北吕宋岛菲律宾活动带蛇绿岩及其上覆浊积岩的放射虫研究新进展     

Keisuke ISHIDA  Shigeyuki SUZUKI  Carla DIMALANTA  Graciano YUMUL JR.  Karlo QUEA?O  Decibel FAUSTINO-ESLAVA  Edanjarlo MARQUEZ  Noelynna RAMOS  Rolando PE?A 《地球学报》2012,33(S1):29-31

The basement of the Philippine Mobile Belt (PMB) is mainly composed of ophiolites that are mostly overlain by Paleogene to Miocene turbidites in central Luzon. To clarify the geological development of the PMB with respect to the initial stage of the arc volcanism (eg. Yumul et al., 2003, 2008; Dimalanta and Yumul, 2003; Suzuki et al., 2011), radiolarian dating was examined in siliceous sediments associated with the ophiolites and turbidites. The samples were collected from sites identified with the Zambales and Montalban ophiolites, basic tuff phyllites in NW Din-galan, and their overlying formations.  相似文献   

The logistics of household hurricane evacuation   总被引：1，自引：1，他引：0  

Michael K. Lindell  Jung Eun Kang  Carla S. Prater 《Natural Hazards》2011,58(3):1093-1109

Although there is a substantial amount of research on households’ hurricane evacuation decision making, there is much less research on the logistical issues involved in implementing those evacuations. The limited research on household evacuation logistics has consistently shown that most evacuees stay in the homes of friends and relatives or in commercial facilities rather than in public shelters. However, evacuation logistics—which can be defined as the activities and associated resources needed to reach a safe location and remain there until it is safe to return—encompasses a much broader range of behaviors than this. The present study extends previous research by reporting data on other aspects of evacuation logistics such as departure timing, vehicle use, evacuation routes, travel distance, shelter type, evacuation duration, and evacuation cost. Hurricane Lili evacuation data at the county level are generally consistent with the data from previous hurricanes, but there is notable variation across counties studied here. There were only modest correlations of demographic and geographic variables with the evacuation logistics variables, a result that indicates further research is needed to better understand what happens between the time an evacuation decision is made and the time re-entry is begun. Moreover, research is needed to understand the logistics of evacuation by special populations such as transients and households with disabled members.  相似文献   

The influence of citric acid,EDTA, and fulvic acid on U(VI) sorption onto kaolinite     

Michelle Barger  Carla M. Koretsky 《Applied Geochemistry》2011

Uranium(VI) sorption onto kaolinite was investigated as a function of pH (3–12), sorbate/sorbent ratio (1 × 10^?6–1 × 10^?4 M U(VI) with 2 g/L kaolinite), ionic strength (0.001–0.1 M NaNO₃), and pCO₂ (0–5%) in the presence or absence of 1 × 10^?2–1 × 10^?4 M citric acid, 1 × 10^?2–1 × 10^?4 M EDTA, and 10 or 20 mg/L fulvic acid. Control experiments without-solids, containing 1 × 10^?6–1 × 10^?4 M U(VI) in 0.01 M NaNO₃ were used to evaluate sorption to the container wall and precipitation of U phases as a function of pH. Control experiments demonstrate significant loss (up to 100%) of U from solution. Although some loss, particularly in 1 × 10^?5 and 1 × 10^?4 M U experiments, is expected due to precipitation of schoepite, adsorption on the container walls is significant, particularly in 1 × 10^?6 M U experiments. In the absence of ligands, U(VI) sorption on kaolinite increases from pH ～3 to 7 and decreases from pH ～7.5 to 12. Increasing ionic strength from 0.001 to 0.1 M produces only a slight decrease in U(VI) sorption at pH < 7, whereas 10% pCO₂ greatly diminishes U(VI) sorption between pH ～5.5 and 11. Addition of fulvic acid produces a small increase in U(VI) sorption at pH < 5; in contrast, between pH 5 and 10 fulvic acid, citric acid, and EDTA all decrease U(VI) sorption. This suggests that fulvic acid enhances U(VI) sorption slightly via formation of ternary ligand bridges at low pH, whereas EDTA and citric acid do not form ternary surface complexes with the U(VI), and that all three ligands, as well as carbonate, form aqueous uranyl complexes that keep U(VI) in solution at higher pH.  相似文献   

Eutrophication and salinization of urban and rural kettle lakes in Kalamazoo and Barry Counties,Michigan, USA     

Andrew MacLeod  Ryan Sibert  Christine Snyder  Carla M. Koretsky 《Applied Geochemistry》2011

Salinization and eutrophication caused by runoff of road salt and nutrients was assessed in three kettle lakes, two (Woods and Asylum Lakes) located in urban Kalamazoo, MI, and one (Brewster Lake) in rural Hastings, MI. Profiles of dissolved O₂, conductivity, pH, and temperature were measured in situ, at half meter intervals. Water samples were collected at discrete depth intervals of 1 m and analyzed for Fe(II), Mn(II), ammonium, alkalinity, Cl^?, Na, Mg, K and Ca. Results of this study indicate that all three lakes are eutrophic with anoxic bottom waters. Conductivity was much greater, and Cl^? levels were more than 100 times greater, in the two urban lakes compared to the rural lake, demonstrating the significant impact of road salt deicers on urban lake water chemistry.  相似文献   

Diurnal variation in relative photosynthetic performance of marestail (Hippuris vulgaris Linn.) Across a water temperature gradient using PAM fluorometry in Jiuzhaigou National Nature Reserve, Sichuan Province, China     

Carla BOSSARD 《山地科学学报》2011,8(6):794-807

This paper reports the first photosynthetic study of marestail in Jiuzhaigou. In this work, we used PAM fluorometry to examine photosynthetic rates of submerged and emerged marestail in three lakes. Three lakes were studied across a gradient of water temperature, with low water temperature conditions in Grass Lake and Arrow Bamboo Lake, and higher water temperature in Five Colored Lake. In the field, electron transport rates (ETR_max) were measured as rapid light curves (RLCs) by in situ yield measurements. Submerged and emerged marestail showed higher photosynthetic activity in Five Colored Lake compared to the other lakes, a response consistent with the adaptation of marestail in Five Colored Lake to high water temperature. The optimal temperature for photosynthesis of submerged marestail in Jiuzhaigou was about 12 °C. Nonphotochemical quenching (NPQ) of submerged and emerged marestail increased with increasing water temperature. Maximum quantum yield (F _v/F _m) of submerged marestail in Five Colored Lake showed full recovery at 1700 h due to higher NPQ. Further, the chlorophyll a for submerged marestail was the highest in Grass Lake and the lowest in Five Colored Lake. These results indicate that in different lakes the function of these aquatic plants is associated with a diversity of place-dependent environmental conditions, especially water temperature that leads to pronounced differences in the plant’s ecophysiological reactions.  相似文献   

Effects of the 'Prestige' oil spill on macroalgal assemblages: large-scale comparison     

Lobón CM  Fernández C  Arrontes J  Rico JM  Acuña JL  Anadón R  Monteoliva JA 《Marine pollution bulletin》2008,56(6):1192-1200

An assessment of the effects of the 'Prestige' oil spill on intertidal, macroalgal assemblages was carried out comparing abundance data obtained before and after the spill. Four zones in the North and Northwest coast of Spain were sampled, one of them located at the immediate vicinity of the spill, the zone most heavily oiled. Macroalgal assemblages had similar structure between years. Neither critical decrease in abundance of the dominant macroalgae, nor increase in opportunistic species were found. Some differences in abundance were observed, but they did not show any pattern, being more likely the result of the natural variability of the assemblage. Extensive, but not intense fuel deposition on the shores and a limited use of aggressive cleanup methods are suggested as possible causes for the lack of the effects in these assemblages after the 'Prestige' oil spill.  相似文献   

Crustal thickness and adakite occurrence in the Philippines: Is there a relationship?     

Carla B. Dimalanta  Graciano P. Yumul  Jr 《Island Arc》2008,17(4):421-431

Adakites are increasingly being recognized worldwide in a variety of tectonic settings. Models on the formation of this geochemically distinct class of volcanic rocks have evolved from partial melting of subducted young, hot oceanic slabs to magmatism resulting from oblique subduction, low‐angle or flat subduction, or even slab‐tearing. Some workers have also pointed to the partial melting of thickened crust to explain the generation of adakitic melts. Rare earth element ratios from adakites and adakitic rocks in the Philippines were used in this study to obtain approximations of the levels where they were generated. These were tied to available geophysical data that defines the crustal thickness of the areas where the samples were collected. High Sm/Yb and La/Yb ratios denote the involvement of amphiboles, and in some cases garnet, in the generation of adakites and adakitic magmas. The presence of amphibole and garnet as residual phases suggests high pressures corresponding to thicker crust (～30 to 45 km). Adakites and adakitic rocks formed through processes other than melting of subducted young oceanic crust would need ≥30 km to account for the heavy rare earth element signatures. If mantle fractionation is not the process involved, crustal thickness is critical to generate adakites and adakitic rocks.  相似文献   

Buruanga peninsula and Antique Range: Two contrasting terranes in Northwest Panay,Philippines featuring an arc–continent collision zone     

Lawrence R. Zamoras  Mary Grace A. Montes  Karlo L. Queaño  Edanjarlo J. Marquez  Carla B. Dimalanta  Jillian Aira S. Gabo  Graciano P. Yumul Jr. 《Island Arc》2008,17(4):443-457

Alternating chert–clastic sequences juxtaposed with limestone blocks, which are units typical of accretionary complexes, constitute the Buruanga peninsula. New lithostratigraphic units are proposed in this study: the Unidos Formation (Jurassic chert sequence), the Saboncogon Formation (Jurassic siliceous mudstone–terrigenous mudstone and quartz‐rich sandstone), the Gibon Formation (Jurassic(?) bedded pelagic limestone), the Libertad Metamorphics (Jurassic–Cretaceous slate, phyllite, and schist) and the Buruanga Formation (Pliocene–Pleistocene reefal limestone). The first three sedimentary sequences in the Buruanga peninsula show close affinity with the ocean plate stratigraphy of the North Palawan terrane in Busuanga Island: Lower–Middle Jurassic chert sequences overlain by Middle–Upper Jurassic clastics, juxtaposed with pelagic limestone. Moreover, the JR5–JR6 (Callovian to Oxfordian) siliceous mudstone of the Saboncogon Formation in the Buruanga peninsula correlates with the JR5–JR6 siliceous mudstone of the Guinlo Formation in the Middle Busuanga Belt. These findings suggest that the Buruanga peninsula may be part of the North Palawan terrane. The rocks of the Buruanga peninsula completely differ from the Middle Miocene basaltic to andesitic pyroclastic and lava flow deposits with reefal limestone and arkosic sandstone of the Antique Range. Thus, the previously suggested boundary between the Palawan microcontinental block and the Philippine Mobile Belt in the central Philippines, which is the suture zone between the Buruanga peninsula and the Antique Range, is confirmed. This boundary is similarly considered as the collision zone between them.  相似文献   

Influence of ambient flow around the horseshoe crabLimulus polyphemus on the distribution and orientation of selected epizoans     

Joanne Dietl  Carla Nascimento  Richard Alexander 《Estuaries and Coasts》2000,23(4):509-520

Cumulatively scored distributions of the slipper shell gastropodCrepidula sp., the sand-building polychaete wormSabellaria vulgaris, the calcareous meandering tubed polychaeteFilograna implexa, the barnacleSemibalanaus balanoides, and the lacy bryozoanSchizoporella sp. were mapped on a cm-square gridded silhouette of the prosoma, opisthosoma, and movable spines, and telson of the horseshoe crabLimulus polyphemus stranded on Reeds Beach, Cape May County, New Jersey in the Delaware Bay. Statistically tested and contoured epizoan frequencies for 81 males and 59 females revealed that slipper shells and agglutinated worm tubes are concentrated near the movable spines on the opisthosoma, but rare on recessed chilarial or opercular pleurites, the prosoma, and telson. Barnacles are disproportionately concentrated in entapophyseal pits on the opisthosoma and in the longitudinal furrows flanking the cardiac lobe of the prosoma. Bryozoans are concentrated near movable marginal spines of the opisthosoma, but also found on all areas of the prosoma, opisthosoma, and hinge area in between, as well as the telson. Different morphologic sites for their respective modal concentrations may result from competitive exclusion of bryozoans by barnacles. Genal angles have lower statistically predicted frequencies of bryozoans, barnacles, and sand worm tubes. Apertural openings of calcareous tubes are predominantly posteriorly oriented whereas the anterior magin of slipper shells are randomly oriented on the opisthosoma. Eschewing differential mortality, nonrandom distributions indicate possible: rugophilic (groove-seeking) larval settlement behavior for barnacles that preferred the recessed hinge area, longitudinal grooves, and pits; rheophilic (current-seeking) larval settlement behavior for the gastropods and tube-building polychaetes that filter feed in the eddies generated near the movable spines of the downcurrent-sloping opisthosoma; and geotactic (gravity-influenced) larval settlement or post-settlement migration to the vaulted crest (cardiac lobe). Deficiencies of protruding epizoic skeletons on the genal angles and anterior margin of the host may be due to removal by abrasion as the horseshoe crab plowed through sediment or shearing of the epizoans from the carapace substratum in strong currents or waves.  相似文献   

Adakitic lavas in the Central Luzon back‐arc region,Philippines: lower crust partial melting products?   总被引：6，自引：0，他引：6  

Graciano P. Yumul JR    Carla Dimalanta  Herve Bellon  Decibel V. Faustino  Joel V. De Jesus  Rodolfo A. Tamayo  JR    Ferdinand T. Jumawan 《Island Arc》2000,9(4):499-512

Abstract Volcanism in the back-arc side region of Central Luzon, Philippines, with respect to the Manila Trench is characterized by fewer and smaller volume volcanic centers compared to the adjacent forearc side-main volcanic arc igneous rocks. The back-arc side volcanic rocks which include basalts, basaltic andesites, andesites and dacites also contain more hydrous minerals (ie, hornblende and biotite). Adakite-like geochemical characteristics of these back-arc lavas, including elevated Sr, depleted heavy rare earth elements and high Sr/Y ratios, are unlikely to have formed by slab melting, be related to incipient subduction, slab window magmatism or plagioclase accumulation. Field and geochemical evidence show that these adakitic lavas were most probably formed by the partial melting of a garnet-bearing amphibolitic lower crust. Adakitic lavas are not necessarily arc–trench gap region slab melts.  相似文献