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Annu Rev Earth Planet Sci 2017 Aug 7;45:389-417. Epub 2017 Jun 7.

Department of Geology, University of Maryland, College Park, Maryland 20742.

The short-lived Hf-W isotope system has a wide range of important applications in cosmochemistry and geochemistry. The siderophile behavior of W, combined with the lithophile nature of Hf, makes the system uniquely useful as a chronometer of planetary accretion and differentiation. Tungsten isotopic data for meteorites show that the parent bodies of some differentiated meteorites accreted within 1 million years after Solar System formation. Read More

Annu Rev Earth Planet Sci 2014 May 3;42:443-467. Epub 2014 Mar 3.

Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida 33199.

Arsenic is the most prevalent environmental toxic element and causes health problems throughout the world. The toxicity, mobility, and fate of arsenic in the environment are largely determined by its speciation, and arsenic speciation changes are driven, at least to some extent, by biological processes. In this article, biotransformation of arsenic is reviewed from the perspective of the formation of Earth and the evolution of life, and the connection between arsenic geochemistry and biology is described. Read More

Annu Rev Earth Planet Sci 2000 ;28:141-67

Lunar and Planetary Lab., University of Arizona, Tucson, 84721, USA.

Natural impacts in which the projectile strikes the target vertically are virtually nonexistent. Nevertheless, our inherent drive to simplify nature often causes us to suppose most impacts are nearly vertical. Recent theoretical, observational, and experimental work is improving this situation, but even with the current wealth of studies on impact cratering, the effect of impact angle on the final crater is not well understood. Read More

Annu Rev Earth Planet Sci 1999 ;27:313-58

Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge 02139, USA.

Stromatolites are attached, lithified sedimentary growth structures, accretionary away from a point or limited surface of initiation. Though the accretion process is commonly regarded to result from the sediment trapping or precipitation-inducing activities of microbial mats, little evidence of this process is preserved in most Precambrian stromatolites. The successful study and interpretation of stromatolites requires a process-based approach, oriented toward deconvolving the replacement textures of ancient stromatolites. Read More

Annu Rev Earth Planet Sci 1997 ;25:403-34

Center for Great Lakes Studies, University of Wisconsin, Milwaukee 53204, USA.

The prokaryotes (bacteria) comprise the bulk of the biomass and chemical activity in sediments. They are well suited to their role as sediment chemists, as they are the right size and have the required metabolic versatility to oxidize the organic carbon in a variety of different ways. The characteristic vertical nutrient (electron donor and electron acceptor) profiles seen in sediments are produced as a result of microbial activities, with each nutrient a product or reactant of one or more metabolic groups. Read More

Annu Rev Earth Planet Sci 1995 ;23:215-49

National Security Council, Washington, DC 20506, USA.

Annu Rev Earth Planet Sci 1990 ;18:317-56

Department of Biochemical and Biophysical Sciences, University of Houston, Texas 77004, USA.