Igama elithi "A horizon" livame ukusetshenziswa kwisayensi yenhlabathi futhi lisho ungqimba lomhlabathi ongaphezulu, owaziwa nangokuthi umhlabathi ongaphezulu. Lesi sendlalelo sivamise ukuba mnyama ngombala kunezendlalelo eziphansi ngenxa yokunqwabelana kwezinto eziphilayo namaminerali abhekane nesimo sezulu futhi aphulwa emadwaleni ngokuhamba kwesikhathi. Imvamisa iwungqimba lomhlabathi ovunde kakhulu, olunomsoco ophezulu kanye nezinga eliphezulu lezinto eziphilayo. Igama elithi "A horizon" livela egameni lesiJalimane elithi "Auflagehorizont," okusho ukuthi "umkhathizwe wesendlalelo esiphezulu."