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Earth and Planetary Science Letters

Supporting Information for

Using satellite imagery to identify and analyze tumuli on Earth and Mars

Serina Diniega*,a

Simran Sanghab

Brandon Brownec

aJet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 321-630,

Pasadena, CA 91109, USA (818-393-1487, serina.diniega@jpl.nasa.gov)

bUCLA, Los Angeles, CA, USA; previously at Occidental College, Eagle Rock, CA, USA

cHumboldt State University, Arcata, CA, USA; previously at Occidental College

*Corresponding Author

© 2016. All rights reserved.

Contents of this file

Figures S1 to S9

Introduction

These figures provide more information about the methodology for remote survey, identification, and measurement of tumuli on planetary lava flows (S1, S7) – and its limitations (S2, S8). Also, more information is provided about the study sites (S3-S6), and a field-by-field look at individual tumulus’ shape and size (S9).

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Figure S1. The lava flow inflation feature identification flowchart, used in all surveys to identify tumuli and other lava flow features.

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Figure S2. Distinctive vs. obscured clefts, within martian tumuli. Due to difficulty in finding distinctive clefts (examples are shown top images) within martian images, these features were not required for tumuli identification in this study despite its common use within terrestrial field studies. Dust cover through many of the martian fields was a major obstacle that often obscured tumuli margins (bottom right) in addition to the clefts themselves (bottom left). Shown are aerial views of several tumuli from different fields within the southern edge of Elysium Planitia, Mars.

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Lava field name Latitude, Longitude Age (years)

Number of tumuli measured

Mean Density

PKK flow Puʻu ʻŌʻō, HI, USA (1) 19.3°N, 155.1°W <10 (2004-

2007) 73 68.6 1859 Mauna Loa flow, HI, USA (2) 19.9°N, 155.9°W 154 (1859) 95 25.0

Nesjahraun flow, Iceland (3) 64.1°N, 21.2°W ~2,500 86 5.7 Hell's Half Acre lava field, ID, USA

(4) 43.5°N, 112.5°W ~5,200 92 16.6 1654 Mt. Etna flow, Italy (5) 37.8°N, 14.9°E 360 (1651-3) 903 49.1

Amboy Crater lava field, CA, USA (6) 34.5°N, 115.8°W ~10,000 920 59.0

Figure S3. The terrestrial lava fields considered in this study. The table shows the total tumuli measured in each field on Earth and lava field coordinates (top), and numbers signifying location of respective lava fields on the globe (bottom). Background map image retrieved from the Woods Hole Oceanographic Institution website, http://vishnu.whoi.edu/services/communications/oceanusmag.050826/v41n1/macdonald.html.

Figure S4. Five of the terrestrial lava flows studied, and tumuli distribution. In clockwise order from upper-left, the field sites shown are: E2, E1, E6, E4, and E3. Green dots show the locations of tumuli identified in this study. The flow margin shown in E1 for the Prince Kuhio Kalaniana’ole (PKK) flow boundary is from the United States Geological Survey. Map of flows from Pu`u `O`o: 19 December 2005. Hawaiian Volcano Observatory. Field site E5/Mt. Etna is shown in Figures 3-5 within the paper.

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Lava field name Latitude, Longitude

Age (time period)

Number of tumuli measured

Mean Density

(1) 5.7°N, 152.8°E Amazonian 1199 20.0 (2) 4.5°N, 156.0°E Amazonian 65 N/A (3) 2.2°N, 174.1°E Amazonian 434 2.4 (4) 3.3°S, 167.9°E Amazonian 550 27.5 (5) 1.5°N, 160.6°E Amazonian 12 N/A (6) 5.7°N, 169.7°E Amazonian 70 15.7 (7) 10.1°N, 157.2°E Amazonian 234 N/A

Figure S5. The martian lava fields where tumuli were identified, within this study. The table shows the total tumuli measured in each field within the Elysium Planitia region in Mars and lava field coordinates (top), and numbers signifying location of respective lava fields (bottom).

Figure S6. Six of the martian lava flows studied, and tumuli distribution. As in S4, green dots show the locations of tumuli identified in this study. Field site M3 is shown in Figures 3-5 with in the paper.

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Figure S6 (2 pages). Six of the martian lava flows studied, and tumuli distribution. Green dots show the locations of tumuli identified in this study. All HiRISE images are ~6km wide. Field M3 is shown in Figures 3-4 within the paper.

Figure S7. Measuring a tumulus via remote survey. After locating a cluster of tumuli (usually found in chains as above), we isolate each tumulus and measure its length, width, and long axis orientation with respect to vertical. This tumulus is also shown in Figure 1.

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Figure S8. Tumuli missed during initial remote survey of Amboy Crater lava field: The inset shows some tumuli (red crosses) found first through fieldwork – these were missed during the remote survey as they were within the shadow of the nearby steep cinder cone, yielding poor image contrast. All tumuli initially surveyed remotely are shown in the background image (yellow crosses).

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Figure S9. Individual plots of each studied field on Earth and Mars, of individual tumulus’ width and length. This contains the same information as Figure 2 in the paper.