Amos Frumkin
Amos Frumkin is an Israeli geologist and speleologist. Frumkin (עמוס פרומקין; born in 1953) is a professor of geology at the Hebrew University of Jerusalem. Frumkin was born in Tel Aviv, Israel, in 1953. His expertise is the geology of caves. As an active speleologist, he founded and directs the Cave Research Center of the Hebrew University in Jerusalem. Research. Frumkin's research fields cover karst, cave morphology, environment, and sediments, as indicators of palaeoclimate, palaeohydrology, geological history, tectonics, karst aquifers and human evolution. He also studies underground ancient water supply systems. He uses earth-sciences methods, such  as radiometric dating and stable isotopes, collaborating with archaeologists, biologists and karstologists around the globe. He has authored or co-authored over 100-refereed articles and seven books. Frumkin's Ph.D. thesis on "The karst system of the Mount Sedom salt diapir" focused on karst geomorphology and hydrology of this salt diapir, and its palaeoclimatic implications. This was the first karst research performed in salt. Most of Frumkin's studies are performed on karst terrains in diverse fields of research, comprising palaeoclimate, geomorphology, hydrology, palaeohydrology, geoarchaeology, human impact on the environment and ancient water systems. The research is mostly associated  with underground (speleological) features studied using earth-sciences methods. He studies the underground interface between geoscience, geography, environment, and archaeology. An interdisciplinary and trans-disciplinary view of the sub-surface is achieved by wide-scale interaction and cooperation with scientists in various fields. The research has been performed mainly in Israel, complemented with research in other countries such as Jordan, United Emirates, and Bulgaria. Additional collection of data is done over the globe, resulting in a global karst geomorphology volume. Some of the research is performed in underground laboratories in which measuring equipment was installed. Within an underground laboratory in  Sedom Cave, salt cave speleogenetic processes are monitored for since 1980’s. Much of the data collection is performed by graduate students. Caves are treated as living organisms, with birth (initiation, inception), complex life history involving hydrogeologic, palaeoclimatic, biologic and anthropogenic processes, culminating in cave 'death' during which the cave is obliterated by filling or erosion. All these stages and processes are tackled in Frumkin’s studies. His data and interpretation often changed the previously accepted paradigm, becoming the new, widely accepted 'common knowledge'. For example: (a) Oxygen isotopes fluctuations over glacial/interglacial periods in Levantine speleothems are dominated by  'source effect', consequently glacials were wetter than interglacials (rather than drier as was thought earlier, according to oxygen isotopes); (b) Hypogenic source of the 'Ayyalon salinity anomaly' (rather than an upper source); (c) Salt dissolution as the major undermining source of Dead Sea sinkholes (rather than earlier piping concept); (d) Natural caves have been widely used for refuge in the Mediterranean zone of Israel (rather than only in the desert); (e) Speleothems have been used in Israel in the past for production of 'calcite alabaster' luxury items (rather than only imported from Israel). Karst. Frumkin studies the recharge vadose zone  at the mountains in central Israel, concentrating on recharge through karst shafts and cave drips injecting water and potentially pollution into the aquifer. The integration of recharge over catchment areas is studied using spring monitoring and models. Much of the research is focused in the phreatic, confined and hypogenic parts of the aquifers. It is found that most 's carbonate caves have initiated and developed to full size under such conditions. Aging and dying stages of cave life are studied through excavations in filled caves. Caves preserve unique records of the geological history of their region. They form along structural  lines, they are deformed and uplifted with the rock, and they preserve ancient sediments with geological records. Frumkin studied such features of tectonics, diapir rising rates and morphostructure of the Dead Sea basin and its shoulders. Palaeoclimate. Frumkin has obtained detailed well-dated climatic records for the mid-late Quaternary in Israel. The results solve some important questions on climate change during the Quaternary in the Levant and other regions, and how it could/would influence humans, and the nature of climatic belts migration during glacial/interglacial cycles. The answers obtained have direct impact on understanding present and future climatic  change. The palaeoclimatic studies were extended to lava tubes in Jordan, ancient wood preserved in caves, and to stromatolite caves in the Dead Sea basin. Paleoclimate records were obtained for various climatic regions, from Mt. Hermon, where freezing and thawing periods were reconstructed, through the northern-central Dead Sea catchment, where glacials were shown to be wetter than interglacials. The last interglacial was shown to be extreme in several ways, indicating possible scenarios of future warming. Environmental catastrophes during the Holocene received particular attention, due to their relevance to present and future global change. Geoarchaeology. Among the co-authored studies  are: Dating of early Paleolithic cave inhabitants; evidence for habitual use of fire at the end of the Lower Paleolithic; paleoclimatic corridors for human migration out of Africa; dating ancient Jerusalem water supply system; technical innovations to bring water into ancient cities; Extending the knowledge on Bar-Kokhba Revolt, ~1900 yr ago, through remains including papyrus documents and hoards of coins from caves; Comparing field evidence with historic and archaeologic records. In 2003, Frumkin led a team that radiometrically-dated Siloam Tunnel. He is the author of the generally accepted explanation of how a tunnel dug by two teams working  from opposite ends was engineered by the ancient Israelites before the development of trigonometry. He found for the first time that calcite-alabaster was produced in Israel and not only imported from Egypt.