6/29/2023 0 Comments Sequential parkThe comparative study demonstrated the sequential tests superiority over a broad range of alternatives. The results have been compared with those of popular EDF tests such as the Anderson-Darling, Cramer-von Mises, and Komogrov-Smirov tests. Large Monte Carlo simulation has been used to determine critical values and overall significance levels for all combinations of the two tests, and to conduct extensive power studies against a broad range of alternatives. Unlike the typical goodness of fit test, using parameter estimation methods such as maximum likelihood estimation and minimum distance estimation, this test using the two test statistics above does not involve a substantial degree of computational complexity. The test is accomplished by employing two new tests, sample skewness and sample kurtosis, sequentially as test statistics. The structural integrity of similarly extruded lobes highlights important hazard implications in regards to post-emplacement of such structures.This research presents a new sequential goodness of fit test for the three-parameter gamma distribution with a known shape. The Jumbles Avalanche provides an unprecedented opportunity to view the internal structure of a shear lobe. The more fluidal morphology and petrologic character of the Group 1 domes indicates they erupted at a much faster eruption rate than the Group 2 domes to develop a broad coulée. All of the field evidence indicates that the Group 2 domes were emplaced as ' shear lobes' as detailed in the early stages of the Soufrière Hills eruption (Watts et al., 2002). At one place on the edge of Dome C, a large block of cataclastic lava was also discovered with extreme stretching of plagioclase and hornblende crystals. Samples taken from a larger distance away had a texture of more typical massive, crystalline lava showing little evidence of deformation suggesting that overall the lava extruded predominantly along a thin zone of extreme deformation. Sampling from this surface and other points away from this surface highlighted the presence of highly fragmented lava with broken jigsaw-style phenocrysts up to one meter away from the smooth surface. On its upper surface, the remnants of a smooth semi-cylindical surface scored with striations is evident. The avalanche events left behind a near-vertical scarp composed of shattered, massive lava riddled with closely-spaced sigmoidal cooling joints to produce a very unstable ~250 meter high and ~300 meter wide metastable structure. This impressive deposit (total volume of ~7km2) spilled across the northeastern landscape focused away from the base of Dome C, one of the Group 2 domes. Following a period of quiescence, a series of 3 rock-fall avalanches, most likely triggered by a tectonic earthquake, collapsed away from one of the Group 2 domes to produce the 'Jumbles Avalanche' deposit. The age of emplacement of the Crags has been previously determined as between 1125 and 375 years B.P (Clynne & Muffler, 1989). Petrologically, the 2 Groups are very similar in whole-rock composition except there is a distinct difference in the amount of mafic inclusions present - that is ~2 vol% (Group1 domes) and ~10vol% (Group 2 domes). Group 2) are notably more dome-like, lacking lateral flow-features and any basal breccia but displaying steeper, blocky flanks and overall low Aspect Ratio. Group 1) exhibit a coulée-like appearance with asymmetric appearance, a thick, glassy basal breccia and distinct concentric flow ridges on the upper surface. Each of the domes is composed of a precarious pile of large angular lava blocks indicative of a relatively fast extrusion rate. The Chaos Crags are an aptly named and spectacularly well-preserved nest of 6 crystal-rich rhyodacitic lava domes that lie in the shadow of the renowned Lassen Peak in Lassen National Park, northern California.
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