T43 Flyby (May 12, 2008), Tui Regio, Tortola Facula (the Snail), and NE Shangri-La Options

[titanicrivers]

It’s a pity Cassini can’t be put into a polar orbit around Titan so that areas of interest can be viewed repeatedly and topographic maps constructed to help confirm implied topography from the SAR images. There is a topographic map of ‘Kodiak’ island and nearby polar sea and river eroded landforms as shown in 1) below. The ‘ridges’ you have identified donot stand out very well on the topo map. This may result more from the lower resolution of the topographic map. Alternatively the ridges may just appear as such and not be linear tectonic elevations like the ones just imaged in Xanadu. By examining the drainage patterns of the rivers one can infer some topographic sense of the land drained. In this case the drainage pattern supports the notion the ridges are higher ground. They are somewhat wavy and don’t sport tectonic fracture so they may have been formed differently.

1)

[Juramike]

Ahhh, but just slightly to the S of the image above (and just barely missed by the PIA10353 topgraphy overlap) is an area that has very long parallel streams.

These streams were previosly mentioned in the Titan's Lakes Revealed thread, post 252 (link here) and also in the T28 Flyby thread, post 75 (link here, note Olvegg's indications of directional flow, this must have a really interesting dynamic!)



These streams do not branch very extensively and seem set in their little valley. (Compare with the dendritic set just to the NW). The two running alongside each other look like a great candidate for river capture, so something must be keeping them from apart.

I would assume that the streams are sitting in NW to SE trending creases (under tectonic control?). The topographical image PIA10353 just shows that the downstream part is at the most only tens of meters different in elevation. According to the topo image, any ridge in the downstream section between the two streams could only be 10's of meters high at the most, so to topography here is subtle.

-Mike

[titanicrivers]

Most interesting! The rivers of PIA09217 (T28 SAR) are my favorite! The topographic map catches them in their lower reaches where they are distinct and fairly straight running in a low relief partially flooded plain. Their upper reaches show tributaries with greater tortuosity draining regions that have greater apparent topographic variation and elevation (SAR appearance only). The presumption is they are flowing full with the seasonal polar monsoons raining liquid hydrocarbons. While the lower reaches are fairly straight and perhaps are confined to tectonic wrinkles they are not as straight as other channels that seem to occupy tectonic faults as shown in the images below.


I wonder if some of the low wiggly ridges pointed out by Gladstoner are eskers from a previous climatic period of colder polar conditions.

[Juramike]

I lined up some of the features indicated by Gladstoner, titanicrivers and myself onto the North Polar RADAR Swaths graphic PIA10008:



Ridges, graben, and presumed stream divides are indicated with a black line.
In dashed blue are close alignments of lake chains. (In one case in T19 the lake chain direction lines up nicely with stream divides).

The graphic on the right is the same image with much of the extraneous stuff removed for clarity.

There could be a pattern...(or two)

The T29 RADAR Swath will be key.


-Mike

[ngunn]

There could be a pattern...(or two)

-Mike

Mmmm . . the patterns appear to follow the swath directions. I'm sure you've eliminated obvious artifacts, but even so it makes me wonder if along-swath ridges are picked out by the radar better than ones at other angles.

[Phil Stooke]

"it makes me wonder if along-swath ridges are picked out by the radar better than ones at other angles."

That is absolutely true and a well known problem in SAR interpretation. Not just SAR - all linear relief features are best seen if illuminated perpendicular to their long dimension in all images - I'm seeing the same on Eros now. Since SAR is illuminated from the side, the above statement follows naturally.

Phil

[Juramike]

I agree. I was really looking to find somewhere up in the polar regions where the ridge/drainage/graben pattern was perpendicular to the swath direction.

Only the T21, T25, and T28 regions in the lower-mid latitudes have a clear ridge pattern at a steep angle to the swath direction.

This is another reason why the T29 Swath would be key. It would help confirm the continuation of the v. slight off angle pattern of the left polar section of the T28 Swath (where there appears to be tectonic/fault control to the stream drainages as titanicrivers pointed out) with the area of the T19 Swath.

A perpendicular swath across one of these tentatively identified ridge/drainage/graben patterns would also help confirm that it's not just an angle effect. Maybe in the XM? (XXM?) ((3XM?))

-Mike

[peter59]

T43 - Equatorial Anti-Saturnian hemisphere (Dilmun, Northern Shangri-la, Tortola Facula, Central Xanadu)

[peter59]

and T43 - Targeted Distant look (Western Tui Regio)

[Jason W Barnes]

and T43 - Targeted Distant look (Western Tui Regio)

Dang -- unfortunately hard to see much in the distant view here. We need high-res, either VIMS or RADAR, I'm not particular! Okay, yes I am. Lets try VIMS

- VIMS Jason

[Juramike]

T43 SAR RADAR Swath released as PIA12988