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通过野外和室内的仔细研究,在枫林矿区及其外围下石炭统梓山组及中上石炭统壶天群下部,发现有广泛的火山岩,包括英安斑岩、流纹岩,及酸性到中性的凝灰岩,凝灰角砾岩及火山碎屑沉积岩等,总厚度20余米。与这些主要海底火山岩层及其他海相沉积物互层的为层状黄铁矿型铜矿层,它主要是由黄铁矿,胶黄铁矿,菱铁矿,黄铜矿,辉铜矿及少量闪锌矿等组成,其总厚度约28米,构成中型的铜矿山。在黄铁矿型铜矿层之上,有厚达13米的硅质赤铁矿层及20—30米厚的硅质岩层,再往上完全复盖以壶天群灰岩。大部分硅质赤铁矿层都是含钨的,并构成低品位的钨矿床,其厚度为8米,钨主要呈离子状态被吸附在赤铁矿层中,只有在受到花岗斑岩影响的地段,经过后期热液作用,才偶尔见到钨铁矿、钨锰矿及白钨矿的细小晶体。总之,由于这些黄铁矿型铜矿床及含钨赤铁矿层与海底火山岩及海相沉积物具有的密切联系,所以它们被认为是由海底火山沉积作用形成的。并在燕山期又受到微弱的热液迭加及改造作用。
Through careful study both in the field and in the interior, a wide range of volcanic rocks, including amphibolite, rhyolite and acid to medium, have been found in the lower part of the Lower Carboniferous Zhushan Formation and the Lower Carboniferous in the Fenglin Mining Area and its periphery Tuff, tuffaceous breccia and pyroclastic sedimentary rocks, with a total thickness of more than 20 meters. Layered pyrite-type copper deposits interbedded with these major submarine volcanic rocks and other marine sediments are mainly composed of pyrite, phlogoid pyrite, siderite, chalcopyrite, chalcocides And a small amount of sphalerite and other components, the total thickness of about 28 meters, constitute a medium-sized copper mines. Above the pyrite-type copper deposit, there are siliceous hematite deposits of up to 13 m in thickness and siliceous formations of 20-30 m thick, which are then fully covered with pot-day limestone. Most of the siliceous hematite layers are tungsten-containing and form low-grade tungsten deposits with a thickness of 8 m. The tungsten is mainly ionized and is adsorbed in the hematite layer. Only in the presence of granite porphyry Of the area, after the late hydrothermal effect, and occasionally to see the tungsten ore, wolframite and scheelite small crystals. In summary, these pyrite-type copper deposits and tungsten-bearing hematite beds are thought to have been formed by submarine volcanic sedimentation because of their close association with seabed volcanics and marine sediments. And in the Yanshan period has been weak hydrothermal superposition and transformation.