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Sediment records from deep-drilling projects such as those carried out by the International Continental Scientific Drilling Program are often tens to hundreds of meters in length. To ensure the complete recovery of a stratigraphic section, a basin is usually cored multiple times in adjacent holes so that gaps between sequential cores, poorly recovered sections, or intervals affected by disturbance can be bridged or replaced with sediments from another hole. Stratigraphic correlation, the alignment of stratigraphically-equivalent horizons in cores from different holes in a common-depth scale, and splice generation, the integration of the most-representative core sections into a composite-stratigraphic section, are essential steps in this process to both evaluate and synthesize the recovered-sediment record and focus the scientific analyses. However, these undertakings can be complex and are inherently subjective, making the need for the development of a single robust stratigraphic section early in the project critical to its success. Despite this, the steps between core recovery and on-splice data generation are rarely published in sufficient detail to allow reconstruction, or refinement, of the composited record at a later date. To increase the transparency of how the composite record is created, and to provide a template for future projects, we detail the step-by-step approaches and decisions involved in generating the composite-depth scale and complete-stratigraphic splice following recovery of sediments from Lake Junín, Peru. We first explain the details and nuances of different drilling-depth scales before describing how we integrated different physical property records to generate the composite-depth scale and complete-stratigraphic splice. Here, we show that due to the complex stratigraphy in the Lake Junín sediments, high-resolution line-scan images of the cores offer millimeter-scale precision for construction of the primary-stratigraphic splice at

Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial–interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles.

Sediment records from deep-drilling projects such as those carried out by the International Continental Scientific Drilling Program are often tens to hundreds of meters in length. To ensure the complete recovery of a stratigraphic section, a basin is usually cored multiple times in adjacent holes so that gaps between sequential cores, poorly recovered sections, or intervals affected by disturbance can be bridged or replaced with sediments from another hole. Stratigraphic correlation, the alignment of stratigraphically-equivalent horizons in cores from different holes in a common-depth scale, and splice generation, the integration of the most-representative core sections into a composite-stratigraphic section, are essential steps in this process to both evaluate and synthesize the recovered-sediment record and focus the scientific analyses. However, these undertakings can be complex and are inherently subjective, making the need for the development of a single robust stratigraphic section early in the project critical to its success. Despite this, the steps between core recovery and on-splice data generation are rarely published in sufficient detail to allow reconstruction, or refinement, of the composited record at a later date. To increase the transparency of how the composite record is created, and to provide a template for future projects, we detail the step-by-step approaches and decisions involved in generating the composite-depth scale and complete-stratigraphic splice following recovery of sediments from Lake Junín, Peru. We first explain the details and nuances of different drilling-depth scales before describing how we integrated different physical property records to generate the composite-depth scale and complete-stratigraphic splice. Here, we show that due to the complex stratigraphy in the Lake Junín sediments, high-resolution line-scan images of the cores offer millimeter-scale precision for construction of the primary-stratigraphic splice at

IODP Expedition 340 successfully drilled a series of sites offshore Montserrat, Martinique and Dominica in the Lesser Antilles from March to April 2012. These are among the few drill sites gathered around volcanic islands, and the first scientific drilling of large and likely tsunamigenic volcanic island-arc landslide deposits. These cores provide evidence and tests of previous hypotheses for the composition and origin of those deposits. Sites U1394, U1399, and U1400 that penetrated landslide deposits recovered exclusively seafloor-sediment, comprising mainly turbidites and hemipelagic deposits, and lacked debris avalanche deposits. This supports the concepts that i/ volcanic debris avalanches tend to stop at the slope break, and ii/ widespread and voluminous failures of pre-existing low-gradient seafloor sediment can be triggered by initial emplacement of material from the volcano. Offshore Martinique (U1399 and 1400), the landslide deposits comprised blocks of parallel strata that were tilted or micro-faulted, sometimes separated by intervals of homogenized sediment (intense shearing), while Site U1394 offshore Montserrat penetrated a flat-lying block of intact strata. The most likely mechanism for generating these large-scale seafloor-sediment failures appears to be propagation of a decollement from proximal areas loaded and incised by a volcanic debris avalanche. These results have implications for the magnitude of tsunami generation. Under some conditions, volcanic island landslide deposits comprised of mainly seafloor sediment will tend to form smaller magnitude tsunamis than equivalent volumes of subaerial block-rich mass flows rapidly entering water. Expedition 340 also successfully drilled sites to access the undisturbed record of eruption fallout layers intercalated with marine sediment which provide an outstanding high-resolution dataset to analyze eruption and landslides cycles, improve understanding of magmatic evolution as well as offshore sedimentatio

East 42nd Street and Park Avenue North. Grand Central Depot, 1890. Grand Central Depot opened in 1871 for the New York and Harlem Railroad and the New Haven Railroad. Architect: John B. Snook in association with engineer Isaac C. Buckhout. Original glass and metal train shed designed by R.G. Hatfield. Snook and Buckhout's designed the depot in the American Second Empire Style using red pressed brick and cast iron trim. The train shed was razed in 1903 when construction for the new Grand Central Terminal began.

Grand Central Depot, East 42nd Street and Park Avenue North, 1890. Grand Central Depot opened in 1871 for the New York and Harlem Railroad and the New Haven Railroad. Architect: John B. Snook in association with engineer Isaac C. Buckhout. Original glass and metal train shed designed by R.G. Hatfield. Snook and Buckhout designed the depot in the American Second Empire Style using red pressed brick and cast iron trim. The train shed was razed in 1903 when construction began for the new Grand Central Terminal.

View looking west along 42nd Street. Grand Central Depot is to the right. Street cars run along the street past the station. Snook and Buckhout's designed the depot in the American Second Empire Style using red pressed brick and cast iron trim. The train shed was razed in 1903 when construction for the new Grand Central Terminal began.

East 42nd Street and Park Avenue North. Grand Central Depot - 1870's. Grand Central Depot opened in 1871 for the New York and Harlem Railroad and the New Haven Railroad. Architect: John B. Snook in association with engineer Isaac C. Buckhout. Original glass and metal train shed designed by R.G. Hatfield. Snook and Buckhout's designed the depot in the American Second Empire Style using red pressed brick and cast iron trim. The train shed was razed in 1903 when construction for the new Grand Central Terminal began.