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Evaluating Carolina Bays As Surface Features In A Distal Ejecta Blanket:

Geophysical Flow Analysis Predicts Bay Orientation,

Enables Triangulation To Causal Impact Site

Short Tile: Evaluating Carolina Bays As Surface Features In A Distal Ejecta Blanket

Michael E. Davias1 and Jeanette Gilbride2

Corresponding author address: Michael Davias, Cintos Research, 1381 Hope

Street, Stamford, CT 06907 e-mail: [email protected]

1 Cintos Research (unaffiliated)

2 North Carolina State University

Index Terms: 5420 Impact phenomena, cratering; 6022 & 8136 Impact phenomena; 0933 Remote

Sensing; 0550 Model verification and validation; 0530 Data presentation and visualization; 1928

GIS Science; 1944 Markup Languages; 9350 North America; 5416 Glaciation

DRAFT i Abstract

We present a solution to the genesis of the Carolina bays, which are evaluated as surface features in a distal ejecta blanket. The bays’ characteristic orientations are proposed to be artifacts of the ejecta’s momentum-driven flow. An analytical model was heuristically developed to generate ejecta orientations reflecting geophysical flows, and its results compared to measured orientations at ~150 Carolina bay "fields". Our model's predictions correlate well when an oblique cosmic impact into the Wisconsinan ice sheet in the Saginaw area of Michigan is considered as the impact location. Great-circle distances separating that impact site and all identified bays also correlate well; the bays are distributed along a narrow and symmetrical pair of arcs around the proposed crater. These correlations suggest that a unique geospatial relationship exists between the impact site and the bays. A web-based version of the model is available to facilitate independent testing of the hypothesis.

DRAFT ii Inspirational Quotation

“The Goldsboro ridge is a unique feature on the Sunderland surface and requires special explanation whatever its origin. It must be either an erosional remnant of a once more extensive sediment or a depositional feature. ...The Goldsboro sand overlies the Sunderland Formation conformably. The contact is always abrupt but there is no evidence of deep channeling, basal coarse material, and evidence of weathering at the contact. Even the Carolina Bays do not disturb the underlying Sunderland materials.... The sand in the bay rim is not different from the

Goldsboro sand. Therefore, these Carolina Bays are merely surface features associated with the formation of the ridge.”

[Daniels, R.B., and E.E. Gamble, 1970]

DRAFT iii 1 Introduction

The Carolina bays are perhaps the most enigmatic landforms encountered on the earth. Numbering in the hundred of thousands in North America, these depressions present a unique planform that features a well-developed oval circumpheral rim. Their distinct and persistent geometry and their sheer numbers, in combination with their sharing a common alignment in any one area, drove initial recognition of Carolina bays as unique geological landforms. The visual photography available since the bays were observed from the air in the early 1930’s tells only a part of the story. High fidelity digital elevation maps created with today’s Laser Imaging and Range Detection (LiDAR) systems accentuates their already-stunning visual presentation (Figure 1). While some of these features are easily seen in sand dunes or wind-oriented paleolakes, such comparisons have been found to be unsatisfactory by us. The genesis of the Carolina bays remains today as an unsolved geological mystery.

Researches have universally considered the bays to be formed within or excised from pre-existing hosting strata, which itself was created by well-understood fluvial and eolian deposition (Prouty, 1952;

Eyton & Parkhurst, 1975; Firestone & West, 2008]. In sharp contrast, we propose that the bays are surface imperfections within a blanket of ballistically deposited shattered sedimentary strata (sand), and propose that the bays were generated at time of emplacement by the energetic deflation of steam inclusions. The authors feel this interpretation helps explain many of the bays’ physical characteristics, such as localized bays seen at significantly different elevation, and at times intersecting or overlaying one another. Also explained is a mechanism that could create bays on ridges, the ridges themselves being comprised of ejecta deposition, which is our interpretation of the Goldsboro Ridge in NC

[Daniels, R.B., and E.E. Gamble, 1970].

DRAFT 1 The lack of a correlated impact structure in North America is problematic for any attempt to implicate a cosmic impact in the genesis of the Carolina bays. Our conjecture holds that the impacting object was a massive low-density hydrated silicate object, likely a cometary body, which impacted the earth on a shallow angle, nearly tangential to the earth’s surface. Imaging of the surfaces of solar system terrestrial planets and moons has show that approximately 5% of all craters are created during low angle of incidence – oblique – impacts. These events create a set of recognizable characteristics: oval shape, butterfly ejecta pattern, “no-fly” ejecta area up field, and “blow-out” rim down field. [Herrick,

R.R, 2009; Herrick R.R. and K. Hessen, 2003; Johnson, 1942]. Recent studies suggest that impacts into solid surfaces protected by a layer of low impedance materials generate structures that differ from the classic crater planforms [Schultz, P. H. and A. M. Stickle, 2009]. In our specific case, we invoke the Wisconsinan ice shield as a low-impedance layer protecting the sedimentary strata of the Michigan basin. Excised terrestrial minerals, along with cometary minerals and glacial ice, would be intermixed and distributed as hydrated ejecta in a butterfly flow pattern.

An ejecta curtain wall radiating outward from a cosmic impact should follow a few simple laws of large-scale geophysical flows. If a model could be created to replicate those flows, it may be able to predict the Carolina bays’ orientations. Positive correlations between those predictions and the bays’ actual orientation could be considered strong support for the distal ejecta hypothesis. Once engineered and refined, the model may also be capable of triangulation to the causal crater using actual measured bay orientations.

DRAFT 2 2 Methods

2.1 Determining the Geographical Extent of Carolina bay landforms

Using the facilities and satellite imagery of Google Earth’s Geographic Information System (GIS), augmented with high resolution digital elevation mapping (DEM) data from the USGS, a survey was undertaken to catalogue the full extent of Carolina bays, indexed as localized “fields” of bays. No attempt was made to identify all such landforms; instead the fields are representative of the distribution in a given region.

Identifying Carolina bays on the costal plain is straightforward, given their ubiquity and solid identification, however their planforms are rounded in Maryland and in Georgia, presenting challenges. Also challenging is the increasingly rough terrain seen when moving inland from the costal plain. The ejecta blanket hypothesis maintains that the bays can persist through time only under special circumstances. If the landing area is relatively flat and moist, they will be easily stabilized as bays. If the area is level but dry, the blanket will be reworked by the wind into a generic dune field, obliterating any bay formation. When the landing field is in rough terrain, we propose it is sloughed off. In many regions we successfully pursued the search for bays by examining raised plateaus, as identified in color-ramp hinted digital elevation maps (DEMs) as smoother regions. We suspect that more extensive access to higher resolution DEMs (1/9 arc second), currently only available in North Carolina and

Maryland, would aid in expanding the bays’ identified range.

While there is a great deal of research discussing Carolina bays in the east, little attention has been paid to the significant quantity of aligned, oval-shaped landforms in the Midwest [Zanner, W., 2001]. We interpret these bays as being aligned towards the north east (Figure 1), intersecting the eastern bay’s

DRAFT 3 north-west orientations, and are therefore considered by us to be vital components of the impact crater triangulation network.

From this survey, we have created a catalogue of ~140 “Fields” of Carolina bay landforms, managed in a spreadsheet database and also in a Keyhole Markup Language (kml) metadata file. The catalogue is available for interactive visualization through the use of the Google Earth GIS, by referencing the kml file available online @ http://cintos.org/ge/SaginawKML/Distal_Ejecta_Fields.kmz. A basic listing of the fields is presented in Appendix A.

2.2 Assigning Bay Arrival Bearings

Our hypothesis that a bay’s ovoid shape represents a blemish in a distal ejecta sheet leads to a corollary principal that the direction of arrival is displayed in the planform as a momentum artifact. We propose that the arrival alignment is along the major axis, with the highest rim segment being down-range. To measure and capture this “inferred” alignment, we employ a “Bearing Arrow” with a graticule as an overlay in the Google Earth GIS visualization tool (Figure 1). The overlay is manually rotated so that it aligns with the user’s interpretation of the bay’s orientation and the rotational value is captured in the kml metadata of the element. Since the bays are rarely perfect ellipsoids, the interpretation is better qualified by comparison with numerous companion bays as a “best fit”.

While the bays of North and South Carolina are seen as elongated ellipsoids, many of the bays of

Maryland and New Jersey to the north, and Georgia to the south, do not present the elongation necessary for determining an inferred orientation. What is left, significantly, is a predisposition for having a segment of the enclosing rim that is fatter & higher than the opposing side. For the purpose of this discussion, we have assumed the inferred alignment of circular bays to be from the shallow side to the fat “lip”.

DRAFT 4 2.3 Predicting Carolina bay Orientations

Previous attempts by others at triangulation using the bays’ orientations have failed to produce a focus

[Johnson, 1942]. We propose this to be caused by several large-scale geophysical flow properties not considered. First, that the impact may have been an oblique event, which would infer a chaotic focus.

Secondly, a planetary body rotates during any realistic ejecta loft time. [Wilbur , K.E. and P.H.

Schultz, 2002]. A third variable is the proper accounting for the west-to-east ground-velocity difference between the ejection site and the landing site, which will be resolved as the ejecta re-enters the atmosphere and strikes the earth. Also a factor is the interpretation of a given bay’s orientation, as the bays rarely present a geometrically pure ovoid form [Eyton, J.R. and Parkhurst, J.I., 1975]. This is especially true at the northern edge of their eastern range, where we interpret bays as being “squashed” along the arrival bearing.

2.4 Systematic by Loft Time Adjustment

The kinematic Coriolis force is applied to an object to “force” it along a great circle path as it proceeds along a trajectory. For example, if an object is launched with sufficient velocity on an azimuth of 90 degrees from latitude 45º north (i.e. due East), it will follow a great circle route as it begins to circle the earth’s surface. The Cartesian coordinate “bearing” of our example object begins to “turn” south, and eventually the object will cross the equator on an azimuth 45 degrees increased, or 135 degrees. During an ejecta loft period the earth would be rotating from the west to the east beneath the ejecta’s trajectory path. The landing location of the ejecta will actually be westward of the initial “target”, although it would be imprinted with the arrival bearing to the initial target site. We consider that imprinted value to be our “baseline” bearing, which is further refined in the model’s next step.

DRAFT 5 2.5 Systematic by Latitude Adjustment

While Coriolis force components are systematic by loft time, there is another factor superimposed on alignment that is systematic by latitude [Prouty, 1952]. Here, we account for ground speed differences between any two particular spots on the earth, which is a function of the cosine of the locations’ latitudes. The end cases are the poles – where the ground velocity w>e due to rotation is negligible – and the equator – where the ground speed w>e is ~1,670 km per hour.

In our specific proposal, a relevant set of w>e velocities would be the Saginaw crater – rotating at

1,270 km/hr – and a generic ejecta field such as Bishopville – rotating at 1,382 km/hr. A droplet of ejecta traveling from the north to the south in its great-circle frame of reference would not be affected by that ground and atmospheric speed difference until it approaches the surface of the earth, where atmospheric breaking effects on terminal velocity would be applied. Figure 2 attempts to explain the adjustments we apply to the Systematic by Loft’s baseline bearing to generate a final bearing prediction for a particular bay.

2.6 Spreadsheet-based Analytical Model

We present a model for an ejecta curtain wall radiating outward from an impact site that applies those two geophysical flow adjustments discussed above. Assuming it accurately replicates those flows, it should be able to predict the Carolina bays’ orientations. Numerical methods to evaluate ballistic trajectories at a planetary scale have been developed to generate loft distances and distribution envelopes [Jessup, K.L., et al., 2000]. While those are relevant calculations for some aspects of our study, they do not attempt to predict the ground flow orientations necessary for reverse triangulation where the impact location is not known.

DRAFT 6 Our bay field catalogue spreadsheet was extended to generate predictions based on the loft and latitude adjustments discussed above, allowing for a simultaneous solution to all fields in the database against variables such as proposed impact location, average ejecta velocity and terminal velocity. Those variables were adjusted until all empirically measured alignments were within the calculator's predicted values. Charts are generated within the spreadsheet to correlate the predicted values with those measured empirically, offering an opportunity to tune the calculator’s input variables to identify best-fit solutions simultaneously across all bay fields. The spreadsheet also generates catalogue-wide sets of Google Earth KML to visualize the model’s output in the GIS tool. The model is heuristically focused on the latitude and longitude of the proposed Saginaw crater’s three control points (NE,

Centroid and SW).

2.7 Tool for Independent Testing of Hypothesis

To facilitate independent testing of the hypothesis, a web-based version of the model has been made available for integration with Google Earth’s GIS: (http://cintos.org/java/PredictBearings). Using the

Google Earth “Placemark” metadata element, a bay’s latitude and longitude are captured and annotated. The analytical model processes the placemark and generates a predicted orientation for visualization in Google Earth. The calculator can also reverse the process, and provide a “walk-back” to a putative crater by processing a user-adjusted Bearing Arrow element as the input datum. In all cases, the data transfer is accomplished by using kml metadata.

DRAFT 7 3 Results

3.1 Initial Identification of the Cosmic Impact Location

Using the empirically measure arrival bearings of an initial 40 Carolina bay fields, we generated great circle paths for visualization in Google Earth. This yielded a fuzzy triangulation locus at 43.5 north,

89.5 west. Our analysis implies that this simple great circle triangulation would yield an erroneous

“surrogate” impact crater location offset to the west. The Systematic by Loft Time concept places the actual impact crater somewhere along a path extending due east from the surrogate crater location. We heuristically examined various geological depression found along that transit, and selected the Saginaw area of Michigan’s Lower Peninsula (LP) for further analysis. Our proposed impact site represents approximately a 22 minutes loft time offset (equating to 5.5 degrees longitude rotation). Further refinement using the Systematic by Latitude concept in our analytical model is shown to reduce actual loft time to a more realistic 4 to 8 minutes.

3.2 Correlation of Bay Distribution

The flight lines, distances and bearings of all catalogued Carolina bay fields were analyzed for correlation to the proposed surrogate impact crater site. Our first correlation considered the great circle distance from each field back to the proposed impact site and their symmetrical distribution around it.

As shown in figure 3, a very high degree of correlation is seen, suggesting that the bays are geographic distributed along a narrow and highly symmetrical pair of “butterfly” arcs centered on the triangulated

Saginaw impact location. Such a distribution is suggested in the current research on oblique impacts.

The lack of ejecta directly down-range in the “blow-out” zone is expected. Loft distance to the

Midwest are nearly identical to those in Southeastern areas, suggesting a general trend of longer loft distances down range compared to those oblique to the crater’s major axis in the Northeast, where the

DRAFT 8 shortest loft distances are documented. We note that areas north of the impact site’s latitude were covered in glacial ice sheet, prohibiting formation of identifiable bays in those areas.

3.3 Correlation of Bay Orientations

The ~140 evaluated bay “fields” represent many thousands of individual bays, and our solution sets are computed for all fields simultaneously. The chart in Figure 4 presents the results using our current best-fit parameter settings of 3km/sec average ground velocity and a droplet Cd of 0.3 (yielding a terminal velocity of ~270 m/sec). A high degree of correlation is shown between the empirically measured bearings and the predicted bearings. While it would seem plausible that the ejecta at any given location may actually have a density or velocity different from other locations, the model did not have to leverage such fine-tuning to arrive at satisfactory solutions for all evaluated fields.

4 Discussion

4.1 Carolina bay Genesis

In the introduction to his 1942 scholarly examination of numerous then-current hypotheses, Johnson noted, “No one has yet invented an explanation which will fully account for all the facts observed”, a situation the authors believe continues to be true. This paper is not intended to offer an extensive review of “the facts observed”. However, we do share here a few aspects we view as pertinent. The ejecta deposition hypothesis attempts a solution by rolling back many tens of thousands of years of gradualistic process to discover the structural morphology that was inherited by overlying sediments.

We posit that relatively shallow basins were created as surface features during the energetic deflation of steam inclusions in the ejecta blanket; effectively “popped bubbles”. The variety of scale and geospatial distribution of bays within clusters is a direct result of a purely physical fractal process, as

DRAFT 9 the frothy slurry spread downrange across the host terrain. An assumed high temperature and high- pressure emplacement would have created strata that, while unconsolidated, would be more dense and solidified than expected and thus capable of maintaining its structural integrity across time. Bulk ejecta at a given field of bays is likely derived from the shattering of a common localized sedimentary unit during the crater excavation, offering a site-specific grain size and mineral constituency that would vary at other bays as the crater excavation proceeded across the length and depth of the structure.

A detailed examination of Nebraska basins has shown that late Wisconsinian loess deposits were draped evenly over underlying course sand basin structures, smoothing the basins’ sharp rim relief, however not affecting their overall geometric planform [Kuzila, M.S., 1994]. Similarly, we see the eastern ejecta blanket as a palimpsest over which much geological history was written in the form of lacustrine and eolian development within and about those basins.

4.2 The Saginaw Impact Crater

The authors are quite respectful of the long-standing acceptance of the Saginaw area as a glacially carved landscape. Our proposal leverages the presence of a multi-kilometer thick ice sheet over the LP at impact dates between 20kya to 40kya. The ice sheet offers a rationale for the relatively shallow

“crater” seen in the area today, while at the same time providing the significant volume of water necessary to create the posited hydrated slurry. Implicating the ice sheet also provides a vehicle to re- distribute the local crater ejecta across a wide area as “glacial till”. Figure 5 presents a cross-section schematic of the proposed crater.

The bedrock across the central LP is composed of later, more solidified carbonate rocks, whereas the older underlying rocks are softer shales and sandstones built up prior to the origins of life. It is generally understood that ice age glacial activity removed vast quantities of the softer strata from

DRAFT 10 around the basin’s periphery (i.e., Lakes Michigan, Huron and Erie), however they were unsuccessful in breaching the carbonate layers’ cuestas encircling the center of the basin with one major exception –

Saginaw Bay [Rieck and Winters, 1982],

Using remote imaging tools, we have noted that the Saginaw region exhibits a geometrically oval shaped depression, oriented SW to NE, which correlates well with our Carolina bay “butterfly” distribution symmetry. We note the strong geometric trend correlation with our proposed oval crater across the northern and southern rims, as well as its overlap of the Kankakee Torrent source at the southwestern end. Experimental and planetary imaging has identified oblique impact craters as displaying the deepest excavation at the up range end of the crater, which here falls in the northeast end of our proposed Saginaw crater. This point correlates with one of the deepest areas of Lake Huron – the Bay City Basin. Another common attribute of an oblique impact is the existence of a slight ridge – likely rebounded strata – tracing a line down the center of the structure. Here, the Charity Islands are set in the bay along the oval’s centerline.

We fully expect that the Huron lobe of the Ice sheet would have eventually advanced into the excavated crater from the Huron basin in the northeast, bulldozing the collapsed ice crater ramparts and leaving the existing set of terminal moraines behind as it deglaciated at the onset of the Holocene.

A significant list of geological anomalies has been identified and is available for review on our web site’s Saginaw Crater section.

4.3 Timing of the Manifold – some constraints

We propose that all Carolina bay landforms were formed in a few short moments during the late

Pleistocene era, 20 kya to 40 kya.

DRAFT 11  Researchers are confident that the “Saginaw Lobe” of the ice sheet was removed prior to 15

kya, as indicated by dated flows into the area from the Michigan and Erie lobes [Brown, S. E.,

et al, 2006]. We propose that the impact event was responsible for that removal at a time

inconsistent with the continued presence of the Michigan and Huron/Erie lobes.

 Our scenario suggests that the “crater” in the ice sheet would have filled with liquid water and

then eventually drained disruptively to the south in an event know as the Kankakee Torrent,

which occurred sometime prior to18 kya.

 The bays in Nebraska have been identified as paleobasins formed prior to Wisconsinan

deposition of a losess blanket dated at ~ 27 kya [Kuzila, M.S., 1994].

 Ancient Baldcypress trees found buried under 10 meters of white sand in the PeeDee river area

of North Carolina are dated as being 25 to 40 thousand years old. [Stahle, D.H., 2005]

5 Conclusion

Our hypothesis holds that 20 kya to 40 kya a catastrophic impact manifold deposited a blanket of distal ejecta up to 10 meters deep in a set of butterfly arcs across the continental US. We have modeled the blanket as a ballistically deposited hydrous slurry of sand and ice originating from a cosmic impact into the Wisconsinian ice sheet, and propose that Carolina bay landforms were created during the energetic deflation of steam inclusions at the time of ejecta emplacement. In geographic areas presenting a favorably level hosting terrain and a relatively high water table, the paleobasin foundations of the bays were found to have persisted over the intervening millennia, in spite of being overlain with losess and subjected to water and wind erosion and reworking.

A analytical model was developed to predict the expected trajectories and emplacement orientation characteristics of the hypothetical ejecta blanket, and was expanded to "reverse" the geophysical flows,

DRAFT 12 such that a given bay’s empirically measured orientation could be used to generate a "walk-back" triangulation trajectory to validate the impact site identification. As the model was researched, progress was shared with the Google Earth Community through a thread, Inferred Orientation of Distal Ejecta.

We presented evidence that, when applying a unique combination of impact location (Saginaw), average ejecta curtain wall velocity (3 km/sec) and ejecta terminal velocity (270 m/sec), the model’s prediction of any given bay’s orientation correlates well with the empirically measured orientation of that bay. Significantly, the correlation is seen at all ~140 disparate clusters of Carolina bays in our catalogue. We also note that the distribution of bays is highly symmetrical around the proposed impact’s azimuth.

The authors maintain that the correlations presented here demonstrate that a unique geospatial relationship exists between all known Carolina bays and the Saginaw region, a result that presents a strong argument for the ejecta blanket manifold hypothesis. Further research is proposed to investigate

- in the context of our hypothesis - the true geomorphological nature of Michigan’s Lower Peninsula and of the enigmatic Carolina bays.

6 References

Brown, S. E., Newell, W. L., Stone, B. D., Kincare, K. A., and O'Leary, D. W., 2006, New regional

correlation of glacial events and processes in the interlobate area of southern Michigan and

northern Indiana after the last glacial maximum (LGM), Geological Society of America Abstracts

with Programs, v. 38, no. 4, p. 58

Daniels, R.B., and E.E. Gamble, 1970, The Goldsboro Ridge, an Enigma, Southeastern Geology vol.12

(1970) pp151-158

DRAFT 13 Eyton, J.R. and Parkhurst, J.I., 1975, A Re-evaluation of the Extra-terrestrial Origin of the Carolina

Bays, Occasional Publication, Dept. of Geography Paper No. 9, University of Illinois at Urbana–

Champaign, p 45

Herrick R.R. and K. Hessen, 2003, The Impact Angles Of Different Crater Forms On Mars, Lunar and

Planetary Science XXXIV, pp 2122.pdf

Jessup, K.L., et al., 2000, Icarus, 146, 19

Johnson, D. W., 1942, The Origin of the Carolina Bays, Columba Geomorphic Studies Volume IV,

New York: Columbia University Press

Kuzila, M.S., 1994, Inherited Morphologies Of Two Large Basins In Clay County, Nebraska, Great

Plains Research 4 (February 1994): p 51-63

Prouty, W. F., 1952, Carolina Bays and their Origin, Geological Society of America Bulletin vol. 63,

no. 2, pp. 167–224.

Rieck, R.L. and H. A. Winters, 1982, Characteristics of a Glacially Buried Cuesta in Southeast

Michigan, Annals of the Association of American Geographers, Vol. 72, No. 4 (Dec., 1982), pp.

482-494

Schultz, P. H. and A. M. Stickle, 2009, Lost Impact, AGU Fall Meeting 2009, Presentation ID#

PP33B-04

Stahle, D.H., et al, 2005, Ancient Baldcypress Forests Buried in South Carolina, on line @

http://www.uark.edu/dendro/subfossil.pdf

Wilbur , K.E. and P.H. Schultz, 2002, The Effect Of The Coriolis Force On Distal Ejecta Deposits On

Mars, Lunar and Planetary Science XXXIII, pp 1728.pdf

DRAFT 14 7 Appendix A http://cintos.org/Papers/GRL_Submission/Field_List.pdf

List of Carolina bay fields under evaluation

8 Figures

Figure 1 – Defining Carolina bay Orientations

Clay County, Nebraska area Color Ramp DEM using NED 1/3 arcsec datum prepared in Global

Mapper . Shown are numerous paleobasins similar to eastern Carolina bays. The “Bearing Arrow” overlay shown allows for assigning an arrival bearing as interpreted by the user.

Figure 2– Bearing Prediction Trigonometry

At time of atmospheric re-entry into the 165-km/hr west-to-east “slipstream”, the ejecta’s trajectory will be skewed. In this case the velocity difference was additive to the ejecta’s w>e velocity vector, and our prediction calculation needs to subtract it back out. Since the n>s velocity vector is constant, the effective alignment rotates slightly clockwise.

The graphic uses metrics of Wagram, NC:

Crater Latitude: 43.6º bay Latitude: 34.9º Droplet Cd: 0.3 3-D Terminal Velocity: 330.0 m/s In Ground Plane: 233.0 m/s W>E component: 165.0 m/s Ground Velocity Delta: 44.0 m/s De-Skewed W>E 121.0 m/s Inferred Bearing: 135.0º De-Skewed Bearing: 143.9º

DRAFT 15 Figure 3– Distribution of Carolina Bays Around Saginaw Crater

Distribution of bays demonstrates geospatial symmetry around the proposed Saginaw crater. Note that glacial ice coverage prohibited bay formations in more northerly areas. Areas directly down the impactor’s arrival azimuth were in the “blow-out” zone, where little ejecta is expected. The graphic can be re-created in Google Earth using the kml file: http://cintos.org/ge/SaginawKML/Ejecta_Butterfly.kmz

Figure 4 - Correlation of Predicted Bay Orientations to Measured

Plots of the model’s predicted arrival bearing at each field, assuming it had been ejected from the crater’s centroid (green line), against the empirically measured inferred orientation at that field (blue line). The purple and red lines represent bearing predictions for ejecta lofted from the northeast and southwest ramparts of the crater, and are effectively control bounds for the fuzzy orientations expected from a large impact. Vertical axis displays the arrival bearing in degrees. Horizontal axis displays the state names of the bay fields, ordered clockwise from New Jersey.

Figure 5– Impact Crater Cross-section cartoon

An oblique strike into a thick continental ice sheet over the proposed Saginaw region would first excise

1 to 2 km of ice before penetrating into terrestrial sedimentary layers. Local ejecta will be deposited on the ice sheet, allowing for eventual distribution as common glacial till.

DRAFT 16

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