Don't confuse this sal-, sali-; "salt" unit with another sali-, salt- unit which refers to "jumping" and "leaping".
The domes push their way up through more brittle overlying rocks, are roughly circular, and average up to one to two miles in diameter. The tops of these domes can be commercially mined for salt.
The middle (gradient) zone acts as a transparent insulator, permitting sunlight to be trapped in the bottom layer (from which useful heat is withdrawn).
This middle layer, which increases in brine density with depth, counteracts the tendency of the warmer water below to rise to the surface and lose heat in the air.
Such wells were an early source of oil in the United States oil industry.
2. Etymology: Saltpeter is a borrowing of Old Middle English salpetre [about A.D. 1300]; a borrowing of Old French, salpetre, a learned borrowing from Medieval Latin; also borrowed directly from Medieval Latin sal petrae, "salt of rock"; from Latin sal, "salt" + petrae, genitive form of Latin petra, "rock".
It comes from Latin, sal,, "salt", referring to a "brine dressing" or "pickle". This meaning later evolved into Italian and Spanish salsa, and French sauce, from which English gets sauce.
The modern application to a "dish for a cup" did not evolve until the 18th century.
2. A reference to an impudent (lacking respect and showing excessive boldness) or impertinent (rude and lacking respect) manner.
2. Amusingly forward and flippant.
b. Impertinent in an entertaining way; impossible to repress or control.
3. Etymology: "resembling sauce", later "impertinent, cheeky" (1530),; from sauce.
The connecting notion is the figurative sense of "piquancy in words or actions." From Old French sauce, sausse, from the noun use of Latin salsa, salsus, "salted"; from Old Latin sallere. "to salt" which came from sal, salis, "salt".
Sauce malapert, "impertinence" (1529), and the slang phrase to have eaten sauce or to "be abusive" (1526).
Originally, it referred to any dish made by “salting”.
It apparently came from a reference to the mud in salt flats by river estuaries and it seems to be etymologically related to “salt”. It was probably borrowed from a Scandinavian word because Danish and Norwegian both have the related sylt, “salt marsh”.
2. Pickled food; especially, pork trimmings.
3. Etymology: to soak something in "salt"; "to pickle or steep in vinegar"; from Old French sous, "preserved in salt and vinegar"; related to Old Saxon sultia, "salt water".