Seafloor hydrothermal processes and deposits

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This research aims to solve the mystery of how base and precious metal ore bodies are formed in volcanic rocks. Some of these deposits contain in excess of 100 million tons of ore. These are rare but very desirable because they represent the most cost effective means of producing metals such as zinc, copper, lead, silver and gold that are essential to modern society. Canadian examples such as Kidd Creek in Ontario and Brunswick #12 in New Brunswick would completely fill 10 Toronto Skydomes. Another aspect of my research is to determine the dispersal patterns of contaminants in sediments resulting from the ore-forming process. These contaminants (various metals, barium and arsenic) may provide vectors towards ores. Yet another is to understand the role of micro-organisms in the formation or iron and other base metal ores through the process of "biomineralization". It is generally considered that ore bodies now on land formed in ancient seas where seawater circulating through hot volcanic rocks became heated to 350°C (hot enough to melt lead). This hot sea water leached metals from the rocks and precipitated them as minerals where it discharged onto the sea floor. These metal-rich hot springs, known as "black smokers" because they resemble a dirty industrial process, are found in many regions of the world's oceans but none of them are accumulating metals in anywhere near the amounts of a Kidd Creek. From where, then, did all the metals in Kidd Creek come? The answer may be from fluids and gases, a so-called "magmatic fluid", issuing directly from the molten rock ("magma") that produces lavas from the depths of the Earth. As magmas rise within the seafloor crust, they cool and give off gases, mostly carbon dioxide and water. Some of these gases are trapped as tiny bubbles within the lavas. Careful work on such rocks from the sea bed off eastern Papua New Guinea with high resolution microscopes and micro analytical instruments has shown that accidentally trapped magmatic fluids are extremely rich in metals, many times more that the hot sea water of the black smokers.