Phytocenoses of the Ob Estuary and Kara Sea Shelf in the Late Spring Season     

Sukhanova  I. N.  Flint  M. V.  Sakharova  E. G.  Fedorov  A. V.  Makkaveev  P. N.  Nedospasov  A. A. 《Oceanology》2018,58(6):802-816

Oceanology - Based on the material obtained in the spring–summer season of 2016, the composition and quantitative distribution of phytoplankton in the Ob estuary and over the Kara Sea shelf...  相似文献   

Radiation-Geochemical Stability of Bottom Sediments in the Ob and Yenisei Estuaries and Adjacent Shoal Area of the Kara Sea     

Miroshnikov  A. Yu.  Flint  M. V.  Asadulin  En. E.  Komarov  Vl. B. 《Oceanology》2020,60(6):817-830

Oceanology - This paper reports the results of investigations on the radioecological state of bottom sediments of the Ob–Yenisei shoal area and Ob and Yenisei estuaries. Materials were...  相似文献   

Depositional architecture and sequence stratigraphy of the Karoo basin floor to shelf edge succession, Laingsburg depocentre, South Africa     

S.S. Flint  D.M. HodgsonA.R. Sprague  R.L. BruntW.C. Van der Merwe  J. FigueiredoA. Prélat  D. BoxC. Di Celma  J.P. Kavanagh 《Marine and Petroleum Geology》2011,28(3):658-674

The Laingsburg depocentre of the SW Karoo Basin, South Africa preserves a well-exposed 1200 m thick succession of upper Permian strata that record the early filling of a basin during an icehouse climate. Uniformly fine-grained sandstones were derived from far-field granitic sources, possibly in Patagonia, although the coeval staging and delivery systems are not preserved. Early condensed shallow marine deposits are overlain by distal basin plain siltstone-prone turbidites and volcanic ashes. An order of magnitude increase in siliciclastic input to the basin plain is represented by up to 270 m of siltstone with thin sandstone turbidites (Vischkuil Formation). The upper Vischkuil Formation comprises three depositional sequences, each bounded by a regionally developed zone of soft sediment deformation and associated 20-45 m thick debrite that represent the initiation of a major sand delivery system. The overlying 300 m thick sandy basin-floor fan system (Unit A) is divisible into three composite sequences arranged in a progradational-aggradational-retrogradational stacking pattern, followed by up to 40 m of basin-wide hemipelagic claystone. This claystone contains Interfan A/B, a distributive lobe system that lies 10 m beneath Unit B, a sandstone-dominated succession that averages 150 m thickness and is interpreted to represent a toe of slope channelized lobe system. Unit B and the A/B interfan together comprise 4 depositional sequences in a composite sequence with an overall basinward-stepping stacking pattern, overlain by 30 m of hemipelagic claystone. The overlying 400 m thick submarine slope succession (Fort Brown Formation) is characterized by 10-120 m thick sand-prone to heterolithic packages separated by 30-70 m thick claystone units. On the largest scale the slope stratigraphy is defined by two major cycles interpreted as composite sequence sets. The lower cycle comprises lithostratigraphic Units B/C, C and D while the upper cycle includes lithostratigraphic Units D/E, E and F. In each case a sandy basal composite sequence is represented by an intraslope lobe (Units B/C and D/E respectively). The second composite sequence in each cycle (Units C and E respectively) is characterized by slope channel-levee systems with distributive lobes 20-30 km down dip. The uppermost composite sequence in each cycle (Units D and F respectively) are characterised by deeply entrenched slope valley systems. Most composite sequences comprise three sequences separated by thin (<5 m thick) claystones. Architectural style is similar at individual sequence scale for comparable positions within each composite sequence set and each composite sequence. The main control on stratigraphic development is interpreted as late icehouse glacio-eustasy but along-strike changes associated with changing shelf edge delivery systems and variable bathymetry due to differential substrate compaction complicate the resultant stratigraphy.  相似文献   

Feeding and distribution of zooplankton in the desalinated “lens” in the Kara Sea: Impact of the vertical salinity gradient     

A. F. Pasternak  A. V. Drits  G. A. Abyzova  T. N. Semenova  V. M. Sergeeva  M. V. Flint 《Oceanology》2015,55(6):863-870

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Clinoform architecture and along‐strike facies variability through an exhumed erosional to accretionary basin margin transition     

Miquel Poyatos‐Mor  George D. Jones  Rufus L. Brunt  Daniel E. Tek  David M. Hodgson  Stephen S. Flint 《Basin Research》2019,31(5):920-947

Exhumed basin margin‐scale clinothems provide important archives for understanding process interactions and reconstructing the physiography of sedimentary basins. However, studies of coeval shelf through slope to basin‐floor deposits are rarely documented, mainly due to outcrop or subsurface dataset limitations. Unit G from the Laingsburg depocentre (Karoo Basin, South Africa) is a rare example of a complete basin margin scale clinothem (>60 km long, 200 m‐high), with >10 km of depositional strike control, which allows a quasi‐3D study of a preserved shelf‐slope‐basin floor transition over a ca. 1,200 km² area. Sand‐prone, wave‐influenced topset deposits close to the shelf‐edge rollover zone can be physically mapped down dip for ca. 10 km as they thicken and transition into heterolithic foreset/slope deposits. These deposits progressively fine and thin over tens of km farther down dip into sand‐starved bottomset/basin‐floor deposits. Only a few km along strike, the coeval foreset/slope deposits are bypass‐dominated with incisional features interpreted as minor slope conduits/gullies. The margin here is steeper, more channelized and records a stepped profile with evidence of sand‐filled intraslope topography, a preserved base‐of‐slope transition zone and sand‐rich bottomset/basin‐floor deposits. Unit G is interpreted as part of a composite depositional sequence that records a change in basin margin style from an underlying incised slope with large sand‐rich basin‐floor fans to an overlying accretion‐dominated shelf with limited sand supply to the slope and basin floor. The change in margin style is accompanied with decreased clinoform height/slope and increased shelf width. This is interpreted to reflect a transition in subsidence style from regional sag, driven by dynamic topography/inherited basement configuration, to early foreland basin flexural loading. Results of this study caution against reconstructing basin margin successions from partial datasets without accounting for temporal and spatial physiographic changes, with potential implications on predictive basin evolution models.  相似文献   

Research Results on Ecological Hazard Objects in Abrosimov Bay (Novaya Zemlya,Kara Sea)     

Rimsky-Korsakov  N. A.  Flint  M. V.  Kazennov  A. Yu.  Anisimov  I. M.  Poyarkov  S. G.  Pronin  A. A.  Tronza  S. N. 《Oceanology》2020,60(5):625-632

Oceanology - The article presents results of field research on environmental assessment in Abrosimov Bay (Yuzhny Island of Novaya Zemlya) in connection with the existing RW disposal sites in this...  相似文献   

Palaeovalleys in foreland ramp settings: what happens as accommodation decreases down dip?          下载免费PDF全文

Rhodri M. Jerrett  Stephen S. Flint  Rufus L. Brunt 《Basin Research》2017,29(6):747-774

Recent advances in our understanding of palaeovalleys are largely guided by examples from passive margins, in which accommodation increases down depositional dip. This study tests these models against a dataset from the Pennsylvanian Breathitt Group of the central Appalachian foreland basin, USA. This fluvio‐deltaic succession contains extensive erosionally based fluvio‐estuarine sand bodies that can be tracked over 80 km down depositional dip from a proximal zone of high accommodation close to the orogenic margin to a distal, lower accommodation zone close to the cratonic margin of the basin. The sand bodies are up to 25 m thick, multi‐storey and characterized in their lower parts by strongly amalgamated storeys containing sandy fluvial to estuarine bar accretion elements, and in their middle to upper parts by more fully preserved storeys up to 10 m thick and laterally extensive over 100s of metres. The upper storeys include abandonment channel‐fills of heterolithic marine or marginal marine deposits or muddy to sandy point‐bar elements. Three major regional‐scale architectures include: (i) Tabular sand bodies that everywhere incise open marine prodelta and mouth bar facies and are interpreted as palaeovalleys formed during falling stage and lowstand systems tracts, when eustatic sea‐level fall outpaced tectonic subsidence across the entire study area. (ii) Sand bodies that incise genetically related floodplain lake and/or bay‐fill minor mouth bar deposits up depositional dip and open marine prodelta and mouth bar facies down dip. These stacked distributary channel deposits map down dip into palaeovalleys and formed when up dip subsidence rate resulted in positive, but reduced rate of accommodation creation, while lower tectonic subsidence rate down‐dip resulted in incision. (iii) Sand bodies that incise genetically related floodplain, lake and/or bay‐fill minor mouth bars up dip and pass down‐dip into genetically related unconfined floodplain, prodelta and mouth bar deposits. These sand bodies represent stacked distributary channel fills and channel amalgamation was the product of high rates of lateral migration, typical of the behaviour of channels above their backwater reach. Case (2) sand bodies demonstrate that in rapidly subsiding foreland basins, cross‐shelf palaeovalleys may form down depositional dip from aggradational, distributive fluival strata. Additionally, the genetic relationship between stacked distributary channels and palaeovalleys supports recent models for palaeovalley formation that emphasize diachronous, cut‐and‐fill during falling stage and lowstands of relative sea level.  相似文献   

Climate change influences on pollinator,forest, and farm interactions across a climate gradient     

Lee Hannah  Marc Steele  Emily Fung  Pablo Imbach  Lorriane Flint  Alan Flint 《Climatic change》2017,140(1):63-77

Improved cookstoves have been identified in Mexico as a key opportunity to advance sustainable local development priorities in disadvantaged regions while mitigating climate change. This paper reviews the Patsari Cookstove Project initiated in 2003 by an NGO, Interdisciplinary Group on Appropriate Rural Technology (GIRA). The project applied an interdisciplinary and participative user-centered approach to disseminate improved cookstoves in rural Mexico, with a special focus on indigenous and poor rural communities. To date, GIRA and the Patsari Network have disseminated thousands of stoves using a “training to trainers” model. Benefits from the project include tangible improvements in users’ health, as well as savings in time and money expended on fuelwood procurement and use. The project has also documented substantive environmental benefits from significant mitigation of greenhouse gas (GHG) emissions associated with traditional open fires. To sustain scaling up efforts over the long-term, two networks have been created: The Patsari Network, which includes several organizations promoting Patsari stoves for household users, and the Tsiri Network, which supports local food security and the empowerment of indigenous women through the promotion of institutional cookstoves. Through appropriately designed and implemented local interventions, the project demonstrates that the goals of advancing sustainable local development in rural areas and climate change mitigation may not be contradictory, and may in fact reinforce one another.  相似文献   

Terrorism and Counterterrorism: Geographic Research Questions and Agendas*   总被引：1，自引：0，他引：1  

Colin Flint 《The Professional geographer》2003,55(2):162-169

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Development of Quaternary stratigraphy in northeastern United States and adjacent Canada     

Richard Foster Flint 《Quaternary Research》1976,6(3):395-409

Quaternary stratigraphy in the northeastern region has developed slowly because researchers have been few and because quartzose bedrock and extensive forest have inhibited field study. The earliest stratigraphic studies antedated 1850, but in most parts of the region the stratigraphic units still recognized today were identified in the present century. Ancient and modern sequences are generalized and are shown in charts.  相似文献