by Steffen Kutterolf, Mark Brenner, Armin Freundt, Jens Kallmeyer, Sebastian Krastel-Gudegast, Sergei Katsev, Axel Meyer, Liseth Carolina Pérez Alvarado, Juanita Rausch, José Armando Saballos Pérez, Antje Schwalb, Wilfried Reinhard Klaus Strauch

We seek support for a workshop to develop a scientific drilling project in Lakes Nicaragua and Managua, Nicaragua, which are uniquely suited for multidisciplinary, globally important scientific investigation of long, continuous sediment profiles. The region is ideal because of its: 1) long history (>3 Myr) of basin development, 2) past interactions with marine environments, 3) proximity to the volcanic arc, 4) significance as an endemic hot spot, 5) strategic location to study the great American biotic interchange, 6) the recently initiated Caribbean to Pacific canal construction via Lake Nicaragua, and 7) the interactive combination of seismological, volcanological, paleoclimatological, paleoecological, and paleoenvironmental studies. The first seismic pre-site survey confirms a drillable long and continuous sediment record suitable for initial drill site selection that will be supplemented by additional seismic profiles and shallow drilling after workshop funding is obtained. The workshop will serve to define and complement scientific objectives of the drilling project proposal. It will address topics such as (a) development of a Neotropical environmental and paleoclimate record that will extend presently available late Pleistocene-Holocene records back to Tertiary times, (b) determination of the times and rates of marine transgressions and regressions, their tectonic and climatic controls and ecological consequences, (c) investigation of recurrence rates and magnitudes of natural hazards such as explosive volcanic eruptions, landslides, earthquakes and hurricanes, (d) constraints on the timing and magmatic compositional changes during shifts of the volcanic arc, (e) linkages between long-term terrestrial and marine environmental records, and (f) correlation of climatic, geologic and (Holocene) anthropogenic influences on biodiversity and limnological variables. Investigating these topics using drill cores will have global scientific impacts and yield regional socio-economic benefits. The proposed drilling project has the potential for future expansion to a complementary IODP project targeting the structurally related offshore Sandino Basin. All data will be accessible to Nicaraguan authorities, which will improve assessments of natural and man-made hazards and risks. The project will improve recognition of Nicaragua’s natural resources and will create opportunities for project-related outreach activities and exchange programs between research, educational, and governmental institutions in Nicaragua and other participating countries. The proposed workshop will foster collaborative interactions and refine scientific hypotheses to be tested by drilling and associated investigations in the Nicaraguan lakes under the broad umbrella of Paleoclimate, Paleoenvironment, and Paleoecology, thereby contributing to three major societal challenges addressed by ICDP: Climate & Ecosystems, Deep biosphere, and Natural Hazards.

• Long, continuous sediment cores from multiple sites in Lakes Managua and Nicaragua will provide a unique archive of past tropical climate and environmental changes extending back > 3Ma, representing the oldest lacustrine record in continental Neotropics. Data from the cores will also shed light on physical limnological changes, earthquake, volcanic eruption, and flank collapse magnitudes and frequencies as well as the processes leading up to these natural hazards and their consequent socio-economic impacts. The seismic imaging surveys to be performed in preparation of the project will yield data on both, long-term basin development, and the deeper structure of western Nicaragua, which is next to the documentation of biological, physical, and chemical conditions of the lakes relevant to the canal construction. The resulting record of long-term paleoclimate variability will help to:
• - Predict future climate scenarios and guide future agricultural strategies in Nicaragua and other tropical regions - Link past climate shifts to terrestrial paleoenvironmental and paleoecological changes - Track moisture availability/origin in the region for selected time periods (e.g. LGM), which is still unclear, as well as generate information on climate modulations/forcings (Atlantic vs. Pacific) and ITCZ dynamics and migrations - Determine the frequency and magnitude of past natural hazards (volcanic eruptions, earthquakes, large landslides, hurricanes) - Evaluate environmental changes that resulted from natural drivers (e.g. climate change and tectonic movements) and from human influences (deforestation, agriculture, urbanization, pollution). Evaluating past freshwater/saltwater phases initiated by tectonics, and respective influence on micro- and macrobiota will be essential to predict consequences of future changes (e.g. from canal construction).

Central America, Hazards, Lake Drilling, Nica-Bridge, Nicaragua, Paleoclimate, Paleoecology, Paleoenvironment

Latitude: 11.61667, Longitude: -85.35000