GEOLOGI DAERAH AMBARAWA DAN SEKITARNYA, KECAMATAN AMBARAWA, KABUPATEN SEMARANG PROVINSI JAWA TENGAH

Abstract

The geology of the Ambarawa region and its surroundings was chosen as the geological
mapping area because the research area is a natural geological laboratory which is quite
interesting for research. This is because the area is included in the physiography of the Central
Zone/Volcanic Depression Zone, which is genetically formed due to endogenic activities in the
form of tectonics, magmatism, volcanism and exogenic processes are caused by the fact that in
the area there is the Ungaran volcano which is of Quaternary age. On the other hand, much
research has been carried out regarding morphology, lithology, stratigraphy and geological
structure, but is generally based on regional problems. This research was conducted in the
Ambarawa area and its surroundings, Ambarawa District, Semarang Regency, Central Java
Province. This mapping was carried out using a surface mapping method by looking at rock
outcrop data, rock distribution, geomorphology and physical characteristics of rocks. This
concept is called the lithostratigraphic concept. Based on the results of the Geology of the
Research Area, namely: The geomorphology formed in the research area is the volcanic
morphological unit of volcanic slopes, the morphological unit of denudational mountains and
hills, and the fluvial terrace geomorphological unit. Meanwhile, in Regional Geology, the
researcher found 3 rock formations and 1 breakthrough rock and 1 deposit, from the order of

old to young, namely: breccia-andesite lithic arenite rock unit of calliget formation, intrusive-
andesite rock unit, porphyroophanitic andesite rock unit of Gajah mungkur formation, andesite

rock unit Ungaran faneric, and alluvial deposit units. The environmental geology of the
research area which is the source studied is divided into two, namely: positive sources. All land
in the research area is used as agricultural land, livestock and geotourism. A negative source
that was formed in the study area was landslides and some denudational mountainous and hilly
areas, including areas where clean water is difficult.

Keywords : Geomorphology, Geology and Environmental Geology