...John Mysliwiec Conversations with the Earth November 29th, 2012 Volcanoes A volcano is a landform that generally is circular in cross-section that is constructed from lava and tephra erupted onto the Earth’s surface, usually the crust. The opening through which the lava and tephra are emitted is called the volcanic vent. Lava is magma that reaches the Earth’s surface. Magma is melted rock at high pressure and temperature. Magma rises because it is initially less dense than the rock surrounding rock. It eventually equals the density of the surrounding rock and becomes a magma chamber. Tephra is pumice or ash that is blown into the air during eruptions. Volcanoes are generally found where tectonic plates converge and diverge; but are usually not created where tectonic plates slide past one another. As a result volcanoes can be found in all sorts of climate locations. There are four primary types of volcanoes which all have varying effects on the environment. This paper will explore these various types of volcanoes and show how they differ, as well as giving examples of eruptions for each of the types discussed. Principle Types of Volcanoes Cinder cones: Cinder cones are built from particles and blobs of congealed lava ejected from a single vent; they are the simplest forms of volcanoes. Gas charged lava is violently blown into the air and breaks up into small fragments that solidify and fall as cinders around the vent to form a circular or oval...
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...Christine Burrill November 19, 2012 AA Flow Dynamics, Mauna Loa 1984 by Peter W. Lipman & Norman G. Banks I. Introduction The paper on ‘a’a flow dynamics written by Lipman and Banks is one of the first comprehensive studies regarding detailed observations of a long and complex ‘a’a lava flow. This paper was also one of the first to establish connections between lava flow morphology and changes in lava properties, specifically gas and crystal content. The flow that was studied was generated by the 1984 eruption along the northeast rift zone of Mauna Loa volcano, Hawaii (fig. 1). The major flow reached 27 km from the source vent after four days from the start of the eruption (Lipman and Banks, 1987). A decrease in the eruption rate, related to an increase in microphenocrysts and decrease in gas content of erupted lava, generated lava boats that blocked the flow. Blockages led to lava overflowing channel levees, redirecting the lava supply and leading to a stagnation of the major flow. The purpose of this paper is to summarize the key points from the study of the 1984 eruption, investigate some of the impacts this study has had on subsequent research and give a critical evaluation of the study. II. Major Points of Paper Flow Types Lipman and Banks (1987) observed distinctive types of ‘a’a that developed at certain distances from the vent, with certain changes in slope of the terrain and the way the flow advanced. The four types...
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...Dinosaur extinction is still a major mystery of earth history. In this review article, extinctions in the geological record will be briefly mentioned. Many of the imaginative theories for the extinction of the dinosaurs will also be presented. Within the uniformitarian paradigm, the meteorite impact theory, once considered ‘outrageous’, now is the dominant theory. However, the volcanic theory is still believed by a majority of paleontologists. Both theories have their strengths and weaknesses. The unscientific behavior of those involved in the meteorite paradigm change will be briefly explored. Evidence that the dinosaurs died in a cataclysm of global proportions will be presented, such as the huge water-laid dinosaur graveyards found over the earth. Occasional nonspecific bone-beds and the rarity of fossils of very young dinosaurs suggest a catastrophic death and burial. The billions of dinosaur tracks recently discovered provide testimony to unusual, stressful conditions. Nests, eggs, and babies are a challenge to a Flood model, but there are enough unknowns associated with the data that solid conclusions are difficult to draw. The part that impacts and volcanism play in a Flood paradigm will be briefly discussed. The question of whether the K/T boundary and the extinction of the dinosaurs should be considered a synchronous event within the Flood will be considered. Introduction Dinosaurs bring wonder to children and adults alike. That such great beasts once roamed the earth...
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...• English/US • Answers • Store • Outreach • Media • Kids • Education • Donate • Answers in Genesis • Answers • Animals • Dinosaurs • Dinosaur Extinction • The Extinction of the Dinosaurs The Extinction of the Dinosaurs by Michael J. Oard on August 1, 1997 Share: • • • • Originally published in Journal of Creation 11, no 2 (August 1997): 137-154. Shop Now First published: TJ (now Journal of Creation) 11(2):137–154 August 1997 by Michael J. Oard Dinosaur extinction is still a major enigma of earth history. In this review article, extinctions in the geological record will be briefly mentioned. Many of the imaginative theories for the extinction of the dinosaurs will also be presented. Within the uniformitarian paradigm, the meteorite impact theory, once considered ‘outrageous’, now is the dominant theory. However, the volcanic theory is still believed by a majority of palaeontologists. Both theories have their strengths and weaknesses. The unscientific behaviour of those involved in the meteorite paradigm change will be briefly explored. Evidence that the dinosaurs died in a cataclysm of global proportions will be presented, such as the huge water-laid dinosaur graveyards found over the earth. Occasional monospecific bone-beds and the rarity of fossils of very young dinosaurs suggest a catastrophic death and burial. The billions of dinosaur tracks recently discovered provide testimony to unusual, stressful conditions. Nests, eggs, and babies...
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...62118 0/nm 1/n1 2/nm 3/nm 4/nm 5/nm 6/nm 7/nm 8/nm 9/nm 1990s 0th/pt 1st/p 1th/tc 2nd/p 2th/tc 3rd/p 3th/tc 4th/pt 5th/pt 6th/pt 7th/pt 8th/pt 9th/pt 0s/pt a A AA AAA Aachen/M aardvark/SM Aaren/M Aarhus/M Aarika/M Aaron/M AB aback abacus/SM abaft Abagael/M Abagail/M abalone/SM abandoner/M abandon/LGDRS abandonment/SM abase/LGDSR abasement/S abaser/M abashed/UY abashment/MS abash/SDLG abate/DSRLG abated/U abatement/MS abater/M abattoir/SM Abba/M Abbe/M abbé/S abbess/SM Abbey/M abbey/MS Abbie/M Abbi/M Abbot/M abbot/MS Abbott/M abbr abbrev abbreviated/UA abbreviates/A abbreviate/XDSNG abbreviating/A abbreviation/M Abbye/M Abby/M ABC/M Abdel/M abdicate/NGDSX abdication/M abdomen/SM abdominal/YS abduct/DGS abduction/SM abductor/SM Abdul/M ab/DY abeam Abelard/M Abel/M Abelson/M Abe/M Aberdeen/M Abernathy/M aberrant/YS aberrational aberration/SM abet/S abetted abetting abettor/SM Abeu/M abeyance/MS abeyant Abey/M abhorred abhorrence/MS abhorrent/Y abhorrer/M abhorring abhor/S abidance/MS abide/JGSR abider/M abiding/Y Abidjan/M Abie/M Abigael/M Abigail/M Abigale/M Abilene/M ability/IMES abjection/MS abjectness/SM abject/SGPDY abjuration/SM abjuratory abjurer/M abjure/ZGSRD ablate/VGNSDX ablation/M ablative/SY ablaze abler/E ables/E ablest able/U abloom ablution/MS Ab/M ABM/S abnegate/NGSDX abnegation/M Abner/M abnormality/SM abnormal/SY aboard ...
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