During Leg 168 of the Ocean Drilling Program, basalts were recovered by drilling and subsurface water was collected with a water sampling tool at Hole 1026B on the east flank of Juan de Fuca Ridge. Microorganisms were found in both types of samples. The microorganisms in the basalt appear to...
Within the altered parts of the glass rim of pillow lavas of Hole 896A, at depths at least 432 m below seafloor (237 m below the top of volcanic basement), microbes have been identified. This is indicated by the size and shapes of alteration textures and verified by the presence...
The safety of coastal infrastructure has been a concern after the Indian Ocean Tsunami in 2004 and the Great East Japan Tsunami in 2011. The western coast of the United States is also exposed to tsunami hazards due to the Cascadia subduction zone. Therefore, it is critical to design coastal...
Microchannels in ocean basalt glass are often attributed to the activity of microorganisms, however, neither the mechanism of formation of microchannels in glass nor the involvement of microorganisms have been confirmed by experimentation. Experimental abiotic corrosion of basalt glass with 1% hydrofluoric acid (HF), a proxy for more slowly acting...
Hydrothermal vents appear to be the tip of the subsurface biosphere in the ocean crust. The primary prducers in this biosphere are prokaryotes that tolerate a wide variety of physical and chemical conditions and are versatile in their use of inorganic compounds to drive metabolism. A synthesis of chemical and...
Oceanic crust covers nearly 70% of the Earth's surface, of which, the upper,
sediment layer is estimated to harbor substantial microbial biomass. Marine crust;
however, extends several kilometers beyond this surficial layer, and includes the
basalt and gabbro layers. In particular, the basalt layer has high permeabilities which
allows for...
In the early 1980's the first evidence of biological alteration of basalt glass (sideromelane) was published. Since that time additional evidence, including DNA staining, isotopic abundance and chemical mapping, has come to light suggesting that this unique alteration of glass can be attributed to microbial activity. Microbial alteration textures have...
These first measurements of specific surface area (SSA)
of bulk samples of subsurface marine basalts were undertaken
to determine the potential area available for microbial
colonization. SSA ranged from 0.3 to 52 m2/g of basalt
with the lowest value coming from pillow basalt and the
highest value from breccia. The...
The subsurface microbial biosphere in the igneous oceanic crust has implications for global geochemical cycling, early life on Earth, and the search for life on Mars. Microscopic evidence of a subsurface microbial ecosystem includes biotic alteration textures associated with basaltic glass. The exact conditions in the basaltic layer that make...
The Hawaii Scientific Drilling Program (HSDP) cored and recovered igneous rock from the surface to a
depth of 3109 m near Hilo, Hawaii. Much of the deeper parts of the hole is composed of hyaloclastite
(fractured basalt glass that has been cemented in situ with secondary minerals). Some hyaloclastite units...