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According to a recent theory, Archean-age gold-quartz veinsystens were formed more than two billion years ago from magmatic fluids that originated from molten granite-like bodies deep beneath the surface of the Earth. This theory is contrary to the widely held view that the systems were deposited from metamorphic fluids, that is, from fluids that formed during the dehydration of wet sedimentary tocks.
The recently developed theory has considerable practical importance. Most of the gold deposits discovered during the original gold rushes were exposed at the Earth’s surface and were found because they had shed trails of alluvial gold that were easily easily traced by simple prospecting methods. Although these same methods still lead to an occasional discovery, most deposits not yet discovered have gone undetected because they are buried and have no surface expression.
The challenge in exploration is therefore to unravel the subsurface geology of an area and pinpoint the position of buried minerals. Methods widely used today include analysis of aerial images that yield a broad geological overview; geophysical techniques that provide data on the magnetic, electrical, and mineralogical properties of the rocks being investigated; and sensitive chemical tests that are able to detect the subtle chemical halos that often envelop mineralization. However, none of these high-technology methods are of any value if the sites to which they are applied have never mineralized, and to maximize the chances of discovery the explorer must therefore pay particular attention to selecting the ground formations most likely to be mineralized. Such ground selection relies to varying degrees on conceptual models, which take into account theoretical studies of relevant factors.
These models are constructed primarily from empirical observations of known mineral deposits and from theories of ore-forming processes. The explorer uses the models to identify those geological features that are critical to the formation of the minerlization being modeled, and then tries to select areas for exploration that exhibit as many of the critical features as possible.
依据最新的理论，太古界时期的金石英脉形成于20亿年前由深入地球表面以下真石胚体熔化形成的岩浆流体。这一理论与广泛认为的由变质岩流体的沉积形成理论(也就是在潮湿泥沙盐的干燥过程中形成)相反。
这一最新形成的理论有重大实践意义。在最初淘金热时发现的金矿床大多显露在地球表面，通过简单的勘探就会发现冲积砂金留下的痕迹，尽管通过这种方法还会偶尔发现金矿，然而大多数没有被发现的金矿就探测不到了，因为这类金矿深埋在地下，在地球表面也没有什么表现。
因此勘探的挑战在于弄清一个地域地表以下的地质问题并为埋藏的矿藏明确定位。今天广泛使用的方法包括：分析航拍图像得出地质概况，运用地球物理技术获得所研究矿石的磁、电和矿物性能，通过敏感的化学实验来检测通常被不易察觉的化学晕所包围的矿化。但是，如果勘察的这些地点从来没有矿化，想要有所发现勘探者就要特别留意挑选最有矿化可能的底层。这样在这些高科技方法中，就没有一个有任何价值了。这种地层选择依赖于概念模型的程度变化，而概念模型要考虑相关因素的理论研究。
这些模型的建立，主要是依据对所知矿石的实验观察和成矿过程的理论。勘探者用这些模型来鉴别所模拟矿化形成的临界地质特征，然后试着挑选具有较多临界特征的勘探地域。
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