Naslov
Possible lava flows on the red planet: the key for the mathematical approach in computing how deep Martian oceans were during each period of the planet history. (Abstract)

Autori
Salamunićcar, Goran

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
34th COSPAR Scientific Assembly & The Second World Space Congress (WSC2002) ; no. B0.4-C3.4-0016-02 / - Houston (TX), 2002

Skup
COSPAR Scientific Assembly (34 ; 2002) ; World Space Congress (2 ; 2002)

Mjesto i datum
Houston (TX), Sjedinjene Američke Države, 10.2002

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Mars; ocean

Sažetak
Covering certain area of the planet long enough and accumulating the impacts of meteors, ocean prevents appearance of craters on the surface. Even if ocean dries up once, associated territory will still contain relatively smaller number of craters. Mathematically, this influence can be described as correlation between topology profile of the planet and distribution of craters. However, large lava flows can also erase craters from the surface, so we can not directly determine from the correlation whether the oceans existed and how large they were. If the possible lava flows could be determined, then it would also be possible to compute whether the remained territory - not flooded with the lava - had been covered by the ocean, because nothing else can influence the correlation in such large amount (a meteor large enough to erase almost all other craters from the Martian northern hemisphere would certainly leave clearly visible trace, while atmosphere would pass trough only large meteors and would erase all small craters in lowlands by winds and sand-storms). Using precise topographic globes obtained by the Mars Orbiter Laser Altimeter, all possible lava sources can be marked, and then, through the simulation, all territory that could have been flooded by the lava can also be excluded from computations. However, we do not know exactly how much the planet topography was changing. To solve the problem, simulations were made assuming different changes of the planet topography resulting in different areas that could have been flooded by the lava. In all cases, from the most optimistic one where insignificantly low percentage of the planet territory is excluded, to the most pessimistic one where most of the planet territory is excluded, results were always the same with only slight differences in precision. This leads to the conclusion that the lava could not have influenced the correlation in required amount, leaving the oceans as the only possible explanation. Once this was confirmed, the lava-flow simulation that most closely matches the lava-flows visible on images obtained by the Mars Orbiter Camera was chosen, resulting in as precise input for mathematical analysis as possible. The obtained pairs (ocean depth in meters, time in millions of years) are: (9688, -4750), (9688, -4500), (9621, -4250), (9554, -4000), (9489, -3750), (9422, -3500), (9351, -3250), (9276, -3000), (9141, -2750), (6867, -2500), (6569, -2250), (6328, -2000), (6157, -1750), (5928, -1500), (5660, -1250), (5276, -1000), (4742, -750), (4425, -500), (3901, -250), (3728, -200), (3501, -150), (3107, -100), (0, -50).

Izvorni jezik
Engleski

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