Metallic Iron and Nickel in Cretaceous and Cenozoic Sediments: The Results of Thermomagnetic Analysis

Abstract

With the aid of thermomagnetic analysis (TMA) up to 800ºС the composition and distribution of particles of native iron and Fe-Ni alloy was studied in 15 sections, Gams (Austria), Verhorechie and Selbuhra (Crimea), Kvirinaki and Tetritskaro (Georgia), Aimaki, Bass, Dzhengutaj, Madzhalis and Gergebil (North Caucasus, Russia), Klyuchi and Tep-lovka (Volga Region, Russia), Koshak (Kazakhstan), Kara-Kala and Khalats (Turkmenistan). The age of sediments varies from Miocene to Early Cretaceous. Iron particles are present at 521samples out of 921studied. Their percentage varies from 10-5% to 0.05%. The distribution consists of two groups: 1) “zero” group (iron is not found by TMA); 2) group of logarithmic normal distribution with a differing modes. The global enrichment by iron particles in synchronous deposits of Miocene, Maastrichtian-Danian, Santonian and Cenomanian was discovered. With respect to nickel content, the iron particles fall into two groups: 1) nearly pure iron without nickel; and 2) iron with nickel content up to 20%, with modal value of 5%. The source of iron particles is the cosmic dust. Particles of pure nickel and the alloy containing more of 20% of nickel are very rare. Possibly, such particles are related mainly with impact events. A peak of elevated iron content with nearly constant nickel of 5-6% was found in almost all studied sections. It is a global effect which is not dependent of place and time of deposition of iron particles

Role of Acetylene in the Chemical Evolution of Carbon Complexity

“…Metal complexes that are used in laboratories and industry are rare in outer space, although iron-nickel particles are present in meteorites and likely in cosmic dust. 450 The dust particles are either carbonaceous (HACs, graphites, and PAHs) or silicate. Silicate grains consist mostly of pyroxene (MgSiO 3 ) and olivine (Mg 2 SiO 4 ).…”

“…The presence of catalytic species can provide a variety of pathways for the formation of aromatic systems. Metal complexes that are used in laboratories and industry are rare in outer space, although iron-nickel particles are present in meteorites and likely in cosmic dust . The dust particles are either carbonaceous (HACs, graphites, and PAHs) or silicate.…”

The history and state-of-the-art of the studies of native iron in terrestrial and extraterrestrial rocks

“…Так, содержание химических элементов (исключая водород и гелий) в фотосфере Солнца и в хондритах практически одинаково. Относительный объем ядра Земли составляет 12.6%, объем коры -1.4% от общего объема Земли, относительные «объемы» метеоритов: железные (ядро) -1.5% и каменные коровые (лунные и марсианские) -1.4% [Meteoritical Bulletin, 2000-2010. Таким образом, получается, что на долю ядра планет (железных метеоритов) приходится почти на порядок меньший объем, чем на долю земного ядра.…”

“…Тогда и возникла идея применить для массового изучения распространения частиц самородного железа ранее не применявшийся для этой цели термомагнитный анализ с нагревом до 800 °С. К настоящему времени накоплен достаточно большой объем данных о распространении частиц самородного железа в земных и внеземных породах и метеоритах [Антипин и др., 2014; Грачев и др., 2009; Марков и др., 2015; Мурдмаа и др., 2015; Печерский, 2008;2015;Печерский и др., 2006;2010;2011;2013;2017;2018;Печерский, Кузина, 2015;Печерский, Шаронова, 2012;2013;Цельмович и др., 2015;Grachev et al,2009;Pechersky, 2008;2010;Pechersky et al,2006;2010;и др. ].…”