Meteorite craters, volcanoes and deep valleys are main obiects of Mars topography. The are many tausend or millions of craters and they are very different, with diameters of only centimeters to big basins with diameters of 25oo kilometers. The age of oldest craters on Mars is about 3,9 billions year.
A palynological study of recent sediments from Ijora Creek, an Urban Creek in Lagos, Southwestern Nigeria was carried out to provide inferences on paleovegetation and climate change over time in the study area. Two stations 90m apart were sampled at low tide in a boat using a Russian peat corer. Samples were taken at 10cm intervals and eighteen sediments samples were collected and processed using standard palynological methods. Two hundred and sixty six (266) and two hundred and thirty three (231) palynomorphs were recovered from stations 1 and 2 respectively. Palynomorphs recovered and identified to species level include Alchornea cordifolia, Hymenocardia acida, Elaeis guineensis, Spathodea companulata, Triumfetta pentandra, Uapaca acuminata, Tridax procumbens, Berlinia sp., Eugenia sp., Celtis sp., Albizia sp., Cyperus sp. together with species of Poaceae, Asteraceae, Arecaceae, Eurphorbiaceae, Acanthaceae, with common microforaminiferal test linings and fungal spores. Poaceae and fungal spores dominated the assemblage while station 1 recorded the highest pollen and spore abundance. The presence of microforaminiferal wall linings, fungal spores and the freshwater swamp species Alchornea cordifolia and the oil palm pollen Elaeis guineensis suggests a dominantly wet period in which, there was a marked marine transgression into the creek, interrupted occasionally by dry climate as inferred from the abundant records of Poaceae and Asteraceae. The presence of secondary forest species especially Elaeis guineensis suggests the impact of human activities on the paleovegetation.
Carbonaceous chondrite NWA 4967 was investigated by confocal Raman micro-spectroscopy. Olivine (Fa0-68), orthopyroxene with high En95-100 and low enstatite content En25-58, clinopyroxene, plagioclase, withlockite, cristobalite, coesite, graphite and diamond have been identified and characterized. Two groups of olivines have been detected: one with high Fo content Fo80-100 and another with relatively high Fa content Fa30–68. Diamond is common and exhibits the wide range of Raman shift between 1298 and 1339 cm–1 with dominant peak at 1332 cm–1 as in the case of terrestrial diamonds. Distributions of Raman peaks for olivines and carbon phases have been analyzed.
The article presents the person Ignacy Horodecki, the professor of the mineralogy at The University of Vilnius. Prof. I. Horodecki was interested in meteorites. He studied meteorites Brahin, Zaborzika and Lixna. He led the scientific correspondence on the subject of meteorites with the French scientist Alexander Brongniart. He passed on Polish meteorites to investigations to the superb chemist A. Laugier. Prof. Horodecki introduced meteorites to the didactics.
Morasko meteorite (IAB octahedrite) contains numerous graphite-troilite inclusions. Within these inclusions, many mineral phases have been found, including native elements, sulphides, tellurides, oxides, phosphates and silicates. Apart from dominant graphite and troilite, the following minerals occur: copper, sphalerite, daubreelite, chromite, cosmochlor, enstatite, albite and orthoclase; phosphates (buchwaldite and brianite) are found occasionally, whereas djerfischerite, altaite, olivine and silica are rare. The mineral composition of the nodules suggests a more complex origin of the Morasko-type meteorites than currently assumed.
Trynitite is a material in form of a glass created as a result of a nuclear explosion close to ground. The mechanism of its formation is similar to the formation of impact glasses and tektites, although the material usually contains trapped bubble voids, much more water and it is radioactive. High resolution non-destructive gamma spectrometry technique was used to measure rdionuclides in the chips of trinitities. The signals were detected for 137Cs, 152Eu, 226Ra, 241Am and 133Ba. The most extreme concentration was found for cesium 137Cs which the specific activity reached the level of 2317 mBq/g. Much lower values were obtained for 241Am – 722 mBq/g, 152Eu – 211 mBq/g, 226Ra – 451 mBq/g and 133Ba – 94 mBq/g.
Average molecular weight and average atomic number of molecule of Jezersko ordinary chondrite (H4 S2(3) W2, find in 1992 in Slovenia) have been calculated using literature data on chemical composition of the meteorite (Miler et al. 2014). It was shown that Jezersko’s = 55.58, = 27.21, and ratio / = 2.043 for composition without water. Jezersko’s silicates shown the values: = 54.08, = 21.77, and / = 2.484. Volume and radius of average Jezersko molecule, and of atom have been also determined. It was calculated that the average volume of Jezersko’s molecule Vmol = 2.515·10–29 m3, and average radius of Jezersko’s molecule Rmol = 181.5 pm. Average volume of the Jezersko’s atom Vatom = 1.117·10–29 m3, and average radius of Jezersko’s atom: Ratom = 138.5 pm. Ratio of average Jezersko’s volume of molecule to atom volume: 2.25, and ratio of radius of molecule to radius of atom: 1.31. Number of atoms in Jezersko meteorite average molecule Nmol = /Amean = /Zmean = 2.25, and for Jezersko’s silicates Nsimol = 2.48.
Ordinary chondrite NWA 4047 was investigated by confocal Raman microspectroscopy to identify the extraterrestrial minerals. Olivines, orthopyroxenes, clinopyroxenes, plagioclase, graphite and diamond have been identified and characterized.
The article presents information about Białystok meteorite (1827). The meteorite consisted of many fragments, but only several became found. Jan Wolski collected information about the phenomenon. Wolski was the teacher of physics at grammar-school in Białystok. The exact investigations of the strewn field were not executed. The Białystok meteorite was forgotten stay on many years.
Impacts geology is a multi-disciplinary science, focus aspects of meteoritics, astronomy, petrography, geochemistry, structural geology, sedimentology and geophysics. The first studies of craters began in the 60s. Significant events in the development of this science were: the first research of the Cosmos, development of mineralogical and geochemistry analysis and important papers. Significant progress in the development of research studies reflect the number of newly discovered craters. Many aspects associated with them, such as dating, strewnfields, water impacts are still fairly problematic.
In the 1960s demonstrated that the Ries-Steinheim craters, located in the south of Germany and tektites types moldavites are the same age. Ries crater strewnfield covers eastern Germany, the Czech Republic and northern Austria. A few old scientific studies have not given a clear answer about model creation and the actual size of moldavite strewnfield. For this reason 11 years ago created a model that was to clarify these issues.
It seems that the only correct way to identify impact craters is a combination of theoretical analysis, visual observation and experimental analysis, which are inextricably linked to the environment in which the crater was formed. Undoubtedly, the shock metamorphism is an essential diagnostic tool for the identification of the crater. The depth of water is a major problem in the formation of the marine craters.
Abstract: This article is appeared a problem of meteorites classification and tried to connect interpretation and explanation of other phenomenon which are situated on the border between science and fiction. The conventional classification of meteorites indexed them as: (1) stony meteorites, (2) stony-iron meteorites and (3) iron meteorites. The matter of the Solar System could have various forms and its very varied in relation according to their physical, chemical and mineralogical aspects. In compliance with the above, the author tried to extend the classification by added e.g. ice meteorites, which are recognized in Russian literature. Sometimes others, not classified phenomenon are described as “colorful rains”, “jelly matter”, gas-dust objects or sudden, local darkness. As an evidences that could confirm the main theses of the author, an examples of literature are quoted. All of them should be supported by science investigations which are limited by rare frequency of the phenomena occurrence. By better description of small and different portions of cosmic matter, we could understand the Solar System and its laws.
In the middle of June 1927 a few inhabitants of the village of Gaj (10 km from Wyszków; central Poland) witnessed a meteorite fall. The solid fell into a swamp, which made searching for it very difficult. Searching work was held in the years 1957-1958, 1981-1982, 1990 and 1996. Present searching, which was started in 2005, still has not led to the meteorite finding.
Land cover change analysis between 1997 and 2016 was conducted in Oddusuddan Divisional Secretariat, Mullaitivu District, using remote sensing and geographic information system incorporated with field verifications. Various Satellite images and different digital maps have been used for extracting information. The overall objective of this study was to detect the magnitude of land cover change in Oddusuddan between 1997 and 2016. The methodology of this study was a change detection analysis of satellite imagery with Landsat ETM data. Two dates of Landsat image data of the 1997 and 2016 were used to produce a land cover map. The Maximum Likelihood algorithm was used for supervised classification to detect changes for twenty years. The result showed that during the last twenty years, the forest cover declined from 453.02 km2 in 1997 to 447.14 km2 in 2016. It was noticed that socio-economic factors were the major driving forces for the land cover change.
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