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The Feasibility of Using Lidar-Derived Digital Elevation Models for Gravity Data Reduction

Open-File Report 2025-1019
Mineral Resources Program
By: , , , , , and 
https://doi.org/10.3133/ofr20251019

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Acknowledgments

The authors would like to thank Dr. Snehamoy Chatterjee of the Michigan Technological University for his helpful discussion of statistical data analysis; Joshua Nimetz of the U.S. Geological Survey (USGS) for his helpful discussion on lidar data acquisition, processing, and formats; and Anji Shah and Phil Brown of the USGS for their thorough reviews of our manuscript. Val Chandler of the Minnesota Geological Survey was an early proponent of using lidar-derived digital elevation models for gravity work and challenged us to undertake this study.

Abstract

Gravity data require submeter elevation accuracy for data processing, and differential global navigation satellite system (dGNSS) equipment is commonly used to acquire three-dimensional positional data to achieve such accuracy. However, lidar (light detection and ranging) data are commonly used to develop digital elevation models (DEMs) of Earth’s surface. Therefore, using elevations from lidar-derived DEMs for gravity-data acquisition and reduction may improve field efficiency and reduce cost. This study examines the feasibility of using DEMs for gravity-data reduction by comparing dGNSS elevation data from 435 gravity stations in Michigan, Wyoming, and Colorado with their respective DEM elevations. The results show that the average difference between DEM and dGNSS elevations is 13 centimeters (cm) and that 93 percent of those differences are less than 50 cm, even in areas with steep terrain. Because an elevation discrepancy of 50 cm corresponds to an error of roughly 0.1 milligals (mGal) in the simple Bouguer gravity anomaly, the results suggest that lidar-derived DEMs are a viable source for acquiring the elevation data needed to process gravity data, thus improving both the cost and efficiency of data collection for regional surveys where an accuracy of less than 1.0 mGal is desired.

Introduction

The gravity geophysical method is a useful, often essential, tool for mapping subsurface geology. Gravity data reduction (processing) relies heavily on accurate and precise elevation measurements, which are often achieved using high-precision (submeter) differential global navigation satellite system (dGNSS) equipment that can determine gravity-station elevations within less than 1 meter. This sort of “surveying grade” dGNSS equipment typically costs tens of thousands of dollars and requires the daily setup of a local base station that must be secured. If the requirement for expensive dGNSS equipment and the corresponding need for a local base station can be eliminated, gravity data acquisition would become less expensive and more efficient. This report examines the feasibility of using elevations taken from lidar-derived DEMs for use in the reduction of gravity data as a possible replacement for measurements that require the use of expensive dGNSS equipment. The assessment involves comparing gravity-station elevations acquired using high-precision dGNSS equipment with elevations sampled from lidar-derived DEMs at the same locations. Nondifferentially corrected horizontal coordinates provided by the dGNSS measurements were used to simulate the effect of data acquisition without using a GNSS base station.

Gravity Data Acquisition and Reduction

Gravity data are acquired using gravimeters, usually spring-type balances that measure relative gravity by the change of strain (length) on an internal spring (for example, Hinze and others [2012]). A change in gravity causes the displacement of a test mass within these devices that can be nullified by adjusting the spring length to compensate for the test mass displacement. The spring length needed to nullify the balance is then used to calculate the gravity at a specific location. Gravity measurements are taken relative to a base station, where the absolute value of the gravity field intensity is typically known to within 0.1 milligal (mGal). Measurements of variations in the Earth’s gravity field (anomalies) are produced by lateral variations of density within the subsurface (as in Hinze and others [2012]). The measured gravity field is affected by multiple factors, including time-varying factors (such as tides and instrument drift), latitude, elevation, the terrain surrounding the measurement locations (stations), and the density of the Earth. To isolate anomalies produced by local density variations relatable to geology, a series of corresponding corrections must be applied to the observed gravity (for example, Longman [1959] and Blakely [1995]). Accurate elevation measurements are crucial for calculating the free-air and Bouguer gravity anomalies. So, the quality of a gravity survey is heavily dependent on precise elevation control, as an elevation error of 50 centimeters (cm) results in a 0.1 mGal error in the simple Bouguer anomaly.

Lidar Acquisition and Processing

Lidar is a remote-sensing method that uses light as a pulsed laser to measure distances to the Earth from an airborne platform (for example, National Oceanic and Atmospheric Administration [NOAA], [2023]). Data are collected from an aircraft with three main components: a laser scanner unit, a global navigation satellite system (GNSS) unit, and an inertial measurement unit (IMU) (Habib and others, 2005; Hollaus and others, 2005; Reutebuch and others, 2005; Webster and Dias, 2006; Pfeifer and Briese, 2007; Liu, 2008). The laser scanner emits pulses around 1,000 nanometers at a near-infrared wavelength (for example, Elaksher [2016]) and contains a receiver that detects the time it takes for the pulsed laser to reach the Earth and return (fig. 1). These reflections are recorded as individual points that define a point cloud, which can be processed to represent locations on the surface of the Earth (Sugarbaker and others, 2014). The recorded reflections occur from vegetation, the ground surface, and even human-made objects (see Barber and Shortrudge [2004] and Stoker and others [2006]). Therefore, a critical step in lidar processing is ensuring that unwanted artifacts (nonground) are extracted from the data before DEM construction (Liu, 2008).

Ground data depicted as visual images before the scan and color-represented lidar data after the scan.
Figure 1.

A schematic of light detection and ranging (lidar) data acquisition, modified from National Oceanic and Atmospheric Administration (2012), showing an aircraft scanning the Earth’s surface with lidar and revealing lidar topography information while simultaneously receiving global navigation satellite system (GNSS) and inertial measurement unit data. The full scan angle (θ) from the aircraft and a single laser shot within that scan are shown. A GNSS base station is shown on Earth’s surface.

The GNSS unit records the aircraft’s trajectory, and the IMU measures the aircraft’s altitude; both directly influence the accuracy of the lidar points (Webster and Dias, 2006). Analysts supplement and validate the lidar data with ground-control checkpoints having known horizontal and vertical positions to ensure horizontal and vertical accuracy. Table 1 gives the minimum number of checkpoints recommended by the American Society for Photogrammetry and Remote Sensing (ASPRS) based on the area of the DEM being constructed; however, these checkpoints may be altered based on the desired quality level (QL) of the DEM (ASPRS, 2023).

Table 1.    

The minimum number of checkpoints recommended per square kilometer (km2) of a light detection and ranging survey from the American Society for Photogrammetry and Remote Sensing (2023).

[≤, less than or equal to]
Area (km2) Number of checkpoints
≤ 500 30
501–750 35
751–1,000 40
1,001–1,250 45
1,251–1,500 50
1,501–1,750 55
1,751–2,000 60
2,001–2,250 65
2,251–2,500 70
Table 1.    The minimum number of checkpoints recommended per square kilometer (km2) of a light detection and ranging survey from the American Society for Photogrammetry and Remote Sensing (2023).

The quality level (QL) of a lidar survey is determined by the nominal pulse spacing (NPS) and the vertical positional accuracy, as specified in table 2 (U. S. Geological Survey [USGS], undated.). QL2 lidar-derived DEMs were used for this analysis.

Table 2.    

The requirements for different quality level (QL) light detection and ranging (lidar) data; quality level 2 (QL2) are used in this report.

[This table is modified from the U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) (USGS, undated). cm, centimeter; DEM, digital elevation model; m, meter; NPD, nominal pulse density; NPS, nominal pulse spacing; pts per m2, points per square meter; RMSEz, root mean square error in the vertical (z) direction; QL, quality level; ≤, less than or equal to; ≥, greater than or equal to]
Quality level1 Data source Vertical accuracy RMSEz
(cm)		 Nominal pulse spacing
(m)		 Nominal pulse density
(pts per m2)		 DEM cell size
(m)
QL0 Lidar 5 ≤ 0.35 ≥ 8 0.5
QL1 Lidar 10 ≤ 0.35 ≥ 8 0.5
QL2 Lidar 10 ≤ 0.71 ≥ 2 1
QL3 Lidar 20 ≤ 1.41 ≥ 0.5 2
Table 2.    The requirements for different quality level (QL) light detection and ranging (lidar) data; quality level 2 (QL2) are used in this report.
1

Quality levels are explained in U.S. Geological Survey (undated).

Several methods can be used for extracting nonground points from the raw lidar point-cloud, such as triangulated irregular network (TIN) filtering, slope-based filtering, mathematical morphological filtering, interpolation-based filtering, and machine-learning-based filtering (Cai and others, 2020). The USGS 3D Elevation Program (3DEP) typically requires TIN filtering to assess both the vegetated and nonvegetated vertical accuracy of lidar data (USGS, 2024). TIN filtering uses a triangulation algorithm to create a surface model from the point-cloud data. The height of each point is compared with its neighbor within the triangle, and points having a significantly higher height than their neighbors are removed (Peucker and others, 1976). After extracting nonground points from the lidar data, a DEM is interpolated based on the remaining ground points. Interpolation is predicting values at an unsampled location using the measured values nearby (for example, Burrough and McDonnell [1998]). DEM interpolation typically uses inverse distance weighted (IDW), spline-based, or geostatistical methods (such as kriging) (Liu, 2008). Once the interpolation method is chosen, a DEM grid is constructed based on the QL of the data.

Study Design

To study the feasibility of using lidar-derived elevations for gravity-data reduction, we acquired dGNSS elevation data for 435 gravity stations in the Upper Peninsula of Michigan (237 stations, fig. 2A–C), the Wet Mountains of Colorado (59 stations, fig. 3A), and the Medicine Bow Mountains of Wyoming (139 stations, fig. 3B). For each station, Leica Viva GS16 GNSS equipment or a Trimble Geo7x handheld GNSS receiver was used to determine differentially corrected locations (latitude and longitude) and elevations, typically accurate to within 10 cm. To compute differential corrections for the Leica Viva GS16, a GNSS base station located within 25 kilometers (km) of the stations was used. For the Trimble Geo7x, the NOAA Continuously Operating Reference Stations located within 65 km of the gravity stations were used to correct the data differentially. Additionally, GNSS-derived locations were recorded without applying differential corrections to simulate data acquisition conditions without using a GNSS base station.

For the lidar comparisons, 1-meter DEM tiles (QL2) were obtained using the USGS LidarExplorer (USGS, 2022; USGS, 2023), the Michigan Technological University Geospatial Research Facility DEM downloader (Sanborn Map Company, Inc., 2020), or the Colorado Hazard Mapping & Risk MAP Portal (Merrick & Company, 2016; Quantum Spatial, Inc., 2020) and were “mosaiced” together in the ArcGIS Pro software package to encompass the entirety of each gravity survey.3 The nondifferentially corrected gravity station coordinates (North American Datum of 1983) were added to ArcGIS Pro, and the DEM was sampled at each station for comparison with the differentially corrected elevation provided by the dGNSS equipment. The flowchart shown in figure 4 describes each data acquisition, processing, and interpretation step. However, it should be noted that the lidar data were acquired and processed before this study.

3

Datasets are “mosaiced” or merged using the “Mosaic” tool in the ArcGIS Pro software package.

The location of the study area within the region is shown on each map.
Figure 2.

Three maps (A–C) showing the 237 gravity stations in the Upper Peninsula of Michigan for which location information was collected as part of regional gravity surveys. The stations overlay the mosaiced 1-meter (m) digital elevation model (DEM) rasters obtained from the U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) light detection and ranging (lidar) data in the National Map Downloader (USGS, 2022) or the Michigan Technological University Geospatial Research Facility DEM tool (Sanborn Map Company, Inc., 2020). (A) Map showing the 56 gravity stations in the Keweenaw Peninsula of Michigan (MI–KP0) where location data were collected with a Global Navigational Satellite System (GNSS) receiver. Elevation data are from 0 to 450 m. (B) Map showing the 94 gravity stations in the west-central Upper Peninsula of Michigan (MI–HR) where location information was collected with GNSS equipment. Elevation data are from 400 to 600 m. (C) Map showing the 87 gravity stations in the central Upper Peninsula of Michigan (MI–TM) where location information was collected with GNSS equipment. Elevation data are from 150 to 300 m. The prefixes discussed here—MI–KP0, MI–HR, and MI–TM—represent the location aspect of the gravity station numbers in tables 3, 4, and 7 (at the end of this report). ft, foot.

The location of the study area within the region is shown on each map.
Figure 3.

Two maps (A, B) showing the 198 gravity stations in the western United States (Wyoming and Colorado) for which location information was collected as part of regional gravity surveys. The stations overlay the mosaiced 1-meter (m) digital elevation model (DEM) rasters. Light detection and ranging (lidar) data were obtained from two sources. U.S. Geological Survey (USGS) 3D Elevation Program lidar data were retrieved from the USGS National Map Downloader (USGS, 2024). Lidar data from Merrick & Company (2016) and Quantum Spatial, Inc. (2020) were retrieved from the Colorado Hazard Mapping & Risk MAP Portal (Merrick & Company, 2016). (A) Map showing the 59 gravity stations in the Wet Mountains of Colorado (CO–WM) where location information was collected with Global Navigational Satellite System (GNSS) equipment. Elevation data are from 2,000 to 4,000 m. (B) Map showing the 139 gravity stations in the Medicine Bow Mountains of Wyoming (WY–MB) where location information was collected with GNSS equipment. Elevation data are from 2,000 to 4,000 m. The prefixes discussed here—CO–WM and WY–MB—represent the location aspect of the gravity station numbers in tables 5 and 6 (at the end of this report). ft, foot.

Three process steps shown for GNSS data, three steps shown for lidar data, and three process steps are common to both.
Figure 4.

A flowchart showing how global navigational satellite system (GNSS) positional data and light detection and ranging (lidar) data were acquired, processed, and prepared and then how the resulting data for both sets were selected, extracted, and interpreted. DEM, digital elevation model; NAD 83, North American Datum of 1983.

Results

The elevation differences between the dGNSS measurements and DEMs were consistently (93 percent) less than 50 cm, corresponding to a 0.1 mGal error in the simple Bouguer gravity anomaly. Horizontal and vertical positions for all 435 gravity stations are shown in tables 3–7 (at the end of the report) with their respective lidar-derived elevation and the differences between the GNSS and lidar-derived elevations. The distribution of differences between DEM and GNSS elevations is shown in figure 5A, and the distribution of their absolute differences is shown in figure 5B.

The mean difference between the GNSS and DEM-derived elevations is 13 cm with a standard deviation of 46 cm. Approximately 93 percent (N = 406) of the data points fall within 1 standard deviation of the mean (minimum –33 cm; maximum 59 cm). The lower limit for the 95 percent confidence interval is 9 cm, and the upper limit is 17 cm. A maximum positive difference of 3.9 meters (m) and a maximum negative difference of –2.1 m occur in the central Upper Peninsula. However, the mean elevation difference in the Upper Peninsula is 8 cm, a measure less than the average in Colorado and Wyoming (20 cm), which contain steep terrain. Overall, 97 percent (N = 423) of the 435 stations exhibit an elevation difference of less than 1 m. The statistical breakdown for each study area is shown in table 8.

Table 8.    

A statistical breakdown of each study area in this project that shows the average elevation difference observed and the number of points with a difference greater than 1 meter (m).

[UP, upper peninsula]

Location Mean elevation difference
(m)		 Standard deviation Minimum
(m)		 Maximum
(m)		 No. of points
>1 m elevation difference
Medicine Bow Mountains, Wyoming 0.25 0.37 –0.39 3.1 4
Wet Mountains, Colorado 0.11 0.53 –0.93 3.7 1
Keweenaw Peninsula, Michigan 0.26 0.47 –0.07 2.7 2
West-central UP, Michigan –0.07 0.17 –0.66 0.54 0
Central UP, Michigan 0.11 0.62 –2.1 3.9 5
Total UP, Michigan (less-steep terrain) 0.08 0.44 –2.1 3.9 7
Total Wyoming and Colorado (steep terrain) 0.20 0.42 –0.93 3.7 5
Table 8.    A statistical breakdown of each study area in this project that shows the average elevation difference observed and the number of points with a difference greater than 1 meter (m).
The distribution curve is also shown for both graphs.
Figure 5.

Two bar graphs (A, B) showing elevation distributions. (A) Bar graph that shows the distribution (mean = 0.13, standard deviation = 0.46) of elevation differences (global navigational satellite system–light detection and ranging [GNSS – lidar]) and indicates that 93 percent of the data fall within 1 standard deviation (σ) of the mean (μ) (13 centimeters [cm]). (B) Bar graph that shows the distribution (mean = 0.22, standard deviation = 0.42) of the absolute value of the elevation differences (|GNSS – lidar|) and a mean difference of 22 cm in the absolute differences observed within the data. %, percent; m, meter.

Discussion

Of the 435 gravity stations, 406 (approximately 93 percent) lidar-derived elevations fall within ±50 cm of the dGNSS elevations, meaning that their use would produce an error of less than 0.1 mGal in the simple Bouguer anomaly. Regional gravity surveys commonly focus on mapping anomalies greater than 1 mGal, so an error of 0.1 mGal is not a cause for concern in most cases. Moreover, most absolute base (reference) stations used for gravity-data reduction have an uncertainty of ±0.1 mGal (for example, Morelli and others [1972]). Therefore, this study shows that lidar-derived elevations are sufficiently accurate for regional gravity-data reduction, and, in most cases, their use produces errors comparable to the inherent absolute accuracy of standard regional gravity surveys. For detailed gravity surveys focused on smaller anomalies—those with an accuracy of less than 0.1 mGal—dGNSS equipment may be necessary.

Only 12 gravity stations (less than 3 percent) had elevation differences greater than 1 m between dGNSS and lidar-derived elevations. Seven were in the Upper Peninsula of Michigan, four were in the Medicine Bow Mountains of Wyoming, and one was in the Wet Mountains of Colorado. To identify the sources of these discrepancies, we examined the elevation differences between the lidar-derived elevations and dGNSS elevations using the differentially corrected horizontal coordinates in the Medicine Bow Mountains. The average elevation difference between the measurements was roughly 1-cm less than when the nondifferentially corrected coordinates were used, and the same four stations showed an elevation difference of greater than 1 m. This observation indicates that the four largest elevation discrepancies are not likely related to the lack of differential processing of the horizontal coordinates. Instead, these discrepancies may result from dense vegetation causing a multipath in the GNSS signal, a locally steep elevation gradient, or an unknown error in the dGNSS-derived elevations.

Recommended Field Practices

The use of several recommendations may optimize positional data acquisition for gravity data processing and yield acceptable uncertainty in simple Bouguer gravity values. GNSS equipment (for example, a handheld, non-dGNSS unit) with the ability to detect both Global Positioning System (GPS) and Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS)4 satellites is recommended for obtaining the best possible horizontal position data, especially at higher latitudes where GPS readings are less accurate. Horizontal positional errors may result in the gravity station being mislocated by more than several meters, thus producing elevation inaccuracies. For this reason, placing gravity stations in areas more than 5 m away from steep topographic slopes (such as a locally flat surface) is recommended.

4

The “Global Navigation Satellite System” is a Russian satellite-based navigation system that provides position information.

The reduction or elimination of multipaths is also necessary for optimizing positional accuracy during data acquisition. A multipath can result from the primary GNSS signal reflecting off buildings, vegetation, or mountains, or from atmospheric scattering. A reduction of this effect can be achieved by placing the GNSS antenna in an elevated position, such as on the roof of a vehicle or a range pole and away from areas with dense vegetation. Placing stations on small platforms above the ground’s surface can also cause inaccuracies in the lidar-derived elevation and should be avoided.

Conclusion

This study evaluated whether lidar-derived DEMs could serve as elevation control for gravity surveys to reduce cost and improve field efficiency. Elevation data from 435 gravity stations in the Upper Peninsula of Michigan, the Medicine Bow Mountains of Wyoming, and the Wet Mountains of Colorado were compared with elevations from a 1-m horizontal-resolution DEM for each station. An average difference of 13 cm between dGNSS and DEM elevations was observed, with a standard deviation of 46 cm. Over 93 percent of the DEM data were within 50 cm of GNSS data, corresponding to a simple Bouguer gravity error of approximately 0.1 mGal.

These results indicate that lidar-derived DEMs provide acceptable elevation control for gravity data reduction, particularly for regional gravity surveys where anomalies of interest are usually greater than 1 mGal in amplitude. In detailed surveys requiring greater accuracy and precision, other means of determining elevations may be required. Twelve stations exhibited elevation differences between dGNSS and DEM data greater than 1 m. The source of this relatively rare discrepancy is unknown but may be related to dense vegetation cover, locally steep elevation gradients, or an unknown error in the dGNSS elevations. This study suggests that using QL2 lidar-derived DEMs for gravity-data reduction is acceptable for most regional surveys.

Tables 3–7

Table 3.    

Location information for the 94 gravity stations located at west-central Upper Peninsula of Michigan (MI–HR) from Drenth and Others (2024).

[“Gravity station” refers to a unique identifier that is based on the station number used in the data source for this table. “UC LAT” and “UC LON” refer to the horizontal coordinates before differential correction. “DC LAT” and “DC LON” refer to the differentially corrected horizontal coordinates. “DGNSS ELEV” refers to the elevation data from the differential global navigation satellite system (dGNSS) equipment from the differentially corrected coordinates. “LIDAR ELEV” refers to the light detection and ranging (lidar) derived elevation from the 1-meter (m) digital elevation model (DEM). “ELEV DIFF” refers to the elevation difference (dGNSS – lidar), and “ABS ELEV DIFF” refers to the absolute value of this difference. NAD 83, North American Datum of 1983; NAVD 88, North American Vertical Datum of 1988]
Gravity station UC LAT
(NAD 83)		 UC LON
(NAD 83)		 DC LAT
(NAD 83)		 DC LON
(NAD 83)		 DGNSS
ELEV (m)
(NAVD 88)		 LIDAR
ELEV (m)
(NAVD 88)		 ELEV
DIFF
(m)		 ABS ELEV
DIFF
(m)
MI–HR209 46.42494 –88.16299 46.42493 –88.16300 523.87 523.74 0.13 0.13
MI–HR210 46.43683 –88.16355 46.43681 –88.16355 538.11 538.10 0.01 0.01
MI–HR211 46.44739 –88.16216 46.44738 –88.16216 531.44 531.10 0.35 0.35
MI–HR212 46.46448 –88.17829 46.46448 –88.17830 544.78 544.73 0.04 0.04
MI–HR213 46.43243 –88.18091 46.43242 –88.18092 525.93 525.81 0.12 0.12
MI–HR214 46.43118 –88.19405 46.43117 –88.19406 514.27 514.27 0.00 0.00
MI–HR215 46.42438 –88.21213 46.42439 –88.21215 515.77 515.53 0.24 0.24
MI–HR216 46.42267 –88.22513 46.42266 –88.22513 536.88 536.80 0.09 0.09
MI–HR217 46.41882 –88.24124 46.41881 –88.24127 534.57 534.72 –0.15 0.15
MI–HR218 46.43243 –88.22989 46.43243 –88.22991 543.09 543.01 0.08 0.08
MI–HR219 46.44121 –88.23626 46.44121 –88.23627 540.62 540.19 0.43 0.43
MI–HR220 46.45163 –88.23310 46.45164 –88.23311 534.12 534.74 –0.62 0.62
MI–HR221 46.45329 –88.21923 46.45330 –88.21922 525.97 525.43 0.54 0.54
MI–HR222 46.43917 –88.21494 46.43918 –88.21494 528.55 528.60 –0.05 0.05
MI–HR223 46.44226 –88.18349 46.44227 –88.18349 529.38 529.38 0.00 0.00
MI–HR239 46.44133 –88.08456 46.44131 –88.08455 510.37 510.46 –0.10 0.10
MI–HR240 46.44881 –88.07866 46.44879 –88.07865 511.92 511.90 0.02 0.02
MI–HR241 46.46879 –88.08052 46.46877 –88.08051 478.68 478.89 –0.21 0.21
MI–HR242 46.45943 –88.08535 46.45941 –88.08534 472.61 472.67 –0.06 0.06
MI–HR243 46.45848 –88.09835 46.45848 –88.09833 479.39 479.48 –0.09 0.09
MI–HR244 46.46113 –88.10863 46.46113 –88.10862 498.09 498.04 0.06 0.06
MI–HR245 46.46627 –88.11848 46.46626 –88.11848 521.55 521.60 –0.05 0.05
MI–HR246 46.47889 –88.12047 46.47888 –88.12046 525.69 525.75 –0.06 0.06
MI–HR247 46.45086 –88.10303 46.45085 –88.10303 492.13 492.27 –0.14 0.14
MI–HR248 46.44016 –88.11112 46.44014 –88.11112 486.16 486.13 0.02 0.02
MI–HR249 46.43465 –88.12686 46.43464 –88.12685 508.44 508.33 0.11 0.11
MI–HR250 46.44574 –88.12259 46.44573 –88.12259 508.40 508.40 0.00 0.00
MI–HR251 46.45507 –88.12062 46.45507 –88.12063 512.48 512.41 0.08 0.08
MI–HR252 46.45011 –88.06530 46.45011 –88.06529 471.30 471.16 0.14 0.14
MI–HR253 46.44357 –88.05018 46.44357 –88.05017 465.11 465.32 –0.21 0.21
MI–HR254 46.42801 –88.05931 46.42801 –88.05930 497.72 497.72 0.00 0.00
MI–HR255 46.43435 –88.03451 46.43434 –88.03450 457.50 457.70 –0.20 0.20
MI–HR256 46.42357 –88.02001 46.42358 –88.02000 457.56 457.47 0.09 0.09
MI–HR257 46.41524 –88.00702 46.41523 –88.00701 461.07 461.20 –0.13 0.13
MI–HR258 46.43268 –88.09584 46.43266 –88.09583 519.07 519.20 –0.13 0.13
MI–HR259 46.42517 –88.10726 46.42517 –88.10726 509.49 509.43 0.06 0.06
MI–HR260 46.41580 –88.11487 46.41580 –88.11487 511.05 511.11 –0.07 0.07
MI–HR261 46.40543 –88.11949 46.40543 –88.11949 503.56 503.58 –0.02 0.02
MI–HR262 46.40569 –88.11962 46.40569 –88.11961 503.74 503.75 0.00 0.00
MI–HR263 46.39486 –88.11466 46.39486 –88.11466 490.43 490.56 –0.13 0.13
MI–HR265 46.42661 –88.09738 46.42660 –88.09738 524.72 524.96 –0.24 0.24
MI–HR266 46.41892 –88.08438 46.41892 –88.08436 508.71 508.78 –0.07 0.07
MI–HR267 46.43559 –88.05164 46.43558 –88.05165 499.46 499.57 –0.11 0.11
MI–HR268 46.41399 –88.02718 46.41398 –88.02718 475.55 475.52 0.04 0.04
MI–HR269 46.41310 –88.01249 46.41309 –88.01248 472.11 472.25 –0.13 0.13
MI–HR270 46.41278 –87.99475 46.41277 –87.99474 457.07 457.03 0.04 0.04
MI–HR271 46.40503 –87.98644 46.40502 –87.98643 456.36 456.40 –0.04 0.04
MI–HR272 46.39359 –87.99155 46.39358 –87.99154 462.14 462.16 –0.01 0.01
MI–HR273 46.39923 –88.01748 46.39922 –88.01748 457.80 457.90 –0.10 0.10
MI–HR274 46.38052 –88.02036 46.38051 –88.02037 461.31 461.31 0.00 0.00
MI–HR275 46.38799 –88.00558 46.38799 –88.00558 456.66 456.70 –0.04 0.04
MI–HR276 46.39172 –88.09548 46.39171 –88.09546 505.30 505.39 –0.09 0.09
MI–HR277 46.39956 –88.08134 46.39956 –88.08134 514.50 514.63 –0.12 0.12
MI–HR278 46.39919 –88.06436 46.39920 –88.06434 498.56 498.47 0.09 0.09
MI–HR279 46.40759 –88.05725 46.40758 –88.05723 488.88 488.88 0.01 0.01
MI–HR280 46.41484 –88.06662 46.41484 –88.06661 493.27 493.31 –0.04 0.04
MI–HR281 46.40704 –88.04444 46.40703 –88.04443 477.41 477.68 –0.27 0.27
MI–HR282 46.38617 –88.04290 46.38617 –88.04290 474.39 474.54 –0.15 0.15
MI–HR283 46.39784 –88.04632 46.39783 –88.04632 476.50 476.69 –0.18 0.18
MI–HR284 46.38457 –88.08025 46.38456 –88.08025 507.73 507.89 –0.16 0.16
MI–HR285 46.37563 –88.07300 46.37561 –88.07301 501.87 502.09 –0.22 0.22
MI–HR286 46.37335 –88.05530 46.37333 –88.05530 482.75 482.83 –0.08 0.08
MI–HR287 46.37545 –88.03577 46.37543 –88.03578 471.54 471.62 –0.08 0.08
MI–HR288 46.37665 –88.08606 46.37664 –88.08606 507.56 507.64 –0.08 0.08
MI–HR289 46.37673 –88.09903 46.37672 –88.09903 495.34 495.37 –0.03 0.03
MI–HR290 46.37274 –88.10606 46.37273 –88.10606 488.82 488.87 –0.05 0.05
MI–HR291 46.37188 –88.11852 46.37187 –88.11853 479.97 480.05 –0.08 0.08
MI–HR301 46.41593 –87.98031 46.41594 –87.98032 482.42 482.41 0.01 0.01
MI–HR302 46.41762 –87.96272 46.41761 –87.96274 474.48 474.78 –0.30 0.30
MI–HR303 46.42835 –87.95810 46.42835 –87.95812 466.70 466.94 –0.24 0.24
MI–HR304 46.42658 –87.93938 46.42657 –87.93940 465.76 465.84 –0.08 0.08
MI–HR305 46.42620 –87.92179 46.42620 –87.92181 462.74 462.75 0.00 0.00
MI–HR306 46.42973 –87.90791 46.42970 –87.90793 461.32 461.42 –0.11 0.11
MI–HR307 46.44103 –87.91421 46.44099 –87.91423 477.03 476.99 0.04 0.04
MI–HR308 46.42258 –87.89031 46.42254 –87.89032 456.78 456.92 –0.14 0.14
MI–HR309 46.42578 –87.87663 46.42575 –87.87665 459.60 459.74 –0.15 0.15
MI–HR310 46.41063 –87.89066 46.41060 –87.89066 457.74 457.91 –0.17 0.17
MI–HR311 46.41775 –87.92782 46.41772 –87.92783 460.52 460.70 –0.18 0.18
MI–HR312 46.40566 –87.92574 46.40565 –87.92576 464.99 465.32 –0.33 0.33
MI–HR313 46.40483 –87.96428 46.40484 –87.96430 465.96 466.39 –0.43 0.43
MI–HR314 46.39421 –87.95238 46.39421 –87.95241 467.12 467.40 –0.27 0.27
MI–HR315 46.38814 –87.93001 46.38815 –87.93003 465.65 465.94 –0.29 0.29
MI–HR316 46.38068 –87.91778 46.38070 –87.91779 459.97 460.14 –0.16 0.16
MI–HR317 46.36793 –87.90407 46.36795 –87.90407 454.28 454.45 –0.17 0.17
MI–HR318 46.35638 –87.89669 46.35640 –87.89667 456.48 457.15 –0.66 0.66
MI–HR319 46.34743 –87.87883 46.34744 –87.87881 451.22 451.53 –0.31 0.31
MI–HR320 46.33948 –87.89772 46.33949 –87.89771 454.00 454.09 –0.09 0.09
MI–HR321 46.34497 –87.91396 46.34498 –87.91394 458.56 458.65 –0.09 0.09
MI–HR322 46.34791 –87.93149 46.34791 –87.93146 452.12 452.42 –0.30 0.30
MI–HR323 46.36046 –87.93067 46.36046 –87.93065 455.94 456.20 –0.26 0.26
MI–HR324 46.37647 –87.93349 46.37646 –87.93346 460.19 460.06 0.14 0.14
MI–HR325 46.40201 –87.99925 46.40202 –87.99923 481.08 481.11 –0.03 0.03
MI–HR326 46.37824 –87.98663 46.37825 –87.98662 451.77 451.76 0.01 0.01
MI–HR327 46.36282 –87.97087 46.36284 –87.97084 447.92 448.19 –0.27 0.27
Table 3.    Location information for the 94 gravity stations located at west-central Upper Peninsula of Michigan (MI–HR) from Drenth and Others (2024).

Table 4.    

Location information for the 87 gravity stations located on the central Upper Peninsula of Michigan (MI–TM) from Drenth and others (2024).

[“Gravity station” refers to a unique identifier that is based on the station number used in the data source for this table. “UC LAT” and “UC LON” refer to the horizontal coordinates before differential correction. “DC LAT” and “DC LON” refer to the differentially corrected horizontal coordinates. “DGNSS ELEV” refers to the elevation data from the differential global navigation satellite system (dGNSS) equipment from the differentially corrected coordinates. “LIDAR ELEV” refers to the light detection and ranging (lidar) derived elevation from the 1-meter (m) digital elevation model (DEM). “ELEV DIFF” refers to the elevation difference (dGNSS – lidar), and “ABS ELEV DIFF” refers to the absolute value of this difference. NAD 83, North American Datum of 1983; NAVD 88, North American Vertical Datum of 1988]
Gravity station UC LAT
(NAD 83)		 UC LON
(NAD 83)		 DC LAT
(NAD 83)		 DC LON
(NAD 83)		 DGNSS
ELEV (m)
(NAVD 88)		 LIDAR
ELEV (m)
(NAVD 88)		 ELEV
DIFF
(m)		 ABS ELEV
DIFF
(m)
MI–TM001 46.05761 –86.76523 46.05760 –86.76523 228.46 228.55 –0.10 0.10
MI–TM002 46.05005 –86.77984 46.05004 –86.77984 237.26 237.29 –0.04 0.04
MI–TM003 46.04471 –86.79793 46.04470 –86.79792 235.38 235.29 0.09 0.09
MI–TM004 46.03561 –86.82491 46.03561 –86.82492 231.49 231.54 –0.05 0.05
MI–TM005 46.05917 –86.82250 46.05919 –86.82249 231.44 233.53 –2.09 2.09
MI–TM006 46.10298 –86.76241 46.10298 –86.76243 240.67 240.74 –0.07 0.07
MI–TM007 46.12079 –86.75999 46.12079 –86.76001 250.59 250.52 0.07 0.07
MI–TM008 46.13699 –86.75775 46.13700 –86.75778 243.03 243.05 –0.01 0.01
MI–TM009 46.14718 –86.78123 46.14719 –86.78124 240.63 240.60 0.02 0.02
MI–TM010 46.14721 –86.80917 46.14722 –86.80918 242.80 242.83 –0.02 0.02
MI–TM011 46.15373 –86.83689 46.15373 –86.83691 237.25 237.29 –0.04 0.04
MI–TM012 46.13682 –86.83782 46.13683 –86.83782 248.12 247.11 1.01 1.01
MI–TM013 46.11941 –86.83631 46.11941 –86.83633 243.01 243.11 –0.10 0.10
MI–TM014 46.10464 –86.83439 46.10466 –86.83442 228.64 228.71 –0.07 0.07
MI–TM015 46.09690 –86.86844 46.09690 –86.86845 214.65 214.68 –0.04 0.04
MI–TM016 46.08374 –86.84393 46.08374 –86.84394 231.24 231.25 –0.02 0.02
MI–TM017 46.06476 –86.85307 46.06475 –86.85306 232.13 231.87 0.26 0.26
MI–TM018 46.04313 –86.85153 46.04314 –86.85154 230.66 230.67 –0.01 0.01
MI–TM019 46.02522 –86.86199 46.02522 –86.86200 224.94 225.03 –0.09 0.09
MI–TM020 46.02190 –86.83746 46.02190 –86.83748 228.33 228.41 –0.08 0.08
MI–TM021 46.09679 –86.77856 46.09679 –86.77857 243.10 242.94 0.16 0.16
MI–TM022 46.07565 –86.77473 46.07564 –86.77473 237.34 237.23 0.11 0.11
MI–TM023 46.04142 –86.75639 46.04141 –86.75639 215.18 215.18 0.00 0.00
MI–TM024 46.02985 –86.73892 46.02984 –86.73893 231.27 231.18 0.09 0.09
MI–TM025 46.03102 –86.71163 46.03102 –86.71163 229.00 228.94 0.06 0.06
MI–TM026 46.04420 –86.71386 46.04421 –86.71387 230.28 230.34 –0.07 0.07
MI–TM027 46.02166 –86.69368 46.02168 –86.69369 230.49 230.47 0.02 0.02
MI–TM028 46.01128 –86.67806 46.01129 –86.67808 230.95 230.94 0.01 0.01
MI–TM029 46.01631 –86.65150 46.01633 –86.65150 229.18 229.18 0.00 0.00
MI–TM030 46.02011 –86.62713 46.02013 –86.62713 238.58 234.70 3.89 3.89
MI–TM031 46.03034 –86.60562 46.03034 –86.60562 232.86 232.85 0.01 0.01
MI–TM032 46.04037 –86.58267 46.04037 –86.58268 233.50 233.46 0.04 0.04
MI–TM033 46.04585 –86.56003 46.04586 –86.56004 233.23 233.06 0.17 0.17
MI–TM034 46.04844 –86.52518 46.04844 –86.52518 231.52 231.51 0.01 0.01
MI–TM035 46.06206 –86.54437 46.06206 –86.54437 234.53 234.51 0.02 0.02
MI–TM036 46.07869 –86.54662 46.07871 –86.54663 237.41 237.31 0.10 0.10
MI–TM037 46.09413 –86.54977 46.09414 –86.54978 239.60 239.56 0.04 0.04
MI–TM038 46.11218 –86.55485 46.11219 –86.55486 244.43 244.38 0.05 0.05
MI–TM039 46.13041 –86.55865 46.13043 –86.55866 247.42 247.39 0.02 0.02
MI–TM040 46.14352 –86.55224 46.14354 –86.55226 255.16 255.02 0.13 0.13
MI–TM041 46.15762 –86.55333 46.15763 –86.55333 253.88 253.87 0.01 0.01
MI–TM042 46.15343 –86.58112 46.15343 –86.58114 242.02 242.12 –0.10 0.10
MI–TM043 46.15213 –86.60946 46.15214 –86.60948 240.03 240.05 –0.02 0.02
MI–TM044 46.07875 –86.74031 46.07874 –86.74032 237.59 236.63 0.95 0.95
MI–TM045 46.07712 –86.69008 46.07711 –86.69009 278.00 278.33 –0.32 0.32
MI–TM046 46.09977 –86.67117 46.09976 –86.67117 249.36 249.29 0.07 0.07
MI–TM047 46.11141 –86.67072 46.11143 –86.67073 239.36 239.24 0.11 0.11
MI–TM048 46.06748 –86.71794 46.06747 –86.71797 231.27 231.28 0.00 0.00
MI–TM049 46.07899 –86.72260 46.07900 –86.72261 235.34 235.34 0.00 0.00
MI–TM050 46.06587 –86.74520 46.06587 –86.74521 223.32 223.30 0.02 0.02
MI–TM051 46.02779 –86.66780 46.02781 –86.66781 242.08 242.04 0.04 0.04
MI–TM052 46.04770 –86.65981 46.04770 –86.65981 249.52 249.51 0.01 0.01
MI–TM053 46.04221 –86.63906 46.04224 –86.63907 240.68 240.27 0.41 0.41
MI–TM054 46.06501 –86.64277 46.06502 –86.64278 245.66 245.55 0.11 0.11
MI–TM055 46.08670 –86.64203 46.08671 –86.64204 248.09 248.09 0.00 0.00
MI–TM056 46.10423 –86.63742 46.10425 –86.63741 253.69 252.71 0.98 0.98
MI–TM057 46.16162 –86.75468 46.16161 –86.75469 245.85 245.96 –0.12 0.12
MI–TM058 46.17326 –86.72937 46.17326 –86.72939 241.60 241.64 –0.04 0.04
MI–TM059 46.15155 –86.72839 46.15156 –86.72840 241.30 241.38 –0.09 0.09
MI–TM060 46.12253 –86.69312 46.12254 –86.69314 258.60 258.57 0.04 0.04
MI–TM061 46.13349 –86.68783 46.13351 –86.68784 239.11 239.13 –0.02 0.02
MI–TM062 46.14831 –86.70171 46.14833 –86.70173 237.16 237.11 0.05 0.05
MI–TM063 46.16396 –86.69830 46.16397 –86.69831 238.12 238.16 –0.04 0.04
MI–TM064 46.15843 –86.67672 46.15844 –86.67673 255.73 255.73 –0.01 0.01
MI–TM065 46.16060 –86.65028 46.16063 –86.65029 245.13 245.13 0.01 0.01
MI–TM066 46.14994 –86.62531 46.14995 –86.62532 259.00 259.06 –0.06 0.06
MI–TM067 46.12999 –86.60514 46.13001 –86.60516 259.66 258.78 0.88 0.88
MI–TM068 46.13003 –86.57811 46.13004 –86.57811 251.35 251.37 –0.02 0.02
MI–TM069 46.11426 –86.58261 46.11428 –86.58263 248.29 248.27 0.02 0.02
MI–TM070 46.11179 –86.60224 46.11181 –86.60225 252.11 252.11 0.00 0.00
MI–TM071 46.10062 –86.58400 46.10063 –86.58401 245.12 245.04 0.09 0.09
MI–TM072 46.08423 –86.59097 46.08424 –86.59097 240.72 240.70 0.02 0.02
MI–TM073 46.07043 –86.57232 46.07044 –86.57232 236.64 236.62 0.02 0.02
MI–TM074 46.05627 –86.59073 46.05627 –86.59074 235.12 235.84 –0.71 0.71
MI–TM075 46.11936 –86.63511 46.11935 –86.63514 243.36 243.68 –0.32 0.32
MI–TM076 46.14429 –86.65346 46.14430 –86.65349 243.00 242.59 0.41 0.41
MI–TM077 46.14126 –86.63864 46.14127 –86.63868 252.68 251.23 1.45 1.45
MI–TM078 46.12989 –86.80151 46.12989 –86.80151 245.00 245.02 –0.02 0.02
MI–TM079 46.16822 –86.83967 46.16821 –86.83969 239.68 239.76 –0.08 0.08
MI–TM080 46.18263 –86.83808 46.18263 –86.83810 251.87 248.97 2.90 2.90
MI–TM081 46.19654 –86.83722 46.19654 –86.83725 247.93 247.95 –0.03 0.03
MI–TM082 46.16161 –86.79492 46.16161 –86.79493 246.17 246.19 –0.02 0.02
MI–TM083 46.17095 –86.77776 46.17096 –86.77777 245.68 245.66 0.02 0.02
MI–TM084 46.18688 –86.78758 46.18689 –86.78760 245.01 245.08 –0.07 0.07
MI–TM085 46.17720 –86.75986 46.17722 –86.75988 241.53 241.41 0.12 0.12
MI–TM086 46.19373 –86.77394 46.19374 –86.77395 245.13 245.18 –0.05 0.05
MI–TM087 46.20733 –86.79234 46.20736 –86.79234 248.92 248.74 0.19 0.19
Table 4.    Location information for the 87 gravity stations located on the central Upper Peninsula of Michigan (MI–TM) from Drenth and others (2024).

Table 5.    

Location information for the 139 gravity stations located on the Medicine Bow Mountains of Wyoming (WY–MB) from Brown and others (2025).

[“Gravity station” refers to a unique identifier that is based on the station number used in the data source for this table. “UC LAT” and “UC LON” refer to the horizontal coordinates before differential correction. “DC LAT” and “DC LON” refer to the differentially corrected horizontal coordinates. “DGNSS ELEV” refers to the elevation data from the differential global navigation satellite system (dGNSS) equipment from the differentially corrected coordinates. “LIDAR ELEV” refers to the light detection and ranging (lidar) derived elevation from the 1-meter (m) digital elevation model (DEM). “ELEV DIFF” refers to the elevation difference (dGNSS – lidar), and “ABS ELEV DIFF” refers to the absolute value of this difference. NAD 83, North American Datum of 1983; NAVD 88, North American Vertical Datum of 1988]
Gravity station UC LAT
(NAD 83)		 UC LON
(NAD 83)		 DC LAT
(NAD 83)		 DC LON
(NAD 83)		 DGNSS
ELEV (m)
(NAVD 88)		 LIDAR
ELEV (m)
(NAVD 88)		 ELEV
DIFF
(m)		 ABS ELEV
DIFF
(m)
WY–MB501 41.19046 –106.11896 41.19047 –106.11896 2460.88 2460.79 0.09 0.09
WY–MB502 41.19209 –106.09834 41.19209 –106.09833 2429.51 2429.49 0.02 0.02
WY–MB503 41.18895 –106.08313 41.18895 –106.08313 2437.69 2437.67 0.02 0.02
WY–MB504 41.17132 –106.06800 41.17133 –106.06801 2500.66 2500.68 –0.02 0.02
WY–MB505 41.16023 –106.05934 41.16023 –106.05934 2472.42 2472.48 –0.06 0.06
WY–MB506 41.15066 –106.05078 41.15065 –106.05078 2442.59 2442.57 0.02 0.02
WY–MB507 41.12864 –106.00738 41.12862 –106.00738 2275.38 2275.50 –0.12 0.12
WY–MB508 41.14603 –105.97609 41.14602 –105.97608 2262.97 2263.02 –0.05 0.05
WY–MB509 41.15448 –105.96188 41.15447 –105.96188 2258.65 2258.61 0.03 0.03
WY–MB510 41.17454 –105.96686 41.17453 –105.96686 2247.40 2247.43 –0.03 0.03
WY–MB511 41.18156 –105.98720 41.18155 –105.98720 2282.29 2282.41 –0.12 0.12
WY–MB512 41.20351 –106.08888 41.20350 –106.08889 2410.12 2410.13 –0.02 0.02
WY–MB513 41.21824 –106.08941 41.21823 –106.08941 2391.92 2391.99 –0.07 0.07
WY–MB514 41.15853 –106.14494 41.15853 –106.14494 2795.83 2795.68 0.15 0.15
WY–MB515 41.14441 –106.16480 41.14441 –106.16481 2779.63 2779.50 0.13 0.13
WY–MB516 41.13696 –106.17559 41.13695 –106.17559 2758.67 2758.61 0.06 0.06
WY–MB517 41.14246 –106.32488 41.14245 –106.32489 2753.32 2753.25 0.07 0.07
WY–MB518 41.13765 –106.28225 41.13764 –106.28225 2858.08 2857.98 0.09 0.09
WY–MB519 41.12641 –106.30779 41.12640 –106.30779 2750.82 2750.57 0.25 0.25
WY–MB520 41.23346 –106.08523 41.23346 –106.08524 2390.43 2390.38 0.06 0.06
WY–MB521 41.25531 –106.07788 41.25530 –106.07789 2398.72 2398.82 –0.10 0.10
WY–MB522 41.26883 –106.07623 41.26882 –106.07624 2377.67 2377.53 0.14 0.14
WY–MB523 41.37340 –106.14062 41.37340 –106.14062 2992.11 2991.83 0.28 0.28
WY–MB524 41.38964 –106.13893 41.38964 –106.13892 3011.35 3011.26 0.09 0.09
WY–MB525 41.39842 –106.15353 41.39843 –106.15353 3011.69 3011.50 0.19 0.19
WY–MB526 41.40553 –106.13729 41.40554 –106.13730 2993.47 2993.19 0.28 0.28
WY–MB527 41.42013 –106.13554 41.42014 –106.13554 2948.85 2948.73 0.13 0.13
WY–MB528 41.43273 –106.14276 41.43274 –106.14277 2951.91 2951.76 0.16 0.16
WY–MB529 41.44584 –106.12669 41.44585 –106.12670 2859.09 2858.94 0.15 0.15
WY–MB530 41.45834 –106.13831 41.45835 –106.13831 2819.46 2819.35 0.11 0.11
WY–MB531 41.46409 –106.12843 41.46408 –106.12843 2728.25 2726.51 1.74 1.74
WY–MB532 41.47037 –106.13498 41.47037 –106.13499 2712.18 2711.95 0.22 0.22
WY–MB533 41.44986 –106.14798 41.44985 –106.14799 3003.16 3002.90 0.26 0.26
WY–MB534 41.46325 –106.16424 41.46323 –106.16423 3002.84 3000.83 2.01 2.01
WY–MB535 41.35344 –106.14914 41.35343 –106.14915 3004.88 3004.53 0.36 0.36
WY–MB536 41.34814 –106.13838 41.34813 –106.13839 2988.23 2988.12 0.11 0.11
WY–MB537 41.34938 –106.12493 41.34936 –106.12494 2934.99 2935.39 –0.39 0.39
WY–MB538 41.36627 –106.15873 41.36628 –106.15873 2911.80 2911.48 0.33 0.33
WY–MB539 41.35579 –106.16766 41.35579 –106.16765 2783.06 2782.97 0.09 0.09
WY–MB540 41.34026 –106.16665 41.34026 –106.16665 2715.32 2715.31 0.01 0.01
WY–MB541 41.32412 –106.15787 41.32412 –106.15788 2591.96 2591.90 0.06 0.06
WY–MB542 41.28275 –106.10119 41.28275 –106.10119 2398.06 2398.07 –0.01 0.01
WY–MB543 41.22071 –106.07606 41.22071 –106.07605 2424.21 2424.16 0.04 0.04
WY–MB544 41.29736 –106.09520 41.29734 –106.09519 2421.13 2421.07 0.06 0.06
WY–MB545 41.31386 –106.13360 41.31385 –106.13360 2503.76 2503.76 0.00 0.00
WY–MB546 41.30799 –106.19738 41.30798 –106.19738 2918.25 2918.09 0.16 0.16
WY–MB547 41.30010 –106.21714 41.30009 –106.21715 3031.58 3031.27 0.31 0.31
WY–MB548 41.30087 –106.23800 41.30087 –106.23801 3051.26 3050.86 0.40 0.40
WY–MB549 41.31434 –106.25226 41.31435 –106.25228 3175.54 3175.29 0.26 0.26
WY–MB550 41.29642 –106.25626 41.29643 –106.25626 3037.98 3037.74 0.24 0.24
WY–MB551 41.29071 –106.27609 41.29071 –106.27609 3074.98 3074.79 0.18 0.18
WY–MB552 41.28869 –106.23471 41.28869 –106.23470 2960.95 2960.86 0.09 0.09
WY–MB553 41.36680 –106.17763 41.36680 –106.17764 2863.04 2862.91 0.13 0.13
WY–MB554 41.37821 –106.18809 41.37821 –106.18811 2961.79 2961.66 0.13 0.13
WY–MB555 41.39324 –106.19073 41.39322 –106.19074 3036.08 3035.80 0.28 0.28
WY–MB556 41.40661 –106.19289 41.40661 –106.19292 3071.54 3071.25 0.29 0.29
WY–MB557 41.41760 –106.20245 41.41760 –106.20246 3053.63 3053.41 0.22 0.22
WY–MB558 41.43099 –106.19507 41.43097 –106.19507 2995.17 2994.94 0.23 0.23
WY–MB559 41.44403 –106.20143 41.44402 –106.20143 2984.57 2984.45 0.12 0.12
WY–MB560 41.45465 –106.21267 41.45464 –106.21267 2990.60 2990.29 0.31 0.31
WY–MB561 41.47833 –106.20236 41.47833 –106.20237 2948.91 2948.56 0.35 0.35
WY–MB562 41.46460 –106.21658 41.46458 –106.21659 2981.29 2980.69 0.60 0.60
WY–MB563 41.45965 –106.23325 41.45964 –106.23326 2973.63 2972.78 0.84 0.84
WY–MB564 41.47559 –106.23098 41.47558 –106.23098 3071.38 3071.14 0.24 0.24
WY–MB565 41.48384 –106.21930 41.48382 –106.21931 3006.00 3005.99 0.01 0.01
WY–MB566 41.46829 –106.24426 41.46830 –106.24427 3078.87 3078.57 0.30 0.30
WY–MB567 41.46409 –106.25900 41.46410 –106.25901 3077.83 3077.51 0.32 0.32
WY–MB568 41.45625 –106.27278 41.45626 –106.27279 3073.55 3073.28 0.28 0.28
WY–MB569 41.47083 –106.28379 41.47083 –106.28379 3055.43 3055.10 0.33 0.33
WY–MB570 41.48219 –106.29583 41.48219 –106.29583 3035.92 3035.62 0.30 0.30
WY–MB571 41.48175 –106.26286 41.48175 –106.26286 3049.84 3049.53 0.31 0.31
WY–MB572 41.48593 –106.27830 41.48593 –106.27829 2946.91 2943.84 3.07 3.07
WY–MB573 41.49861 –106.28389 41.49859 –106.28388 2940.61 2940.15 0.46 0.46
WY–MB574 41.35981 –106.18889 41.35980 –106.18890 2905.54 2905.28 0.26 0.26
WY–MB575 41.37285 –106.20701 41.37284 –106.20703 3062.39 3062.32 0.06 0.06
WY–MB576 41.34232 –106.18478 41.34233 –106.18479 2782.28 2782.24 0.04 0.04
WY–MB577 41.32670 –106.18456 41.32671 –106.18457 2715.24 2715.07 0.17 0.17
WY–MB578 41.34118 –106.20559 41.34119 –106.20560 2889.53 2889.33 0.19 0.19
WY–MB579 41.34941 –106.21585 41.34942 –106.21586 2987.38 2987.24 0.14 0.14
WY–MB580 41.37390 –106.24701 41.37391 –106.24702 3225.84 3225.55 0.28 0.28
WY–MB581 41.35780 –106.23310 41.35781 –106.23311 3095.83 3095.61 0.21 0.21
WY–MB582 41.35124 –106.25958 41.35124 –106.25958 3194.78 3194.64 0.15 0.15
WY–MB583 41.35149 –106.28097 41.35150 –106.28097 3232.63 3232.42 0.21 0.21
WY–MB584 41.36052 –106.26446 41.36051 –106.26446 3218.29 3218.16 0.14 0.14
WY–MB585 41.35868 –106.29448 41.35868 –106.29448 3284.27 3283.91 0.36 0.36
WY–MB586 41.34155 –106.30579 41.34154 –106.30579 3297.49 3297.19 0.30 0.30
WY–MB587 41.33727 –106.32016 41.33726 –106.32014 3217.13 3216.98 0.15 0.15
WY–MB588 41.31288 –106.35900 41.31287 –106.35901 3193.29 3193.05 0.24 0.24
WY–MB589 41.32837 –106.36387 41.32837 –106.36388 3101.15 3100.74 0.40 0.40
WY–MB590 41.31746 –106.34631 41.31745 –106.34631 3237.34 3237.02 0.32 0.32
WY–MB591 41.34466 –106.37755 41.34466 –106.37756 2967.09 2966.92 0.17 0.17
WY–MB592 41.36871 –106.37738 41.36872 –106.37738 3165.50 3165.29 0.21 0.21
WY–MB593 41.35236 –106.38354 41.35238 –106.38354 3051.39 3051.08 0.31 0.31
WY–MB594 41.35572 –106.39594 41.35571 –106.39594 3062.38 3062.04 0.35 0.35
WY–MB595 41.34407 –106.39819 41.34405 –106.39819 2891.16 2890.84 0.32 0.32
WY–MB596 41.33876 –106.41694 41.33875 –106.41695 2813.67 2813.49 0.18 0.18
WY–MB597 41.33429 –106.43329 41.33428 –106.43327 2760.35 2759.99 0.37 0.37
WY–MB598 41.33547 –106.44952 41.33545 –106.44952 2710.88 2710.85 0.03 0.03
WY–MB599 41.33790 –106.46655 41.33789 –106.46655 2655.43 2655.29 0.14 0.14
WY–MB600 41.33987 –106.48643 41.33986 –106.48643 2594.88 2593.65 1.23 1.23
WY–MB601 41.34448 –106.50441 41.34447 –106.50442 2532.86 2532.66 0.20 0.20
WY–MB602 41.34786 –106.52291 41.34786 –106.52291 2473.84 2473.60 0.24 0.24
WY–MB603 41.33354 –106.51849 41.33353 –106.51850 2501.09 2500.91 0.18 0.18
WY–MB604 41.32386 –106.50193 41.32386 –106.50194 2542.62 2542.48 0.13 0.13
WY–MB605 41.32934 –106.47678 41.32934 –106.47679 2651.04 2651.03 0.01 0.01
WY–MB606 41.32362 –106.45199 41.32361 –106.45200 2795.31 2795.19 0.11 0.11
WY–MB607 41.32444 –106.42427 41.32445 –106.42427 2924.09 2923.92 0.17 0.17
WY–MB608 41.34529 –106.36044 41.34529 –106.36044 3139.11 3138.94 0.17 0.17
WY–MB609 41.32228 –106.38720 41.32226 –106.38721 3002.52 3002.33 0.20 0.20
WY–MB610 41.32165 –106.40788 41.32164 –106.40789 2963.94 2963.83 0.12 0.12
WY–MB611 41.30854 –106.38885 41.30853 –106.38886 3091.15 3090.82 0.33 0.33
WY–MB612 41.29757 –106.38299 41.29756 –106.38301 3145.04 3144.82 0.23 0.23
WY–MB613 41.28690 –106.37650 41.28688 –106.37651 3101.85 3101.70 0.15 0.15
WY–MB614 41.28625 –106.36023 41.28622 –106.36024 3000.34 3000.32 0.02 0.02
WY–MB615 41.29944 –106.35908 41.29941 –106.35908 3041.05 3040.98 0.07 0.07
WY–MB616 41.31065 –106.43329 41.31064 –106.43329 2844.89 2844.62 0.27 0.27
WY–MB617 41.30018 –106.44522 41.30019 –106.44522 2758.25 2757.99 0.26 0.26
WY–MB618 41.28856 –106.45303 41.28856 –106.45302 2683.76 2683.56 0.20 0.20
WY–MB619 41.27598 –106.45759 41.27598 –106.45759 2639.70 2639.35 0.36 0.36
WY–MB620 41.26670 –106.46745 41.26671 –106.46746 2645.14 2645.02 0.12 0.12
WY–MB621 41.26679 –106.44476 41.26681 –106.44476 2736.19 2735.88 0.31 0.31
WY–MB622 41.27006 –106.43131 41.27006 –106.43133 2882.87 2882.68 0.19 0.19
WY–MB623 41.27354 –106.41756 41.27355 –106.41759 2952.08 2951.80 0.28 0.28
WY–MB624 41.27963 –106.40188 41.27964 –106.40189 3063.82 3063.56 0.26 0.26
WY–MB625 41.28087 –106.39031 41.28089 –106.39033 2996.80 2996.54 0.27 0.27
WY–MB626 41.26106 –106.45549 41.26107 –106.45551 2661.72 2661.57 0.14 0.14
WY–MB627 41.24914 –106.46006 41.24914 –106.46008 2630.29 2630.16 0.13 0.13
WY–MB628 41.25510 –106.44214 41.25509 –106.44216 2607.63 2607.44 0.19 0.19
WY–MB629 41.25491 –106.42496 41.25491 –106.42498 2589.58 2589.53 0.05 0.05
WY–MB630 41.26188 –106.40894 41.26187 –106.40896 2607.66 2607.64 0.02 0.02
WY–MB631 41.26583 –106.39063 41.26583 –106.39064 2630.06 2630.01 0.05 0.05
WY–MB632 41.27255 –106.37663 41.27255 –106.37665 2654.22 2654.14 0.08 0.08
WY–MB633 41.27468 –106.35713 41.27467 –106.35714 2709.69 2709.54 0.15 0.15
WY–MB634 41.28110 –106.34158 41.28111 –106.34158 2786.58 2786.38 0.20 0.20
WY–MB635 41.28853 –106.32510 41.28853 –106.32510 2869.34 2869.14 0.20 0.20
WY–MB636 41.29911 –106.31249 41.29912 –106.31250 2944.56 2944.28 0.28 0.28
WY–MB637 41.28596 –106.47379 41.28599 –106.47380 2667.80 2667.65 0.15 0.15
WY–MB638 41.29813 –106.46541 41.29815 –106.46541 2713.53 2712.81 0.72 0.72
WY–MB639 41.30993 –106.45597 41.30994 –106.45597 2781.09 2780.78 0.31 0.31
Table 5.    Location information for the 139 gravity stations located on the Medicine Bow Mountains of Wyoming (WY–MB) from Brown and others (2025).

Table 6.    

Location information for the 59 gravity stations located on the Wet Mountains of Colorado (CO–WM) from Magnin and Anderson (2024).

[“Gravity station” refers to a unique identifier that is based on the station number used in the data source for this table. “UC LAT” and “UC LON” refer to the horizontal coordinates before differential correction. “DC LAT” and “DC LON” refer to the differentially corrected horizontal coordinates. “DGNSS ELEV” refers to the elevation data from the differential global navigation satellite system (dGNSS) equipment from the differentially corrected coordinates. “LIDAR ELEV” refers to the light detection and ranging (lidar) derived elevation from the 1-meter (m) digital elevation model (DEM). “ELEV DIFF” refers to the elevation difference (dGNSS – lidar), and “ABS ELEV DIFF” refers to the absolute value of this difference. NAD 83, North American Datum of 1983; NAVD 88, North American Vertical Datum of 1988]
Gravity station UC LAT
(NAD 83)		 UC LON
(NAD 83)		 DC LAT
(NAD 83)		 DC LON
(NAD 83)		 DGNSS
ELEV (m)
(NAVD 88)		 LIDAR
ELEV (m)
(NAVD 88)		 ELEV
DIFF
(m)		 ABS ELEV
DIFF
(m)
CO–WM300 38.31006 –105.35527 38.31004 –105.35526 2101.07 2100.79 0.28 0.28
CO–WM301 38.29837 –105.35721 38.29836 –105.35720 2121.65 2121.24 0.41 0.41
CO–WM302 38.29417 –105.35912 38.29414 –105.35911 2129.39 2129.27 0.12 0.12
CO–WM303 38.28391 –105.35495 38.28388 –105.35494 2148.09 2147.80 0.29 0.29
CO–WM304 38.27815 –105.35453 38.27814 –105.35454 2161.73 2161.46 0.27 0.27
CO–WM305 38.26982 –105.35141 38.26981 –105.35141 2179.96 2179.67 0.29 0.29
CO–WM306 38.26719 –105.35480 38.26718 –105.35478 2190.84 2190.52 0.31 0.31
CO–WM307 38.26307 –105.35934 38.26307 –105.35934 2201.92 2201.58 0.34 0.34
CO–WM308 38.26102 –105.36307 38.26101 –105.36307 2205.89 2205.52 0.37 0.37
CO–WM309 38.25873 –105.37197 38.25871 –105.37198 2216.51 2216.19 0.32 0.32
CO–WM310 38.25520 –105.37646 38.25519 –105.37647 2225.66 2225.29 0.37 0.37
CO–WM311 38.24934 –105.38073 38.24933 –105.38074 2234.73 2235.09 –0.36 0.36
CO–WM312 38.24533 –105.38533 38.24530 –105.38534 2243.33 2243.24 0.09 0.09
CO–WM313 38.23901 –105.38846 38.23899 –105.38848 2251.57 2251.65 –0.08 0.08
CO–WM314 38.23475 –105.38846 38.23472 –105.38848 2255.81 2255.86 –0.05 0.05
CO–WM315 38.23029 –105.39197 38.23027 –105.39198 2268.27 2268.04 0.23 0.23
CO–WM316 38.22717 –105.39525 38.22715 –105.39526 2274.55 2274.18 0.37 0.37
CO–WM317 38.22334 –105.40223 38.22333 –105.40227 2283.91 2284.06 –0.15 0.15
CO–WM318 38.23332 –105.40288 38.23332 –105.40289 2408.71 2408.94 –0.23 0.23
CO–WM319 38.24616 –105.39248 38.24616 –105.39249 2265.00 2264.96 0.04 0.04
CO–WM320 38.25602 –105.38334 38.25603 –105.38334 2280.00 2279.92 0.08 0.08
CO–WM321 38.25907 –105.39394 38.25907 –105.39394 2395.34 2395.25 0.09 0.09
CO–WM322 38.26950 –105.38806 38.26949 –105.38806 2398.60 2398.58 0.02 0.02
CO–WM323 38.27286 –105.39011 38.27285 –105.39010 2366.05 2366.03 0.02 0.02
CO–WM324 38.28735 –105.40667 38.28734 –105.40668 2274.35 2274.34 0.01 0.01
CO–WM325 38.29275 –105.39243 38.29273 –105.39243 2380.41 2380.41 0.00 0.00
CO–WM326 38.28718 –105.38645 38.28716 –105.38644 2326.71 2326.70 0.01 0.01
CO–WM327 38.28938 –105.37284 38.28937 –105.37284 2224.21 2224.36 –0.15 0.15
CO–WM328 38.26465 –105.37548 38.26464 –105.37548 2345.54 2345.57 –0.03 0.03
CO–WM329 38.25471 –105.36188 38.25469 –105.36189 2257.82 2257.71 0.11 0.11
CO–WM330 38.24246 –105.37071 38.24243 –105.37072 2302.59 2302.50 0.09 0.09
CO–WM331 38.24149 –105.37685 38.24148 –105.37686 2271.77 2271.80 –0.03 0.03
CO–WM332 38.11421 –105.18721 38.11420 –105.18722 2861.52 2861.53 –0.01 0.01
CO–WM333 38.11834 –105.19500 38.11833 –105.19501 2844.62 2844.62 0.00 0.00
CO–WM334 38.11539 –105.20536 38.11538 –105.20537 2851.18 2851.05 0.13 0.13
CO–WM335 38.09331 –105.21065 38.09329 –105.21067 3263.29 3262.77 0.52 0.52
CO–WM336 38.09336 –105.17546 38.09335 –105.17546 2882.04 2881.89 0.15 0.15
CO–WM337 38.09126 –105.17045 38.09125 –105.17046 2955.79 2956.01 –0.22 0.22
CO–WM338 38.08223 –105.15881 38.08223 –105.15881 3160.31 3160.21 0.10 0.10
CO–WM339 38.07603 –105.16797 38.07602 –105.16798 3161.92 3161.82 0.10 0.10
CO–WM340 38.07120 –105.17146 38.07119 –105.17146 3105.18 3105.85 –0.67 0.67
CO–WM341 38.06252 –105.18589 38.06251 –105.18590 3159.78 3159.74 0.04 0.04
CO–WM342 38.07947 –105.18030 38.07944 –105.18029 2925.35 2921.68 3.67 3.67
CO–WM343 38.09203 –105.14929 38.09200 –105.14930 2941.98 2941.82 0.16 0.16
CO–WM344 38.08606 –105.13990 38.08604 –105.13992 2934.02 2934.11 –0.09 0.09
CO–WM345 38.06968 –105.22355 38.06966 –105.22357 3171.49 3171.41 0.08 0.08
CO–WM346 38.07352 –105.22973 38.07349 –105.22974 3189.36 3189.64 –0.28 0.28
CO–WM347 38.07574 –105.24332 38.07573 –105.24332 3115.80 3115.97 –0.17 0.17
CO–WM348 38.06952 –105.23591 38.06952 –105.23593 3068.66 3068.71 –0.05 0.05
CO–WM349 38.06894 –105.22953 38.06894 –105.22955 3119.76 3119.79 –0.03 0.03
CO–WM350 38.07174 –105.23154 38.07174 –105.23155 3142.02 3141.75 0.27 0.27
CO–WM351 38.08607 –105.24776 38.08608 –105.24777 3170.15 3169.97 0.18 0.18
CO–WM352 38.08224 –105.24561 38.08225 –105.24560 3140.92 3140.93 –0.01 0.01
CO–WM353 38.08720 –105.22464 38.08718 –105.22464 3220.52 3220.55 –0.03 0.03
CO–WM354 38.09102 –105.22718 38.09100 –105.22718 3260.35 3260.33 0.02 0.02
CO–WM355 38.09067 –105.23085 38.09065 –105.23085 3287.47 3288.41 –0.94 0.94
CO–WM356 38.08886 –105.23514 38.08884 –105.23515 3280.50 3280.75 –0.25 0.25
CO–WM357 38.08606 –105.23944 38.08604 –105.23944 3224.57 3224.24 0.33 0.33
CO–WM358 38.09156 –105.23900 38.09156 –105.23900 3313.85 3313.63 0.22 0.22
Table 6.    Location information for the 59 gravity stations located on the Wet Mountains of Colorado (CO–WM) from Magnin and Anderson (2024).

Table 7.    

Location information for the 56 gravity stations located on the Keweenaw Peninsula of Michigan (MI–KP0) from Murchek and others (2025).

[“Gravity station” refers to a unique identifier that is based on the station number used in the data source for this table. “UC LAT” and “UC LON” refer to the horizontal coordinates before differential correction. “DC LAT” and “DC LON” refer to the differentially corrected horizontal coordinates. “DGNSS ELEV” refers to the elevation data from the differential global navigation satellite system (dGNSS) equipment from the differentially corrected coordinates. “LIDAR ELEV” refers to the light detection and ranging (lidar) derived elevation from the 1-meter (m) digital elevation model (DEM). “ELEV DIFF” refers to the elevation difference (dGNSS – lidar), and “ABS ELEV DIFF” refers to the absolute value of this difference. NAD 83, North American Datum of 1983; NAVD 88, North American Vertical Datum of 1988]
Gravity station UC LAT
(NAD 83)		 UC LON
(NAD 83)		 DC LAT
(NAD 83)		 DC LON
(NAD 83)		 DGNSS
ELEV (m)
(NAVD 88)		 LIDAR
ELEV (m)
(NAVD 88)		 ELEV
DIFF
(m)		 ABS ELEV
DIFF
(m)
MI–KP0–1 47.19247 –88.48937 47.19248 –88.48937 357.97 357.83 0.14 0.14
MI–KP0–2 47.2386 –88.61182 47.2386 –88.61181 186.12 185.82 0.31 0.31
MI–KP0–3 47.23998 –88.59468 47.23998 –88.59468 189.02 188.48 0.53 0.53
MI–KP0–4 47.22843 –88.59448 47.22843 –88.59447 198.65 198.31 0.34 0.34
MI–KP0–5 47.23928 –88.59002 47.23927 –88.59001 194.57 194.42 0.15 0.15
MI–KP0–6 47.22849 –88.58479 47.22849 –88.58478 207.38 206.85 0.52 0.52
MI–KP0–7 47.22858 –88.57424 47.22857 –88.57423 221.14 220.83 0.31 0.31
MI–KP0–8 47.23942 –88.57388 47.23942 –88.57387 193.96 193.64 0.32 0.32
MI–KP0–9 47.21424 –88.56344 47.21424 –88.56344 283.33 283.08 0.24 0.24
MI–KP0–10 47.18516 –88.56329 47.18514 –88.56329 318.8 318.72 0.07 0.07
MI–KP0–11 47.21431 –88.55265 47.21431 –88.55265 300.8 300.71 0.09 0.09
MI–KP0–12 47.2138 –88.54236 47.21379 –88.54235 323.6 323.45 0.15 0.15
MI–KP0–13 47.18488 –88.53965 47.18487 –88.53965 333.12 333.07 0.05 0.05
MI–KP0–14 47.21352 –88.53145 47.21351 –88.53145 327.83 327.78 0.05 0.05
MI–KP0–15 47.2067 –88.52091 47.2067 –88.52091 351.73 351.52 0.21 0.21
MI–KP0–16 47.21363 –88.52081 47.21362 –88.52080 351.01 350.86 0.14 0.14
MI–KP0–17 47.17455 –88.51855 47.17455 –88.51855 333.56 333.58 –0.02 0.02
MI–KP0–18 47.20738 –88.50895 47.20738 –88.50894 360.93 360.62 0.3 0.3
MI–KP0–19 47.19935 –88.49976 47.19935 –88.49976 359.46 359.34 0.12 0.12
MI–KP0–20 47.19036 –88.49965 47.19035 –88.49964 353.43 353.33 0.11 0.11
MI–KP0–21 47.19392 –88.49585 47.19391 –88.49584 356.93 356.81 0.13 0.13
MI–KP0–22 47.18917 –88.49367 47.18916 –88.49366 357.74 357.75 –0.01 0.01
MI–KP0–23 47.13179 –88.48612 47.13179 –88.48611 190.49 190.48 0.01 0.01
MI–KP0–24 47.18894 –88.48568 47.18893 –88.48569 365.34 365.31 0.03 0.03
MI–KP0–25 47.19946 –88.48134 47.19945 –88.48133 359.63 359.64 –0.01 0.01
MI–KP0–26 47.18842 –88.47950 47.18843 –88.47950 354.53 354.47 0.06 0.06
MI–KP0–27 47.14506 –88.47867 47.14505 –88.47866 269.47 269.54 –0.07 0.07
MI–KP0–28 47.1853 –88.47486 47.1853 –88.47485 354.27 354.18 0.09 0.09
MI–KP0–29 47.18223 –88.47155 47.18223 –88.47155 337.38 337.18 0.2 0.2
MI–KP0–30 47.20707 –88.47135 47.20707 –88.47134 365.23 365.08 0.16 0.16
MI–KP0–31 47.17804 –88.46743 47.17804 –88.46742 324.81 324.66 0.15 0.15
MI–KP0–32 47.17419 –88.46209 47.17417 –88.46208 314.46 313.5 0.96 0.96
MI–KP0–33 47.14882 –88.45806 47.14882 –88.45805 190.87 190.83 0.04 0.04
MI–KP0–34 47.1709 –88.45737 47.1709 –88.45735 306.2 305.98 0.23 0.23
MI–KP0–35 47.1674 –88.45202 47.16739 –88.45201 273.23 273.09 0.14 0.14
MI–KP0–36 47.20788 –88.44713 47.20787 –88.44713 356.72 356.54 0.18 0.18
MI–KP0–37 47.18497 –88.44653 47.18497 –88.44652 311.7 311.74 –0.04 0.04
MI–KP0–38 47.19592 –88.44639 47.19592 –88.44638 337 337.07 –0.07 0.07
MI–KP0–39 47.16467 –88.44616 47.16467 –88.44616 226.5 226.36 0.14 0.14
MI–KP0–40 47.17307 –88.44471 47.17307 –88.44472 267.49 267.5 –0.02 0.02
MI–KP0–41 47.16355 –88.43915 47.16355 –88.43915 187.27 187.07 0.2 0.2
MI–KP0–42 47.16107 –88.43507 47.16106 –88.43507 184.11 184.01 0.09 0.09
MI–KP0–43 47.15894 –88.43253 47.15893 –88.43253 184.07 183.39 0.68 0.68
MI–KP0–44 47.15447 –88.42535 47.15447 –88.42535 198.16 197.89 0.27 0.27
MI–KP0–45 47.14855 –88.42529 47.14855 –88.42530 216.99 214.63 2.36 2.36
MI–KP0–46 47.14989 –88.41428 47.14988 –88.41427 185.32 185.14 0.18 0.18
MI–KP0–47 47.14911 –88.39405 47.14911 –88.39405 196.15 195.98 0.17 0.17
MI–KP0–48 47.17075 –88.38358 47.17075 –88.38358 226.35 226.3 0.05 0.05
MI–KP0–49 47.14186 –88.38341 47.14186 –88.38341 218.89 218.71 0.19 0.19
MI–KP0–50 47.12744 –88.36215 47.12744 –88.36215 221.22 221 0.22 0.22
MI–KP0–51 47.11808 –88.34597 47.11808 –88.34597 202.97 202.92 0.05 0.05
MI–KP0–52 47.1147 –88.34358 47.11471 –88.34357 195.46 194.97 0.49 0.49
MI–KP0–53 47.17086 –88.34093 47.17086 –88.34092 226.63 226.62 0.01 0.01
MI–KP0–54 47.13504 –88.29974 47.13504 –88.29974 192.78 192.76 0.02 0.02
MI–KP0–55 47.12553 –88.29006 47.12553 –88.29006 189.78 187.11 2.67 2.67
1MI–KP0–M65 47.2436 –88.44747 47.2436 –88.44747 380.18 379.69 0.49 0.49
Table 7.    Location information for the 56 gravity stations located on the Keweenaw Peninsula of Michigan (MI–KP0) from Murchek and others (2025).
1

The data for this National Geodetic Survey (NGS) station are from NGS (2025). This gravity station identifier was created for use in this report.

References Cited

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Conversion Factors

International System of Units to U.S. customary units

Multiply By To obtain
centimeter (cm) 0.3937 inch (in.)
meter (m) 3.281 foot (ft)
kilometer (km) 0.6214 mile (mi)
meter (m) 1.094 yard (yd)
square meter (m2) 10.76 square foot (ft2)
square kilometer (km2) 0.3861 square mile (mi2)

Datums

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 (NAVD 88).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Elevation, as used in this report, refers to distance above the vertical datum.

Abbreviations

3DEP

3D Elevation Program

ASPRS

American Society for Photogrammetry and Remote Sensing

cm

centimeter

CO–WM

Wet Mountains of Colorado

DEM

digital elevation model

dGNSS

differential global navigational satellite system

GLONASS

Globalnaya Navigazionnaya Sputnikovaya Sistema [Global Navigation Satellite System]

GNSS

global navigation satellite system

GPS

Global Positioning System

IDW

inverse distance weighted

IMU

inertial measurement unit

km

kilometer

km2

square kilometer

lidar

light detection and ranging

m

meter

mGal

milligal

MI–HR

west-central Upper Peninsula of Michigan

MI–KP0

Keweenaw Peninsula of Michigan

MI–TM

central Upper Peninsula of Michigan

NAD 83

North American Datum of 1983

NAVD 88

North American Vertical Datum of 1988

NGS

National Geodetic Survey

NOAA

National Oceanic and Atmospheric Administration

NPD

nominal pulse density

NPS

nominal pulse spacing

QL

quality level

RMSEz

root mean square error in the vertical (z) direction

TIN

triangulated irregular network

UP

upper peninsula

USGS

U.S. Geological Survey

WY–MB

Medicine Bow Mountains of Wyoming

 
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Suggested Citation

Murchek, J.T., Drenth, B.J., Reitman, J.J., Anderson, E.D., Magnin, B.P., and DeGraff, J.M., 2025, The feasibility of using lidar-derived digital elevation models for gravity data reduction (ver. 1.1, July 2025): U.S. Geological Survey Open-File Report 2025–1019, 33 p., https://doi.org/10.3133/ofr20251019.

ISSN: 2331-1258 (online)

Publication type Report
Publication Subtype USGS Numbered Series
Title The feasibility of using lidar-derived digital elevation models for gravity data reduction
Series title Open-File Report
Series number 2025-1019
DOI 10.3133/ofr20251019
Edition Version 1.0: May 12, 2025; Version 1.1: July 1, 2025
Publication Date May 12, 2025
Year Published 2025
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center
Description vii, 33 p.
Online Only (Y/N) Y
Additional Online Files (Y/N) N
Additional publication details