Papua Earthquake Analysis, East-East Active Sesar

JAKARTA - The Geological Agency of the Ministry of Energy and Mineral Resources (ESDM) explained an analysis of the destructive earthquake measuring 5.4 magnitudes that rocked the Papua region.

"Based on the location of the epicenter of the earthquake, depth, and data on the source mechanisms from InaTEWS-BMKG and GFZ Germany, it is estimated that this earthquake will be associated with active fault activity in the east - west direction," said Acting Head of the Geological Agency. Ministry of Energy and Mineral Resources Muhammad Wafid was quoted by ANTARA, Thursday 9 February.

The Geological Agency reports that Jayapura City is close to the location of the earthquake center, which is composed by the morphology of corrugated plateaus and in the south is a bumpy to steep hill.

The area is generally composed by pre-tersier-aged rocks in the form of metamorphic rock, tertiary-aged rock ( sediment rock, limestone), and quarter deposits in the form of coastal deposits, river deposits, and swampy deposits. Some of the pre-tersier and tertiary-aged rocks have weathered.

Endapan kuarter, batu rock berumur pre-tersier dan tertier yang telah mengalami pelapukan pada umumnya bersifat soft, lepas, belum komplek dan memperkuat efek guncangan, sehingga rawan gempa bumi.

On February 9, 2023 at 13.28 WIB or 15.28 WIT, BMKG recorded an earthquake measuring 5.4 magnitudes that rocked the Papua region. The earthquake was centered at 2.60 degrees south latitude, 140.66 degrees east longitude or one kilometer southwest of Jayapura, Papua with a depth of 10 kilometers.

According to data from The United States Geological Survey (USGS) in the United States, the location of the epicenter is located at coordinates 140.557 degrees East Longitude and 2.635 degrees South Latitude with a magnitude of 5.1 at a depth of 22 kilometers.

Meanwhile, based on data from the German Geo Forschungs Zentrum (GFZ), the location of the epicenter was at coordinates 140.63 degrees East Longitude and 2.48 degrees South Latitude with a magnitude of 5.1 at a depth of 10 kilometers.

Previously, on January 2, 2023, the area had also been hit by a destructive earthquake with a magnitude of 5.4 which is 19 kilometers northeast of Jayapura City.

Temporary report from BNPB, the earthquake has resulted in the death of four people (still in data collection) and material losses (a shophouse unit collapsed, one hospital unit was affected, one mosque unit was affected).

According to BMKG data, earthquake shocks were felt in Jayapura City on the V MMI intensity scale (modified mercy intensity).

Data from the Geological Agency revealed that the distribution of residential areas affected by earthquake shocks was located in areas prone to medium to high earthquakes. The earthquake did not cause a tsunami because the epicenter was on land.