Science desk
< February 19	<< Jan \| February \| Mar >>	February 21 >

Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is a transcluded archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

February 20

Seawater taste during ocean acidification

Did the taste of ocean water (seawater) somewhat change due to ocean acidification when compared between pre-industrial and modern periods (say 18th and 21st centuries)? 212.180.235.46 (talk) 14:35, 20 February 2020 (UTC)[reply]

According to Ocean acidification, change in pH level of the ocean has changed less than 0.1 pH units. That sort of difference in pH is well below the difference in tolerance for people to taste, especially as stronger tastes will already be present (the salt) which would likely overwhelm any slight difference in the water. If it were absolutely pure water with no dissolved salts, that difference in pH may be VERY slightly detectable by VERY sensitive people, but even then I am not sure. --Jayron 32 16:26, 20 February 2020 (UTC)[reply]

Pedantry: pure water at room temperature has a pH of exactly 7. For the pH to vary at constant temperature, a solute has to be added, and then it's no longer "pure water". --47.146.63.87 (talk) 01:02, 22 February 2020 (UTC)[reply]

To elaborate, acidic substances produce a sour taste when consumed. However, seawater is basic; it's just slightly less so today. Any difference in taste is due to differing perceptions of the other tastes, and possibly mouthfeel, which often influences the perception of "taste". But as noted, the difference is very slight. It would be an interesting bit of research to see whether there is any perceptible difference. --47.146.63.87 (talk) 01:02, 22 February 2020 (UTC)[reply]

Relative volume of volcanic dykes and associated lava flows

Does someone know a source - or several - which relate the volume of a dyke or intrusion with that of the associated lava flow, such as would be expected during a volcanic eruption where some magma stays in the conduit? Note that I am not asking about the ratio of intrusive vs extrusive rocks in general, only these that are part of a discrete eruption event. Jo-Jo Eumerus (talk) 18:47, 20 February 2020 (UTC)[reply]

I've been wondering about this in relation to sheeted dyke complexes and pillow lavas (or other volcanic) sequences during oceanic crust formation. The lavas (2A) are about 0.5–1.0 km thick and the dykes (2B) are 1.0–1.5 km thick. This suggests (and this is obviously my OR) that on average, for each individual dyking event, signficantly less than half of the magma ends up being erupted. It also assumes that each event involves some degree of eruption. I'll continue my search for sources, although I drew a bit of a blank last time I looked. Mikenorton (talk) 10:31, 25 February 2020 (UTC)[reply]

I admit that I've never heard of dykes that are kilometres thick. I think one big problem is that it's often hard to relate a particular dyke to a particular eruption - or not. Jo-Jo Eumerus (talk) 12:25, 25 February 2020 (UTC)[reply]

Sorry, just to be clear the dykes are on average 1 m wide but the layer that they form in the oceanic crust is 1–1.5 km thick, so that's the average vertical extent. Mikenorton (talk) 12:36, 25 February 2020 (UTC)[reply]

Hrm. To me that sounds like there might not be a 1 dyke, 1 eruption correspondence. I was more wondering about this scenario. Jo-Jo Eumerus (talk) 19:17, 25 February 2020 (UTC)[reply]