High‐resolution sequence stratigraphy of a complex, incised valley succession, Cobequid Bay — Salmon River estuary, Bay of Fundy, Canada

Sedimentology - Tập 41 Số 6 - Trang 1069-1091 - 1994
Robert W. Dalrymple1, Brian A. Zaitlin2
1Department of Geological Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada
2PanCanadian Petroleum Ltd, PO Box 2850, Calgary, Alberta T2P 2S5 Canada

Tóm tắt

ABSTRACTThe post‐glacial succession in the Cobequid Bay — Salmon River incised valley contains two sequences, the upper one incomplete. The lower sequence contains only highstand system tracts (HST) deposits which accumulated under microtidal, glacio‐marine deltaic conditions. The upper sequence contains two, retrogradationally stacked parasequences. The lower one accumulated in a wave‐dominated estuarine environment under micro‐mesotidal conditions. It belongs to the lowstand system tract (LST) or early transgressive system tract (TST) depending on the timing and location of the lowstand shoreline, and contains a gravel barrier that has been overstepped and preserved with little modification. The upper parasequence accumulated in the modern, macrotidal estuary, and is assignable to the late TST. Recent, net progradation of the fringing marshes indicates that a new HST has begun.The sequence boundary separating the two sequences was formed by fluvial incision, and perhaps also by subtidal erosion during the relative sea level fall. Additional local erosion by waves and tidal currents occurred during the transgression. The base of the macrotidal sands is a prominent tidal ravinement surface which forms the flooding surface between the backstepping estuarine parasequences. Because fluvial deposition continued throughout the transgression, the fluvial‐estuarine contact is diachronous and cannot be used as the transgressive surface. The maximum flooding surface will be difficult to locate in the macrotidal sands, but is more easily identified in the fringing muddy sediments.These observations indicate that: (1) large incised valleys may contain a compound fill that consists of more than one sequence; (2) relative sea level changes determine the stratal stacking patterns, but local environmental factors control the nature of the facies and surfaces; (3) these surfaces may have complex origins, and commonly become amalgamated; (4) designation of the transgressive surface (and thus the LST) is particularly difficult as many of the prominent surfaces in the valley fill are diachronous facies boundaries; and (5) the transgression of complex topography may cause geologically instantaneous changes in tidal range, due to resonance under particular geographical configurations.

Từ khóa


Tài liệu tham khảo

Allen G.P., 1991, Sedimentary processes and facies in the Gironde estuary: A recent model of macrotidal estuarine systems, Mem. Can. Soc. petrol. Geol., 16, 29

Allen G.P., 1970, Contribution á l'etude des facies de comblement et interpretation paléogéographique de l'evolution des milieux sédimentaires recents et actuels de l'estuaire de la Gironde, Bull. Inst. Geol. Bassin d'Aquitaine, 8, 99

Allen G.P., 1993, Sequence stratigraphy and facies model of an incised valley fill: the Gironde Estuary, France, J. sedim. Petrol., 63, 378

Allen G.P., 1988, Stratigraphic and facies model of a transgressing estuarine valley fill in the Gironde estuary (France), Mem. Can. Soc. petrol. Geol., 15, 575

10.1016/0037-0738(90)90003-C

10.1016/0025-3227(88)90059-X

Amos C.L., 1978, The post‐glacial evolution of the Minas Basin, Nova Scotia: A sedimentological interpretation, J. sedim. Petrol., 48, 965

Amos C.L., 1980, The sedimentary character of the Minas Basin, Bay of Fundy, Paps geol. Surv. Canada, 80, 153

Amos C.L., 1991, The post‐glacial evolution of Chignecto Bay, Bay of Fundy, and its modern environments of deposition, Mem. Can, Soc. petrol. Geol., 16, 59

10.1007/BF02281699

Boyd R., 1992, Estuarine sedimentation on the Eastern Shore of Nova Scotia, J. sedim. Petrol., 62, 569

10.1130/0016-7606(1990)102<1268:ACOTSR>2.3.CO;2

Dalrymple R.W. Amos C.L.&Yeo G.(1992a)Nature and evolution of tidal sedimentation in the Minas Basin—Cobequid Bay area Bay of Fundy. Guidebk. Geol. Ass. Canada Annual Meeting Wolfville Trip A—8.

Dalrymple R.W., 1994, Incised‐Valley Systems: Origin and Sedimentary Sequences, Spec. Publ. Soc. econ. Paleont. Miner., Tulsa, 51

10.1111/j.1365-3091.1990.tb00624.x

Dalrymple R.W., 1991, Temporal and spatial patterns of rhythmite deposition on mudflats in the macrotidal Cobequid Bay — Salmon River estuary, Bay of Fundy, Canada, Mem. Can. Soc. petrol Geol., 16, 137

Dalrymple R.W.&Zaitlin B.A.(1989)Tidal sedimentation in the macrotidal Cobequid Bay — Salmon River Estuary Bay of Fundy. Field Guide Can. Soc. petrol. Geol. 2nd. Int. Symp. Clastic Tidal Deposits Calgary.

10.1306/D4267A69-2B26-11D7-8648000102C1865D

10.1016/0025-3227(84)90155-5

Demarest J.M., 1987, Stratigraphic record of Quaternary sea levels: Implications for more ancient strata, Spec. Publ. Soc. econ. Paleont. Miner., Tulsa, 41, 223

Hennigar T.W.(1972)Hydrogeology of the Truro Area Nova Scotia. Repts N.S. Dept. Mines Groundwater Sect. 72– 1.

10.1016/0025-3227(88)90055-2

Knight R.J.(1977)Sediments Bedforms and Hydraulics in a Macrotidal Environment Cobequid Bay (Bay of Fundy).PhD thesis McMaster University Hamilton .

Knight R.J., 1980, Linear sand bar development and tidal current flow in Cobequid Bay, Bay of Fundy, Nova Scotia, Pap. geol. Surv. Canada, 80, 123

Plint A.G., 1988, Sharp‐based shoreface sequences and ‘offshore bars’ in the Cardium Formation of Alberta; their relationship to relative changes in sea level, Spec. Publ Soc. econ. Paleont. Miner., Tulsa, 42, 357

Posamentier H.W., 1992, High resolution sequence stratigraphy — the East Coulee delta, Alberta, J. sedim. Petrol., 62, 310

Posamentier H.W., 1992, Forced regressions in a sequence stratigraphic framework: concepts, examples, and exploration significance, Bull. Am. Ass. petrol. Geol., 76, 1687

Posamentier H.W., 1988, Eustatic controls on clastic deposition I — a conceptual framework, Spec. Publ. Soc. econ. Paleont. Miner., Tulsa, 42, 109

Posamentier H.W., 1988, Eustatic controls on clastic sedimentation II — Sequence and systems tract models, Spec. Publ. Soc. econ. Paleont. Miner., Tulsa, 42, 125

Reinson G.E., 1988, Reservoir geology of Crystal Viking field, Lower Cretaceous estuarine tidal channel — bay complex, south‐central Alberta, Bull. Am. Ass. petrol. Geol., 72, 1270

Ricketts B.D., 1991, Lower Paleocene drowned valley and barred estuaries, Canadian Arctic Islands: aspects of their geomorphological and sedimentological evolution, Mem. Can. Soc. petrol. Geol., 16, 91

10.1139/e83-145

Stea R.R., 1984, Correlation of Quaternary Chronologies, 279

10.1016/0033-5894(87)90078-0

Vail P.R., 1977, Seismic stratigraphy and global changes in sea level, parts 1– 11, Mem. Ass. petrol. Geol., Tulsa, 26, 49

VanWagoner J.C. Mitchum R.M. Campion K.M.&Rahmanian V.D.(1990)Siliciclastic Sequence Stratigraphy in Well Logs Cores and Outcrops: Concepts of High‐resolution Correlation of Time and Facies.Methods in Exploration Ser. Am. Ass. petrol. Geol. 7.

Wagoner J.C., 1988, An overview of the fundamentals of sequence stratigraphy and key definitions, Spec. Publ. Soc. econ. Paleont. Miner., Tulsa, 42, 39

Wightman D.M.(1980)Late Pleistocene glacio‐fluvial and glacio‐marine sediments on the north side of Minas Basin Nova Scotia.PhD thesis Dalhousie University Halifax .

Wightman D.M., 1978, Postglacial emergence in Atlantic Canada, Geosci. Canada, 5, 61

10.1111/j.1365-3091.1989.tb01743.x

10.1016/0037-0738(93)90016-X

10.1016/0037-0738(93)90022-W

Zaitlin B.A.(1987)Sedimentology of the Cobequid Bay—Salmon River estuary Bay of Fundy Canada.PhD thesis Queen's University Kingston .

Zaitlin B.A., 1994, The stratigraphic organization of incised‐valley systems associated with relative sea‐level changes, Spec. Publ. Soc. econ. Paleont. Miner., Tulsa, 51

10.1007/978-1-4613-8988-0_16

Thông tin
Thông tin xuất bản

Sedimentology

Tập 41 Số 6

1069-1091

Thông tin tác giả