Chapter

Economic Mineral Deposits in Impact Structures: A Review

DOI: 10.1007/3-540-27548-7_20

ABSTRACT Many large meteorite impact structures throughout the world host mineral resources that are either currently mined or have
the potential to become important economic resources in the future. The giant Vredefort-Witwatersrand and Sudbury impact structures
underline this statement, because of their enormous resources in gold and uranium, and nickel, copper, and PGEs, respectively.
In relation to impact, three basic types of ore deposits in impact structure settings have been distinguished: (1) progenetic (i.e., pre-impact) deposits that already existed in the target regions prior to an impact event, but may have become accessible
as a direct result of the impact; (2) syngenetic (syn-impact) deposits that owe their existence directly to the impact process, and (3) epigenetic (immediately post-impact) deposits that result from impact-induced thermal/hydrothermal activity. In addition to metalliferous
ore deposits related to impact structures, impact structure-hosted epigenetic hydrocarbon deposits are reviewed and are shown
to make a major contribution to the North American economies. Non-metallic resources, such as minerals derived from crater-lake
deposits, dimension stone, and hydrological benefits, may also be derived from impact structures, and the educational and
recreational value of many meteorite impact craters can be substantial.

Undoubtedly, impact structures - at least those in excess of 5–10 km diameter - represent potential exploration targets for
ore resources of economic magnitude. This important conclusion must be communicated to exploration geologists and geophysicists.
On the other hand, impact workers ought to be familiar with already established fact concerning ore deposits in impact environments
and must strive towards further understanding of the ore generating processes and styles of emplacement in impact structures.

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