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PREVIEW ALL MODIFIED FROM ORIGINAL PAPER : View

1. Pockmarks

2. Mud Volcanoes

3. Deep-Water Coral Reefs

4. Gas Hydrates

5. New Salt Theory

6. Articles and books by MH

7. Submarine biology

8. My boats

9. Mars and Hydrothermal Salt

10. Seabed Carbono-Fertilization, SeCaF

11. Links

The Hydrothermal Mud Theory

General the thick of mud layers

Kilometre thick layers of mud (clay) covers the world’s oceanic crust and portions of continental crust. Where does all this clay originate?

Rivers and glaciers is a common answer. However, there may be another, much more active and virulent culprit – the deep-ocean hot vents and buried hydrothermal systems.

The role of sea water

What happens when seawater enters down into the porous and fractured oceanic crust?

It heats up and becomes supercritical because of the high pressure (i.e., more than 300 bar pressure).

When water is in its supercritical state, it has a density of only 0.3 g/cm3 and flows into any crack or fissure, no matter how thin it may be.

Actually, supercritical water produces its own voids, as it flows effortlessly through rock by dissolution – like smoke drifting through air!

Supercritical water is so acid and reactive that it dissolves any rock type. In its wake, it leaves behind ‘alteration products’ and re-mineralized rock.

It leaves beautiful patterns, ranging from highly fractured and veined rock, to whispy patterns, like turbulent flowing water.

Mineral colloids

One of its products is mineral colloids, which are transported in a slurry through rock conduits, the hydrothermal zones of rock and sedimentary layers.

The colloids react with each other and form various kinds of clay minerals (montmorillonite, kaolinite, etc.) according to mineral types being transported.

Mud Volcano

Mud volcanoes are one of the surface manifestations of this type of hydrothermal system.

LUSI, THE NEW MUD VOLCANO

LUSI, the new mud volcano erupting on SE Java, is just another manifestation of the activity of supercritical water at depth.

This vent, that unfortunately erupted in a rural area (where mud volcanoes have erupted before), taps into a more-or-less endless (bottomless) reservoir of such hydrothermal alteration products.

These liquid muds are produced up to 12 kilometres under ground where high-heatflow conditions occur, due to the proximity to normal volcanoes. T

he grand-scale subduction process, which is continually active underneath Java, ensures an unending supply of seawater and sedimentary rocks, which become dissolved by supercritical water.

MUD VOLCANO

The suspected interior anatomy (plumbing system) of the Dashgil mud volcano, Azerbaijan. Image by M. Hovland.

Garadag mud volcano, about 40 km south of Baku, Azerbaijan, is a classical mud volcano. Håkon Rueslåtten for scale to the right. Year 2002.

Overlooking the mud volcanic crater at Garadag. Notice the oil drilling rig in the background. The Caspian Sea is at the very far background.

Detail from a vent on a Dashgil gryphon (chimney)

A detail on the Garadag volcanic crater. It is evident that although the surface of the mud is constantly moving, the seep-location is stationary. In a mud volcano crater there are always numerous seep locations like this one.

A conceptual diagram showing how we think that mud volcanoes are linked to deeply buried hydrothermal ‘motors’, where supercritical water is constantly forming.

Another conceptual diagram showing how we envision the temperature gradient and the pressure gradient may vary with depth, beneath mud volcanoes. Abbreviations: SCRIW= supercritical water, RB= retrograde boiling, LH= Latent heat, IR= Intermediate reservoir.

See also Hovland et al. (2006), Journal of Geochemical Exploration

More Mud Volcanoes

Mud volcanoes occur on various parts of the earth’s surface.

Although they occur in abundance in places like Azerbaijan, Makran (Pakistan), and on Trinidad, most of them occur on the seabed.