Airborne magnetic and radiometric survey, central Arkansas and southern Missouri, 2023

This publication provides digital flight line data for a high-resolution magnetic and radiometric survey over part of central Arkansas and southern Missouri. The airborne geophysical survey was funded by the Earth Mapping Resources Initiative and was designed to meet the complimentary needs related to geologic mapping and mineral resource research.  The survey covers an irregularly shaped area of approximately 75,070 square kilometers (km2) from southern Missouri, across part of the Arkoma basin and Ouachita Mountains into central Arkansas and includes 282,029 line-km of magnetic and radiometric data. Data were collected from fixed-wing aircraft flown at a median terrain clearance of 115 meters (m) above topography along north-south flight lines spaced at 300-m intervals. Tie lines were flown in an east-west direction every 3,000 m. Data were collected by EON Geosciences Inc. under contract with the USGS using five fixed-wing aircraft with a magnetometer mounted in the tail stinger and a fully calibrated gamma-ray spectrometer. The survey operated out of the Branson Airport in Missouri, the West Memphis Municipal Airport in Tennessee, and the North Little Rock Municipal and Texarkana Regional Airports in Arkansas from November of 2022 to May of 2023. Files that are available in this publication include flight line data for the magnetic survey, flight line data for the radiometric survey and a report describing the survey parameters, field operations, quality control and data reduction procedures. A zip file is provided that contains the contractor's deliverable products that includes Geosoft databases and grids for this magnetic and radiometric survey and the report describing the survey and data reduction. These products can be accessed using the free software Geosoft Viewer or the commercial Oasis montaj software.

本公开数据集提供了阿肯色州中部与密苏里州南部部分区域的高分辨率磁法与放射测量航空飞行线数据。本次航空地球物理调查（airborne geophysical survey）由地球测绘资源倡议（Earth Mapping Resources Initiative）资助，旨在满足地质填图与矿产资源研究相关的互补性需求。本次调查区域呈不规则形状，面积约75070平方千米，覆盖范围从密苏里州南部出发，穿过阿科马盆地（Arkoma basin）与沃希托山脉（Ouachita Mountains），延伸至阿肯色州中部，共包含282029测线千米的磁法与放射测量数据。数据由固定翼飞机采集，飞行时距地形的平均离地高度为115米，沿南北向布设测线，线间距为300米；每3000米布设一条东西向联络测线（tie lines）。本次数据采集工作由EON地球科学公司（EON Geosciences Inc.）受美国地质调查局（USGS）委托开展，共使用五架固定翼飞机，机尾尾杆搭载了磁力仪，且搭载了经过完全校准的伽马射线能谱仪（gamma-ray spectrometer）。本次调查的作业基地包括密苏里州布兰森机场（Branson Airport）、田纳西州西孟菲斯市政机场（West Memphis Municipal Airport），以及阿肯色州北小岩城市政机场与特克萨卡纳区域机场，作业时段为2022年11月至2023年5月。本公开数据集提供的可用文件包括磁法测量飞行线数据、放射测量飞行线数据，以及一份详述调查参数、野外作业流程、质量控制方案与数据归约（data reduction）流程的报告。此外还提供了一个压缩包，内含承包商交付的成果产品，包括本次磁法与放射测量的Geosoft数据库（Geosoft databases）与网格数据，以及详述调查与数据归约流程的报告。上述成果可通过免费软件Geosoft Viewer或商业软件Oasis montaj进行访问。