Eustatic lake level and source change had resulted in intercalation development in braided delta system.
湖面的升降和物源的摆动使辫状三角洲沉积体系中发育夹层。
英语百科
Sunflower (mathematics)
In mathematics, a sunflower or -system is a collection of sets whose pairwise intersection is constant, and called the kernel.
The -lemma, sunflower lemma, and sunflower conjecture give various conditions that imply the existence of a large sunflower in a given collection of sets.