أَثْقَالَهَا

أَثْقَالَهَا is a phrase (شِبْهُ الجُمْلَةِ) consisting of a possessed noun and a possessive noun compound

PhraseNoun / NounNoun Noun
شِبْهُ الجُمْلَةِمُضَافٌ وَ مُضَافٌ إِلَيْهِمُضَافٌ إِلَيْهِمُضَافٌ
PhrasePossessive compoundPossessive noun/ownerNoun possessed/owned
her burdensأَثْقَالَهَا=هَا+أَثْقَالَ
burdens of hershersburdens of
Surah/Below is the only verse in the holy Quran containing the possessive nominal compoundأَثْقَالَهَا
Verse
99-2and the earth throws out its burdensوَأَخْرَجَتِ الأَرْضُ أَثْقَالَهَا