Pond Creek Coal zone Point Data (Chemistry) in Virginia and West Virginia

This dataset (located by latitude and longitude) is a subset of the
geochemical dataset found in Chap. H, Appendix 2, Disc 1, and used
in this study of the Pocahontas No. 3 coal bed. That dataset is a
compilation of data from the U.S. Geological Survey's (USGS) National
Coal Resources Data System (NCRDS) USCHEM (U.S. geoCHEMical), The
Pennsylvania State University (PSU), and the West Virginia Economic and
Geological Survey (WVGES) coal quality databases. The metadata file for
the complete dataset is found in Chap. H, Appendix 3, Disc 1
(please see it for more detailed information on this geochemical
dataset). This subset of the geochemical data for the Pocahontas No.
3 coal bed includes ash yield, sulfur content, SO2 value, gross
calorific value, arsenic content and mercury content for these
records, as well as the ranking of these values, which is described
later under the attributes in this metadata file. Analytical techniques
are described in the references in Chap. H, Appendix 4, Disc 1. The
analytical data are stored as text fields because many of the parameters
contain letter qualifiers appearing after the numerical data values. The
following is a list of the possible qualifier values: L - less than, G -
greater than, N - not detected, or H - interference that cannot be
easily resolved. Not all of these codes may be in this database.

本数据集（经纬度定位）为第H章附录2光盘1所载地球化学数据集的子集，用于本次波卡洪塔斯3号煤层（Pocahontas No. 3 coal bed）相关研究。该原始数据集整合了来自美国地质调查局（U.S. Geological Survey, USGS）国家煤炭资源数据系统（National Coal Resources Data System, NCRDS）USCHEM（美国地球化学数据集，U.S. geoCHEMical）、宾夕法尼亚州立大学（Pennsylvania State University, PSU）以及西弗吉尼亚州经济与地质调查局（West Virginia Economic and Geological Survey, WVGES）煤炭质量数据库的多源数据。完整数据集的元数据文件收录于第H章附录3光盘1，如需了解该地球化学数据集的详细信息，请查阅该文件。本次针对波卡洪塔斯3号煤层的地球化学数据子集，包含各记录的灰分产率、硫含量、SO₂值、总热值、砷含量与汞含量，以及各参数的数值等级划分，相关说明将在本元数据文件的属性章节中详述。分析方法详见第H章附录4光盘1所列参考文献。由于多数参数的数值后附带字母限定符，分析数据以文本字段形式存储。以下为可用的限定符取值列表：L代表小于（less than）、G代表大于（greater than）、N代表未检出（not detected），H代表存在难以轻易解决的干扰。本数据库未必涵盖所有上述编码。