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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    • "Scattered silica on thin sections was contained about 30-50 %. In deposits of impact structure Silica is freely available (Reimold et al. 2005). Among the samples, was chosen the sample E for the XRF analyzes (Table 1). "
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    ABSTRACT: Despite the extensive records on geomorphological studies in Iran, meteorite impact craters have so far not been considered in to account. Based on both remote sensing technique and field work we have recognized the circular structure of Zirouki crater in the Samsour desert, southeast of Iran, which if confirmed as an impact structure, would be the third impact structure candidate in the Middle East after the Wabar craters in Saudia Arabia and JebelWaqf as Suwwan in Jordan. Geomorphological investigation of the possible impact structure of Zirouki crater was done based on multi criteria methodology including of geological, topographical, geophysical and petrographical studies. Among different studies, topographical investigation indicated that the crater shape morphology was quite obvious with a central uplift projection; as well geophysical pattern provided very strong evidence for possible impact structure, indicating the presence of circular negative gravity anomaly at the whole of the crater.
    Earth Science Informatics 11/2013; 6(4):241-252. DOI:10.1007/s12145-013-0125-3 · 0.69 Impact Factor
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    • "At the Palaeozoic Ames and Newporte impact structures in the North American Williston Basin, epigenetic hydrocarbons are linked to post-impact crater sediments sealed by further sedimentary cover. The Late Triassic $9 km Red Wing Creek impact structure located in the same region acts as a structural trap for progenetic hydrocarbons recovered from intensely faulted and brecciated Palaeozoic sedimentary rocks of the crater basement (Donofrio, 1998; Koeberl et al., 1998; Reimold et al., 2005). Structural repetition of hydrocarbon-rich Early Carboniferous strata in the central uplift, together with impact-induced high porosity and permeability , provide a large oil column ($820 m) and high flow rates (41000 b/d) at Red Wing Creek (Brenan et al., 1975; Grieve, 2005). "
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    ABSTRACT: The Jebel Hadid structure that formed in the Nubian Sandstone of the southern Al Kufrah Basin is a ∼4.7km circular feature with a set of multiple concentric annular ridges. The age of the structure is probably post-Early Cretaceous to pre-Pliocene. As the prevalent geological processes that usually account for the formation of circular structures (magmatism, diapirism, sand volcanism, karst dissolution, glacial erosion) can be widely excluded in this region, we suggest that the Jebel Hadid structure might represent an eroded, complex impact structure. In particular, the Jebel Hadid structure bears a strong morphological resemblance to the impact structure of Tin Bider in Algeria; general host rock properties may be compared to those at the Upheaval Dome impact structure, USA. Numerous terrestrial impact structures are hosts to hydrocarbon reservoirs. This investigation provides a first prospective approach based on remote sensing, discussing the economic potential of a circular structure of suspected impact origin. The still underexplored Al Kufrah Basin is considered as a high potential area for future hydrocarbon exploration. If we consider a possible impact origin of the Jebel Hadid structure, this feature might provide local secondary pathways and traps for hydrocarbon migration/accumulation in the Nubian Series and, thus, ought to be considered as a preferential site for oil and gas exploration.
    Marine and Petroleum Geology 03/2009; 26(3):310-318. DOI:10.1016/j.marpetgeo.2008.04.003 · 2.47 Impact Factor
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    • "Several impact structures contain accumulations of various economic deposits (e.g., Grieve and Masaitis 1994; Reimold et al. 2005). Accordingly (e.g., Carpenter and Carlson 1997; Donofrio 1997; Grieve 1997), many impact structures in the petroleum-bearing basins of the USA and Canada contain commercial hydrocarbon accumulations. "
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    ABSTRACT: Abstract— The Obolon impact structure, 18 km in diameter, is situated at the northeastern slope of the Ukrainian Shield near its margin with the Dnieper-Donets Depression. The crater was formed in crystalline rocks of the Precambrian basement that are overlain by marine Carboniferous and continental Lower Triassic deposits. The post-impact sediments comprise marine Middle Jurassic (Bajocian and Bathonian) and younger Mesozoic and Cenozoic deposits. Today the impact structure is buried beneath an about 300-meter-thick sedimentary rock sequence. Most information on the Obolon structure is derived from two boreholes in the western part of the crater. The lowest part of the section in the deepest borehole is composed by allogenic breccia of crystalline basement rocks overlain by clast-rich impact melt rocks and suevites. Abundant shock metamorphic effects are planar deformation features (PDFs) in quartz and feldspars, kink bands in biotite, etc. Coesite and impact diamonds were found in clast-rich impact melt rocks. Crater-fill deposits are a series of sandstones and breccias with blocks of sedimentary rocks that are covered by a layer of crystalline rock breccia. Crystalline rock breccias, conglomeratic breccias, and sandstones with crystalline rock debris have been found in some boreholes around the Obolon impact structure to a distance of about 50 km from its center. Those deposits are always underlain by Lower Triassic continental red clay and overlain by Middle Jurassic marine clay. The K-Ar age of impact melt glasses is 169 Ma, which corresponds to the Middle Jurassic (Bajocian) age. The composition of crater-fill rocks within the crater and sediments outside the Obolon structure testify to its formation under submarine conditions.
    03/2009; 44(3):389-404. DOI:10.1111/j.1945-5100.2009.tb00740.x
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