Geochemical analyses of rock samples collected from mineral deposits and intrusions of the Bokan Mountain peralkaline granitic complex, Prince of Wales Island, southeastern Alaska

This data set compiles the major and trace element chemistry of rock samples collected by the U.S. Geological Survey (USGS) at Bokan Mountain, located in the southern part of Prince of Wales Island, southeastern Alaska. Bokan Mountain was formed by an Early Jurassic peralkaline igneous complex that intruded into lower Paleozoic rocks of the Alexander terrane of southeast Alaska. The pluton and surrounding country rocks host numerous mineral deposits and occurrences, including heavy rare earth element (HREE)-rich pegmatites and felsic dikes, as well as mineral deposits rich in uranium, thorium, HREE, and fluorine. The Ross-Adams mine on Bokan Mountain exploited a uranium-thorium deposit intermittently from the late 1950s to 1971, and remains the only uranium producer in Alaska. Recent exploration by Ucore Rare Metals Inc. (http://ucore.com/) at Bokan Mountain has focused on the Dotson and I and L Zones, which together form a 2.5-km-long, 50 m-wide zone of thin felsic dikes and pegmatites (each rarely more than 2-m-wide) that are enriched in rare earth elements (REE). Ucore Rare Metals has reported an inferred resource for the combined zones as 5.275 million metric tons of ore at 0.654 percent total REE oxides, using a cutoff of 0.4 percent total REE oxides; about 40 percent of the total REE oxides in these dikes and pegmatites are the HREE (http://ucore.com/Ucore_43-101.pdf). This data release provides the analytical results of 153 rock hand samples collected by USGS geologists during site visits to Bokan Mountain in 2010, 2011, and field studies during 2014. The samples represent a variety of rock types associated with the Bokan Mountain igneous complex, including mineral deposits, prospects and occurrences, along with examples of unaltered intrusions of the pluton. The samples were analyzed for 55 major and trace elements using inductively coupled plasma-atomic emission spectrometry (ICP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS) and also analyzed for major elements using wavelength dispersive x-ray fluorescence spectrometry (WDXRF). This data set is provided for future use in geologic, exploration, and environmental background studies of Bokan Mountain and its mineral deposits.

本数据集汇编了美国地质调查局（U.S. Geological Survey, USGS）在阿拉斯加东南部威尔士亲王岛南部博坎山采集的岩石样品的主量与微量元素化学数据。
博坎山由早侏罗世过碱性火成杂岩体构成，该岩体侵入于阿拉斯加东南部亚历山大地体的下古生界岩石中。
该深成岩体及周边围岩产出众多矿床与矿化点，包括富重稀土元素（heavy rare earth element, HREE）的伟晶岩与长英质岩脉，以及富含铀、钍、重稀土元素与氟的矿床。
博坎山的罗斯-亚当斯矿自20世纪50年代末至1971年断续开采铀-钍矿床，至今仍是阿拉斯加唯一的铀矿生产基地。
优科稀土金属公司（Ucore Rare Metals Inc.，http://ucore.com/）近期在博坎山的勘探工作聚焦于Dotson矿区与I and L矿区，二者共同构成一条长2.5千米、宽50米的薄长英质岩脉与伟晶岩带（单条岩脉或伟晶岩宽度罕有超过2米），该带稀土元素（rare earth elements, REE）富集。优科稀土金属公司报告称，以总稀土氧化物0.4%为边界品位，上述合并矿区的推断资源量为527.5万吨矿石，总稀土氧化物品位为0.654%；该类岩脉与伟晶岩中约40%的总稀土氧化物为重稀土元素（http://ucore.com/Ucore_43-101.pdf）。
本数据发布内容包含美国地质调查局地质学家于2010年、2011年实地考察及2014年野外研究期间采集的153件手标本岩石的分析结果。
这些样品涵盖了与博坎山火成杂岩体相关的各类岩石类型，包括矿床、矿点与矿化点，同时包含该深成岩体未蚀变侵入体的典型样品。
本次分析采用电感耦合等离子体原子发射光谱法（inductively coupled plasma-atomic emission spectrometry, ICP-AES）与电感耦合等离子体质谱法（inductively coupled plasma-mass spectrometry, ICP-MS）测定了55项主量与微量元素含量，并采用波长色散X射线荧光光谱法（wavelength dispersive x-ray fluorescence spectrometry, WDXRF）分析主量元素成分。
本数据集旨在为博坎山及其矿床的地质、勘探与环境背景研究提供可供未来使用的数据支撑。