可分為激光多普勒測(cè)速(LDA)、超聲多普勒測(cè)速剖面(UDVP)和聲學(xué)多普勒測(cè)速(ADV)[8]。LDA側(cè)重于高空間分辨率的點(diǎn)測(cè)量,ADV則注重于高時(shí)間分辨率的瞬時(shí)三維點(diǎn)測(cè)量,UDVP可以實(shí)現(xiàn)垂直剖面的流速監(jiān)測(cè)。粒子成像技術(shù)(PIV)利用高速相機(jī)捕捉示蹤粒子的運(yùn)動(dòng)信息,可通過計(jì)算機(jī)技術(shù)生成高精度流場(chǎng)數(shù)據(jù),但僅適用于低濃度二維水槽或重力流沉降實(shí)驗(yàn)[78。此外,懸移質(zhì)濃度測(cè)量、沉積地貌掃描等技術(shù)也是重力流沉積物理模擬實(shí)驗(yàn)的關(guān)鍵手段,對(duì)重力流定量化研究具有重要意義。
1.2.3 國內(nèi)外重力流物理模擬實(shí)驗(yàn)室
20世紀(jì)中期以后,重力流沉積模擬迅速發(fā)展,以美國、英國、荷蘭等發(fā)達(dá)國家為代表,全球各大科研機(jī)構(gòu)相繼建立了一批重力流沉積模擬水槽實(shí)驗(yàn)平臺(tái)(表1)。國外重力流物理模擬水槽實(shí)驗(yàn)類型多樣,研究內(nèi)容廣泛,在重力流流體結(jié)構(gòu)、沉積過程、砂體分布等方面涌現(xiàn)出一批代表性成果。如杜倫大學(xué)的MatthieuCartigny團(tuán)隊(duì)對(duì)超臨界重力流底形和水躍作用進(jìn)行了深入研究[380;烏德勒支大學(xué)的JorisEggenhuisen團(tuán)隊(duì)基于水槽實(shí)驗(yàn)對(duì)濁流與深水地貌之間的作用機(jī)制提出了新的見解[6-67,74-75];Jaco Baas 團(tuán)隊(duì)在利茲大學(xué)期間專注于細(xì)粒黏性重力流物理特性和沉積特征[24.76.88];GaryParker團(tuán)隊(duì)在明尼蘇達(dá)大學(xué)期間針對(duì)濁流的沉積物輸運(yùn)過程和形態(tài)動(dòng)力學(xué)開展了一些基礎(chǔ)性研究[89-92]。
20世紀(jì)70一80年代長春地質(zhì)學(xué)院和中科院地質(zhì)所率先揭開了中國沉積物理模擬研究的序幕。隨后,由于國內(nèi)油氣勘探的需求,長江大學(xué)建立了CNPC湖盆沉積模擬實(shí)驗(yàn)室。中國石油大學(xué)(華東)、中國地質(zhì)大學(xué)(北京)等也開始各自籌建沉積物理模擬實(shí)驗(yàn)室。當(dāng)前我國的重力流沉積物理模擬研究主要關(guān)注于砂體發(fā)育特征及分布規(guī)律[59.93-95],對(duì)沉積動(dòng)力過程和地層動(dòng)力研究比較缺乏,同時(shí)相應(yīng)的監(jiān)測(cè)設(shè)備較為落后,定量化與自動(dòng)化程度較低。由于逐漸認(rèn)識(shí)到物理模擬實(shí)驗(yàn)對(duì)沉積學(xué)基礎(chǔ)理論研究的重要性,目前中國石油大學(xué)(北京)成都理工大學(xué)等高校正在籌建現(xiàn)代化沉積物理模擬實(shí)驗(yàn)平臺(tái)。
1.3重力流沉積物理模擬研究主要進(jìn)展
1.3.1物質(zhì)組成對(duì)流體性質(zhì)的影響
沉積物組成是決定流體性質(zhì)的最基本參數(shù),流體的沉積物濃度、砂泥比、黏土類型、顆粒大小等對(duì)流體性質(zhì)均有不同程度的影響。
沉積物濃度直接決定了重力流流體類型,隨著沉積物濃度的降低,碎屑流總是趨于向濁流轉(zhuǎn)化。一般認(rèn)為,高密度濁流的體積濃度應(yīng)大于 6% 或流體密度大于 1.1g/mL[46] ;當(dāng)沉積物體積濃度達(dá)到 25% 時(shí),流體紊流受到完全抑制最終轉(zhuǎn)化為碎屑流2。沉積物顆粒大小對(duì)流體類型與運(yùn)動(dòng)狀態(tài)同樣具有重要影響。Elerianetal.85發(fā)現(xiàn)較大的顆粒粒徑會(huì)顯著降低濁流的鋒面速度和搬運(yùn)距離,而顆粒濃度一定程度上可以中和顆粒尺寸對(duì)濁流運(yùn)動(dòng)的影響,濁流濃度足夠高時(shí),顆粒尺寸對(duì)濁流運(yùn)動(dòng)的影響已經(jīng)微乎其微。此外,粗顆粒相較于細(xì)顆粒更易形成碎屑流,且搬運(yùn)距離更遠(yuǎn)[59]。黏土礦物和有機(jī)質(zhì)作為流體內(nèi)聚力的直接來源,能夠有效的抑制濁流的紊流性質(zhì),使流體向?qū)恿餍再|(zhì)的碎屑流轉(zhuǎn)變[23]。最新研究發(fā)現(xiàn),濁流與碎屑流之間存在著流體性質(zhì)介于紊流和層流之間的過渡型流體。隨著黏土礦物的增加,濁流會(huì)逐步轉(zhuǎn)化為紊流增強(qiáng)過渡流、上過渡塞流、準(zhǔn)層狀塞流等過渡型流體,并伴隨獨(dú)特的底床類型[97-98]。然而,不同類型的黏土礦物由于物質(zhì)組成和分子結(jié)構(gòu)的差異,其吸水膨脹能力顯著不同,蒙脫土的親水性可達(dá)高嶺石的60倍9。水槽實(shí)驗(yàn)指出蒙脫土最低僅需 0.7% 的質(zhì)量分?jǐn)?shù)即可形成碎屑流,而高嶺土則需7% 的質(zhì)量分?jǐn)?shù)[58]。
1.3.2沉積地貌單元與重力流交互
經(jīng)典的海底扇模式由深水水道、堤岸、朵體以及水道一朵體過渡帶等組成[25.100]。重力流通過其強(qiáng)大的侵蝕搬運(yùn)能力塑造不同的沉積單元,沉積單元又因其內(nèi)部的形態(tài)差異反作用于流體運(yùn)動(dòng)過程,兩者之間的相互作用是重力流研究的重點(diǎn)內(nèi)容。
深水水道是深海沉積物輸送的主要途徑[],其內(nèi)部充填物記錄了源區(qū)古氣候變化[2],同時(shí)也是良好的油氣儲(chǔ)層[03]。Keeviletal.[4通過彎曲水道模擬實(shí)驗(yàn)指出深水水道的次級(jí)流動(dòng)對(duì)沉積物分配具有重要影響,深水水道處的次級(jí)流動(dòng)有利于堤岸外側(cè)粗粒沉積物堆積。Kaneetal.認(rèn)為深水水道中的大型不平衡流動(dòng)導(dǎo)致水道外彎處沉積大量泥沙,使水道短暫變直,進(jìn)而增強(qiáng)了深水水道的平面穩(wěn)定性,使其不易像陸上河道頻繁發(fā)生截彎和決口(圖3a)。
水道一朵體過渡帶是連接深水水道和深海盆地的過渡性區(qū)域。當(dāng)濁流離開水道進(jìn)入深海盆地,流體失去水道的側(cè)向限制發(fā)生橫向擴(kuò)散,進(jìn)而增加了水體的整體摩擦,導(dǎo)致流體減速和懸浮沉積物沉降,并在水道末端堆積形成朵體復(fù)合體。然而,多地海底觀測(cè)在水道一朵體過渡帶發(fā)現(xiàn)的沖刷場(chǎng)(scourfield)構(gòu)造[105-108],表明水道—朵體過渡帶可能并非以沉積作用為主。Komar[0]認(rèn)為沖刷場(chǎng)的形成是由于濁流失去限制性后,流體從超臨界流向亞臨界流轉(zhuǎn)變,伴隨而來的水躍作用增強(qiáng)了流體的侵蝕能力。Pohletal.在室內(nèi)水槽實(shí)驗(yàn)中并未發(fā)現(xiàn)水道一朵體過渡帶的水躍作用及其伴生的流厚突然增加現(xiàn)象[。結(jié)合實(shí)驗(yàn)結(jié)果,Pohletal.提出流動(dòng)松弛機(jī)制用來解釋沖刷場(chǎng)現(xiàn)象(圖3b)。當(dāng)濁流離開水道后,流體失去橫向限制向兩側(cè)擴(kuò)散,流速整體降低,但流體厚度減薄的同時(shí)也導(dǎo)致濁流頭部最大流速深度相應(yīng)降低,進(jìn)而導(dǎo)致靠近底床的流體剪切速度增大(圖3c),由此增強(qiáng)了濁流的基底剪切能力,有利于沖刷場(chǎng)的形成。
1.3.3重力流與等深流交互
深水環(huán)境主要發(fā)育重力流和等深流兩種沉積物輸送機(jī)制。重力流是一種瞬時(shí)、高能的事件性流體,而等深流則是受地球自轉(zhuǎn)作用力影響而產(chǎn)生的持續(xù)存在的低能流體。等深流可以改造先存或正在沉積的重力流水道,形成等深流一重力流混合沉積體系[110-12]
Miramontesetal.通過水槽實(shí)驗(yàn)再現(xiàn)了重力流水道的單向遷移模式。當(dāng)濁流和等深流同時(shí)處于活躍時(shí)期,一定強(qiáng)度的等深流可以使?jié)崃靼l(fā)生偏移和不對(duì)稱溢出,在盆地下游形成不對(duì)稱的堤岸系統(tǒng)。
同時(shí),等深流流速對(duì)堤岸發(fā)育程度具有重要影響,流速越快,上游堤岸沉積越厚,下游堤岸沉積越寬,并導(dǎo)致水道向上游遷移(圖4a\~d)。Fedeleetal.3發(fā)現(xiàn)重力流水道的遷移方向取決于等深流流體底部厚度與重力流水道深度的相互關(guān)系。當(dāng)?shù)壬盍鞯撞窟吔鐚雍穸冗h(yuǎn)小于重力流水道深度時(shí),等深流會(huì)完全落入重力流水道,在水道上游處,流體加速下滑,造成侵蝕;下游處,流體減速爬升,并逐漸沉降,由此導(dǎo)致了重力流水道沿等深流流向反向遷移(圖4e);當(dāng)?shù)壬盍鞯撞窟吔鐚雍穸冉咏虼笥谥亓α魉郎疃葧r(shí),等深流底部邊界層會(huì)在水道上游發(fā)生分離,等深流攜帶的物質(zhì)就此沉降,流經(jīng)水道下游時(shí),底部邊界層與上部等深流附著并收縮,并可能促進(jìn)沉積物的改造和侵蝕,這種情況下重力流水道順著等深流流動(dòng)方向遷移(類似于沙丘遷移)圖4f)。
1.3.4超臨界濁流及其底形
超臨界濁流是指密度弗勞德數(shù) (FrD) 大于1的,可通過水躍作用轉(zhuǎn)化為亞臨界流的深水重力流[09,11415]。研究表明,超臨界濁流與海底峽谷[80.116]深水水道[117-118]、周期階坎[11]等海底地貌的形成密切相關(guān)。然而,由于其強(qiáng)大的侵蝕能力,超臨界濁流留下的地質(zhì)記錄相對(duì)較少[63],導(dǎo)致人們對(duì)其理解仍然有限。
Sequeiros基于歷年的水槽實(shí)驗(yàn)和現(xiàn)場(chǎng)觀測(cè)數(shù)據(jù)指出當(dāng)?shù)状财露却笥?0.5° 時(shí),濁流就具備了轉(zhuǎn)化成超臨界流的條件。隨著弗勞德數(shù)的增大,超臨界流底形依次向著逆行沙丘、不穩(wěn)定逆行沙丘、沖坑和沖槽、旋回階坎轉(zhuǎn)變[]。其中逆行沙丘和旋回階坎作為該過程的兩大穩(wěn)定單元,其沉積記錄在海底觀測(cè)中多有發(fā)現(xiàn)。水躍(hydraulic jump)作用是超臨界流向亞臨界流的突然過渡,其特征是流體厚度急劇增加,流速下降,流體能量大量損失。Cartignyetal.提出在不考慮流體或沉積物夾帶的前提下,用共軛深度比(水躍前超臨界流厚度/水躍后亞臨界流厚度)來衡量水躍強(qiáng)度等級(jí),將其分為波狀水躍、弱水躍、振蕩水躍、穩(wěn)定水躍、強(qiáng)水躍五類(圖5)。水躍作用的內(nèi)部結(jié)構(gòu)受控于共軛深度比,共軛深度比越大,水躍過程中的能量損失越大。
Onoetal.通過水槽實(shí)驗(yàn)研究了涌浪型濁流中水躍作用對(duì)底床形態(tài)、粒度分選的影響。單期涌浪型濁流可以在一個(gè)旋回階坎的迎流面下部形成多次沖刷,濁流的頭部、體部和尾部可以在迎流面不同位置產(chǎn)生水躍,從而形成多期沖刷充填體,隨著旋回階坎向上游逐漸遷移,同時(shí)產(chǎn)生向上變細(xì)的沉積序列。該研究為海底旋回階坎中含多重沖刷特征、向上變細(xì)的濁積巖序列[120提供了一種新的成因解釋。
2 深水重力流數(shù)值模擬
深水重力流數(shù)值模擬是通過數(shù)學(xué)方法來研究和預(yù)測(cè)重力流運(yùn)動(dòng)行為[121]。其原理基于牛頓力學(xué)和流體力學(xué)的基本方程(包括質(zhì)量守恒方程、動(dòng)量守恒方程和能量守恒方程)8。重力流數(shù)值模擬能夠在多個(gè)尺度上再現(xiàn)重力流沉積演化過程,明確重力流流體動(dòng)力參數(shù)的時(shí)空變化,還可以預(yù)測(cè)海底扇發(fā)育模式與構(gòu)型樣式,指導(dǎo)深水油氣勘探。由于高濃度流體需要考慮顆粒之間的碰撞運(yùn)動(dòng),極大程度上增加了運(yùn)算的工作量,目前深水重力流數(shù)值模擬研究主要集中在低密度濁流領(lǐng)域。
2.1重力流數(shù)值模擬發(fā)展歷程
1980年之前,經(jīng)驗(yàn)公式和簡化模型階段。1845年,用于描述黏性不可壓縮流體動(dòng)量守恒的納維一斯托克斯(Navier-Stokes,N-S)方程就此問世。雖然N-S方程理論上可以描述湍流在三維時(shí)空內(nèi)的全部流動(dòng)細(xì)節(jié),但由于湍流瞬時(shí)運(yùn)動(dòng)的極端復(fù)雜性,基于N-S方程的直接數(shù)值模擬方法仍然極具挑戰(zhàn)性。為了便于計(jì)算機(jī)求解,科學(xué)家們開始提出簡化的計(jì)算模型。1952年,Kuenen首次運(yùn)用切奇公式評(píng)估了1929年紐芬蘭大淺灘的濁流事件。隨后,Ellisonetal.4提出了基于N-S方程簡化的深度平均模型(Depth-averagedmoded),該模型假設(shè)流體在垂直方向上的性質(zhì)變化不顯著,允許通過垂直積分來計(jì)算流體動(dòng)力參數(shù)。Chuetal.選取深度平均模型,并根據(jù)弗勞德數(shù)的變化,將濁流的運(yùn)動(dòng)過程分為流動(dòng)建立、均勻流動(dòng)、水力跳躍和流動(dòng)衰減4個(gè)階段?;谄骄疃壤碚摚琍arkeretal.53推導(dǎo)出描述濁流動(dòng)力學(xué)的層平均運(yùn)動(dòng)方程,再現(xiàn)了濁流的自加速效應(yīng);此后,一些研究者開始將盒子模型[56.122]用于重力流數(shù)值模擬,并取得了較好的應(yīng)用效果。事實(shí)上,濁流存在顯著的分層結(jié)構(gòu)54,平均深度模型只能描述濁流平面上的運(yùn)動(dòng)過程,而忽略了垂直方向上的運(yùn)動(dòng),限制了計(jì)算結(jié)果的適用性。
1980—2000年,二維混合模型階段。1980年起重力流數(shù)值模擬理論迅速發(fā)展,形成了以雷諾平均數(shù)值模擬(ReynoldsAverage Navier-Stockes,RANS)、大渦模擬(LargeEddySimulation,LES)、直接數(shù)值模擬(DirectNumericalSimulation,DNS)為主的3類模擬方法。其中RANS的核心思想是應(yīng)用湍流統(tǒng)計(jì)理論,對(duì)N-S方程進(jìn)行時(shí)間平均,從而計(jì)算得到時(shí)均流場(chǎng)數(shù)據(jù)[123-124]。由于雷諾平均方程并不封閉,需要引入雷諾應(yīng)力的平均模型[83]。該法可以提供運(yùn)動(dòng)的平均物理量,滿足大多數(shù)工程計(jì)算需求,但在處理強(qiáng)剪切(靠近墻壁或障礙物)以及低至中等雷諾數(shù)流動(dòng)的區(qū)域時(shí)計(jì)算效果不佳[25-126]。大渦模擬通過特定的濾波函數(shù)將湍流的瞬時(shí)運(yùn)動(dòng)分解為大尺度運(yùn)動(dòng)和小尺度脈動(dòng),大尺度運(yùn)動(dòng)通過N-S方程直接求解,小尺度脈動(dòng)通過特定的湍流模型進(jìn)行簡化計(jì)算[12]。該方法能夠得到流體瞬時(shí)運(yùn)動(dòng)的脈動(dòng)量,但其計(jì)算量也遠(yuǎn)高于RANS法[128]。此外,為了獲取更高精度的模擬結(jié)果,一些研究者開始采用直接數(shù)值模擬求解湍流方程的全部參數(shù),但由于湍流運(yùn)動(dòng)的復(fù)雜性,需要極高的計(jì)算資源,且不適用于較高雷諾數(shù)的濁流運(yùn)動(dòng)模擬[69,129]
2000年至今,高分辨率三維數(shù)值模擬階段。隨著計(jì)算機(jī)處理能力的顯著提升,科學(xué)家可以進(jìn)行高分辨率的三維重力流數(shù)值模擬。這使得對(duì)復(fù)雜地形、多粒度分布以及流體一固體相互作用等的高精度模擬成為可能。如Howlettetal.[3o]利用數(shù)值模擬技術(shù)研究非限制性濁流對(duì)海底褶皺地貌的響應(yīng)機(jī)制,觀測(cè)到了濁流的開爾文一亥姆霍茲不穩(wěn)定性和水躍現(xiàn)象;Abdetal.3模擬了尼日爾三角洲大陸斜坡的海底濁流運(yùn)動(dòng),預(yù)測(cè)了濁流演化過程和不同粒級(jí)顆粒的空間分布。此外,機(jī)器學(xué)習(xí)和人工智能技術(shù)被逐漸引入到重力流數(shù)值模擬中[132-134]。這些技術(shù)有助于優(yōu)化模型參數(shù),識(shí)別模式,甚至預(yù)測(cè)未知條件下的沉積過程。
2.2 重力流數(shù)值模擬平臺(tái)
重力流數(shù)值模擬起源于20世紀(jì)中期48],作為一種重要的工程和科學(xué)研究手段,被廣泛用于海洋工程災(zāi)害評(píng)估[135]、河流泥沙運(yùn)移[136-137]、油氣勘探[138-139]等領(lǐng)域。根據(jù)不同的應(yīng)用需求和模擬目標(biāo),眾多研究機(jī)構(gòu)或商業(yè)公司開發(fā)了各具特色的重力流數(shù)值模擬平臺(tái)。
Flow-3D是一款由美國FlowScience公司開發(fā)的商業(yè)計(jì)算流體動(dòng)力學(xué)(ComputationalFluidDynamics,CFD)軟件。它基于有限體積法建立三維模型,采用多相漂移通量流法預(yù)測(cè)濁流運(yùn)動(dòng)。Flow-3D將泥沙擴(kuò)散視為連續(xù)相,計(jì)算流體空間體積濃度。Flow-3D可以監(jiān)測(cè)濁流在時(shí)間和空間上的連續(xù)流動(dòng)特征,包括流動(dòng)密度、沉積物濃度、粒度離析、空間平均速度場(chǎng)、內(nèi)部剪切應(yīng)變率(湍流強(qiáng)度)動(dòng)態(tài)黏度和底部剪切應(yīng)力等[140]
Fluent軟件起源于謝菲爾德大學(xué)的Boysanetal.4開發(fā)的CFD代碼,后被ANSYS公司收購,并整合為ANSYSFluent。目前,F(xiàn)luent已成為應(yīng)用最為廣泛的商業(yè)CFD軟件之一。Fluent軟件基于有限體積法,將流動(dòng)區(qū)域離散化為有限體積,并通過求解連續(xù)方程、動(dòng)量方程和能量方程等基本方程來模擬濁流的流動(dòng)和傳輸過程。Fluent軟件支持GPU并行計(jì)算,能夠顯著降低濁流數(shù)值模擬的計(jì)算時(shí)間[142]。
Delft3D是代爾夫特理工大學(xué)開發(fā)的開源流體動(dòng)力模擬軟件。該軟件基于泥沙水動(dòng)力方程,可以實(shí)現(xiàn)沉積物輸運(yùn)和地貌演變的三維模擬。Delft3D側(cè)重于河流、三角洲、浪控等的沉積模擬,同時(shí)也可用于預(yù)測(cè)深水重力流的運(yùn)動(dòng)過程和水動(dòng)力特征[43-144]。
CATS(TheCellularAutomataforTurbiditeSystems)是由法國石油研究院開發(fā)的一款用于模擬濁積巖儲(chǔ)層的結(jié)構(gòu)和空間分布的工業(yè)軟件。該軟件基于勢(shì)能、動(dòng)能平衡和擴(kuò)散原理,以臨近單元(元細(xì)胞自動(dòng)機(jī))之間的局部規(guī)則對(duì)給定地形的濁流流動(dòng)進(jìn)行建模。CATS軟件無需求解復(fù)雜的水動(dòng)力方程,計(jì)算量小,模擬時(shí)間短,對(duì)濁積體內(nèi)部結(jié)構(gòu)刻畫效果較好[138]
Sedsim(Sedsim Forward Stratigraphic Modelling)軟件是由斯坦福大學(xué)在20世紀(jì)80年代開發(fā)的三維地層正演模擬軟件。Sedsim軟件基于簡化的N-S水動(dòng)力學(xué)方程,能夠在地質(zhì)和工程時(shí)間尺度上模擬地層或盆地形成過程。Sedsim軟件可以模擬構(gòu)造、海平面變化、氣候等因素影響下的多類型沉積過程,廣泛應(yīng)用于油氣勘探預(yù)測(cè)中[45](表2)。
2.3重力流數(shù)值模擬軟件研究主要進(jìn)展
2.3.1重力流流體結(jié)構(gòu)和水動(dòng)力參數(shù)
三維數(shù)值模擬可從不同尺度、不同角度系統(tǒng)對(duì)比分析濁流的動(dòng)力學(xué)特征。模擬過程中可以對(duì)關(guān)鍵參數(shù)進(jìn)行連續(xù)監(jiān)控,分析其變化所伴隨的沉積響應(yīng)。Salinasetal.基于重力流數(shù)值模擬發(fā)現(xiàn),超臨界濁流具有近床層和界面層組成的雙層結(jié)構(gòu),兩層流體都表現(xiàn)為高度湍流特性,垂向最大流速出現(xiàn)在近底床層和界面層的交界處(圖 6a,b) ;相比之下,亞臨界濁流(體部)自下而上由近床層、中間層、界面層組成。其中僅近床層具有高度湍流性質(zhì),該層沉積物具有良好的混合,向上流體雷諾數(shù)減低,至界面層時(shí)已與環(huán)境水體層出現(xiàn)明顯的光滑界線(圖6c,d)。研究表明,亞臨界流體的三層結(jié)構(gòu)可能與海底水道中濁流的超長體部的形成有關(guān)[68]。
密度弗雷德數(shù)是區(qū)分超臨界濁流與亞臨界濁流的關(guān)鍵參數(shù),通常認(rèn)為超臨界濁流的密度弗勞德數(shù)大于1,亞臨界濁流的密度弗勞德數(shù)小于1。Huangetal.[14提出重力流的臨界密度弗雷德數(shù)不一定是一個(gè)恒定值。根據(jù)周圍流體的夾帶程度和重力流的密度變化,重力流的臨界密度弗雷德數(shù)存在3種情況,大于1,不存在或小于1。此外,傳統(tǒng)觀點(diǎn)認(rèn)為異重流入水后,沉積物顆粒的不斷沉降會(huì)降低異重流的密度,導(dǎo)致異重流的搬運(yùn)距離較短。然而最新研究顯示,沉積物顆粒一鹽的擴(kuò)散率差異可以使異重流轉(zhuǎn)為含鹽濁流,異重流損失沉積物的同時(shí)會(huì)從環(huán)境水體(海水)中吸收相應(yīng)的鹽分,從而維持異重流的密度穩(wěn)定,并能夠搬運(yùn)至相當(dāng)長的距離[147]。
2.3.2 復(fù)雜地貌下重力流的沉積過程及分布特征
數(shù)值模擬可以提取地下地貌數(shù)據(jù),構(gòu)建多樣化的地質(zhì)模型,再現(xiàn)深水地貌與重力流沉積的交互過程,并揭示有利沉積體的分布規(guī)律。褶皺和斷層作為擠壓構(gòu)造背景下產(chǎn)生的典型地貌,廣泛存在于陸相斷陷湖盆和深海構(gòu)造活躍帶,深刻控制著海底沉積物的運(yùn)輸和沉積[34]。Howlettetal.[30通過數(shù)值模擬總結(jié)了非限制性濁流對(duì)褶皺地貌的響應(yīng)模式。根據(jù)褶皺地貌與濁流的相對(duì)大小,可分為大褶皺小濁流和小褶皺大濁流兩種模式(圖7a,b)。當(dāng)褶皺地貌遠(yuǎn)小于濁流體積時(shí),濁流主體能夠越至褶皺后翼,發(fā)生水躍作用導(dǎo)致濁流減速、顆粒沉降,在褶皺后翼前緣、后翼反斜坡、褶皺前翼形成明顯的沉積區(qū);當(dāng)褶皺地貌遠(yuǎn)大于濁流體積時(shí),濁流主體在褶皺前翼減速沉積,少量低密度流體越過褶皺后翼并發(fā)生水躍作用。Geetal.通過數(shù)值模擬揭示了真實(shí)尺度下濁流流經(jīng)正斷層地貌時(shí)的沉積過程和沉積模式(圖7c\~e)。研究發(fā)現(xiàn)該模式與傳統(tǒng)的斜坡扇模型2存在較大差異:受斷層地貌影響,砂體成斑狀分布,自上而下可分為四個(gè)主要沉積區(qū):濁流出口堆積區(qū)、下盤邊緣堆積區(qū)、斷層頂部堆積區(qū)以及上盤頂部堆積區(qū)。
在濁流的沉積過程中,開爾文一亥姆霍茲界面的不穩(wěn)定性引起了流速大小和泥沙濃度的三維波動(dòng),進(jìn)而調(diào)節(jié)了沉積物的分配。
2.3.3海底扇發(fā)育模式及形態(tài)動(dòng)力學(xué)研究
海底扇的形態(tài)很大程度上取決于在其表面移動(dòng)的水道動(dòng)力學(xué)。Wahabetal.通過數(shù)值模擬歸納了密度弗勞德數(shù) (FrD) 和勞斯數(shù) (p) 控制下的海底扇3種發(fā)育模式。類似于剛果現(xiàn)代扎伊爾扇體系148(圖8a),亞臨界海底扇 (FrDlt;1,plt;0.055 以內(nèi)部不對(duì)稱的分支水道為特征,該模式中砂質(zhì)沉積物主要富集在水道內(nèi)部,粉砂一泥質(zhì)沉積物發(fā)育在堤岸、朵體和外扇部位(圖8b,c);墨西哥灣第四紀(jì)東部斷陷盆地IV號(hào)海底扇屬臨界海底扇 (FrD=1,plt;0.101 模式(圖8d),該模式內(nèi)部以自生的低彎度水道為特征,水道兩側(cè)發(fā)育明顯的堤岸沉積,沉積物以過路作用為主,砂質(zhì)沉積物發(fā)育在水道、朵體和遠(yuǎn)端堤岸,粉砂及泥質(zhì)沉積物主要發(fā)育在遠(yuǎn)端扇(圖8e,f;超臨界海底扇(FrD=1.17,p=0.22) 內(nèi)部發(fā)育單一的自生低彎度主水道。流體厚度的增加和湍流動(dòng)能的損失導(dǎo)致沉積物以旋回坎的形式在河道內(nèi)部向上游遷移。水道內(nèi)部的高剪切應(yīng)力抑制細(xì)粒沉積物沉降,海底扇以砂質(zhì)沉積物為主,整體呈長條狀,類似于現(xiàn)代斯瓦米什海底扇(圖 8g~i)[149]
3 討論與展望
(1)沉積模擬的局限性。沉積物理模擬基于相似性原理,需要滿足幾何相似、運(yùn)動(dòng)相似和動(dòng)力相似原則。實(shí)驗(yàn)?zāi)P屯ǔ0匆欢ū壤M(jìn)行縮放,但某些參數(shù)(顆粒粒度、深海高壓等)難以完全模擬現(xiàn)實(shí)世界條件。重力流的運(yùn)動(dòng)和動(dòng)力相似一般通過弗勞德(a,b)大褶皺小濁流沉積模式與小褶皺大濁流沉積模式(據(jù)文獻(xiàn)[130]修改); (c~e) 正斷層地貌下濁流演化過程、主要沉積區(qū)域及愛爾蘭西部裂谷盆地早白堊世海底斷裂帶均方根屬性圖(據(jù)文獻(xiàn)[65]修改)
數(shù)、雷諾數(shù)和希爾茲數(shù)等無量綱參數(shù)來約束。目前實(shí)驗(yàn)中僅能保持單一參數(shù)(弗勞德數(shù)或希爾茲數(shù))與真實(shí)值接近,而雷諾數(shù)高于紊流界限值即可。此外,重力流的自加速、卷吸等特性需要一定的時(shí)間和空間累積才能夠體現(xiàn)出來。數(shù)值模擬雖能實(shí)現(xiàn)與真實(shí)模型一致的時(shí)空尺度,但由于納維一斯托克斯公式的復(fù)雜性,計(jì)算精度和運(yùn)算時(shí)長往往成反比,一個(gè)高精度模型計(jì)算時(shí)長高達(dá)上百萬核時(shí)[68]。同時(shí),目前的重力流數(shù)值模擬對(duì)高濃度顆粒運(yùn)動(dòng)以及濁流的底床侵蝕作用模擬效果也不盡如人意[68]
(2)多學(xué)科交互。目前重力流研究正邁向定量化的重要階段,除了傳統(tǒng)的野外露頭、地下資料、海底監(jiān)測(cè),沉積物理模擬和數(shù)值模擬已成為重力流定量研究的重要手段。沉積物理模擬能夠有效刻畫重力流沉積過程和動(dòng)力學(xué)特征,同時(shí)要求研究者兼具地質(zhì)學(xué)和流體動(dòng)力學(xué)知識(shí)背景,以便分析流體水動(dòng)力現(xiàn)象并總結(jié)地質(zhì)規(guī)律。盡管當(dāng)前的重力流數(shù)值模擬軟件已相對(duì)成熟,但仍需用戶具備一定的編程能力,以根據(jù)地質(zhì)背景開發(fā)新功能。因此,未來重力流沉積模擬需要地質(zhì)學(xué)、水力學(xué)和計(jì)算機(jī)科學(xué)等多學(xué)科研究者加強(qiáng)合作,地質(zhì)資料和過程模擬相結(jié)合,推動(dòng)沉積學(xué)理論的發(fā)展。
(3)深水油氣開發(fā)。深水重力流沉積形成了廣泛分布的重力流砂巖,并蘊(yùn)含著豐富的油氣資源。傳統(tǒng)的沉積地質(zhì)研究通過露頭、巖心和地震等靜態(tài)資料對(duì)重力流形成機(jī)制、沉積特征和發(fā)育模式等方面有了宏觀的理解,但在定量研究重力流沉積過程和流體轉(zhuǎn)化方面尚顯不足。流體搬運(yùn)過程的差異將直接導(dǎo)致沉積充填樣式、砂體展布及疊置樣式等沉積結(jié)構(gòu)的不同。借助沉積模擬的手段可以加深重力流沉積過程和分布規(guī)律的理解,預(yù)測(cè)有利沉積體的分布規(guī)模和空間組合關(guān)系,為深水油氣勘探提供理論支持。
(4)海洋地質(zhì)災(zāi)害。海底滑坡是海底沉積物受多種誘發(fā)因素發(fā)生大范圍移動(dòng)的地質(zhì)現(xiàn)象[150],其發(fā)展演化過程包括滑動(dòng)、滑塌、碎屑流、濁流四個(gè)階段[151]。隨著世界海洋能源開發(fā)不斷向深海推進(jìn),以海底滑坡為代表的海洋地質(zhì)災(zāi)害正對(duì)水下基礎(chǔ)設(shè)施產(chǎn)生重大威脅。自前關(guān)于海底滑坡的相關(guān)研究主要集中在海底滑坡形成機(jī)制、演化過程和對(duì)水下設(shè)施沖擊評(píng)估3個(gè)方面。借助沉積物理模擬手段,可以控制初始邊界條件,開展不同觸發(fā)機(jī)制條件下的海底滑坡模擬實(shí)驗(yàn),制定斜坡失穩(wěn)評(píng)價(jià)標(biāo)準(zhǔn);從海底滑坡發(fā)展規(guī)律人手,探究不同地形作用下滑坡沖出距離、堆積寬度、堆積厚度等,建立海底滑坡運(yùn)動(dòng)演化模型;最后通過數(shù)值模擬開展海底滑坡沖擊水下管線實(shí)驗(yàn),建立滑坡沖擊力預(yù)測(cè)公式,評(píng)估滑坡破壞性。
參考文獻(xiàn)(References)
[1]MeiburgE,KnellerB.Turbidity currentsand their deposits[J] AnnualReviewofFluidMechanics,2010,42:135-156.
[2] WellsMG,DorrellRM.Turbulence processeswithin turbidity currents[J].AnnualReviewofFluidMechanics,2021,53:59-83.
[3] CossuR,F(xiàn)orrestAL,Roop HA,etal. Seasonal variability in tur biditycurrents in LakeOhau,New Zealand,and their influence on sedimentation[J]. Marine and Freshwater Research, 2016,67(11): 1725-1739.
[4]Talling PJ,Cartigny MJB,Pope E,et al.Detailed monitoring revealsthe nature of submarine turbidity currents[J].Nature ReviewsEarthamp;Environment,2023,4(9):642-658.
[5]溫志新,王建君,王兆明,等.世界深水油氣勘探形勢(shì)分析與思 考[J].石油勘探與開發(fā),2023,50(5):924-936.[WenZhixin, WangJianjun,Wang Zhaoming,etal.Analysisof theworld deepwater oil and gas exploration situation[J].Petroleum Exploration and Development,2023,50(5): 924-936.]
[6]Piper D JW, Cochonat P,Morrison ML. The sequence of events around the epicentre of the 1929 Grand Banks earthquake: Initiation of debris flowsand turbidity current inferred from sidescan sonar[J].Sedimentology,1999,46(1): 79-97.
[7]CarterL,Gavey R,Talling PJ,etal.Insights into submarine geohazards from breaks in subsea telecommunication cables[J]. Oceanography,2014,27(2): 58-67.
[8]Galy V,F(xiàn)rance-Lanord C,Beyssac O,et al. Efficient organic carbon burial in the Bengal fan sustained by the Himalayan erosional system[J]. Nature,2007,450(7168): 407-410.
[9]Talling PJ,Hage S,Baker ML,et al.The global turbidity current pumpanditsimplicationsfororganic carboncycling[J].Annual Review ofMarine Science,2024,16:105-133.
[10]Jutzeler M,Manga M,White JDL,etal.Submarine deposits from pumiceous pyroclastic density currents traveling over Water:An outstanding example from offshore Montserrat (IODP 340)[J].Geological Society of America Bulletin,2017,129(3/ 4): 392-414.
[11]MountjoyJJ, Howarth JD,Orpin AR,et al.Earthquakes drive large-scale submarine canyon development and sediment supply to deep-ocean basins[J]. Science Advances,2018,4(3): eaar3748.
[12]楊劍萍,黃雅睿,盧惠東,等.東營凹陷營11北地區(qū)沙三中亞 段重力流觸發(fā)機(jī)制[J].中國石油大學(xué)學(xué)報(bào)(自然科學(xué)版), 2021,45(4):1-11.[Yang Jianping,Huang Yarui,Lu Huidong, et al.Triggering mechanism of gravity flow sandbodies of Middle Es member in the north of well Ying 11,Dongying Depression[J].Journal of China University of Petroleum (Edition of Natural Science),2021,45(4): 1-11.]
[13]Puig P, Ogston A S,Mullenbach B L,et al.Storm-induced sediment gravity flows at the head of the Eel submarine canyon, northern California margin[J]. Journal of Geophysical Research: Oceans,2004,109(C3): C03019.
[14]SequeirosOE,Bolla Pitaluga M,F(xiàn)rascati A,etal.How typhoons trigger turbidity currents in submarine canyons[J]. Scientific Reports,2019,9(1): 9220.
[15]Mulder T,Migeon S,Savoye B,et al.Twentieth century floods recorded inthedeep Mediterranean sediments[J].Geology, 2001,29(11): 1011-1014.
[16]Xian B Z,Wang JH, GongCL,et al. Classification and sedimentary characteristics of lacustrine hyperpycnal channels: Triassic outcrops in the south Ordos Basin, central China[J]. Sedimentary Geology,2018,368: 68-82.
[17]Chen P, XianB Z,LiMJ, et al.A giant lacustrine flood-related turbidite system in the Triasic Ordos Basin, China: Sedimentary processes anddepositional architecture[J].Sedimentology, 2021,68(7): 3279-3306.
[18]Heijnen MS,Mienis F, Gates AR,et al.Challenging the highstand-dormant paradigm for land-detached submarine canyons [J].Nature Communications,2022,13(1):3448.
[19]Hage S,Cartigny MJB, SumnerEJ,et al.Direct monitoring revealsinitiationofturbiditycurrents fromextremelydiluteriver plumes[J]. Geophysical Research Letters,2019,46(20):11310- 11320.
[20]Forel FA.Le ravin sous-lacustre du Rhone dans le lac Léman [J].Bulltin de La Societé Vaudoise des Sciences Naturelles, 1888,23: 85-107.
[21]Middleton G V, Hampton M A. Sediment gravity flows: Mechanics of flow and deposition[M]//Middleton G V,Bouma AH. Turbidites and deep water sedimentation. Anaheim:SEPM, 1973:1-38.
[22]Lowe D R. Sediment gravity flows: I, Depositional models with special reference to the deposits of high-density turbidity currents[J]. Journal of Sedimentary Research,1982,52(1): 279-297.
[23]TallingP J,Masson DG, Sumner E J, et al. Subaqueous sediment density flows: Depositional processes and deposit types[J]. Sedimentology,2012,59(7):1937-2003.
[24]Baas J H,Best JL.Turbulence modulation in clay-rich sediment-laden flows and some implications for sediment deposition [J].Journal of Sedimentary Research,2002,72(3):336-340.
[25]Walker R G. Deep-water sandstone facies and ancient submarinefans:Models for exploration for stratigraphic traps[J]. AAPG Bulletin,1978, 62(6): 932-966.
[26]Shanmugam G.5O years of the turbidite paradigm (1950s1990s):Deep-water processes and facies models-a critical perspective[J]. Marine and Petroleum Geology,2000,17(2): 285-342.
[27]楊仁超,李作福,張學(xué)才,等.異重流沉積研究進(jìn)展與展望[J]. 沉積學(xué)報(bào),2023,41(6):1917-1933.[YangRenchao,Li Zuofu, Zhang Xuecai, et al. Advances and perspectives in the study of hyperpycnal flow deposition[J]. Acta Sedimentologica Sinica, 2023,41(6): 1917-1933.]
[28]陳軒,陶鑫,覃建華,等.準(zhǔn)噶爾盆地吉木薩爾凹陷及周緣二 疊系蘆草溝組異重流沉積[J].石油與天然氣地質(zhì),2023,44 (6):1530-1545.[Chen Xuan,Tao Xin,Qin Jianhua, et al.Hyperpycnal flow deposits of the Permian Lucaogou Formation in theJimusaer Sag and its peripheries,Junggar Basin[J].Oilamp; Gas Geology,2023,44(6): 1530-1545.]
[29]劉海寧,韓宏偉,操應(yīng)長,等.東營凹陷東坡古近系沙三中亞 段異重流沉積特征與沉積模式[J].中國石油大學(xué)學(xué)報(bào)(自然科 學(xué)版),2022,46(1):13-22.[Liu Haining,Han Hongwei, Cao Yingchang,et al. Sedimentary characteristics and depositional model of hyperpycnites in the middle of the third member of Paleogene Shahejie Formation in the east slope of Dongying Sag [J].Journal of China University of Petroleum (Edition of Natural Science),2022,46(1): 13-22.]
[30]LiuJP, Xian B Z, Wang JH,et al. Sedimentary architecture ofa sub-lacustrine debris fan:Eocene Dongying Depression,Bohai Bay Basin,east China[J]. Sedimentary Geology,2017,362: 66-82.
[31]吳千然,鮮本忠,高先志,等.強(qiáng)制湖退期湖底扇沉積構(gòu)型的 多樣性與砂體分布特征:以渤海灣盆地東營凹陷沙三段中亞 段為例[J].石油勘探與開發(fā),2023,50(4):782-794.[Wu Qianran,Xian Benzhong,Gao Xianzhi, etal.Diversity of depositional architecture and sandbodydistribution of sublacustrine fans during forced regression: A case study of Paleogene middle Sha 3 member in Dongying Sag,Bohai Bay Basin,East China[J].Petroleum Exploration and Development,2023,50(4):782-794.]
[32]Ilstad T,Elverhoi A,Issler D,etal.Subaqueous debris flow behaviour and its dependence on the sand/clay ratio:A laboratory study using particle tracking[J].Marine Geology, 20o4,213(1/2/ 3/4): 415-438.
[33]Plenderleith GE,Dodd TJH,McCarthyDJ.The effectof breached relay ramp structures on deep-lacustrine sedimentary systems[J].Basin Research,2022,34(3):1191-1219.
[34]葛智淵,許鴻翔.濁流對(duì)復(fù)雜構(gòu)造地貌的水動(dòng)力和沉積響應(yīng) [J].古地理學(xué)報(bào),2023,25(5):1090-1117.[Ge Zhiyuan,Xu Hongxiang.Hydraulic and sedimentary responses of turbidity current to structurally-controlled topography[J].Journal of Palaeogeography,2023,25(5):1090-1117.]
[35]Tian R H, Xian B Z,Wu QR,et al. Turbidite system controlled by fault interaction and linkage ona slope belt of rift Basin: Zhanhua Depression,Bohai Bay Basin,China[J].Marine and Petroleum Geology,2023,155:06377.
[36]侯云超,樊太亮,李一凡,等.鹽構(gòu)造與深水重力流的相互作 用及響應(yīng):以墨西哥灣 Sureste盆地中新統(tǒng)為例[J].沉積學(xué)報(bào), 2022,40(1):22-33.[Hou Yunchao,F(xiàn)an Tailiang,LiYifan,et al.Interactions and responses between salt structures and deep water gravity flow:A case study from the Miocene strata in the Sureste Basin, Gulf of Mexico[J].Acta Sedimentologica Sinica, 2022,40(1): 22-33.]
[37]LiuJP, XianB Z,Tan XF,et al.Depositional process and dispersal patern of a faulted margin hyperpycnal system: The Eocene Dongying Depression,Bohai Bay Basin, China[J].Marine and Petroleum Geology,2022,135:105405.
[38]Niu X B, Yang T, Cao Y C,et al. Characteristics and Formation mechanisms of gravity-flow deposits in a lacustrine Depression Basin:Examples from the Late Triassc Chang 7 oil member of the Yanchang Formation, Ordos Basin, Central China[J].Marine and Petroleum Geology,2023,148:106048.
[39]Yang T, CaoYC,Liu K Y,et al.Gravity-flow deposits caused bydifferent initiation processes in a deep-lake system[J].AAPG Bulletin,2020,104(7): 1463-1499.
[40]Wu QR, Xian B Z,Gao X Z,et al. Differences of sedimentary triggersand depositional architecture of lacustrine turbidites from normal regression to forced regression: Eocene Dongying ogy,2022,439:106222.
[41]Wang Z, Xian B Z,Liu JY,et al. Large-scale turbidite systems ofa semi-enclosed shelf sea:The Upper Miocene of eastern Yinggehai Basin, South China Sea[J]. Sedimentary Geology, 2021,425: 106006.
[42]YangT,Cao YC,Liu HN.Highstand sublacustrine fans: The role of a sudden increase in sediment supply[J].Basin Research, 2023,35(4): 1486-1508.
[43]陳亮,季漢成,張靚,等.裂陷盆地重力流沉積對(duì)基準(zhǔn)面變化 的響應(yīng):以烏里雅斯太南洼騰一下亞段為例[J].沉積學(xué)報(bào), 2016,34(3):487-496.[Chen Liang,Ji Hancheng,Zhang Liang, et al.Responses of gravity flow deposits to base-level variation in Rift Basin using acase study of Lower Tengl Formation in South Wuliyasitai Sag[J].Acta Sedimentologica Sinica,2016,34 (3): 487-496. ]
[44]王林,呂奇奇,張嚴(yán),等.鄂爾多斯盆地西南部長7油層組深水 重力流沉積巖相特征及分布模式[J].沉積學(xué)報(bào),2025,43(1): 154-168.[Wang Lin,LüQiqi, Zhang Yan,et al.Lithofacies characteristics and distribution patterns of deep water gravity flow sedimentation in the Chang 7 Oil Formation in the Southwest Ordos Basin[J].Acta Sedimentologica Sinica,2025, 43(1): 154-168.]
[45]Gilbert G K,Murphy EC. The transportation of debris by running water[M]. Washington: Department of the Interior, United States Geological Survey, 1914:1-263.
[46]Kuenen PH, Migliorini C I.Turbidity currents as a cause of graded bedding[J].The Journal of Geology,1950,58(2): 91-127.
[47]Kuenen P H. Estimated size of the Grand Banks turbidity current [J].American Journal of Science,1952,250(12): 874-884.
[48]Elison TH,Turner JS.Turbulent entrainment in stratified flows [J].Journal ofFluid Mechanics,1959,6(3): 423-448.
[49]Simons D B,Richardson E V. Forms of bed roughness in alluvial channels[J].Transactions of the American Society of Civil Engineers,1963,128(1):4-30.
[50]Middleton G V.Experiments on densityand turbidity currents: III.Deposition of sediment[J]. Canadian Journal of Earth Sciences,1967,4(3): 475-505.
[51]Chu F H,Pilkey W D,Pilkey OH. An analytical study of turbidity current steady flow[J].Marine Geology,1979,33(3/4): 205-220.
[52]SouthardJB,Mackintosh ME.Experimental test of autosuspension[J].Earth Surface Processes and Landforms,1981,6(2): 103-111.
[53]Parker G,F(xiàn)ukushima Y,Pantin HM.Self-accelerating turbidity currents[J]. Journal ofFluid Mechanics,1986,171: 145-181.
[54]Postma G,Nemec W,Kleinspehn KL.Large floating clasts in turbidites: A mechanism for their emplacement[J]. Sedimentary Geology,1988,58(1): 47-61.
[55」Kneller B,Edwards D,McCatrey W, et al. Oblique retlection of turbidity currents[J]. Geology,1991,19(3): 250-252.
[56]Dade W B,Huppert H E.A box model for non-entraining, suspension-driven gravity surges on horizontal surfaces[J]. Sedimentology, 1995,42(3): 453-470.
[57]Mohrig D,Elis C,Parker G,et al.Hydroplaning of subaqueous debris flows[J]. GSA Bulletin,1998,110(3): 387-394.
[58]Marr JG,Harff PA, Shanmugam G,et al. Experiments on subaqueous sandy gravity flows:The role of clay and water content in flow dynamics and depositional structures[J].GSA Bulletin, 2001,113(11): 1377-1386.
[59]劉忠保,龔文平,王新海,等.洪水型濁流砂體形成及分布的 沉積模擬實(shí)驗(yàn)[J].石油與天然氣地質(zhì),2008,29(1):26-30,37. [Liu Zhongbao,Gong Wenping,Wang Xinhai, et al.Sedimentation simulation tests on Formation and distribution of flood turbiditysandbodies[J].Oil amp; GasGeology,2008,29(1):26- 30,37.]
[60]鄢繼華,陳世悅,姜在興.三角洲前緣濁積體成因及分布規(guī)律 研究[J].石油實(shí)驗(yàn)地質(zhì),2008,30(1):16-19,25.[Yan Jihua, Chen Shiyue,Jiang Zaixing. Genesis and distribution regularity of the turbidite bodies inthe delta front[J].PetroleumGeology amp; Experiment,2008,30(1): 16-19,25.]
[61]Lamb MP,McElroyB,KoprivaB,et al.Linking river-flood dynamics to hyperpycnal-plume deposits: Experiments,theory,and geological implications[J]. Geological Society of America Bulletin,2010,122(9/10): 1389-1400.
[62]Cantero MI, Cantelli A,Pirmez C,et al.Emplacement of massive turbidites linked to extinction of turbulence in turbidity currents[J]. Nature Geoscience,2015,5(1):42-45.
[63]CartignyMJB,Ventra D,Postma G,et al. Morphodynamics and sedimentary structures of bedforms under supercritical-flow conditions:New insights from flume experiments[J]. Sedimentology,2014, 61(3): 712-748.
[64]de Leeuw J,Eggenhuisen JT,CartignyMJB.Morphodynamics ofsubmarine channel inceptionrevealed by new experimental approach[J]. Nature Communications,2016,7: 10886.
[65]Ge Z Y,Nemec W, Gawthorpe R L,et al. Response of unconfined turbiditycurrenttonormal-fault topography[J].Sedimentology,2017, 64(4): 932-959.
[66]Pohl F, Eggenhuisen JT,Tilston M, et al. New flow relaxation mechanism explains scour fields at the end of submarine channels[J]. Nature Communications,2019,10(1): 4425.
[67]Miramontes E,Eggenhuisen JT,Jacinto R S,et al.Channelleveeevolution in combined contour current-turbidity current flows from flume-tank experiments[J]. Geology,2020,48(4): 353-357.
[68]Salinas JS,Balachandar S, Shringarpure M,et al. Anatomy of subcritical submarine flows with a lutocline and an intermediate destruction layer[J]. Nature Communications,2021,12(1): 1649.
[69]Wahab A,Hoyal D C, Shringarpure M, et al.A dimensionless framework for predicting submarine fanmorphology[J].Nature Communications,2022,13(1):7563.
[70]夏長淮.沉積模擬技術(shù)在油氣田勘探開發(fā)中的應(yīng)用:以東濮 凹陷白廟氣田為例[D].廣州:中國科學(xué)院廣州地球化學(xué)研究 所,2003:15-22.[Xia Changhuai. Application of sedimentation simulation techniquesin oil and gas field exploration:A case study about Baimiao gas field in Dongpu Depression[D].Guangzhou: Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,2003:15-22.]
[71]Kane IA,McCaffrey W D,PeakallJ. Controls on sinuosity evolutionwithin submarine channels[J].Geology,20o8,36(4): 287-290.
[72]Straub KM,Mohrig D,McelroyB,et al. Interactions between turbidity currentsand topography in aggrading sinuous submarine channels:Alaboratory study[J].GSABulletin,2008,20(3- 4):368-385.
[73]RowlandJC,Hilley GE,F(xiàn)ildani A.ATest of Initiation of Submarine Leveed Channels by Deposition Alone[J]. Jourmal of Sedimentary Research,2010,80(8):710-727.
[74]Cartigny MJB,Eggenhuisen JT,Hansen EW M,et al. Concentration-dependent flow stratification in experimental high-density turbidity currents and their relevance to turbidite facies models[J]. Journal of Sedimentary Research,2013,83 (11):4840.
[75]Eggenhuisen JT,McCaffrey WD.The vertical turbulence structure of experimental turbidity currents encountering basal obstructions: Implications for vertical suspended sediment distribution in non-equilibrium currents[J]. Sedimentology,2012,59 (3): 1101-1120.
[76]Baas JH,Van Kesteren W,Postma G.Deposits of depletive high-density turbidity currents:A flume analogue of bed geometry,structure and texture[J]. Sedimentology,20o4,51(5):1053- 1088.
[77]XU JP. Normalized velocity profiles of field-measured turbidity currents[J]. Geology,2010,38(6):563-566.
[78]Kneller B,Buckee C. The structure and fluid mechanics of turbidity currents: Areview of some recent studies and their geological implications[J]. Sedimentology,20o0,47(Suppl.1): 62-94.
[79]Kostic S,Parker G,MarrJG.Role of turbidity currents in setting the foreset slopeof clinoforms prograding into standing fresh water[J].Journal of Sedimentary Research,20o2,72(3): 353-362.
[80]PohlF,EggenhuisenJT,Cartigny MJB,et al. The influence of aslope break on turbidite deposits: An experimental investigation[J].Marine Geology,2020,424: 106160.
[81]Wilkin J, Cuthbertson A,Dawson S,et al. The response of igh density turbidity currents and their deposits to an abrupt channel terminationata slope break:Implications forchannel-lobe transition zones[J]. Sedimentology,2023,70(4): 1164-1194.
[82」Sequeiros O E. Estimating turbidity current conditions from channel morphology:A Froude number approach[J]. Journal of Geophysical Research: Oceans,2012,117(C4):C04003.
[83]Sequeiros OE,CantelliA,ViparelliE,etal.Modeling turbidity currents with nonuniform sediment and reverse buoyancy[J]. Water Resources Research,2009,45(6): W06408.
[84]Schieber J, Southard J, Thaisen K.Accretion of mudstone beds from migrating floccule ripples[J].Science,2007,318(5857): 1760-1763.
[85]Elerian M, van Rhee C,Helmons R.Experimental and numerical modelling of deep-sea-mining-generated turbidity currents [J].Minerals,2022,12(5): 558.
[86]Nomura S,De Cesare G,F(xiàn)uruichi M,et al.Quasi-stationary flowstructure in turbidity currents[J].International Journal of Sediment Research,2020,35(6): 659-665.
[87]Ono K,Naruse H, Yao QF, et al. Multiple scours and upward finingcaused by hydraulic jumps: Implications for the recognition ofcyclic steps in the deepwater stratigraphic record[J].Journal of SedimentaryResearch,2023,93(4):243-255.
[88]de Vet MGW,F(xiàn)ernandez R,Baas JH, et al. Streamwise turbulence modulation in non-uniform open-channel clay suspension flows[J].Journal of Geophysical Research:Earth Surface,2023, 128(8): e2022JF006781.
[89]Parker G,Garcia M,F(xiàn)ukushima Y,etal.Experiments on turbidity currents over an erodible bed[J]. Journal of Hydraulic Research,1987,25(1):123-147.
[90]Garcia M,Parker G.Experiments on hydraulic jumps in turbidity currents near a canyon-fan transition[J].Science,1989,245 (4916): 393-396.
[91]Garcia M, Parker G. Experiments on the entrainment of sediment into suspension by a dense bottom current[J]. Journal of Geophysical Research: Oceans,1993,98(C3): 4793-4807.
[92]Canteli A,Johnson S,White JDL,et al.Sediment sorting in thedepositsof turbiditycurrentscreated byexperimental modeling of explosive subaqueous eruptions[J]. The Journal of Geology,2008,116(1): 76-93.
[93]張春生,劉忠保,施冬,等.涌流型濁流形成及發(fā)展的實(shí)驗(yàn)?zāi)?擬[J].沉積學(xué)報(bào),2002,20(1):25-29.[Zhang Chunsheng,Liu Zhongbao, Shi Dong,et al. The simulation experiment of surgetype turbidity current formation and development[J]. Acta Sedimentologica Sinica,2002,20(1): 25-29.]
[94]劉忠保,龔文平,張春生,等.沉積物重力流砂體形成及分布 的沉積模擬試驗(yàn)研究[J].石油天然氣學(xué)報(bào)(江漢石油學(xué)院學(xué) 報(bào)),2006,38(3):20-22.[Liu Zhongbao,Gong Wenping, Zhang Chunsheng, et al. Experimental study on sedimentary modeling on the formation and distribution of gravity flow sandbody[J]. Journal of Oil and Gas Technology (Journal of Jianghan Petroleum Institute),2006,38(3): 20-22.]
[95]鄢繼華,陳世悅,姜在興,等.?dāng)嘞莺枵饾岱e巖成因模擬實(shí) 驗(yàn)[J].古地理學(xué)報(bào),2007,9(3):277-282.[Yan Jihua,Chen Shiyu,Jiang Zaiaug,t ai. Suiaung vApvicn Un gncsis UI seismo-turbidites in rift lacustrine Basin[J].Journal of Palaeogeography,2007,9(3): 277-282.]
[96]Baas JH,Best JL,Peakall J,et al. Aphase diagram for turbulent,transitional,and laminar claysuspension flows[J].Journal of Sedimentary Research,2009,79(4): 162-183.
[97]Baas JH, Best JL,Peakall J.Depositional processes,bedform development and hybrid bed formation in rapidly decelerated cohesive (mud-sand) sediment flows[J]. Sedimentology,2011,58 (7): 1953-1987.
[98]Baker ML,Baas JH. Mixed sand-mud bedforms produced by transient turbulent flows in the fringe of submarine fans: Indicators of flow transformation[J]. Sedimentology,2020,67(5): 2645-2671.
[99]袁琳.蒙脫石的脹縮機(jī)理及改性技術(shù)研究[D].長沙:長沙理 工大學(xué),2007:5-7.[Yuan Lin.The sweling and shrinking mechanism and modification of montmorillonite[D]. Changsha: Changsha University of Science amp; Technology,20o7: 5-7.]
[100]Normark WR.Fan valleys,channels,and depositional lobes on modern submarine fans: Characters for recognition of sandy turbiditeenvironments[J].AAPGBulletin,1978,62(6): 912-931.
[101]Hubbard SM,CovaultJA,F(xiàn)ildani A,etal. Sediment transfer and deposition in slope channels: Deciphering the record of enigmatic deep-sea processes from outcrop[J]. GSA Bulletin, 2014,126(5/6): 857-871.
[102]Gong CL,Steel RJ,QiK,etal.Deep-waterchannel morphologies,architectures,and population densities in relation to stacking trajectories and climate states[J]. GSA Bulletin,2021, 133(1/2): 287-306.
[103]Mayall M,Jones E,Casey M.Turbidite channel reservoirs: Keyelements in facies prediction and effective development [J].Marine and Petroleum Geology,2006,23(8): 821-841.
[104]Keevil GM,PeakallJ,Best JL,et al. Flow structure in sinuous submarine channels: Velocity and turbulence structure of an experimental submarine channel[J]. Marine Geology,2006,229 (3/4): 241-257.
[105]Wynn R B,Kenyon NH,Masson D G,et al.Characterization and recognition of deep-water channel-lobe transition zones[J]. AAPG Bulletin,2002, 86(8): 1441-1462.
[106]Macdonald HA,Wynn R B,Huvenne VAI,et al. New insights into the morphology,fill,and remarkable longevity (gt;0 : 2 m.y.)of modern deep-water erosional scours along the northeast Atlantic margin[J]. Geosphere,2011,7(4): 845-867.
[107]Dorrell RM,PeakallJ,Sumner E J,et al.Flow dynamics and mixing processes in hydraulic jump arrays:Implications for channel-lobe transition zones[J]. Marine Geology,2016,381: 181-193.
[108]Carvajal C,PaullCK,Caress DW,etal. Unraveling the channellobetransition zone with high-resolution AUV bathymetry: Navy Fan,offshore Baja California,Mexico[J].Journal of Sedimentary Research,2017,87(10): 1049-1059.
[109]Komar P D.Hydraulic jumps in turbidity currents[J].GSA Bulletin,1971,82(6):1477-1488.
[110]Lu Y T,Luan X W, Shi B Q,et al. Migrated hybrid turbiditecontourite channel-lobe complex of the Late Eocene Rovuma Basin,East Africa[J].Acta Oceanologica Sinica,2021,40(2): 81-94.
[111]ChenYH, Yao G S,Wang XF,et al.Flow processs of the interaction between turbidity flows and bottom currents in sinuousunidirectionally migrating channels:An example from the Oligocene channels in the Rovuma Basin,offshore Mozambique [J].Sedimentary Geology,2020,404: 105680.
[112]李華,何明薇,邱春光,等.深水等深流與重力流交互作用沉 積(2000—2022年)研究進(jìn)展[J].沉積學(xué)報(bào),2023,41(1):18- 36.[Li Hua,He Mingwei,Qiu Chunguang,et al. Research processes on deep-water interaction between contour current and gravity flow deposits,2000 to 2022[J].Acta Sedimentologica Sinica,2023,41(1): 18-36.]
[113]Fedele JJ, Bayliss N. Hydraulic controls on turbidity channel and slope gullies lateral migration induced by contour currents [M]//AbubakarA,Hakami A.Second international meeting for applied geoscience amp; energy.Houston: Society of Exploration Geophysicists,2022: 2460-2463.
[114]Hage S,Cartigny MJB,Clare MA,et al. How to recognize crescentic bedforms formed by supercritical turbidity curents in the geologic record: Insights from active submarine channels [J].Geology,2018,46(6): 563-566.
[115]Postma G,Cartigny MJB. Supercritical and subcritical turbidity currents and their deposits: A synthesis[J]. Geology,2014,42 (11): 987-990.
[116]Smith DP,Kvitek R, Iampietro PJ, et al.Twenty-nine months of geomorphic change in Upper Monterey Canyon (2o02-2005) [J].Marine Geology,2007,236(1/2):79-94.
[117]Fildani A,Normark W R, Kostic S,et al. Channel Formation by flow stripping:Large-scale scour features along the Monterey East Channel and their relation to sediment waves[J]. Sedimentology,2006,53(6):1265-1287.
[118]Covault JA,Kostic S,PaullC K,et al. Submarine channel initiation,filing and maintenance from sea-floor geomorphology and morphodynamic modelling of cyclic steps[J]. Sedimentology,2014,61(4): 1031-1054.
[119]Zhong G F, Cartigny MJB, Kuang Z G,et al. Cyclic steps along the South Taiwan Shoal and West Penghu submarine canyons on the northeastern continental slope of the South China Sea[J]. GSA Bulletin,2015,127(5/6): 804-824.
[120]Symons WO,SumnerEJ, Talling PJ, et al.Large-scale sediment waves and scours on the modern seafloor and their implications for the prevalence of supercritical flows[J]. Marine Genlnov 2016 371:130-148
[121」林承焰,陳柄屹,任麗華,等.沉積數(shù)值模擬研究現(xiàn)狀及實(shí)例 [J].地質(zhì)學(xué)報(bào),2023,97(8):2756-2773.[Lin Chengyan,Chen Bingyi,Ren Lihua,etal.A review of depositional numerical simulation and a case study[J].Acta GeologicaSinica,2023,97 (8): 2756-2773. ]
[122]Gladstone C,Woods A W. On the application of box models to particle-driven gravity currents[J].Journal ofFluid Mechanics, 2000,416:187-195.
[123]Launder BE. Turbulence modeling for CFD.By D.C.WILCOX.DCW Industries Inc.,1993.460pp.\$75.[J]. Journal ofFluid Mechanics,1995,289:406-407
[124]Meiburg E,Radhakrishnan S,Nasr-Azadani M. Modeling gravityand turbidity currents:Computational approaches and challenges[J].Applied MechanicsReviews,2015,67(4):040802.
[125]Yeh TH, Cantero M, Canteli A,et al. Turbidity current with a roof: Success and failure of RANS modeling for turbidity currentsunder strongly stratified conditions[J].Journal of Geophysical Research: Earth Surface,2013,118(3):1975-1998.
[126]Stevens RJAM,Wilczek M,Meneveau C. Large-eddy simulationstudy of thelogarithmic law for second-and higher-order moments in turbulent wall-bounded flow[J].Journal of Fluid Mechanics,2014,757: 888-907.
[127]王星星,王英民,高勝美,等.深水重力流模擬研究進(jìn)展及對(duì) 海洋油氣開發(fā)的啟示[J].中國礦業(yè)大學(xué)學(xué)報(bào),2018,47(3): 588-602.[Wang Xingxing, Wang Yingmin, Gao Shengmei, et al.Advancements of the deep-water gravity flow simulations and their implications for exploitation of marine petroleum[J]. Journal of China University of Miningamp; Technology,2018,47 (3): 588-602.]
[128]Goodarzi D,Sookhak Lari K,Khavasi E,et al. Large eddy simulation of turbidity currents in a narrow channel with different obstacle configurations[J].Scientific Reports,2020,10(1): 12814.
[129]DaiA,Wu C S. High-resolution simulations of cylindrical gravity currents in a rotating system[J].Journal of Fluid Mechanics,2016,806: 71-101.
[130]Howlett D M, Ge Z Y,Nemec W,et al.Response of unconfined turbiditycurrent to deep-water foldand thrust belt topography:Orthogonal incidence on solitary and segmented folds [J].Sedimentology, 2019, 66(6): 2425-2454.
[131]Abd El-Gawad S,Cantelli A,Pirmez C,etal. Three-dimensional numerical simulation of turbidity currents ina submarine channel on the seafloor of the Niger Delta slope[J].Journal of Geophysical Research: Oceans,2012,117(C5): C05026.
[132]Cai ZR, Naruse H. Inverse analysis of experimental scale turbiditycurrents using deep learning neural networks[J]. Journal ofGeophysical Research:Earth Surface,2021,126(8): e2021JF006276.
[133]Naruse H, Nakao K. Inverse modeling of turbidity currents using anartificial neural network approach: Verification for field appIcauon[JJ. Eartn Suriace DynaImics,ZUz1,y(?):1091- 1109.
[134]Baghalian S,Ghodsian M. Experimental analysis and prediction of velocity profiles of turbidity current ina channel with abrupt slope using artificial neural network[J].Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2017,39(11): 4503-4517.
[135]Guo X S,Luo QY, Stoesser T,etal.Evolution of high-density submarine turbiditycurrent and itsinteractionwith apair of parallel suspended pipes[J].Physics of Fluids,2023,35(8): 086608.
[136]Tang XQ,Koh CG,Luo M.Numerical simulation of turbidity currents using consistent particle method[J].Advances in Water Resources,2023,180:104536.
[137]StraussM, Glinsky M E. Turbidity current flow over an erodible obstacle and phases of sediment wave generation[J]. Journal of Geophysical Research: Oceans,2012,117(C6): C06007.
[138]Teles V,Chauveau B,Joseph P,et al.CATS: A process-based model for turbulent turbidite systems at the reservoir scale[J]. Comptes Rendus Geoscience,2016,348(7): 489-498.
[139] Tian D M,Jiang T,Wang H,et al.Flow dynamics and sedimentation at a turbidity channel confluencein the Yinggehai Basin, northwestern South China sea[J]. Geoenergy Science and Engineering,2023,227:211927.
[140]Basani R, Janocko M,Cartigny MJB,et al. Mass FLOW(204號(hào) 3DTM as a simulation tool for turbidity currents: Some preliminaryresults[M]//MartiniusAW,RavnasR,Howell JA, etal. From depositional systems to sedimentary successions on the Norwegian continental margin. Chichester:International Association of Sedimentologists,2014: 587-608.
[141]Boysan F,WeberR,SwithenbankJ,etal.Modeling coal-fired cyclone combustors[J]. Combustion and Flame,1986,63(1-2): 73-86.
[142]Georgoulas A N,Angelidis PB,Panagiotidis TG, et al. 3D numerical modelling of turbidity currents[J].Environmental Fluid Mechanics,2010,10(6): 603-635.
[143]Porcile G,Enrile F,Besio G,et al. Hydrostatic vs. non-hydrostatic modelling of density currents developing two dimensionallyon steep andmild slopes[J].Applied Ocean Research, 2022,121: 103085.
[144]Porcile G,Bolla Pitaluga M,F(xiàn)rascati A,et al.Modelling the air-sea-land interactions responsible for the direct trigger of turbidity currents by tropical cyclones[J]. Applied Ocean Research,2023,137:103602.
[145]Griffiths CM,Dyt C,Paraschivoiu E,etal. Sedsim in hydrocarbonexploration[M]//Merriam DF,DavisJC.Geologic modeling and simulation:Sedimentary systems.New York: Springer,2001: 71-97.
[146]Huang H,Imran J,Pirmez C,etal.The critical densimetric Froude number of subaqueous gravity currents can be nonunity or non-existent[J]. Journal of Sedimentary Research, 2009,79(7): 479-485.
[147]ZhaoL,Ouillon R,Vowinckel B,et al.Transitionofahyperpycnal flow into a saline turbidity current due to differential diffusivities[J]. Geophysical Research Letters,2018,45(21):11875- 11884.
[148]Picot M,Droz L,Marsset T, et al. Controls on turbidite sedimentation: Insights from a quantitative approach of submarine channel and lobe architecture (Late Quaternary Congo Fan)[J]. Marine and Petroleum Geology,2016,72:423-446.
[149]Sweet ML,Gaillot G T, Jouet G, et al. Sediment routing from shelf to Basin floor in the Quaternary Golo System of eastern Corsica,F(xiàn)rance,western Mediterranean Sea[J].GSA Bulletin, 2020,132(5/6):1217-1234.
[150]年廷凱,沈月強(qiáng),鄭德鳳,等.海底滑坡鏈?zhǔn)綖?zāi)害研究進(jìn)展 [J].工程地質(zhì)學(xué)報(bào),2021,29(6):1657-1675.[Nian Tingkai, Shen Yueqiang,Zheng Defeng,et al. Research advances on the chain disasters of submarine landslides[J]. Journal of Engineering Geol0gy,2021,29(6):1657-1675.]
[151]Dott R H. Dynamics of subaqueous gravity depositional processes[J]. AAPG Bulletin,1963,47(1): 104-128 DottR H. Dynamics of subaqueous gravity depositional processes[J]. AAPG Bulletin,1963,47(1):104-128.
Abstract:[Significance]Deep-water gravityflowdepositsare,in efect,records of extreme climatic events and tectonic activities (e.g.paleoseismic events).Accumulations of these sediments significantly affct thenumber and extent of worldwide reserves ofoiland gasresources.The event-driven nature of the deep-water gravity flow process,together with the unique nature of each deposition site,presents a significant challenge to direct observation in the field.At present,simulationof thedynamicsanddistributionpatterns ofdeep-water gravityflowdeposits is the primary approach.[Progress] This study reviews the advances in both physicaland numerical simulation of the processes and paternsof deep-water gravityflow deposits.Itbegins with asummaryof the principles and progress inmonitoring technology and laboratoryconstruction of physical simulation models,then examines the factors influencing such experiments:material composition and content,flow stateand energy diferences in the dynamics of the fluid flow. Analysis of the formation,transportation and depositional processesof deep-water gravity flow provides insights nto the complex dynamics involved,in terms both of its behavior aloneand when influenced byexternal factors (e.g., contour currnts).The studyalso reviews advances in the simulation of sedimentaryprocesses influenced bythe structureof the fluid,taking account of hydrodynamic parameters and complex topography.Numerical simulation is also crucial tounderstandingdeep-water gravityflow.This study providesacomprehensive review ofthe historicaldevelopment of numerical simulation techniques and presently available numerical simulation platforms.[Conclusions and Prospects]The limitedabilityof physical models to simulatethe intricate dynamicsand complex interactions between sediment particles and fluidflow in deep-water gravity flowdepositsare further discussed.The spatiotemporal scaleofalaboratorysetting hinders theabilitytoreproduce thebehaviorof deep-water gravityflowthat exists inrealworld conditions,and it isunlikelythat hydrodynamic parameters(variation in water velocity,sedimentconcentration etc.)are accurately predicted byphysical models.Numerical simulation ofers a promising alternative for studying deep-water gravityflowdeposits dueto the mathematicalabilitytowork atascaleconsistent with real-worldconditions.However,although computational fluid dynamics simulations provide valuable information about various depositional mechanisms that occur in deep-water environments,they have limited accuracy when applied to certain phenomena.In particular,the accurate capture of the behaviorof high particle concentrations in turbidity currnts and predictionof the amount of erosion theycause remain significant challenges due to the uncertainties assciated with factorssuch as grain size distribution and bedcomposition.Interdisciplinary colaboration is crucial in confronting these challenges and advancing the understanding of deep-water gravity flow sedimentation.Deper insights into the underlying mechanismsat playduring these processes willbest beobtainedifkey results from physical model simulationare integrated with outcomes from numerical simulation.This approach presents novel guidance for exploring oil and gas reserves in deep-water environments and preventing geological disasters.
Key words:deep-water gravityflow;turbidity current;physical simulation;numerical simulation;research progress