https://par.nsf.gov/servlets/purl/10107309

ShengBTE: A solver of the Boltzmann transport equation for phonons ☆

The composition of the primitive mantle derived here shows that Earth was assembled from material that shows many of the same chemical fractionation processes as chondritic meteorites. These processes occurred at the initial stage of the solar system formation, under conditions thought to be present in the solar nebula. But the stable isotope record excludes chondritic meteorites as the ‘building blocks’ of Earth. Meteorites formed in local environments separated from that part of the inner solar system where much of the material forming the terrestrial planets was sourced.

https://booksite.elsevier.com/brochures/treatiseongeochemistry/contents/sample2.pdf

Cosmochemical Estimates of Mantle Composition

Condensation in the primitive solar nebula

List of illustrations Preface 1. The relevance of archaeological history 2. Classical archaeology and antiquarianism 3. The beginnings of scientific archaeology 4. The imperial synthesis 5. Culture-historical archaeology 6. Soviet archaeology 7. Functionalism in Western archaeology 8. Neo-evolutionism and the New Archaeology 9. The explanation of diversity 10. Archaeology and its social context Bibliographical essay References Index.

A History of Archaeological Thought

Ca isotope fractionation on the Earth and other solar system materials

TWO well known atomic arrangements found among tetrahedrally co-ordinated AX compounds such as silicon carbide (SiC) and zinc sulphide (ZnS) are those based on a cubic close-packed array or on a hexagonal close-packed array of tetrahedra. The two polymorphs are generally designated as the sphalerite and wurtzite types, respectively, from their occurrence in zinc sulphide. The crystal structures of the Group IV elements, carbon, silicon, germanium and α-tin, are based on the cubic close-packed sphalerite arrangement (aside from graphite, tetragonal tin and tetragonal germanium) with all A and X sites occupied by the same kind of atom. The existence of polymorphs analogous to wurtzite among these elements is not surprising, because the two types of structure are so similar geometrically that the energy differences between them must be small. A wurtzite-like polymorph of silicon has already been synthesized1. For carbon a rhombohedral polymorph called beta-diamond, which corresponds to the 3R polytype of wurtzite, has been reported as birefringent lamellae in terrestrial diamonds2,3. The synthesis of a hexagonal wurtzite polymorph of diamond by shock conversion of graphite has been disclosed in a patent application4. A substance earlier called delta-carbon, synthesized at the General Electric Company, has been characterized by Bundy5 as the wurtzite-like polymorph of carbon under the name hexagonal diamond. While the present work was in progress Hanneman et al.6 put forward X-ray evidence for the occurrence of this polymorph in meteorites.

Lonsdaleite, a Hexagonal Polymorph of Diamond

Ca-Al rich phases in the allende meteorite

Antarctic meteorite ALHA81005, discovered in the Allan Hills region of Victoria Land, is a polymict anorthositic breccia which differs from other meteorites in mineralogical and chemical composition but is strikingly similar to lunar highlands soil breccias. The petrologic character and several independent lines of evidence identify ALHA81005 as a meteorite from the moon. Two small clasts of probable mare basalt occur among the highlands lithologies in Thin Section 81005,22. This lunar specimen, which shows relatively minor shock effects, has generated new ideas on the types of planetary samples found on the earth.

The discovery and initial characterization of Allan Hills 81005: The first lunar meteorite

In 1794, Ernst F. F. Chladni published a 63-page book, ber den Ursprung der von Pallas gefundenen und anderer ihr nlicher Eisenmassen und ber einige damit in Verbindung stehende Naturerscheinungen, in which he proposed that meteor-stones and iron masses enter the atmosphere from cosmic space and form fireballs as they plunge to Earth. These ideas violated two strongly held contemporary beliefs: 1) fragments of rock and metal do not fall from the sky, and 2) no small bodies exist in space beyond the Moon. From the beginning, Chladni was severely criticized for basing his hypotheses on historical eyewitness reports of falls, which others regarded as folk tales, and for taking gross liberties with the laws of physics. Ten years later, the study of fallen stones and irons was established as a valid field of investigation. Today, some scholars credit Chladni with founding meteoritics as a science; others regard his contributions as scarcely worthy of mention. Writings by his contemporaries suggest that Chladnis book alone would not have led to changes of prevailing theories; thus, he narrowly escaped the fate of those scientists who propose valid hypotheses prematurely. However, between 1794 and 1798, four falls of stones were witnessed and widely publicized. There followed a series of epoch-making analyses of fallen stones and native irons by the chemist Edward C. Howard and the mineralogist Jacques-Louis de Bournon. They showed that all the stones were much alike in texture and composition but significantly different from the Earths known crustal rocks. Of primary importance was Howards discovery of nickel in the irons and the metal grains of the stones. This linked the two as belonging to the same natural phenomenon. These chemical results, published in February 1802, persuaded some of the leading scientists in England, France, and Germany that bodies do fall from the sky. Within a few months, chemists in France reported similar results and a new field of study was inaugurated internationally, although opposition lingered on until April 1803, when nearly 3,000 stones fell at LAigle in Normandy and transformed the last skeptics into believers. Chladni immediately received full credit for his hypothesis of falls, but decades passed before his linking of falling bodies with fireballs received general acceptance. His hypothesis of their origin in cosmic space met with strong resistance from those who argued that stones formed within the Earths atmosphere or were ejected by lunar volcanoes. After 1860, when both of these hypotheses were abandoned, there followed a century of debate between proponents of an interstellar versus a planetary origin. Not until the 1950s did conclusive evidence of their elliptical orbits establish meteorite parent bodies as members of the solar system. Thus, nearly 200 years passed before the questions of origin that Chladni raised finally were resolved.

https://journals.uair.arizona.edu/index.php/maps/article/download/15495/15483

Ernst Florens Friedrich Chladni (1756–1827) and the origins of modern meteorite research

Continental drift: the evolution of a concept , Continental drift: the evolution of a concept , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Ursula B. Marvin

Papers

Lonsdaleite, a Hexagonal Polymorph of Diamond

Ca-Al rich phases in the allende meteorite

The discovery and initial characterization of Allan Hills 81005: The first lunar meteorite

Ernst Florens Friedrich Chladni (1756–1827) and the origins of modern meteorite research

Continental drift: the evolution of a concept