Drew L J, Schuenemeyer J H, Armstrong T R, Sutphin D M
U.S. Geological Survey, Reston, VA 20192, USA.
Ground Water. 2001 Sep-Oct;39(5):676-84. doi: 10.1111/j.1745-6584.2001.tb02357.x.
A model is proposed to explain the statistical relations between the mean initial water well yields from eight time increments from 1984 to 1998 for wells drilled into the crystalline bedrock aquifer system in the Pinardville area of southern New Hampshire and the type of bedrock, mean well depth, and mean well elevation. Statistical analyses show that the mean total yield of drilling increments is positively correlated with mean total well depth and mean well elevation. In addition, the mean total well yield varies with rock type from a minimum of 46.9 L/min (12.4 gpm) in the Damon Pond granite to a maximum of 74.5 L/min (19.7 gpm) in the Permian pegmatite and granite unit. Across the eight drilling increments that comprise 211 wells each, the percentages of very low-yield wells (1.9 L/min [0.5 gpm] or less) and high-yield wells (151.4 L/min [40 gpm] or more) increased, and those of intermediate-yield wells decreased. As housing development progressed during the 1984 to 1998 interval, the mean depth of the wells and their elevations increased, and the mix of percentages of the bedrock types drilled changed markedly. The proposed model uses a feed-forward mechanism to explain the interaction between the increasing mean elevation, mean well depth, and percentages of very low-yielding wells and the mean well yield. The increasing percentages of very low-yielding wells through time and the economics of the housing market may control the system that forces the mean well depths, percentages of high-yield wells, and mean well yields to increase. The reason for the increasing percentages of very low-yield wells is uncertain, but the explanation is believed to involve the complex structural geology and tectonic history of the Pinardville quadrangle.
本文提出了一个模型，用于解释新罕布什尔州南部皮纳德维尔地区钻入结晶基岩含水层系统的水井，在1984年至1998年八个时间增量下的平均初始水井产量与基岩类型、平均井深和平均井高程之间的统计关系。统计分析表明，钻井增量的平均总产量与平均总井深和平均井高程呈正相关。此外，平均总井产量随岩石类型而变化，从达蒙池塘花岗岩中的最小值46.9升/分钟（12.4加仑/分钟）到二叠纪伟晶岩和花岗岩单元中的最大值74.5升/分钟（19.7加仑/分钟）。在由211口水井组成的八个钻井增量中，极低产量水井（1.9升/分钟[0.5加仑/分钟]或更低）和高产量水井（151.4升/分钟[40加仑/分钟]或更高）的百分比增加，中等产量水井的百分比下降。在1984年至1998年期间，随着住房开发的推进，水井的平均深度及其高程增加，所钻基岩类型的百分比组合也发生了显著变化。所提出的模型使用前馈机制来解释平均高程增加、平均井深以及极低产量水井百分比与平均井产量之间的相互作用。随着时间推移，极低产量水井百分比的增加以及房地产市场的经济因素可能控制着迫使平均井深、高产量水井百分比和平均井产量增加的系统。极低产量水井百分比增加的原因尚不确定，但据信其解释涉及皮纳德维尔四边形复杂的构造地质和构造历史。
