Organic Compounds in Meteorites and Their Origins 

The Chemistry of Interstellar Molecules

Chemistry in Comets

Marine Manganese Nodules

THE fascinating problem of the origin of liquid petroleum, with which we must associate natural gas, mineral waxes, and asphaltic materials, is primarily of interest to geologists and chemists, but its solution would have a wider impact, since it would throw some light on certain aspects of the early history of the earth and the first steps in the evolution of living forms. 

Ore deposits are distributed unevenly on Earth and tend to cluster in specific large-scale zones for which de Launay (1913) introduced the term "metallogenic province". The observational background for this situation has been known since the earliest days of mining. Pliny the Elder (A.D. 23-79) states with reference to silver-bearing veins: "...ubicumque una inventa vena est, non procul invenitur alia". (Where a vein is found, there will be another one not far away). 

1    Corresponding Main Metallogenic Epochs to Key Geological Events in the North China Craton: An Example for Secular Changes in the Evolving Earth    
Mingguo Zhai and Xiyan Zhu
Part I Archean Crustal Growth and Metallogeny
2    Archean Continental Crust in the Southern North China Craton 

Chunrong Diwu, Chengli Zhang, and Yong Sun
3    Structural Architecture and Spatial-Temporal Distribution of the Archean Domains in the Eastern North China Craton    
Peng Peng

This paper is an overview of the diverse types of uranium deposits that are recognized in the world, exclusive of Europe, and presents brief descriptions of selected deposits of each major type. Descriptions of geology, mineralogy, genesis and economics of each type of deposit precede summaries of selected occurrences of most types. The locations of described deposits are shown in Fig. 1.  <...>

The shock metamorphic effects observed in meteorites can be described in terms of either deformation or transformation or some combination of the two. As mentioned in Chap. 3, the deformation effects include fracturing, plastic deformation, twinning, and mosaicism within constituent minerals. Planar deformation features (PDFs) have been attributed to deformational processes, but they have also been shown to contain transformed material, either diaplectic glass or high-pressure phases (Xie and Chao 1987; Goltrant et al. 1991; Bowden 2002).

The platinum-group element (PGE) potential of four chromite mining districts in southern and south-eastern Iran was investigated using geochemical and mineralogical methods. A total of 20 mines and prospects were sampled in the Neyriz ophiolite, the Abdasht and Sikhuran complexes in the Esfandagheh district, and the Faryab district. Chromitite and dunite were analysed for major, trace element and PGE geochemistry, and the platinumgroup element mineralogy (PGM). In all mining districts, chromites analysed from mantle tectonite, probable transition zone and cumulate zone chromitites are refractory, low in TiO2 (b0.3 wt.%) as well as Cr- and Mgrich, with Cr# [100*Cr /(Cr+Al)] ranging from 70 to 81 and Mg# [100*Mg /(Mg+ Fe2+)] ranging from 40 to 83.