Archean microfossils provide some of the earliest physical evidence for life on Earth, yet there remains a great deal of uncertainty regarding which micro-organisms were actually preserved. Because of the limited cellular detail remaining, interpretation of those microfossils has been based solely on size and morphology. This has led to significant controversy surrounding the presence or absenc...

Experiments on microorganisms capable of surviving silicification are often conducted to gain a better understanding of the process of silica biomineralization and to gain insights into microbially influenced rock formations and biofabrics like those found in ancient deposits such as the Early Archean Apex Chert formation (Schopf, 1993; House et al., 2000). An ideal microorganism for studying s...

Recently discovered synthesis of unusual curved nanoporous silica shapes, such as rods, discoids, spheres, tubes, and hollow helicoids, have brought forth the problem of understanding the formation mechanism. Knowledge of such mechanism may lead to the ability to control the nanoporous shapes. This is important in a variety of applications and new technologies where nanostructure and geometry d...

Silicification is a diagenetic process commonly observed in sedimentary sections of the Aptian carbonate deposits Santos Basin that involves replacement minerals with silica. It mostly associated hydrothermal fluids percolating through faults and fractures. CO2 degassing favors an increase acidity. Consequently, became subsaturated calcite supersaturated Given silica content, two distinct behav...