According to a recent theory, Archean-age gold-quartz vein systems 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 rocks.
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 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 mineralization being modeled, and then tries to select areas for exploration that exhibit as many of the critical features as possible.
Which of the following statements about discoveries of gold deposits is supported by information in the passage?
选了B 对simple prospecting不敏感，没有发现这个是gold rush之前采用的方法，后面没有提及； divide是产生分歧，所以后面也没有分歧； kw也有转变：前面提及的是gold 后面转向了minerals
(第二段提到simple prospecting methods,是说以前gold rush时候用的，后来没有提过，更不用说“divided”之说了，排除)
[这段最末部分的逻辑关系还是很明晰的：exploration --rely on --> ground selection --rely on -->conceptual models --based on --> observation of know deposits + theories of ore-forming
BE中纠结，错选E。 Models based on the theory that gold originated from magmatic fluids have already led to new discoveries of gold deposits.文中未说已经导致了新发现。 http://forum.chasedream.com/thread-337902-1-1.html 丢一个CD的分析贴
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