Volcanic Scoria Research Articles

Lipid changes in cold hardened leaves of Nothofagus dombeyi

Changes in composition of various lipid fractions of leaves of the woody evergreen Nothofagus dombeyi hardened either under natural (at high and low altitude) or under laboratory conditions were determined. Frost hardiness of the leaves reached a maximum in the cold period (LT 5O) - 5° in the lowest place and - 10.2° in the highest site and was associated with an increase in phospholipids and galactolipids. Phosphatidylglycerol, digalactosyldiacylglycerols and monogalactosyldiacylglycerols increased in content by ca 200–400% in winter compared with the summer value. Phosphatidyl inositol concentration decreased in the high altitude samples over the same period. The unsaturation ratio of fatty acids in each lipid fraction was usually higher in summer than that in winter. The proportion of linolenic acid (mol%) of most lipid fractions with respect to the main fatty acids increased in the winter period at both low and high altitude sampling sites. It is possible that the higher proportion of this fatty acid in lipids could help to maintain the fluidity and function of membranes of N. dombeyi during cold stress. This and the accumulation of other described metabolites in this species could explain its pioneer capacity in areas formed by volcanic scoria exposed to strong frost even in summer.

Thermoluminescence dating of loess deposits at Plaidter Hummerich and its implications for the chronology of Neanderthal man.

Recent archeological investigations by the Forschungsstelle Altsteinzeit have shown that the crater hollows of extinct volcanoes in the Neuwied basin were regularly inhabited by Neanderthal man. A systematic search has yielded several sites, such as Plaidter Hummerich, T6nchesberg, the Wannen and the Wannenk6pfe, the Eiterk6pfe, and the Schweinskopf with a rich archeological ensemble related to the hunting activities of prehistoric man. At Plaidter Hummerich, much of this archeological material (bones and implements) has been found in situ in the loess beds that cap this volcano. We report here an absolute dating of these beds at Plaidter Hummerich based on recently developed thermoluminescence (TL) techniques [1, 2] for the dating of sediments. By virtue of the fact that these remains of Neanderthal man were found in situ, the loess TL ages provide perhaps a first absolute dating bracket (_<135000-80000a) to this developmental phase of mankind in the region. A date of 135000 a is also suggested for the recently discovered Kretzer tuff horizon in the Riss loess. The extinction of the Plaidter Hummerich volcano occurred ca. 240000 a ago [3]. At this stage, the crater summit was formed by a crater funnel surrounded by a steep wall of volcanic scoria. The infilling of the crater has continued since then, first in the form of crater rubble, derived from the rim, and subsequently by wind-blown loess. The entire sediment deposit (~15 m) is capped by the more recent (11000 a BP) Laacher See pumice [4]. Figures 1 and 2 provide a schematic diagram of the stratigraphy at the site. Loess ( < 9 m ) overlies the primary scoria and collapsed lava rubble. A still undescribed pumice, termed Kretzer tuff, subdivides this loess (Fig. 2, detail 1). On this loess a soil developed (weathered loess). The soil is separated from the overlying humus horizon ( < 2 m) by a calcified lava rubble or colluvium. The humus layer is inferred to correspond to the beginning of the Wfirmian [5] (Fig. 2, detail 2). A layer

Effect of N solution concentration, water rate and transient starvation on sweet paprika dry matter production and yield1

Abstract Sweet paprika response to water and nitrogen has not been reported in the literature, even though the crop is widely used in the food dyes industry. The objective of the present work was to determine the effects of water rate (IR), N concentration in water (CN), and transient starvation on total processable yield, yield quality and dry matter production and partitioning among fruits, leaves and stems. The experiment was carried out in 10‐liter pots filled with volcanic scoria and consisted of 4 × 3 IR × CN treatments plus 3 starvation treatments. In all treatments, about 95% of the total dry matter found in the tops of the plants was located in the fruits. Plants that gave good yields (100–120 and 170–210 g/plant high quality and total processable pods yield, respectively) were characterized at harvest time by 4.2–4.8% N in leaves, 1.8–1.9% N in fruits, 2% N in stems and 1.0–1.3% N in roots, and their total N consumption was 4.5–5.2 g/plant. Diminishing N application rates had only a small effect...

韓国，済州火山島の岩石学 Ｉ 岩石記載および総化学組成

Jeju Island is a shield volcano formed by successive central eruption, possibly from vents near Mt. Halla, during Upper Pliocene to Lower Pleistocene. It is mainly composed of large amounts of thick voluminous basaltic lava flows and minor pyroclastic rocks. Some hyaloclastites also occur along the coast. On the basis of topographical feature, which is in close connection with the volcanism, and geological evidence, the volcanism of this island can be classified into three stages; Lava plateau stage, Halla volcanic edifice stage and Volcanic scoria cones stage. Both Lava plateau stage and Halla volcanic edifice stage form a continuous series of the alkali basalt-trachyte association and of the hawaiite-trachyte one, respectively, and they also different from each other in the texture and constitutent minerals. The basic rocks in the former series are mostly microporphyritic and contain olivine phenocryst 10-15 percents, less than 2mm in size, while the basic rocks of the latter series are mostly macroporphyritic and contain plagioclase, pyroxene and olivine phenocrysts 25-50 percents, 5 to 10mm in size. Main constituent minerals of these rocks are plagioclase, olivine, augite, ferrosalite, anorthoclase and magnetite, and minor constitutent minerals are ilmenite, apatite, hedenbergite and kaersutite. They exhibit a restricted range of composition in each rock type. Chemical analyses of 63 volcanic rocks from both Lava plateau stage and Halla volcanic edifice stage are given. The analyses are plotted in several variation diagram; SiO2-total alkali, Na2O-K2O, normative feldspar, SI-oxide, A-F-M and K2O-oxide diagram. Rocks of both stages show a differentiation trend starting from nepheline-normative basaltic composition and leading to hypersthene normative and then to quartz-normative composition, and these rocks can be classified into alkali basalt, hawaiite, mugearite and trachyte by solidification index, main constituent minerals and their composition; alkali basalt ranges in SI from 42 to 35, hawaiite 35 to 15, mugearite 15 to 10, and trachyte 10-0.9. K2O-Na2O ratio of the basic rocks is between 1:3 to 1:2, except for a few specimens, and that of intermediate and acidic rocks is between 1:2 to 1:1. Normative plagioclases fall in the field of sodic series. A-F-M diagram shows a gradual trend toward alkali enrichment, with the curve rising closer to the iron apex. Intermediate lavas have higher total iron contents than alkali rocks in other areas such as Gough, Iki and Dogo. Both Lava plateau stage and Halla volcanic edifice stage show a very similar differentiation trend in the several diagrams. The above evidences support the view that all of the rock types in the island were derived from alkali olivine basalt magma, dominantly by process of crystallization differentiation.

Sorted stripes orientated by wind action: Some observations from sub‐antarctic marion island

AbstractSorted stripes found on the volcanic scoria and glacial deposits of sub‐Antarctic Marion Island indicate a distinct preferred orientation. Despite uniformity of slope and material, the stripes are predominantly aligned parallel to the wind. It is suggested that melting of needle ice by the early morning sun is of only limited importance in the sub‐Antarctic owing to the almost continual overcast conditions. The effect of the wind is so great that in exposed situations stripes are formed on horizontal surfaces.

The Atrisco Sites: Cochise Manifestations in the Middle Rio Grande Valley

Since the excavation of Bat Cave and the location of Cochise implements in situ along the banks of Wet Leggett Wash in western New Mexico, it has seemed likely that one or more of the Cochise periods might be represented in the Middle Rio Grande area where living conditions would have appeared very attractive to hunters and gatherers. In 1949 Bruce T. Ellis collected a series of artifacts, spalls, and cores in and along the surface of a wash in the Atrisco Grant, lying some 3 to 5 miles west of the city of Albuquerque. Most of the 72 possible implements were of such irregular and haphazard design that both Ellis and E. B. Sayles (who examined a representative group of specimens) felt that their identification as objects of human manufacture was open to considerable question. But the remaining group of pressure flaked blades and scrapers, the single point, a slab metate of volcanic scoria with slightly concave surface, and a number of one-handed grinding stones led to hope that further search might locate such materials in position, with the small manos, especially, suggesting Cochise affiliations.

Art. XIV.—On some Ancient Mounds of Scorious Ashes in Southern India

About the middle of 1836 I sent to the late Mr. J. Prinsep, then Secretary to the Asiatic Society of Bengal, a brief account of a hill of ashes, situate at Budigunta, about eleven miles W. from Bellary, in the Ceded Districts, which he published in the Journal of the Society for October of the same year under the head of “Note on the occurrence of Volcanic Scoria in the Southern Peninsula;”—a title given by himself to the communication, from which it may be inferred that he was inclined to consider the ashes (specimens of which were forwarded) as of volcanic origin.