Transcript Satellite Imaging Research ( Powerpoint )

Exploring the Migration of the
Roanoke Colonists
By: Ronesha Lucas, Eunice Smith, and Malcom B. Mathis II
Mentors: Dr. LeCompte, Dr. San Juan, Mr. Willard, Dr. Zhang and Dr. Garland
Abstract
Historical maps, archives, genealogies, and oral history indicate at least four (4) sites in North
Carolina’s Dare (2), Hyde (1) and Tyrrell (1) Counties as Native settlements. One or more of
these sites may have provided sanctuary for refugees from the ill-fated colony established on
Roanoke Island in 1587.
The archaeological research design of the Lost Colony Center for Science and Research consists
of a predictive model using traditional data but also remote sensing applications, that is, aerial,
satellite and geophysical. Environmental studies with remote sensing assist in confirming the
sites as habitable. Optical imagery and processing provided the initial results about the locales
being habitable (2003 URE Lost Colony Team).
Prior study of high-resolution satellite imagery of the Buckridge site in Tyrrell County identified
environmental characteristics conducive to habitation. The ridge vegetation of mixed trees was
distinct compared to the surrounding wetlands. However, at the highest available spatial
resolution (1m) the vegetative canopy obscured the ground at these sites. This study also did not
address other factors related to habitation.
The current study correlates remote sensing imagery with historical geospatial information to
evaluate the suitability for settlement at three locales. For this study, settlement suitability is
based upon observable, interdependent, quantifiable environmental factors governing habitability
(settlement size and area), arability (soils and vegetation) and defensibility (geographical location
and elevation). To determine these factors, data from satellite based Optical and ISAR
instruments and aerial LIDAR are compared to observe and quantify the terrain and environment
of the historical locales.
Abstract (cont’d)
Interferometric Synthetic Aperture RADAR (ISAR) data allows penetration of
obscuring vegetative canopies, although at a spatial resolution (30 m.) insufficient to
detect discrete cultural features. Light Detection and Ranging (LIDAR) data provides
adequate spatial resolution (<1 m.) but is subject to statistical uncertainties over small
areas.
For this study, ISAR data from NASA’s Shuttle RADAR Topography Mission and
LIDAR data from the North Carolina Floodplain Mapping Program were compared to
improve the site elevation accuracy. The use of new, public, environmental data sets
provided the opportunity to refine the requisite settlement characteristics of
habitability, arability and defensibility. The proximate location of sites to ECSU
yielded an opportunity to establish ground truth for measurements made remotely.
Once remote elevation and environmental data are validated, each site will be the
focus of further in- situ study to confirm settlement characteristics.
The study continues with Geophysical applications, especially Ground Penetrating
Radar, and geologic core samples at the sites with the requisite environmental and
terrain characteristics. The 2005 URE project initiated this in situ study at Croatan
(Dare) and at Goshen Ridge (Hyde).
History Behind the Mystery
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First attempt at New World
English colonization
116 Colonists landed Roanoke
Island, July 22, 1587
Elected John White Governor
Encountered hardships
John White returned to England
for assistance, August 27, 1587
“At the time of my last departure
from them, they were prepared to
remove from Roanoke 50 miles
into the main” (Miller 2000:13).
Spanish Armada delayed White’s
return until 1590
Colonists disappeared leaving
inscription “CROATOAN”
History Behind the Mystery
From Sir Walter Raleigh
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“What manner of forte I would haue I would haue It a pentangell in this
manner. With, v, large bulwarkes the Casemates of the Boulwarkes large and
open, with a way out of the bulwarke and an other Into the Streat The
Collionsides or ocrechons, large and longe, The Curtyns sumwhat slant, that
the yearthe may lye the faster and the rampir of the Curtyns very braude…”
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Paraphrased: “What manner of forte I would have I would have it pentagonal
in this manner. With five large bulwarks the casemates of the bulwarks large
and open, with a way out of the bulwark and another into the street The
collision sides or orechons, large and long, the curtains somewhat slant, that
the earth may lie that faster and the rampart of the curtains very broad…”
History Behind the Mystery
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“…hould a gaynst all the forces of Indda. How I would haue It seated,
eyther upon rocke, marrishe, an Iland or peninsula, if this forte wer In an Iland
then would I have on the next land to It a forte, wherby I would always be sure
of a landing assured, and of a retreat…”
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Paraphrased: “...hold against all the Indian forces. I would have it seated either
upon rocks, marsh, an island or peninsula, if this fort were on an island then I
would have a fort next to it whereby I would always be sure of landing assured,
and of a retreat…”
Hypothesis
• The colonists removed to sites associated with Native
American habitation and characterized by.
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Agricultural Suitability
Defensibility
Within support range of Native American allies (Croatan)
Economic Prospects
Sufficient Settlement Size
• Sites near Buxton on Cape Hatteras and near the Alligator
River headwaters may conform to colonist proposed
settlement requirements.
Approach
• Locate remnant features indicating the location
of the “Lost Colony” using an amalgam of
remote sensing data processing and GIS
techniques
– Data: Optical imagery, LIDAR, ISA-RADAR, GPR
– GIS Technology: GPS
– Archeological methodology
• Historical Map Comparison to locate known sites
• Reveal Evident Changes in Topography over 400 years
Relativity: 4 days vs 400 years
• Changes in land over the course of four days!
Archaeological Research Design
Archeology and Historic Preservation; Secretary of the Interior's Standards and
Guidelines (48 FR 44716-44742) 1983
• Phase 1 Background
Research
Includes location of historic
map-projected sites
• Previous archeological
research
• High/Low probability areas
• Conventional survey
• Phase 1 Method
– Conventional Survey
• Remote Sensing: identifies
high probability areas for
subsurface testing
• Phase 2 Evaluation Survey
• Phase 3 Data Recovery
Remote Sensing
• What is Remote Sensing?
• Sources of Remote Sensing
– Aerial
– Satellite
– In-Situ Geophysical
• Types of Remote Sensing
– Optical Multi-spectral
(IKONOS satellite)
– LIDAR (LIght Detection and
Ranging)
• NC Floodplain Mapping
Program ( NCFMP)
– ISAR (Interferometric
Synthetic Aperture Radar)
• Shuttle Radar Topography
Mission (SRTM)
– Ground Penetrating Radar
(GPR)
Kolam IKONOS University of Missouri CS
Methods
• Image Processing
– Pixoneer PG-STEAMER
• GIS Processing
– ESRI ArcMap
• Image Data Comparisons
– Satellite (IKONOS) Optical Imagery
– Satellite (SRTM) ISAR
– Aerial (NC Flood Plain Mapping
Program) LIDAR
• Map Comparisons
– Historical
– Wetland
– Soil
• In Situ Data Collection
– Ground Penetrating Radar
(GPR)
– Mapping and Surface GPS
Survey
Methods (cont’d)
• Objectives for Analysis
– Measure relative
• Distances
• Elevations
• Areas
– Geo-reference Measurements (Latitude &
Longitude)
• Vegetation classification
• Soil Classification
• Ground-truthing
Migration of the Alligator River, Croatan, and
Tramanscacooc 1585 and 1588
Migration of the Alligator River, Croatan and
Tramanscacok (Cont.)
Thoronton Morden Lea1685 and Mosley 1733
LANDSAT and Coastal Wetlands
• Hardwood Flats on
the Alligator River
• Buck and Goshen
Ridges
Soil Description for Croatan
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Carteret Sand( CeA) : located between forested
dunes in the outer banks, this location is irregular in
shape and can be used as habitat for wildlife.
Conaby Muck (CnA): surface is 14 inches thick
black in the upper part and grey in the lower, rare
flooding; soil ranges from extremely acid to strongly
acid. Area away from the salt water includes
vegetation ranging from greenbrier, eastern
baccharis, black willow, blueberry, sawgrass and
cattail. Theses varies vegetation can be used for
weaving, carving, and building houses.
Fripp Fine Sand( FrD): soil ranges from strongly
acid to mildly alkaline, seasonal high water table is
more than 6ft. below the surface. Vegetation
supports pine, live oak, cherrybark oak hickory,
black cherry and eastern redcedar. Cannot be used
as cropland because of doughtiness and rapid
leaching of plant nutrients.
Ousley Fine Sand(OuB) : well drained sand
located on dunes near sound side of the Outer
banks, strongly acid, high water range from 1.5 to
3ft. Used mainly as Woodland. Vegetation includes
live oak, water oak and sweet grass. This land is
generally not used for cropland due to its wetness.
Major Crops: none used.
Soil description for Goshen Ridge
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Yeopim silt loam (YeA) : rarely flooded,
deepest of soil ranges from 3 to 54 inches. .
Location edge of creeks and marshes along
the Pungo River.
Hydeland silt loam Scuppernong muck
(HyA): rarely flooded, major uses cropland
and woodland. Vegetation includes pond
pine, swamp blackgum, switchcane, swamp
chestnut oak and various other types.
Location edge of Pocosin.
Ponzer muck (PnA): surface layer soil
ranges from 0-6 inches subsoil: 6-21 inches,
underlying soil ranges from 21-71 inches.
Roper muck (RoA): rarely flooded, soil
depths: surface: 0-5 inches, subsoil: 5-42
inches, underlying: 42-72 inches. Water
capacity: high. Location edge of pocosion.
Pungo Muck(PuA)
Location: Pocosins and depressions. Soil
depths: surface layer: 0-10 inches. Subsoil:
10-80 inches. Underlying: 80-85 inches.
Major Crops: Corn, soybean, and wheat
Soil Thickness in soil components is rich in
nutrients suitable for vegetation and crop
growth.
Soil Description of Buck Ridge
1988 and 1920
scale:1988:1: mile, 1920:1inch=1 mile
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Augusta Fine Sandy Loam (At) :
level, poorly drained. Dark grayish
brown sandy loam. Soil ranges from
very strong to medium acidity.
Winter coverage helps maintain
productivity. 1988
Belhaven Muck (Ba): Rarely
flooded. Soil ranges from slightly to
extremely acid.1988
Pungo Muck(Pu): Rarely flooded.
Dark grayish brown clay loam. Soil
ranges from strongly to extremely
acid. Used mainly as
woodland.1988
Major Crops: Corn and Soybean
Water Source: Alligator River, Su
and Albemarle Sound.
Norfolk Fine Sand (Ns):1920
Optical Imagery of Goshen Ridge
(IKONOS Hi-Res Panchromatic & Multispectral)
Optical Imagery of Buck Ridge
(IKONOS Hi-Res Panchromatic & Multispectral)
Elevation of Buxton
• LIDAR image data
• Shaded elevation at
two foot intervals
Elevation of Goshen Ridge
• LIDAR image data
• Shaded elevation at
two foot intervals
– Low = -4 ft
– High = 50 ft
• Statistical Anomalies
– Obscuring vegetation
– Note: Canals
Elevation of Buck Ridge
• LIDAR imagery
• Shaded elevation at 2
foot intervals
• Statistical anomalies
SRTM ISAR – Alligator River
(Unfinished Data: Buck & Goshen Ridges)
Finished SRTM ISAR Imagery
http://seamless.usgs.gov/website/seamless/viewer.php
Results
Buck Ridge Data Table
Attributes
IKONOS
Elevation
LIDAR
SRTM
4.0 ft
2.5 ft
Soil 1988
Distance
1.27 mi
0.07 mi
0.97 mi
0.14 mi
Area
62.2 acres
1.1 acres
221.4 acres
166.4 acres
Goshen Ridge Data Table
Attributes
IKONOS
Elevation
IKONOS
SRTM
7.0 ft
4.3 ft
Soil 2001
Distance
0.19 mi
0.05 mi
0.76 mi
0.50 mi
Area
133.1 acres
127.4 acres
233.7 acres
275.2 acres
Croatan Data Table
Attributes
LIDAR
LIDAR
SRTM
Soil 1992
Elevation
3.0 ft
4.8 ft
Distance
0.18 mi
0.11 mi
0.19 mi
Area
7.7 acres
3.1 acres
89.6 acres
Conclusion
• Criteria for hypothesis validation
– Habitable
• Distance and area
– Arable
• Soil types and vegetation
– Defensible
• Location and elevation
• Constraints of the study
– Data
• LIDAR statistical inaccuracies
• SRTM gross spatial resolution (30 m)
– Ground-truth (GPS soil and vegetation samples)
Recommendations
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Historical Map (GIS) Study
Airborne ISAR data
Ground Penetrating Radar data
Ground-truthing
Archaeological Survey
Studying living descendants
Other locations
References
• http://www.lost-colony.com
• Miller, Lee. Roanoke Solving The Mystery Of The Lost Colony
• Kolam IKONOS University of Missouri CS
• Quinn, D.B. The Roanoke Voyages 1584-1590
• Cumming, W.P. The Southeast in Early Maps
• North Carolina Agricultural Extension Service, “Soil Survey of Dare
County”, 1992. sheet no.20.
• North Carolina Agricultural Extension Service, “Soil Survey of
Tyrrell County” 2001. sheet no.9.
• North Carolina Agricultural Extension Service, “Soil Survey of Hyde
County”, 1988.
• sheet no.9.
Acknowledgements
• Dr. Linda Hayden
• Dr. Anne Garland, Dr. Malcolm LeCompte,
Dr. San Juan, Mr. Fred Willard
• URE-OMSS Staff
• Colleagues