Matsya Purana — Cosmography of Jambūdvīpa: Varṣas
अशीतिर्हिमवाञ्छैल आयतः पूर्वपश्चिमे द्वीपस्य मण्डलीभावाद् ध्रासवृद्धी प्रकीर्तिते //
aśītirhimavāñchaila āyataḥ pūrvapaścime dvīpasya maṇḍalībhāvād dhrāsavṛddhī prakīrtite //
The Himavān mountain-range extends eighty (yojanas) from east to west. And because the continent assumes the form of a circular disc, its decrease and increase (in breadth) are described.
It does not narrate Pralaya directly; it presents a cosmographic principle—since the landmass is conceived as a circular maṇḍala, its dimensions are discussed in terms of expansion and contraction, a framework often used in Purāṇic world-modeling.
Indirectly: by grounding dharmic life in a mapped sacred world (dvīpa, mountains, measures). Kings are expected to understand and uphold the cosmic order reflected in geography and boundaries; householders use such cosmography to orient pilgrimage, ritual directionality, and sacred spatial awareness.
The key term is maṇḍalī-bhāva (circular/mandala form), which echoes Vāstu thinking: sacred space is organized as a mandala. While not a building rule itself, it supports the mandala-based cosmic geometry later applied to temple plans and ritual spatial layouts.