Geological Survey of Israel

The GSI conducts surveys and applied scientific research and development, provides advice and services, creates analytical infrastructure, and builds and maintains national databases.[4] Its activities are organized as thematic, short-term, and long-term projects under an annually updated work plan responding to changing state and public needs. The institute is primarily government-funded, with additional support from competitive grants, agreements between Israel and other governments, and national projects. Such projects have included earthquake preparedness and research into the consequences of the declining Dead Sea level.[2]

Ben-Gurion University's research portal classifies the GSI as an external government organization and lists it among institutional partners connected with university research units.[5] The National Library of Israel's Union List identifies a Geological Survey library under the code GSI.[6] The Survey publishes scientific papers, reports, books, and maps, which are available through its library and website.[1] A government portal also provides a searchable listing of scientific papers published from 2016 onward.[7]

The GSI's origins extend to the British Mandate period. After immigrating from Germany in 1924, Professor Leo Picard studied the region's geology, particularly its water resources and minerals.[1] Following the establishment of the State of Israel in 1948, Picard submitted a memorandum proposing an independent geological survey. At that time, the survey operated within the Hebrew University's Department of Geology, which Picard had founded and headed.[1] Picard directed the comprehensive geological survey from 1950 to 1954 and specialized in surveys of petrochemical and water resources and in paleontology.[8]

In 1953, the Geological Survey was separated from the Hebrew University's Department of Geology and became a government institute under the Ministry of Development.[1] Its first independent premises were at St. John's Hospital on Hebron Road in Jerusalem, in a building now incorporated into the Mount Zion Hotel. From 1953 to 1955 it was headed by paleontologist F. Brotzen, a former director of the Swedish Geological Survey.[1] Early departments covered oil, water, geochemistry, paleontology, mineralogy, and mapping. Members of the founding generation included Peretz Grader in oil research, Zeev Shiftan in water, Uri Wurzburger in minerals, and Natan Shalem in Quaternary geology.[1]

Professor Y. K. Bentor led the GSI from 1955 to 1966, when it established itself as an advisory body to the government and government companies dealing with natural resources.[1] The Efraim Katchalski (Katzir) Committee formally recognized it as a research institute in 1968. In 1998, the GSI became an independent organization supervised by the responsible ministry, rather than an integral ministry unit. It moved in 2019 to a purpose-built facility near the Hebrew University's Givat Ram campus.[1]

The Survey's principal scientific periodical, the Bulletin, began publication in 1951. Issues 1–8, published from 1951 to 1955, initially carried the title Publications before the GSI Bulletin designation was adopted.[9] The annual periodical Current Research / Geological Survey of Israel, also cataloged under the Hebrew title Nose mehkar, began publication in Jerusalem in 1981.[10]

The GSI's work developed from early departments devoted to mapping, oil, water, and mineral prospecting into a structure emphasizing engineering and geological hazards, stratigraphy and the subsurface, geology and geochemistry, water resources, and geological mapping.[1] Its practice combines field surveys, laboratory analysis, remote sensing, seismological monitoring, mapping, national archives, databases, and research partnerships. Projects are selected and updated in response to national infrastructure, resource, environmental, and hazard-management needs.[1][2]

Seismology is among the GSI's most operationally significant activities. Its Seismological Division identifies three principal missions: monitoring seismic activity and publishing the seismic catalogue used for risk assessment; alerting the public and emergency responders through the TRUAA Earthquake Early Warning System; and advancing the study of seismology in Israel.[11] During 2021, the division recorded and analyzed 5,267 seismic events, including earthquakes and anthropogenic sources at local, regional, and teleseismic distances.[12]

TRUAA was adapted to Israeli conditions in cooperation with the University of California, Berkeley. It consists of 120 sensors distributed along the Dead Sea Rift and other active fault zones, together with a Jerusalem data-processing center capable of assessing an earthquake's strength and danger within seconds and issuing warnings.[13][14] The network was deployed between 2017 and 2022 and incorporated into the upgraded Israel Seismic Network, which also includes six Cooperating National Facilities and two International Monitoring System sites.[12]

For an earthquake originating at the Dead Sea, TRUAA is estimated to provide approximately three seconds of warning to Jerusalem, 18 seconds to Tel Aviv, and 30 seconds to Haifa. An earthquake of magnitude 6 or higher would trigger a warning for the entire country.[13] Alerts are sent to the Home Front Command, which can notify the public through cellular devices, a dedicated application, alarms, and loudspeaker systems.[13] Analysts use automatic detections as the starting point for manual analysis, and detailed seismic-event information is provided to stakeholders, researchers, and the public.[11]

For the Home Front Command's Turning Point 6 national exercise in 2012, the GSI prepared Earthquake Damage Scenarios in Israel as the Basis for Turning Point 6 National Emergency Drill (GSI Report No. GSI/21/2012, October 2012). The analysis projected the greatest infrastructure damage in northern Israel near the expected epicenter and causative tectonic fault, with damage increasing as infrastructure proximity to the epicenter rose and structural resilience declined.[15][15] The GSI also published a 2016 analytical-empirical study assessing casualty and injury scenarios for a major earthquake affecting Tiberias.[16]

The Survey has additionally published research concerning the recurrence intervals and possible future occurrence of destructive earthquakes in the Jordan Valley and Dead Sea region.[15]

The GSI conducts sustained research on the Dead Sea and the geological hazards associated with its declining water level. As part of the Jerusalem Institute for Policy Research's 2004–2006 Dead Sea Basin project, the Geological Institute was budgeted to monitor the lake continuously and developed instruments intended to locate surface failures in advance so that threatened land uses could be evacuated. The project cited the sinkhole on Route 90 as an example.[17] The GSI is also a partner in a long-term policy initiative established following Government Decision 3742 to develop policy for the Dead Sea basin through 2070.[18]

The GSI collaborated with Technion researchers on an automatic model for detecting sinkholes and other geomorphological phenomena along the Dead Sea coast using airborne laser-scanning data. The model automatically detected approximately 97% of existing sinkholes, including some one meter or less in diameter, with a false-detection rate of 4%. It was intended to support monitoring, hazard assessment, construction restrictions, and infrastructure reinforcement.[19]

To document the relationship between floods and sinkhole formation, the GSI placed a time-lapse camera near Nahal Hever. One day after a January flood, the camera recorded the formation of a sinkhole approximately five meters in diameter.[20] Researchers also used satellite-radar imagery to identify subsidence before a sinkhole appeared near Route 90 and reported that they had warned about that location for approximately two and a half years before the road was closed.[20]

The GSI's Dead Sea Laboratory extended research beneath the water's surface. Using a remotely operated underwater vehicle nicknamed Reuven, researchers examined salt deposits and geological processes on the lakebed without collecting physical samples. Underwater imagery became a key tool for studying the formation of salt layers.[21] In collaboration with the Hebrew University, researchers also measured salt crystallization at different depths and seasons, including along a 55-meter cable. The work found that season, location, and water temperature—not evaporation alone—govern crystallization rates. Salt formed faster in winter than in summer, and the Dead Sea accumulated salt at an average rate of approximately 15 centimeters per year.[22]

The GSI published the 2011 final report of the Red Sea–Dead Sea Water Conveyance Study Program's Dead Sea Study, which examined the physical, chemical, and biological effects of discharging seawater or desalination reject brine into the Dead Sea and its surroundings.[23]

Geological mapping has been a core GSI function since the institute's early years.[1] In 1976, its Mapping Division published the two-volume Inventory of Geological Maps of Israel (Report MM 1/76), which included 16 folded color maps.[24] A geological map of Israel created in 2009 by the GSI and the Survey of Israel under the Ministry of Infrastructures comprised four color sheets, each measuring 60 by 92 centimeters, at a scale of 1:200,000.[25]

A Jewish Virtual Library reference page sourced to the GSI describes seven major groundwater basins: the Coastal, Yarqon-Taninim, Western Galilee, Mount Carmel, Kinneret, Eastern Mountain, and Negev-Arava basins.[26] It characterizes the Negev highland and Arava area as containing three aquifer units: the Early Cretaceous Kurnub Group sandstone aquifer; the Cenomanian-Turonian Judea Group limestone and dolostone aquifer; and the Hazeva Formation and Arava aquifers, composed of Neogene and Quaternary clastic rocks.[26] The Encyclopaedia Judaica bibliography on the geographical survey of the Land of Israel cites a 1960 article in volume 26 of the GSI Bulletin and directs readers to GSI Reports.[27]

The GSI has helped expand scientific knowledge of Israel's offshore environment and energy resources. Together with Israel Oceanographic and Limnological Research and with Ministry of Energy assistance, it participated in a 15-year national project mapping the seabed within Israel's Mediterranean exclusive economic waters. Teams using multibeam sonar across hundreds of survey lines and thousands of kilometers identified submarine hills, dunes, steep terraces, channels, geological faults, and unstable areas. The resulting data were intended to support offshore infrastructure planning and geological-hazard assessment.[28]

A research group led by GSI geologist Zohar Gvirtzman investigated the origin of sand deposits containing natural-gas reservoirs off Israel's coast. In a study published in Nature Geoscience, the researchers combined Mediterranean sediment evidence with research on the Ethiopian Plateau and mantle-circulation models. They concluded that the ancient Nile had transported sediment from East Africa to the Mediterranean for approximately 30 million years, linking deep-Earth processes, Ethiopian uplift, river development, and offshore sediment formation.[29]

A 2016 GSI study sponsored by the Ministry of National Infrastructures, Energy and Water Resources examined Jurassic reservoir potential in the Eastern Mediterranean using drill cores and cuttings from offshore and onshore boreholes.[3] The national PRIME database for documenting and managing petroleum and natural-gas resources was established for operation in cooperation with the GSI and the Geophysical Institute, with the aim of making decades of exploration and production data more accessible.[30] A 1973 publication on petroleum exploration and production in Israel, involving the Survey's Petroleum Division and the Petroleum Commissioner's Office, illustrates the institute's long-standing role in energy-resource documentation.[31]

The GSI has contributed to tsunami-risk assessment for Israel's Mediterranean coast. An A. Salamon study cited in national hazard research, Map of the Regions Liable to be Flooded by a Tsunami along the Mediterranean Shores of Israel in Haifa Bay, the Dan Metropolitan Area, Ashdod, and Ashkelon, was published by the Geological Survey in September 2009.[15] The same national-security assessment recommended that a professional consulting organization such as the GSI examine the probability and consequences of a Mediterranean tsunami.[15]

The GSI converts applied geoscience into tools used in national planning and risk reduction. Its seismic catalogue and TRUAA infrastructure support earthquake-risk assessment and rapid warning, while its damage scenarios contribute to emergency planning.[11][15] Dead Sea monitoring has informed evacuation and construction decisions in areas threatened by sinkholes, and Mediterranean seabed mapping supplies a scientific foundation for evaluating offshore infrastructure routes and geological hazards.[17][28]

The institute's development into an independent research organization supervised by the responsible government ministry strengthened its role in short- and long-term planning. Its laboratories, archives, mapping facilities, seismological systems, and cooperation with universities and other research bodies allow it to combine scientific research with public, industrial, and governmental services.[1]

The GSI's operational role has defined limits. TRUAA is deployed primarily along the Dead Sea Rift and is designed mainly to warn against earthquakes in that zone; it would not be effective for earthquakes originating in the Mediterranean unless connected coastal systems were installed.[13] The GSI is also a specialized scientific contributor rather than the authority with overall responsibility for national earthquake preparedness. That formal responsibility rests with a ministerial committee headed by the defense minister.[32]

Some GSI-related research has challenged earlier scientific models. A study by GSI researcher Amit Segev and colleagues concluded that the eastern Mediterranean formed approximately 150 million years ago rather than the approximately 250 million years proposed by an earlier influential study. The revised age is relevant to models used in gas and oil exploration, although the researchers stated that its implications for the probability of discovering additional energy deposits remained uncertain.[33]