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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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   

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   

Spatial Variability in Hydrologic Properties of a Volcanic Tuff     

J. D. Istok  C. A. Rautman  L. E. Flint  A. L. Flint 《Ground water》1994,32(5):751-760

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Pahoehoe and aa in Hawaii: volumetric flow rate controls the lava structure     

Scott K Rowland  George PL Walker 《Bulletin of Volcanology》1990,52(8):615-628

The historical records of Kilauea and Mauna Loa volcanoes reveal that the rough-surfaced variety of basalt lava called aa forms when lava flows at a high volumetric rate (>5–10 m³/s), and the smooth-surfaced variety called pahoehoe forms at a low volumetric rate (<5–10 m³/s). This relationship is well illustrated by the 1983–1990 and 1969–1974 eruptions of Kilauea and the recent eruptions of Mauna Loa. It is also illustrated by the eruptions that produced the remarkable paired flows of Mauna Loa, in which aa formed during an initial short period of high discharge rate (associated with high fountaining) and was followed by the eruption of pahoehoe over a sustained period at a low discharge rate (with little or no fountaining). The finest examples of paired lava flows are those of 1859 and 1880–1881. We attribute aa formation to rapid and concentrated flow in open channels. There, rapid heat loss causes an increase in viscosity to a threshold value (that varies depending on the actual flow velocity) at which, when surface crust is torn by differential flow, the underlying lava is unable to move sufficiently fast to heal the tear. We attribute pahoehoe formation to the flowage of lava at a low volumetric rate, commonly in tubes that minimize heat loss. Flow units of pahoehoe are small (usually <1 m thick), move slowly, develop a chilled skin, and become virtually static before the viscosity has risen, to the threshold value. We infer that the high-discharge-rate eruptions that generate aa flows result from the rapid emptying of major or subsidiary magma chambers. Rapid near-surface vesiculation of gas-rich magma leads to eruptions with high discharge rates, high lava fountains, and fast-moving channelized flows. We also infer that long periods of sustained flow at a low discharge rate, which favor pahoehoe, result from the development of a free and unimpeded pathway from the deep plumbing system of the volcano and the separation of gases from the magma before eruption. Achievement of this condition requires one or more episodes of rapid magma excursion through the rift zone to establish a stable magma pathway.  相似文献   

Multivariate Geostatistïcal Analysis of Ground-Water Contamination: A Case History     

Jonathan D. Istok  Jeffrey D. Smyth  Alan L. Flint 《Ground water》1993,31(1):63-74

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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   

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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Application of Deuterium Excess for Identification of Freshwater Sources in the Bays of Novaya Zemlya Archipelago     

Kossova  S. A.  Dubinina  E. O.  Miroshnikov  A. Yu.  Flint  M. V. 《Doklady Earth Sciences》2019,487(1):827-830

Doklady Earth Sciences - An isotopic–geochemical study was carried out for waters of Tsivolkii and Sedov bays (southeastern coast of the Novaya Zemlya Archipelago). The waters of these bays...  相似文献   

Vertical Variability of Primary Production and Chlorophyll a in the Kara Sea in the Middle of Summer: Contribution of Subsurface Maxima to the Water Column Values     

Demidov  A. B.  Gagarin  V. I.  Eremeeva  E. V.  Artemiev  V. A.  Polukhin  A. A.  Shchuka  S. A.  Grigoriev  A. V.  Khrapko  A. N.  Flint  M. V. 《Oceanology》2021,61(5):645-661

Oceanology - Spatial and vertical variability of primary production (PP) and Chl a were studied in the framework of the 76th cruise of R/V Akademik Mstislav Keldysh to the Kara Sea from July 7 to...  相似文献