Vertical-axis rotations and deformation along the active strike-slip El Tigre Fault (Precordillera of San Juan,Argentina) assessed through palaeomagnetism and anisotropy of magnetic susceptibility     

Fazzito  Sabrina Y.  Rapalini  Augusto E.  Cortés  José M.  Terrizzano  Carla M. 《International Journal of Earth Sciences》2017,106(2):631-657

International Journal of Earth Sciences - Palaeomagnetic data from poorly consolidated to non-consolidated late Cenozoic sediments along the central segment of the active El Tigre Fault...  相似文献   

Influences of temperature and nutrients on Synechococcus abundance and biomass in the southern Mid-Atlantic Bight   总被引：1，自引：0，他引：1  

Tiffany A. Moisan  Kristen L. Blattner  Carla P. Makinen 《Continental Shelf Research》2010

Synechococci are small (<1 μm) coccoid prokaryotes that play a significant ecological role in microbial food webs and are important contributors to carbon and nitrogen biogeochemical cycles. Under funding from NOAA and NASA, we developed a time series observatory to understand the seasonal variability of Synechococcus and other phytoplankton. Our goal is to understand the distribution and relative contribution of Synechococcus to the carbon cycle and how they relate to nutrients and temperature. Synechococcus in the southern Mid-Atlantic Bight exhibited a clear seasonal abundance pattern in both inshore and offshore waters—peaking in abundance (11×10⁴ cells ml⁻¹) during warm periods of summer. Synechococci were numerically important during periods of stratification when waters were warm and macronutrients were low. Using a simple algorithm to convert cellular volume to cellular carbon using image analysis, we estimated that Synechococcus cellular carbon ranged from 0.1 to 1.5 pg C per cell and was most significant compared to total particulate carbon in the summer peaking at ∼25% of the total carbon available. No direct correlations were found between Synechococcus abundance and nitrate, nitrite, ammonium, phosphate, and silicate. However, inshore Synechococcus abundance peaked at 10⁴ cells ml⁻¹ when nitrogen concentrations were lowest. Our results suggest that Synechococcus is adapted to warm temperatures and are capable of demonstrating rapid growth during summer when macronutrients are limiting. The ability of Synechococcus to take advantage of high summer temperatures, low nutrient concentrations and low light levels allows them to maintain a picoplankton community during periods of low detritus and nanophytoplankton is nutrient limited. Temperature-dependence is important in altering the size spectrum of the phytoplankton community and affects the carbon cycle on the Mid Atlantic Bight.  相似文献   

Geology, Geochemistry and Chromite Mineralization Potential of the Amnay Ophiolitic Complex, Mindoro, Philippines     

Graciano P. Yumul Jr  Ferdinand T. Jumawan    Carla B. Dimalanta 《Resource Geology》2009,59(3):263-281

The Amnay Ophiolitic Complex in Mindoro, the Philippines, is considered an emplaced Cenozoic South China Sea oceanic lithosphere as a result of the collision between the Palawan microcontinental block and the Philippine mobile belt. Middle Oligocene sedimentary rocks intercalated with dominantly MORB-like pillow lavas and volcanic flows suggest the generation of this ophiolite complex in an intermediate spreading ridge within a back-arc basin setting. The volcanic rock suite geochemistry also manifests a slab component suggesting that it is a supra-subduction zone ophiolite. Petrography of the gabbros shows a plagioclase-clinopyroxene crystallization order consistent with a back-arc basin setting. Spinel and pyroxene geochemistry shows that the lherzolites and aluminous-spinel harzburgites are products of low degrees of partial melting. The chromitites hosted by the harzburgites could have not been associated with the MORB-like volcanic suites, gabbros, lherzolites and aluminous-spinel harzburgites. The chromitites are products of mantle sources that have undergone higher degrees of partial melting that would have involved the presence of water. The study of this ophiolitic complex gives us a glimpse of the characteristics of the South China Sea.  相似文献   

BACI design reveals the decline of the seagrass Posidonia oceanica induced by anchoring     

Montefalcone M  Chiantore M  Lanzone A  Morri C  Albertelli G  Nike Bianchi C 《Marine pollution bulletin》2008,56(9):1637-1645

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Changes in seabed morphology, mud temperature and free gas venting at the Håkon Mosby mud volcano, offshore northern Norway, over the time period 2003–2006     

Jean-Paul Foucher  Stéphanie Dupré  Carla Scalabrin  Tomas Feseker  François Harmegnies  Hervé Nouzé 《Geo-Marine Letters》2010,30(3-4):157-167

The Håkon Mosby mud volcano is a 1.5-km-diameter geological structure located on the Southwest Barents Sea slope at a water depth of 1,270 m. High-definition seabed mapping of the mud volcano has been carried out in 2003 and 2006. A comparative analysis of the bathymetry and backscatter maps produced from the two surveys shows subtle morphological changes over the entire crater of the mud volcano, interpreted to be the consequence of mud eruption events. Mud temperature measurements point to a persistently warm mud at shallow depth in the crater. This is explained by upward fluid advection, rather than conductive cooling of mud flows. The small-scale spatial variability in the temperature distribution may be related to mud outflows or changes in the fluid flow regime. Furthermore, the locations of free gas venting observed in 2006 were found to differ from those of 2003. Our observations of overall similar topographic profiles across the mud volcano in 2003 and 2006 suggest that eruption events would have been modest. Nevertheless, the data bring evidence of significant change in activity even over short time intervals of only 3 years. This may be a characteristic shared by other submarine mud volcanoes, notably those considered to be in a quiescent stage.  相似文献   

Conservation genetics in aquatic species: General approaches and case studies in fishes and springsnails of arid lands     

Carla?Hurt  Philip?HedrickEmail author 《Aquatic Sciences - Research Across Boundaries》2004,66(4):402-413

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Toxicopathic liver lesions in English sole and chemical contaminant exposure in Vancouver Harbour,Canada     

Stehr CM  Myers MS  Johnson LL  Spencer S  Stein JE 《Marine environmental research》2004,57(1-2):55-74

The prevalence of toxicopathic liver lesions in English sole (Pleuronectes vetulus) was determined along a presumed gradient of chemical contamination in Vancouver Harbour, Canada. Fish were captured from five sites in or near Vancouver Harbour, British Columbia, Canada. No toxicopathic lesions were observed in fish examined at the reference site (Howe Sound outside Vancouver Harbour), or at the outer harbour site. In contrast, 20-23% of the fish from three sites located in the central harbour, Indian Arm and Port Moody Arm had one or more types of toxicopathic lesions. Likewise, aromatic hydrocarbon (AH) metabolites measured in bile exhibited a gradient in levels from lower concentrations at the reference site to significantly higher levels in fish from Indian Arm and Port Moody Arm harbour sites. The occurrence of toxicopathic liver lesions was statistically associated with concentrations of AHs measured in sediment and AH metabolite levels measured in bile.  相似文献   

A proposed format for geotechnical data     

Carla J. Potter 《Geo-Marine Letters》1982,2(3-4):243-246

Large quantities of raw geotechnical data presently exist in the individual collections of institutions and agencies throughout the world. In order to increase the usefulness of this vast amount of data to the scientific community, the National Geophysical Data Center (NGDC) intends to develop a comprehensive data bank for geotechnical information to be located at NGDC, along with a common format for the exchange of geotechnical information. This format would facilitate not only the transfer of geotechnical information between researchers, but also simplify the exchange and development of computer software with which to manipulate the data.  相似文献   

Zonation and Ecology of Epiphytic Hydroids in a Mediterranean Coastal Lagoon: The 'Stagnone' of Marsala (North-West Sicily)     

Stefano  Piraino Carla  Morri 《Marine Ecology》1990,11(1):43-60

Abstract. Distribution patterns of epiphytic hydroids of seagrass ( Posidonia occanica and Cymodocea nodosa ) beds were studied in the 'Stagnone', a moderately hypcrhaline lagoon in Sicily. The role of water movement in determining the spatial and temporal zonation of epiphytic hydroids and their morpho-physiological variations is evaluated. Remarks on systematics arc also included.  相似文献   

Estimation of the number density of fish from resonance absorptivity and echo sounder data     

Diachok  Orest; Liorzou  Bernard; Scalabrin  Carla 《ICES Journal of Marine Science》2001,58(1):137-153

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