STUDI URAT KUARSA DAERAH SRIKATON DAN SEKITARNYA, KABUPATEN TANGGAMUS, LAMPUNG

Abstract

ABSTRAK: Pada daerah Srikaton, Kabupaten Tanggamus, Lampung telah dilakukan studi terhadap geometri dan tipe urat kuarsa di batuan andesit Formasi Hulusimpang. Metode yang digunakan dalam studi ini meliputi pengamatan DEMNas (Digital Elevation Model Nasional) dan observasi lapangan berupa pengukuran arah (trend), aperture, spacing yang kemudian dianalisis untuk memperoleh pola umum dan arah gaya yang bekerja pada struktur yang terbentuk. Hasil pengukuran urat kuarsa memiliki aperture 0,1-1 cm, space 0,5-9 cm dan berdasarkan klasifikasi Peacock dkk. (2017), urat kuarsa yang berkembang merupakan tipe extensional dan memiliki geometri pada bagian selatan abutting, isolated, cutting sedangkan kearah utara berkembang geometri cutting dan mutually cutting dengan pola umum urat kuarsa berarah relatif N-S dan arah gaya yang bekerja relatif E-W. Berdasarkan geometri dan tipe urat kuarsa berada pada pergerakan extensional step dibuktikan dari kehadiran intersection damage, linking damage, wall damage, tip damage dan bend damage yang mengindikasikan adanya deformasi pada batuan yang berkembang di daerah fault zone.

Kata Kunci : Urat Kuarsa, Geometri, Extensional, Tanggamus

ABSTRACT: The Srikaton Area, Tanggamus Regency, Lampung Province is the place where we carried out a study about geometry and type of quartz veins in the andesitic rocks of Hulusimpang Formation. The methods which build up this research are DEMNas (National Digital Elevation Model) Observation and also field observation which by measuring the trend, aperture, spacing which then analyzed to obtain the general pattern and also the force direction which act while the structure formed. The result shows that the measurement of quartz vein has the aperture value of 0,1-1 cm, space value of 0,5-9 cm and based on Peacock et al (2017) classification, the formed quartz vein has the type of extensional and it also has the geometry on the southern side are abutting, isolating & cutting while the northern side formed the geometry of cutting and mutually cutting with the general pattern of quartz vein relatively trending N-S with the force direction relatively E-W. Based on the geometry and the type of quartz vein, it is stand in the extensional step movement which proven by the appearance of intersection damage, linking damage, wall damage, tip damage and bend damage which indicates that there area rocks deformation which formed in the fault zone.

Keywords: Quartz Vein, Geometry, Extensional, Tanggamus