笔名探矿者—一个立志执着于探索自然和学术的“打工者”。1962年5月生,福建人,1982年毕业于成都地质学院找矿系,地质调查专业 工学学士 高级工程师。长期从事地质调查、矿产勘查以及矿床学和矿床地球化学研究。在该职业生涯中,积累了三十多年来的地质勘查和找矿经验,脚踏实地一步一个脚印一路走来,具有丰富的工作经验,认识了矿产资源在地壳中的成矿机理,掌握了构造控矿因素与成矿地质规律对找矿预测的意义。本人的专长是既懂理论研究、也精通矿产勘查,善于将两者紧密结合,因而有关成果受到各地政府的关注及业内专家的高度肯定。
Last summer in the Canadian Rockies, we stopped to check out an extraordinary high-contrast exposure of calcite veins in cleaved limestone:
There were your typical (but classic) en echelon lightly-folded tension gashes:
…But there were also these (unique, in my experience) clusters of short, squat veinlets:
We were eager to get out and examine the outcrop…
In his book Canadian Rockies Geology Road Tours, Ben Gadd indicates that this is the Bison Creek Formation, a late Cambrian carbonate unit.
The tension gashes here are due to stresses when the Bison Creek strata were bent into a sharp footwall syncline below the Simpson Pass thrust fault.
The thing that really struck me about this outcrop was the variety of sizes of veins. There were big ones and little ones, relatively planar ones, and folded ones…
Veins (dipping to the right) vs. bedding (subvertical or dipping steeply to the left):
The calcite that fills the veins is likely derived from this same Bison Creek rock, but not 100% of the rock goes into solution when stressed. The organic constituents and the clays aren’t soluble in the same way that the calcite is, so the dark stuff stays behind, and a “pure” calcite is “distilled” from the Bison Creek strata. It’s that constituent which goes on to form the vein-filling stuff.
A contrast in orientations:
A contrast in sizes:
Visually, it doesn’t get much better than this. Awesome place.
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