Timeline for Could there be caves on Mars in the areas inside Jezero crater and the watershed west and north of it where the Mg carbonates are detected?
Current License: CC BY-SA 4.0
14 events
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| Jul 1, 2022 at 20:41 | comment | added | Cornelis | Good to learn ! I found another article with which I could try to answer my question. | |
| Jul 1, 2022 at 17:52 | comment | added | Fred | Most definitely! Nickel from ultramafic rock is the main source of nickel sulfides globally. It occurred as a sulfide within the ultramafic melt & precipitated out when the melt cooled. Cu, Fe & other sulfides occur as part of the mix. In Australia the economic sulfides are Ni. Cu values are very small. In Canada (Timmins & Sudbury, Ontario) it tends to be both Ni & Cu. Voisey Bay in Labrador Canada its Ni, Cu, Co. At Norilsk in Russia its Ni, Cu & Pt group elements (PGE/PGM). Even lateritic nickel (oxides) occur in highly weather ultramafic rock (Cuba & New Caledonia). | |
| Jul 1, 2022 at 10:02 | comment | added | Cornelis | That's interesting, but was the percentage high enough to mine them economically ? And is there any clue where to look for those metals underground ? | |
| Jun 30, 2022 at 18:40 | comment | added | Fred | Neither magnesium or iron, but nickel. In one case getting through ultramafic to get to mafic which had gold. | |
| Jun 30, 2022 at 12:57 | comment | added | Cornelis | But the examples in the article are veins of magnesite (MgCO3) inside ultramafic rock ! | |
| Jun 30, 2022 at 12:02 | comment | added | Fred | I know. I've been involved with digging many large tunnels in ultramafic rock. Ground conditions in ultramafic rock are always a cause of concern. Mafic rock generally have better ground conditions than ultramafic. Some ultramafic lava flows can several tens of meters thick, particularly if multiple flows have occurred on top of each other. Some ultramafic flows can ultimately be in the hundreds of meters thick. Both mafic & ultramafic rocks don't dissolve by the action of water as limestone does. Karst type caves don't occur in mafic or ultramafic rock; they're more competent than limestone. | |
| Jun 30, 2022 at 11:37 | comment | added | Cornelis | Ultramafic rock-hosted veins (b) don't have to be formed by lavas and can be large ! Section 2.1 in the article has the following examples: a) The Semail ophiolite has magnesite occuring in veins up to a few meters thick. b) Within ophiolite blocks in NE Iran are magnesite veins up to 10-m thick. c) Vein deposits from the Balkan Peninsula have a thickness of up to 20 m. | |
| Jun 29, 2022 at 17:45 | history | edited | Fred | CC BY-SA 4.0 |
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| Jun 29, 2022 at 9:56 | comment | added | Fred | ... Sect. 4.1.2 mentions the mottled terrain & the paper states "The light-toned floor unit ... is often covered by aeolian dunes, and appears pervasively fractured when exposed below the dunes." The pervasive fracturing is the intriguing bit concerning what might occur underground regarding voids. The size of the fractures & the effects of water flows through the cracks would be interesting. | |
| Jun 29, 2022 at 9:47 | comment | added | Fred | @Cornelis: I'm still pondering. My initial thoughts are no caves. Your ref Carbon sequestration on Mars states, "no massive carbonate rock reservoir on Mars has been identified to date". So no-one has yet identified anything like the limestone country along the Croatian coast (karst), the "white cliffs of Dover" in England or the Nullarbor Plain in southern Australia. So Mars won't have karst regions. Re: the mottled regions mentioned in your last ref. There's a lot a swelling clay (smectite) which derives from weathered gabbro. So that's not hopeful. ... | |
| Jun 29, 2022 at 9:21 | history | edited | Cornelis | CC BY-SA 4.0 |
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| Jun 28, 2022 at 18:35 | history | edited | Fred | CC BY-SA 4.0 |
Grammatical correction
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| Jun 28, 2022 at 9:02 | comment | added | Cornelis | I didn't mean to get one suffering, only thinking like "hey, that's a good question !". :) Yes, it doesn't look good for caves, at least inside Jezero crater. I think the watershed could be more promising with the scenario of water percolating in a warmer subsurface crust, as suggested by the latest article I cited. where also the "mottled terrain "is described, as being heavily degraded and with exhumed appearance and circular features likely to be degraded impact craters. Any opinion about that ? | |
| Jun 27, 2022 at 19:42 | history | answered | Fred | CC BY-SA 4.0 |