Journal of Maps ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/tjom20 Geology of the Hokusai quadrangle (H05), Mercury Jack Wright , David A. Rothery , Matthew R. Balme & Susan J. Conway To cite this article: Jack Wright , David A. Rothery , Matthew R. Balme & Susan J. Conway (2019) Geology of the Hokusai quadrangle (H05), Mercury, Journal of Maps, 15:2, 509-520, DOI: 10.1080/17445647.2019.1625821 To link to this article: https://doi.org/10.1080/17445647.2019.1625821 © 2019 The Author(s). Published by Informa View supplementary material UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps Published online: 17 Jun 2019. Submit your article to this journal Article views: 1190 View related articles View Crossmark data Citing articles: 8 View citing articles Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tjom20 JOURNAL OF MAPS 2019, VOL. 15, NO. 2, 509–520 https://doi.org/10.1080/17445647.2019.1625821 Science Geology of the Hokusai quadrangle (H05), Mercury Jack Wright a, David A. Rothery a, Matthew R. Balme a and Susan J. Conway b aSchool of Physical Sciences, The Open University, Milton Keynes, UK; bCNRS UMR 6112, Laboratoire de Planétologie et Géodynamique, Université de Nantes, Nantes, France ABSTRACT ARTICLE HISTORY The Hokusai (H05) quadrangle is in Mercury’s northern mid-latitudes (0–90°E, 22.5–65°N) and Received 22 February 2019 covers almost 5 million km2, or 6.5%, of the planet’s surface. We have used data from the Revised 23 May 2019 MESSENGER spacecraft to make the first geological map of H05. Linework was digitized at Accepted 24 May 2019 fi ∼ 1:400,000-scale for nal presentation at 1:3,000,000-scale, mainly using a 166 m/pixel KEYWORDS monochrome basemap. Three major photogeologic units of regional extent were mapped: ≥ Mercury; planetary geology; intercrater, intermediate, and smooth plains. Materials of craters 20 km in diameter were Hokusai; quadrangle; impact classified according to their degradation state. Two classification schemes were employed in craters; planetary volcanism parallel, one with three classes and the other with five classes, for compatibility with existing MESSENGER-era quadrangle maps and the first global geologic map. This map will provide science context and targets for the ESA-JAXA BepiColombo mission to Mercury. 1. Introduction 2. Data To date, Mercury has been the focus of two spacecraft 2.1. Basemaps missions: Mariner 10 (1974–1975; Dunne & Burgess, 1978) and MErcury, Surface, Space ENvironment, 2.1.1. Monochrome GEochemistry, and Ranging (MESSENGER; 2008– The primary data for planetary photogeological map- 2015; Solomon, Nittler, & Anderson, 2018). Mercury ping are monochrome image mosaic basemaps. MES- has 15 latitudinally- and longitudinally-defined map- SENGER’s Mercury Dual Imaging System (MDIS; ping quadrangles (Figure 1(b)). Following Mariner Hawkins et al., 2007) collected image data with its 10’s flybys, 1:5,000,000 (1:5M) scale geological maps monochrome narrow-angle camera and multispectral were made of the Borealis (H01; Grolier & Boyce, wide-angle camera. With these, Chabot et al. (2016) 1984), Victoria (H02; McGill & King, 1983), Shakes- created basemap mosaics with different illumination peare (H03; Guest & Greeley, 1983), Kuiper (H06; conditions covering the whole planet. The main base- DeHon, Scott, & Underwood, 1981), Beethoven maps we used to map H05 were its four version 0 (H07; King & Scott, 1990), Tolstoj (H08; Schaber & ∼166 m/pixel map-projected Basemap Reduced Data McCauley, 1980), Discovery (H11; Trask & Dzurisin, Record (BDR) tiles (Figure 1(a)), which are consist- 1984), Michaelangelo (H12; Spudis & Prosser, 1984), ent with the basemaps of the other published MES- and Bach (H15; Strom, Malin, & Leake, 1990) quad- SENGER-era quadrangle maps (Galluzzi et al., 2016; rangles. Hokusai (H05; 0–90°E, 22.5–65°N) was not Guzzetta et al., 2017; Mancinelli et al., 2016). These mapped, as it was unimaged (Davies, Dornik, Gault, tiles have moderate solar incidence angles (∼68°; & Strom, 1978). Chabot et al., 2016). Auxiliary basemaps for H05 MESSENGER was the first spacecraft to image Mer- with low incidence angles, for investigating surface cury entirely (Solomon et al., 2018). This allowed the reflectance variations (Figure 1(c)), and high inci- first global geological map of Mercury to be produced dence angles, with both western and eastern illumi- (1:15M-scale; Kinczyk et al., 2018). MESSENGER nation, for enhancing subtle topographic features data resolution is sufficient for larger-scale (1:3M) (Figure 1(d) and (e)), became available early during quadrangle maps to be made. So far, H02 (Galluzzi mapping (Chabot et al., 2016). Final, version 2, con- et al., 2016), H03 (Guzzetta, Galluzzi, Ferranti, & trolled basemaps for H05 were released after map- Palumbo, 2017), and H04 (Mancinelli, Minelli, ping was substantially underway (Denevi et al., Pauselli, & Federico, 2016) have been published. 2018). Subsequent Mercury quadrangle maps are Here, we present the first geological map of H05 being constructed using these basemaps (Galluzzi (Main Map), which we began in October 2015. et al., 2019). CONTACT Jack Wright [email protected] School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK This article has been republished with minor changes. These changes do not impact the academic content of the article © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 510 J. WRIGHT ET AL. Figure 1. H05 basemaps. (a) Mosaic of the ∼166 m/pixel MDIS BDR basemap tiles. (b) ∼665 m/pixel global MDIS enhanced color mosaic (cylindrical projection; Denevi et al., 2016). Quadrangles are labeled and outlined. (c) Mosaic of the ∼166 m/pixel low-inci- dence angle basemap tiles. (d) Mosaic of the ∼166 m/pixel high-incidence angle (western) basemap tiles. (e) Mosaic of the high- incidence angle (eastern) basemap tiles. Panels (a) and (c–e) show H05’s native Lambert Conformal Conic projection (central mer- idian, 45°E; standard parallels, 30°N and 58°N). Monochrome products are by Chabot et al. (2016). 2.1.1.1. Color. Geomorphic units can sometimes be 2.1.2. Topography distinguished by color. We used the MESSENGER We used topographic data to aid mapping. Mercury ∼665 m/pixel global enhanced color mosaic to Laser Altimeter (MLA; Cavanaugh et al., 2007)data inform our photogeological interpretations (Figure created a digital elevation model (DEM) of Mercury’s 1(b); Denevi et al., 2016). This was constructed northern hemisphere, encompassing H05 (Figure 2(a); using MDIS frames captured in the 430, 750, and ∼665 m/pixel; Zuber et al., 2012). MLA tracks diverge 1000 nm bands. Principal component analyses were from the north, which means that this DEM suffers conducted by the MESSENGER team in this spectral from interpolation uncertainties in southern H05. Shortly space and they created the enhanced color mosaic after mapping began, the first global stereo-DEM of by placing the second principal component, first Mercury was released (Figure 2(b); ∼665 m/pixel; principal component, and the 430/1000 ratio in Becker et al., 2016), which mitigated MLA DEM uncer- the red, green, and blue channels, respectively tainties. Later, an improved stereo-DEM of H05 was (Denevi et al., 2009, 2016). released with higher spatial resolution (Figure 2(c); JOURNAL OF MAPS 511 Figure 2. Topographic data for H05. Each panel (a–c) shows a quadrangle view (left) with a box indicating the location of the enlarged example (right). All panels show H05’s native Lambert Conformal Conic projection. (a) ∼665 m/pixel gridded MLA DEM (Zuber et al., 2012). (b) ∼665 m/pixel stereo-DEM (Becker et al., 2016). (c) ∼222 m/pixel stereo-DEM (Stark et al., 2017). ∼222 m/pixel; Stark et al., 2017). This became the primary geological maps (Galluzzi et al., 2016; Guzzetta et al., source of topographic information for H05. 2017; Mancinelli et al., 2016). USGS guidance for pla- netary mappers recommends that digitization should ∼ 3. Methods be conducted at a scale 4× the publication scale (Skin- ner et al., 2018). Thus, a map to be published at 1:3M- 3.1. Projection scale should be digitized at ∼1:750k-scale. An alterna- H05, centered on 45°E, lies in Mercury’s northern mid- tive recommendation is that the digitization scale latitudes (Figure 1(b)). MESSENGER-era geological should be 2,000× the basemap raster resolution maps of the other quadrangles in this band were cre- (Tobler, 1987). Thus, the recommended digitization ∼ ated in Lambert Conformal Conic (LCC) projections scale would be 1:300k, because the basemap resol- ∼ (standard parallels 30°N and 58°N; Galluzzi et al., ution is 166 m/pixel. Cognizant of these constraints, 2016; Guzzetta et al., 2017; Mancinelli et al., 2016). we digitized H05 at a scale of 1:400k. We mapped H05 in a LCC projection with identical standard parallels to facilitate future fusion of these 3.3. Digitization strategy maps (Figure 1(a); Galluzzi et al., 2019). The reference datum for this projected coordinate system is a sphere We digitized vector layers on the basemap raster layers of radius 2,440 km; the published shape of Mercury in Esri ArcMap 10.1 Geographic Information System when mapping began (Mazarico et al., 2014). We software. Primary digitizations belong to one of three used the United States Geological Survey (USGS) Inte- feature classes: (1) geological contacts (polylines); (2) grated Software for Imagers and Spectrometers version linear features (polylines), and; (3) surface features 3 (ISIS3) to reproject the raw basemaps.