Shloka 2.35.14
सुमन्त्रस्य कैकेयी-निन्दा (Sumantra’s Reproof of Kaikeyi in the Royal Assembly)
आश्चर्यमिव पश्यामि यस्यास्ते वृत्तमीदृशम्।आचरन्त्या न विवृता सद्यो भवति मेदिनी।।2.35.14।।
āścaryamiva paśyāmi yasyāste vṛttamīdṛśam | ācarantyā na vivṛtā sadyo bhavati medinī ||
I deem it a wonder that the earth does not split open at once while you commit so dreadful a deed.
It is a wonder that the earth does not split right away when you are perpetrating such an (abominable) act.
Sumantra believes Kaikeyi's act of banishing Rama is so sinful and heavy that Mother Earth should naturally react in horror or be unable to bear the burden of such adharma.
The act refers to Kaikeyi's relentless insistence on sending Rama to the forest for fourteen years and the resulting distress caused to King Dasaratha and the kingdom.