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Full-Text Articles in Physical Sciences and Mathematics
Methanesulfonate In The Firn Of King George Island, Antarctica, Jiankang Han, Zichu Xie, Xinping Zhang, Dongsheng Dai, Paul Andrew Mayewski, M. S. Twickler
Methanesulfonate In The Firn Of King George Island, Antarctica, Jiankang Han, Zichu Xie, Xinping Zhang, Dongsheng Dai, Paul Andrew Mayewski, M. S. Twickler
Earth Science Faculty Scholarship
Methanesulfonate was investigated as a potential contributor to the sulfur budget, based on analysis of a firn core from Collins Ice Cap, King George Island, Antarctica (62°10' S, 58°50' W). The anion was found to be present at a mean concentration of 0.17 μeq L-1, with a maximum of 0.73 μeq L-1. Dating based on the δ18O profile suggests that the principal peaks of methanesulfonate are associated with snow deposited in summer and autumn. A careful examination of MSA, SO42-and nssSO42- profiles indicates that two of the three peaks …
High-Precision Dating Of Volcanic Events (A.D. 1301–1995) Using Ice Cores From Law Dome, Antarctica, Anne S. Palmer, Tas D. Van Ommen, Mark A. J. Curran, Vin Morgan, Joe M. Souney, Paul Andrew Mayewski
High-Precision Dating Of Volcanic Events (A.D. 1301–1995) Using Ice Cores From Law Dome, Antarctica, Anne S. Palmer, Tas D. Van Ommen, Mark A. J. Curran, Vin Morgan, Joe M. Souney, Paul Andrew Mayewski
Earth Science Faculty Scholarship
A record of volcanic activity over the period A.D. 1301–1995 has been extracted from three Law Dome ice cores (East Antarctica). The record dating is unambiguous at the annual level from A.D. 1807 to 1995 and has an uncertainty of ±1 year at A.D. 1301. Signals from 20 eruptions are preserved in the record, including those of two unknown eruptions with acid deposition beginning in A.D. 1810.8 and A.D. 1685.8. The beginning of the ice core signal from the A.D. 1815 Tambora eruption is observed in the austral summer of A.D. 1816/1817. The mean observed stratospheric transport and deposition time …
Post-Collisional Magmatism On The Northern Margin Of The Taurides And Its Geological Implications: Geology And Petrology Of The Yahyalı-Karamadazı Granitoid, Gonca Gençali̇oğlu Kuşcu, M. Cemal Göncüoğlu, İlkay Kuşcu
Post-Collisional Magmatism On The Northern Margin Of The Taurides And Its Geological Implications: Geology And Petrology Of The Yahyalı-Karamadazı Granitoid, Gonca Gençali̇oğlu Kuşcu, M. Cemal Göncüoğlu, İlkay Kuşcu
Turkish Journal of Earth Sciences
The Karamadazı Granitoid (Yahyalı-Kayseri) is a typical example of bimodal magmatism on the northern margin of the Eastern Tauride belt. The Karamadazı Granitoid intrudes the Palaeozoic-Mesozoic Yahyalı metamorphic rocks and is unconformably overlain by Upper Maastrichtian clastics. It consists of granodiorite-quartz diorite as the main intrusive phase, and includes leucogranites and aplitic dykes in its marginal parts. Samples from the Karamadazı Granitoid are calc-alkaline and calcic in character. The granodiorites are mainly metaluminous, whereas leucogranites and aplites are weakly peraluminous in nature. Plots of major-element oxides against SiO2 indicate a poor fractionation trend for the granodiorites. The leucogranites represent highly …
Stratigraphy, Geochemistry And Depositional Environment Of The Celestine-Bearing Gypsiferous Formations Of The Tertiary Ulaş-Sivas Basin, East-Central Anatolia (Turkey), Erdoğan Teki̇n
Turkish Journal of Earth Sciences
Celestine-bearing evaporite mineralization is widespread in the Tertiary evaporitic units of the Ulaş-Sivas Basin, east-central Anatolia. The oldest deposition of gypsum, which is of laminated character, occurred in a shallow inner-lagoonal environment or in depressions during Late Eocene regression. Thick gypsum and overlying beds composed of alternating bedded, nodular gypsum and sandstone developed in coastal sabkhas and abandoned channels within a meander-river complex during Oligocene time. The last occurrence of evaporitic units, namely massive and bedded gypsum alternating with sandstones and fossiliferous limestones, resulted from limited marine transgression of an Early Miocene sea along the southern margin of the Sivas …
Tectonic Implications Of Some Cretaceous Pillow Basalts From The North Anatolian Ophiolitic Mélange(Central Anatolia-Turkey) To The Evolution Of Neotethys, Bora Rojay, Kenan M. Yaliniz, Demi̇r Altiner
Tectonic Implications Of Some Cretaceous Pillow Basalts From The North Anatolian Ophiolitic Mélange(Central Anatolia-Turkey) To The Evolution Of Neotethys, Bora Rojay, Kenan M. Yaliniz, Demi̇r Altiner
Turkish Journal of Earth Sciences
The most widespread blocks within the North Anatolian ophiolitic mélange of central Anatolia (Turkey) are ophiolitic fragments, Jurassic-Cretaceous carbonate blocks and pillow basalts. The blocks of pillow basalts have an immobile trace-element geochemistry that is characteristic of ocean-island alkali basalts. An N-MORB-normalized spider diagram shows a distinctive enrichment of most incompatible trace elements and exhibits a far greater range of absolute abundances than N-MORB. Selected incompatible-element contents and ratios of basalts show high Ba/Nb (~8),low Zr/Nb(~5)and low La/Nb(~0.5)relative to N-MORB. The presence of thin-shelled \"Protoglobigerina\" and Cadosina associated with miliolids and epistominid foraminifers indicates that the age of the pink …
Origin Of Late Quaternary Dune Fields On The Southern High Plains Of Texas And New Mexico, Daniel R. Muhs, Vance T. Holliday
Origin Of Late Quaternary Dune Fields On The Southern High Plains Of Texas And New Mexico, Daniel R. Muhs, Vance T. Holliday
United States Geological Survey: Staff Publications
Mostly stabilized late Holocene eolian sands on the Southern High Plains of the United States were studied to determine their origins and to assess whether present dune stability depends more strongly on sediment supply, sediment availability, or transport limitations. Geomorphic, sedimentological, and geochemical trends indicate that late Holocene dunes formed under westerly paleowinds, broadly similar to those of today. Mineralogical and geochemical data indicate that the most likely source for the sands is not the Pecos River valley, but the Pleistocene Blackwater Draw Formation, an older, extensive eolian deposit in the region. These observations suggest that new sand is supplied …