intrusion

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intrusion

1. Geology
a. the movement of magma from within the earth's crust into spaces in the overlying strata to form igneous rock
b. any igneous rock formed in this way
2. Property law an unlawful entry onto land by a stranger after determination of a particular estate of freehold and before the remainderman or reversioner has made entry

Intrusion

 

a geological term used in two senses:

(1) The process of magma injection into the body of rock that forms the earth’s crust. The solidification of such injected magma leads to the formation of intrusive rock.

(2) An intrusion is a geological body composed of igneous rock and formed in the process of injection and solidification of mag-matic melt in the earth’s crust (intrusion, intrusive body, plutonic intrusion). In relation to the structure of the country rock, intrusions are classified as concordant and discordant. The first group includes sills, laccoliths, and lopoliths, and the second group includes batholiths, stocks, and dikes. Intrusions are classified according to the depths at which the magmatic intrusion occurred as deep-seated intrusions (abyssal) and shallow-depth intrusions (hypabyssal). In this context the conditions of cooling of the magma and its effect on surrounding rock differ sharply. At shallow depths the cooling is rapid and fine crystalline or porphyritic rock is formed, and contact metamorphosis affects a small area of the country rock. At great depths medium-grain and large-grain rock and major changes in the surrounding rock are characteristic.

intrusion

[in′trü·zhən]
(geology)
The process of emplacement of magma in preexisting rock. Also known as injection; invasion; irruption.
A large-scale sedimentary injection. Also known as sedimentary intrusion.
Any rock mass formed by an intrusive process.

intrusion

Unauthorized access to a computer system or network. See intruder and IDS.
References in classic literature ?
I trust your majesty will pardon this intrusion on her meditations, but a foreign lord has arrived from England and waits in the parlor, demanding the honor of presenting a letter to your majesty.
Secure from female intrusion, there was no restraint upon the hilarity of the warriors, who, like the gentlemen of Europe after the cloth is drawn and the ladies retire, freely indulged their mirth.
They behaved very well, however, to him on the occasion, betraying no exultation beyond the lines about the corners of the mouth, and seemed to think it as great an escape to be quit of the intrusion of Charles Maddox, as if they had been forced into admitting him against their inclination.
They, at that time, were extremely numerous, and conducted the chief navigation and commerce of the Ohio and the Mississippi, as the voyageurs did of the Canadian waters; but, like them, their consequence and characteristics are rapidly vanishing before the all-pervading intrusion of steamboats.
it is bad enough to intrude in this way, and I do not know what you can say or think of the time selected, for the intrusion.
It was plain that for some reason or other she had not wished him to visit her, and he felt his call to be somewhat of an intrusion.
Henry Tilney," with the embarrassment of real sensibility began to apologize for his appearance there, acknowledging that after what had passed he had little right to expect a welcome at Fullerton, and stating his impatience to be assured of Miss Morland's having reached her home in safety, as the cause of his intrusion.
Though the conversation was very incoherent and Vera was angry at the intrusion of the masculine element, both husband and wife felt with satisfaction that, even if only one guest was present, their evening had begun very well and was as like as two peas to every other evening party with its talk, tea, and lighted candles.
I must apologize," the newcomer said, "for my intrusion.
Her assumption of equality with him was disconcerting, and at times he half-consciously resented the impudence and bizarreness of her intrusion upon him--rising out of the sea in a howling nor'wester, fresh from poking her revolver under Ericson's nose, protected by her gang of huge Polynesian sailors, and settling down in Berande like any shipwrecked sailor.
They resented Michael's intrusion on the instant, spitting, lashing their long tails, and crouching to spring.
I beg to apologise for my intrusion, Miss Lockwood.