Geologic and magnetic survey of a part of the Palmer 7 12-minute quadrangle, Michigan

In the last decades, geophysical methods such as magnetic survey have become a common technique for prospecting archaeological sites. At sub-Saharan archaeological sites, however, magnetic survey and correlated techniques never came into broad use and there are no signs for an immediate change of this situation. This paper examines the magnetic survey undertaken on the Nigerian site of Zilum, a settlement of the Gajiganna Culture (ca 1800-400 BC) located in the Chad Basin and dated to ca 600-400 BC. By means of the present case study, we demonstrate the significance of this particular type of investigation in yielding complementary data for understanding the character of prehistoric settlements. In conclusion, we point out that geophysical methods should play a more important role in modern archaeological field research, as they furnish a class of documentation not achievable by traditional survey and excavation methods, thus creating new perspectives for interpreting the past of African societies.

Airborne geophysical surveys in Greenland in 1998

Geological Survey of Denmark and Greenland Bulletin ◽

10.34194/ggub.v183.5202 ◽

1999 ◽

pp. 34-38 ◽

Cited By ~ 2

Author(s):

Thorkild M. Rasmussen ◽

Leif Thorning

Keyword(s):

High Resolution ◽

Geophysical Data ◽

Digital Data ◽

Geological Survey ◽

Magnetic Data ◽

Magnetic Survey ◽

Original Series ◽

Geophysical Surveys ◽

The Government

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Rasmussen, T. M., & Thorning, L. (1999). Airborne geophysical surveys in Greenland in 1998. Geology of Greenland Survey Bulletin, 183, 34-38. https://doi.org/10.34194/ggub.v183.5202 _______________ Airborne geophysical surveying in Greenland during 1998 consisted of a magnetic project referred to as ‘Aeromag 1998’ and a combined electromagnetic and magnetic project referred to as ‘AEM Greenland 1998’. The Government of Greenland financed both with administration managed by the Geological Survey of Denmark and Greenland (GEUS). With the completion of the two projects, approximately 305 000 line km of regional high-resolution magnetic data and approximately 75 000 line km of detailed multiparameter data (electromagnetic, magnetic and partly radiometric) are now available from government financed projects. Figure 1 shows the location of the surveyed areas with highresolution geophysical data together with the area selected for a magnetic survey in 1999. Completion of the two projects was marked by the release of data on 1 March, 1999. The data are included in the geoscientific databases at the Survey for public use; digital data and maps may be purchased from the Survey.

Airborne geophysical surveys in Greenland – 1996 update

Geological Survey of Denmark and Greenland Bulletin ◽

10.34194/ggub.v176.5069 ◽

1997 ◽

pp. 75-79

Author(s):

Robert W. Stemp

Keyword(s):

Mineral Exploration ◽

Geological Mapping ◽

Digital Data ◽

Magnetic Survey ◽

Aeromagnetic Survey ◽

West Greenland ◽

South West ◽

Geophysical Surveys ◽

The Government ◽

Airborne Geophysical Data

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Stemp, R. W. (1997). Airborne geophysical surveys in Greenland – 1996 update. Geology of Greenland Survey Bulletin, 176, 75-79. https://doi.org/10.34194/ggub.v176.5069 _______________ Two major airborne geophysical surveys were carried out in 1996, the third year of a planned five-year electromagnetic and magnetic survey programme (project AEM Greenland 1994–1998) financed by the Government of Greenland, and the second year of an aeromagnetic survey programme (project Aeromag) jointly financed by the governments of Denmark and Greenland; both projects are managed by the Geological Survey of Denmark and Greenland (GEUS). The two 1996 surveys were: 1) Project Aeromag 1996 in South-West and southern West Greenland;2) Project AEM Greenland 1996 in South-West Greenland. All areas surveyed and planned for future surveys as of March 1997 are shown in Figure 1. Results of both the 1996 surveys were released in March 1997, as a continuation of a major effort to make high quality airborne geophysical data available for both mineral exploration and geological mapping purposes. The data acquired are included in geoscientific databases at GEUS for public use; digital data and maps may be purchased from the Survey. The main results from the 1996 surveys are described in Thorning & Stemp (1997) and Stemp (1997). Two further new airborne surveys have already been approved for data acquisition during the 1997 field season, with subsequent data release in March 1998. A summary of all surveys completed, in progress or planned since the formal inception of project AEM Greenland 1994–1998 is given in Table 1. The programme was expanded to include a separate regional aeromagnetic survey in 1995, provisionally for 1995–1996, with extension subject to annual confirmation and funding.

Ritual Economy and the Organization of Scioto Hopewell Craft Production: Insights from the Outskirts of the Mound City Group

American Antiquity ◽

10.1017/aaq.2019.105 ◽

2020 ◽

Vol 85 (2) ◽

pp. 279-304

Author(s):

Timothy D. Everhart ◽

Bret J. Ruby

Keyword(s):

Craft Production ◽

Small Scale ◽

Magnetic Survey ◽

Middle Woodland ◽

The North ◽

Large Structures ◽

Production Site ◽

Production And Consumption ◽

Ritual Economy ◽

City Group

This article offers insights into the organization of Scioto Hopewell craft production and examines the implications of this organization through the lens of ritual economy. We present a novel analysis of investigations at the North 40 site, concluding that it is a craft production site located on the outskirts of the renowned Mound City Group. High-resolution landscape-scale magnetic survey revealed a cluster of three large structures and two rows of associated pits; one of the buildings and three of the pits were sampled in excavations. Evidence from the North 40 site marks this as the best-documented Scioto Hopewell craft production site. Mica, chert, and copper were crafted here in contexts organized outside the realm of domestic household production and consumption. Other material remains from the site suggest that crafting was specialized and embedded in ceremonial contexts. This analysis of the complex organization of Scioto Hopewell craft production provides grounds for further understanding the elaborate ceremonialism practiced by Middle Woodland (AD 1–400) societies and adds to the known complexity of craft production in small-scale societies. Furthermore, this article contributes to a growing body of literature demonstrating the utility of ritual economy as a framework for approaching the sociality of small-scale societies.

Compact Quantum Magnetometer System on an Agile Underwater Glider

Sensors ◽

10.3390/s21041092 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1092

Author(s):

Brian R. Page ◽

Reeve Lambert ◽

Nina Mahmoudian ◽

David H. Newby ◽

Elizabeth L. Foley ◽

...

Keyword(s):

Test Procedure ◽

Reduction Process ◽

Ground Truth ◽

Sensor Technology ◽

Magnetic Data ◽

Magnetic Survey ◽

Underwater Glider ◽

Combined System ◽

Extended Operation ◽

Quantum Magnetometer

This paper presents results from the integration of a compact quantum magnetometer system and an agile underwater glider for magnetic survey. A highly maneuverable underwater glider, ROUGHIE, was customized to carry an increased payload and reduce the vehicle’s magnetic signature. A sensor suite composed of a vector and scalar magnetometer was mounted in an external boom at the rear of the vehicle. The combined system was deployed in a constrained pool environment to detect seeded magnetic targets and create a magnetic map of the test area. Presented is a systematic magnetic disturbance reduction process, test procedure for anomaly mapping, and results from constrained operation featuring underwater motion capture system for ground truth localization. Validation in the noisy and constrained pool environment creates a trajectory towards affordable littoral magnetic anomaly mapping infrastructure. Such a marine sensor technology will be capable of extended operation in challenging areas while providing high-resolution, timely magnetic data to operators for automated detection and classification of marine objects.

The application of ground high-precision magnetic survey to the geology and mineral investigation in Huanghe Town area

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/660/1/012105 ◽

2021 ◽

Vol 660 (1) ◽

pp. 012105

Author(s):

Yuguo Lu ◽

Bin Xiong ◽

Yanhe Wang ◽

Xiaoqin Su

Keyword(s):

High Precision ◽

Magnetic Survey ◽

Town Area

A discussion concerning the floor of the northwest Indian Ocean - An area on the crest of the Carlsberg Ridge: petrology and magnetic survey

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1966.0007 ◽

1966 ◽

Vol 259 (1099) ◽

pp. 198-217 ◽

Cited By ~ 54

Keyword(s):

Remanent Magnetization ◽

Ultramafic Rocks ◽

Magnetic Survey ◽

Vector Fitting ◽

Uniform Magnetization ◽

Ocean Floor Spreading ◽

Carlsberg Ridge ◽

History Of ◽

Magnetic Gradients ◽

Basalt Glasses

Rocks collected in the vicinity of a transcurrent fault cutting the crest of the Ridge have been affected by brecciation and, in some cases, metamorphism and hydrothermal action. These processes have led to the formation of spilites from crystalline basalts, and ultramafic rocks from basalt glasses Further hydrothermal action has taken the form of replacement of some ultramafic rocks by quartz, ending in a nearly pure quartzite. The mineralogy is characteristic of greenschist facies meta-morphism. Fresh basalts were collected from a nearby hill, which seems to be a recent volcano post-dating the faulting and metamorphism. The magnetic survey reveals a marked parallelism between the anomalies and the trend of the ridge, regardless of bathymetry. Computations confirm that uniform magnetization of the material represented by the bathymetry can in no way simulate the observed anomalies. Application of the vector fitting technique suggests that the remanent magnetization of this material is often reversed and from this a very crude and simple model is developed to account for the observed anomalies. The model is consistent with an ocean floor spreading hypothesis and periodic reversals in the earth's magnetic field. If substantiated it would have important implications in deducing the history of the ocean basins. Above all it provides a plausible explanation to account for the magnetic gradients and amplitudes observed over ridges without implying improbable magnetic contrasts, structures, or changes in petrology.