In Act 1, scene 3 of Romeo and Juliet, Lady Capulet tells Juliet, "Well, think of marriage now" Can anyone tell me what technique has been used?

In this scene, Lady Capulet asks Juliet:

... How stands your disposition to be married?

To which she replies:

It is an honour that I dream not of.

Juliet is quite sarcastic in her response. She deliberately and ironically uses the word 'honour' when, in fact, she does not deem it an honor at all. She is just not interested in being wed.

Her mother then responds:

Well, think of marriage now; younger than you,Here...

In this scene, Lady Capulet asks Juliet:

... How stands your disposition to be married?

To which she replies:

It is an honour that I dream not of.

Juliet is quite sarcastic in her response. She deliberately and ironically uses the word 'honour' when, in fact, she does not deem it an honor at all. She is just not interested in being wed.

Her mother then responds:

Well, think of marriage now; younger than you,
Here in Verona, ladies of esteem,
Are made already mothers: by my count,
I was your mother much upon these years
That you are now a maid. Thus then in brief:
The valiant Paris seeks you for his love.

The technique Lady Capulet utilizes to persuade Juliet is called Fallacy. In this instance, the fallacy takes two forms: Firstly, she makes an appeal to popular opinion by telling Juliet that ladies of stature even younger than her, are already mothers, suggesting that that is the trend and she should therefore follow suit. 

Secondly, she makes an appeal to authority by attempting to win Juliet's confidence in telling her that she was already mothering Juliet at much the same age that Juliet is at now. As an authority figure, she believes that Juliet will understand that, because she, her mother, had married early, it should be the same for Juliet.

Juliet, however, is not entirely convinced and later states:

I'll look to like, if looking liking move:
But no more deep will I endart mine eye
Than your consent gives strength to make it fly.

Juliet means that she would peruse Paris and she if through her perusal, she likes what she sees, but she will not look any deeper than her mother allows her to. Her statement is quite ambiguous since the implication is also that she will act as if she is interested by looking at Paris if that is what will please her mother, but that she will not look any farther than she is allowed to - she will therefore not critically scrutinize Paris if that is her mother's wish.

In all, she grudgingly acquiesces to her mother's request.