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石灰岩与白云岩的鉴别,对野外地质工作者来说是一个难题。过去,所提鉴别方法虽多,但都较繁琐。我们这里提出的基本上是用肉眼鉴别的方法,掌握此方法后,将有助于石灰岩及白云岩的鉴别,且十分有助于对赋存于其中的矿床的找矿与勘探。我们利用此法在滇东北、滇中、滇西等地应用,均获良好效果。通过野外简场识别石灰岩与白云岩,又为我们提供了矿床新的成矿规律的认识。现仅以滇东北产于碳酸盐岩石中的铅锌矿床为例可以看出铅锌矿产于特定的沉积岩相中,即①产于白云岩中,不产于石灰岩等含MgO低的岩石中;②产于海相化学沉积和交代的白云岩中,不产于碎屑沉积的白云岩中;③产于化学沉积和交代白云岩相沉积韵律的上部或顶部,不产于其中、下部。
Identification of limestone and dolomite, is a problem for field geologists. In the past, the methods of identification were many, but they were more cumbersome. What we present here is basically a method of identification with the naked eye. After mastering this method, it will be helpful for the identification of limestone and dolomite, and is very helpful for the prospecting and prospecting of the deposit hosted therein. We use this method in northeast Yunnan, Yunnan, western Yunnan and other places, have achieved good results. The identification of limestone and dolomite by the field briefing also provided us with a new understanding of the ore-forming laws. Taking the lead-zinc deposits produced in carbonate rocks in Northeast Yunnan as an example, we can see that lead-zinc deposits are produced in specific sedimentary facies, that is, ① are produced in dolomite and are not produced in rocks with low MgO such as limestone ; ② produced in the marine sedimentary and chemical dolomite accretion, is not produced in clastic sedimentary dolomite; ③ produced in chemical deposition and deposition dolomite sedimentary rhythm of the upper or top, not produced in the lower part.