ered only 0.86 m (3%). We switched back to the HLAPC system, and Cores 13F-17F penetrated 19.6 m of formation (68.4–88.0 m CSF-A) and recovered 20.03 m (102%). Because we wanted to core deeply at this site, the formation appeared soft enough, and the HLAPC takes longer, we switched back to the APC. Cores 18H-21H extended from 88.0 to 113.4 m DSF and recovered 25.02 m of core (99%); however, all but the first were only partial strokes (7.6, 4.9, and 3.4 m) and were advanced by recovery.

We switched to the HLAPC, and Cores 22F-31F penetrated 43.1 m (113.4–156.5 m DSF) and recovered 45.33 m; the last two were only partial strokes. As the formation still appeared to be too firm for full APC coring and achieving our primary objective of obtaining deeper samples would take much longer with the HLAPC, we deployed the XCB coring system. Cores 32X-36X penetrated 48.5 m (156.5–205.0 m CSF-A) but only recovered 1.17 m of sediment (2%). We then switched back to APC coring, first with HLAPC Core 37F, which penetrated from 205.0 to 209.7 m DSF and recovered 4.79 m (102%). The final core of Hole U1449 was another attempt at APC Core 38H that only partially stroked out from 209.7 to 213.5 m CSF-A and recovered 3.87 m of core.

Because we (1) had achieved a substantial part of this site's objectives, (2) had exceeded the operational time allocated for this site, and (3) had many high-priority expedition objectives remaining, we decided to not to spend any more time attempting to sample to the full 300 m originally planned.

The APC system penetrated a total of 57.1 m of formation and recovered 52.37 m (91%, but includes advance by recovery and one core that did not penetrate the formation). The HLAPC system penetrated 71.9 m of formation and recovered 74.98 m (104%). The XCB system penetrated a total of 83.5 m of formation and recovered only 2.03 m (2%). Ten barrels of sepiolite mud was circulated during or shortly after cutting Cores 10X and 33X.

## Hole U1449B

After finishing coring in Hole U1449A, we offset the ship 20 m east and obtained a single mudline core in Hole U1449B for high-resolution microbiological and geochemical sampling. The bit was spaced out to 3661.0 m DRF in an attempt to recover approximately 7.0 m with the mudline core. Core 1H extended from the seafloor to 7.9 mbsf. We then retrieved the drill string, secured the rig floor, and started the short transit to Site U1450 at 1530 h on 10 February.

## Site U1450

Site U1450 (proposed Site MBF-2A) consists of two holes. Hole U1450A (10–17 February 2015) was cored to 687.4 mbsf using primarily the HLAPC system alternating with short (4.8 m) advances without coring. The APC and XCB systems were used in the shallow and deepest portions of the hole, respectively. Hole U1450B (7–11 March) was drilled without coring to 608.0 mbsf and RCB cored continuously from there to 811.9 mbsf, and then downhole logging was attempted.

## Hole U1450A

After the short 26 nmi transit from Site U1449, we arrived at Site U1450 at 1830 h on 10 February and lowered the bit to the seafloor. We spudded Hole U1450A at 0255 h on 11 February, and the mudline core established the seafloor at 3655.3 mbl. This hole was drilled to a total depth of 687.4 mbsf using a combination of coring (APC, HLAPC, and XCB systems) and short (mostly 4.8 m) advances without coring. Nonmagnetic core barrels were used for all APC and HLAPC cores, and the nonmagnetic drill collar was in the BHA.

We used the APC system for the first three cores (1H-3H, 0–11.7 m DSF; 20.2 m cored; 18.63 m recovered). Because the latter two cores were partial strokes, we switched to the HLAPC system. Cores 4F-8F extended from 20.2 to 43.7 m DSF with a range of recoveries (0%–72%); despite this change we did not advance by recovery but rather the full 4.7 m barrel length each core.

From 43.7 to 132.9 m DSF (after Core 8F to Core 27F), we took a series of HLAPC cores interspersed with six 4.8 m long advances without coring. These HLAPC cores were taken consecutively when fine-grained intervals (e.g., without sand/silt) were encountered. Two cores with the APC system (Cores 22H and 24H) were taken in this section, but these recovered only 3.35 m of sediment. These were the only two cores where core orientation was attempted.

Based on our experiences in the upper portion of this hole and at Site U1449, we decided to deepen the hole by an alternating series of 4.7 m long HLAPC cores followed by 4.8 m advances without coring. The full APC coring system could not sufficiently penetrate/recover this formation, and the XCB system, although it could penetrate it, would not recover core from this type of formation. In addition, the science objectives required deep penetration sampling at multiple sites, which could not be accomplished in time if the HLAPC was used continuously. This alternating pattern penetrated 428.4 m of formation from 132.9 to 561.3 m DSF (Cores 28F-119F). The only exception to this pattern occurred in a few intervals where HLAPC cores were taken consecutively (Cores 80F-84F, 114F, 115F, and 117F-119F). The HLAPC cores taken from this interval (Cores 28F-119F) penetrated 226.8 m of formation and recovered 176.7 m of core (77%). Forty-two 4.8 m advances without coring penetrated 201.6 m of formation.

Because we had some difficulty getting Core 119F to penetrate the formation, we cored the rest of the hole with the XCB system, except for five HLAPC cores and three 4.8 m advances without coring. Cores 120X-123X cored 37.7 m (561.3–599.0 mbsf) and recovered 8.89 m (24%). Because the penetration rate substantially increased while cutting the last part of Core 123X, we inferred that the formation had likely changed back to sand. We switched back to HLAPC coring, as it was the most likely system to be able to recover sands. We then cored an alternating series of HLAPC cores (124F, 126F, and 128F) and 4.8 m advances without coring that penetrated 11.2 m of formation and recovered 8.89 m (85%).

The lowermost section of the hole consisted of mostly of XCB cores, with two HLAPC cores. Cores 129X and 132X-136X (619.8–628.2 and 637.7–686.3 mbsf) penetrated 57.0 m and recovered 6.47 m of core (11%). Two HLAPC cores (130F and 137F; 628.2–632.9 and 686.3–687.4 mbsf) penetrated 5.8 m and recovered 4.05 m (70%). The deepest core in this hole (HLAPC Core 137F) set the record for the deepest penetration piston core in scientific ocean drilling.

We decided to terminate operations in Hole U1450A after this last HLAPC core. We felt that recovering core to the 900 m target objective and obtaining good wireline logs would be better achieved by drilling a new RCB hole at this site later in the expedition. We pulled the drill string out of Hole U1450A, and the bit cleared the seafloor at 2035 h on 16 February and was back on the rig floor at 0235 h the next day. After the drill floor was secured and the thrusters raised, we started the transit to Site U1451 at 0418 h on 17 February.

Five APCT-3 formation temperature measurements were conducted in Hole U1450A at 86.3, 118.7, 156.6, 175.6, and 318.1 m DSF (while taking Cores 17F, 24H, 32F, 36F, and 66F, respectively).
The last of these measurements is the deepest APC formation temperature measurement ever obtained.

In Hole U1450A, we cored a total of 444.7 m and recovered 282.73 m of core (64%). This included 71 HLAPC cores (318.3 m cored; 245.39 m recovered; 77%), 5 APC cores (31.7 m cored; 21.98 m recovered; 69%), and 10 XCB cores (94.7 m cored; 15.36 m recovered; 16%).

## Hole U1450B

After a 64 nm transit from Site U1451, we arrived back at Site U1450 at 1342 h on 7 March. Hole U1450A was cored to 687.4 mbsf, so we decided to drill without coring to 608 m and then RCB core below that depth and attempt to log the hole. This RCB coring has a 79.4 m overlap with the deepest cores from Hole U1450A. We assembled an RCB with a mechanical bit release (MBR), lowered it to the seafloor, and started drilling in Hole U1450B at 2305 h on 7 March. We continued drilling without coring in Hole U1450B from 0 to 465.0 mbsf. At this point (1945 h on 8 March), the low penetration rate led us to retrieve the center bit for inspection. No problems were observed. The center bit was redeployed, and drilling resumed at 2100 h on 8 March. At 0414 h on 9 March, the bit reached 608.0 m. After retrieving the center bit, RCB coring started at 0515 h on 9 March. Nonmagnetic core barrels were used for all RCB cores. Cores 2R-11R penetrated from 608.0 to 705.1 mbsf (97.1 m) and recovered 15.77 m of core. Because of poor recovery for Cores 3R-6R (3.72 m; 8%), a slow penetration rate, and sediment jammed in the core catchers, we ran a bit deplugger after Core 6R to clear the bit. After the bit deplugger was recovered, Cores 12R-22R penetrated from 705.1 to 811.9 mbsf (106.8 m) and recovered 15.77 m of core (29%). RCB coring in Hole U1450B sampled 203.9 m of formation (608.0-811.9 mbsf) and recovered 46.66 m of sediment (23%).

After the last core arrived on deck (1715 h on 10 March), we decided our primary coring objectives had been mostly achieved, so we prepared the hole for downhole logging. We circulated 35 barrels of mud to clear cuttings out of the hole (before retrieving the last core), deployed the rotary shifting tool (RST) to release the bit in the bottom of the hole, filled the hole with weighted mud, and raised the bottom of the drill string to 82.7 m. At 2300 h, we started assembling the first logging tool string (triple combo). We finished assembling and testing the triple combo at 0115 h on 11 March. We lowered it through the drill string and out of the open end of the drill string at 82.7 mbsf. The bottom of the tool string encountered an obstruction in the hole at 133.7 mbsf. The tool string was raised and lowered a few times in an attempt to pass through this obstruction, but the tool became stuck in the hole. After applying the maximum amount of force to the logging wireline, the tool string was freed from the formation. The tool string was recovered on the rig floor at 0615 h on 11 March. We decided logging was not possible because of the hole conditions. After the rig floor was cleared of the logging setup, the driller started to pull the string out of the seafloor. However, the pipe had become stuck, and the drillers had to apply 40,000 lb of overpull to extract the BHA out of the seafloor. After the drill string was retrieved, the rig floor secured, the thrusters raised, and the seafloor positioning beacon recovered, we departed for Site U1452 at 1430 h on 11 March.

## Site U1451

We drilled two holes at Site U1451 (proposed Site MBF-3A). Hole U1451A extended from the seafloor to 582.1 m DSF and was advanced by the APC, HLAPC, and XCB systems, as well as short (4.8 m) intervals drilled without coring. A reentry cone with 401.76

m of 10% inch casing was installed in Hole U1451B and then was cored with both the XCB and RCB systems to a total depth of 1181.3 m DSF. Unfavorable hole conditions in Hole U1451B precluded collecting wireline log data.

## Hole U1451A

After the 64 nm transit from Site U1450, we arrived at Site U1451 at 1018 h on 17 February 2015. We assembled the APC/XCB BHA, lowered it to the seafloor, and started coring in Hole U1451A at 1810 h. Cores 1H-9H extended to 55.6 mbsf and were advanced by recovery; they were also oriented. The last of these cores recovered only 3.3 m, so we switched to HLAPC cores. Cores 10F-21F extended from 55.6 to 112.0 mbsf (56.4 m) and recovered 58.78 m of core (104%).

Based on the nature of the core material recovered, we decided to switch back to APC coring. Cores 22H-30H extended from 112.0 to 197.5 mbsf (85.5 m) and recovered 73.99 m of core (74%). Each of these cores was not advanced by recovery but by the full 9.5 m barrel length. Core orientation was conducted on Cores 23H-30H. The core liner of the last two APC cores failed, so we switched back to the HLAPC system.

The hole was then deepened from 197.5 to 573.7 mbsf with an alternating series of HLAPC cores and 4.8 m advances without coring. The 41 HLAPC cores from this interval (31F-110F) cored 189.0 m and recovered 144.3 m (76%); thirty-nine 4.8 m long intervals were drilled without coring. The majority of the HLAPC cores in this section were partial strokes. Recovery for the last four HLAPC cores was poor (only 0.55-1.30 m), and up to 40,000 lb was required to pull the core barrel out of the formation, despite only having penetrated a short distance into the formation. We decided further HLAPC coring would not work. Before stopping coring operations in Hole U1451A, we took one XCB core (111X; 573.7-582.1 mbsf; 4.75 m recovered; 57%). After this last core from Hole U1451A arrived on deck at 1750 h on 21 February, we started pulling the drill string out of the hole. The bit cleared the seafloor at 2130 h on 21 February. After taking a break from tripping pipe to slip and cut the drill line, we continued to retrieve the drill string, and the bit arrived back on the rig floor at 0600 h on 22 February.

Formation temperature measurements (APCT-3) were made while taking Cores 4H, 7H, 10H, 13H 29H, 52F, and 74F (28.9, 46.3, 60.3, 74.4, 188.0, 301.9, and 406.4 mbsf, respectively). The latter of these broke the record for the deepest piston core formation temperature measurement ever obtained. The previous record was set at our last site.

We cored 394.9 m in Hole U1451A and recovered 337.80 m of core (86%). The breakdown by coring system is as follows:

* 18 APC cores penetrated 141.1 m and recovered 129.96 m of core (92%).

* 53 HLAPC cores penetrated 245.4 m and recovered 203.1 m of core (83%).

* 1 XCB core penetrated 8.4 m and recovered 4.75 m of core (57%).

* Thirty-nine 4.8 m long intervals were drilled without coring for a total length of 187.2 m.

## Hole U1451B

After finishing Hole U1451A, we started preparing and assembling the Hole U1451B reentry system to facilitate our deep coring and logging objectives at this site. The preassembled reentry cone was moved over the moonpool, and 401.75 m of 10% inch casing was assembled and latched into the reentry cone. To drill this casing
into the seafloor with a bit and underreamer, we made up a drilling assembly consisting of a 9⅜ inch tricone bit, an underreamer set to 12¾ inches, a mud motor, two stands of drill collars, and 328.57 m of drill pipe. The casing running tool was attached to the top of the drilling assembly and then latched into the reentry system. At 0315 h on 23 February, we opened up the moonpool and started lowering the reentry system to the seafloor. After deploying the camera system at 1000 h, we started to drill the reentry system into the seafloor at 1205 h.

At 0430 h on 24 February, we finished drilling in the 401.76 m of 10¾ inch casing with the reentry cone. The reentry cone landed on the mound of cuttings from drilling the hole ~1 m above the seafloor. The bottom of the casing was at ~400.76 mbsf. The casing running tool was detached from the reentry system, and we started to retrieve the camera system and drilling assembly. By 1600 h on 24 February, all parts of the drilling assembly had arrived back on the rig floor and been taken apart, cleaned, and stored. We assembled an APC/XCB BHA with a 9⅜ inch polycrystalline diamond compact (PDC) bit and started lowering it to seafloor at 1830 h on 24 February. We planned to drill without coring to ~540 mbsf (Hole U1451A was cored to 582.1 mbsf) and then XCB core as far as possible. We decided on the APC/XCB system so we had the option to deploy the APC to recover any loose sands, a high-priority science objective, not likely to be recovered by our other coring systems (XCB/RCB).

We reentered Hole U1451B at 0255 h on 25 February, retrieved the camera system, lowered the bit to 396 mbsf (~5 m above the bottom of the casing), dropped a center bit, and then washed to 404.7 mbsf. At 0645 h on 25 February, we started drilling ahead without coring from that depth to 542 mbsf; the previous hole was cored to 582.1 mbsf and we wanted to attempt to recover core from this overlapping interval. We retrieved the center bit and started XCB coring. Eleven XCB cores and a single 6.7 m interval drilled without coring penetrated from 542.0 to 640.8 mbsf (98.8 m). Cores 2X-13X sampled 92.1 m and recovered 19.05 m of core (21%).

Several XCB cutting shoe failures occurred while coring. When Core 7X arrived back on the rig floor, the lower part of the XCB cutting shoe was missing; it had been left in the hole. The inner flow diverter was still in place, so we inferred that the bit became overheated and failed after coring as the bit was pulled off the bottom of the hole. We deployed an XCB barrel with a center bit, advanced 6.7 m to push the pieces of the broken XCB bit out of the path of our coring bit, and then resumed XCB coring (Cores 9X-12X). On the last of these cores (12X), the XCB cutting shoe was recovered with substantial cracks in it; it fell apart on deck when the core was hydraulically extracted from the throat of the cutting shoe. Once again, we inferred that the bit was overheating. For the next core, we decided to reduce the weight on the bit, lower the rotation rate, and increase the fluid being pumped. However, while cutting Core 13X the penetration was substantially reduced, so we retrieved it after only a 3 m advance. When Core 13X was recovered on the rig floor, the lowermost part of the XCB cutting shoe was missing, and we decided that XCB coring was no longer viable. At 1930 h on 26 February, we started pulling out of the hole so we could switch to an RCB coring assembly, reenter Hole U1451B, and continue coring to our target depth.

After the APC/XCB bit arrived back on the rig floor (0340 h on 27 February), we started assembling an RCB bit and BHA. After the bit was spaced out, we picked up three additional drill collars, finished assembling the BHA, and started lowering it to the seafloor at 0800 h on 27 February. We deployed the camera and reentered Hole U1451B at 1642 h. The bit was lowered through the 10¾ inch cas-

ing that extends to 400.76 mbsf and then into the open hole below. At 578 mbsf, the bit encountered an obstruction in the hole, so it was raised up to 569 mbsf to install the top drive. At this time, the drill string became stuck in the hole. The drill string was freed after 2 h of working the drill string by applying overpull, torque, and circulation. We raised the bit back up to 549 mbsf, installed two knobs beneath the top drive, and started washing and reaming back to the bottom of the hole (640.8 mbsf). After reaching the bottom of the hole, we drilled ahead 5 m (640.8-645.8 mbsf) with a center bit to ensure any pieces of the failed XCB cutting shoe were cleared to the side of the hole. Two wireline runs were needed to retrieve the center bit, as the first run came up without the core barrel and center bit. We started RCB coring at 0645 h on 28 February.

Cores 15R-36R penetrated from 645.8 to 860.2 mbsf (214.4 m) and recovered 49.51 m of core (23%). The drill string became stuck after retrieving Core 35R, and 30 min was needed to work the pipe free. Because of poor hole conditions, we decided to conduct a wiper trip after Core 36R arrived on the rig floor. While raising the bit back up into the 10¾ inch casing that extends to 401 mbsf, the drill string encountered significant torque and up to 30,000-40,000 lb of drag. After slipping and cutting the drill line with the bit inside the casing, the bit was lowered to 637 mbsf, where it encountered a bridge. We washed and reamed from this depth back down to the bottom of the hole (860.2 mbsf) and resumed RCB coring at 0145 h on 3 March. After a few fast-penetration, low-recovery cores (Cores 38R-41R; presumably loose sands) with high drill string torque and some overpull, we conducted a short wiper trip by raising the bit from 908.9 to 869.6 mbsf and then washing back to bottom. RCB coring resumed at 1115 h on 3 March.

Cores 42R-73R cored from 908.9 to 1181.3 mbsf (272.4 m) and recovered 104.28 m of core (38%). Because of the nature of the rocks being recovered, we decided to stop further coring at 1440 h on 6 March and conduct wireline logging. We started to raise the bit back up to the base of the 10¾ inch casing (401 m), two joints of drill pipe at a time (doubles) with the top drive in place, because of the poor hole conditions. While raising the bit, the drill string experienced torque and overpull and then became stuck at 963 mbsf. We also observed up to 250 psi of overpressure in the drill pipe. After the drill string was freed, we had to rotate, apply overpull, and circulate to be able to raise the bit up to 529 mbsf. We then removed the top drive but still had 20,000-25,000 lb of overpull until the bit was up inside the casing. Based on hole conditions, we decided it was not reasonable to log the hole. At the end of 6 March, we started reassembling the drill pipe doubles back into stands so that we could resume recovery of the drill string. After the bit was back on board, the rig floor was secured, and the seafloor positioning beacon was recovered, we departed for Site U1450 at 0806 h on 7 March.

## Site U1452

Three holes were cored at Site U1452 (proposed Site MBF-5A). Hole U1452A was a single mudline core for high-resolution studies around the Toba ash layer. Hole U1452B penetrated a total of 217.7 m; 174.5 m of this interval was cored and 140.33 m of core was recovered (64%). Hole U1452C was continuously cored from the seafloor to 41.3 mbsf to obtain a more complete sampling of the uppermost levee sequence.

## Hole U1452A

After a 29 nmi transit, we arrived at Site U1452 at 1700 h on 11 March 2015, prepared an APC/XCB BHA, and lowered it to the sea-
floor. After lowering the drill string to the seafloor, we attempted to take the mudline APC core in Hole U1452A at 0315 h on 12 March, but the system would not fire (shear pins did not fail). After recovering the APC core barrel and diagnosing/fixing the problem, we re-deployed the APC core barrel and started coring Hole U1452A at 0540 h on 12 March. Core 1H penetrated 8 m. This core is dedicated to high-resolution studies around the Toba ash layer, so it was only run through the whole-round logging systems and then stored for postexpedition splitting and sampling. Nonmagnetic hardware (drill collar and core barrels) was used for all APC and HLAPC cores at Site U1452.

## Hole U1452B

We then offset the ship 20 m east and started coring Hole U1452B at 0700 h on 12 March. Cores 1H-5H penetrated to 41.4 mbsf and recovered 33.51 m of sediment (80%). All of these cores were oriented. Core 5H was a partial stroke and inferred to have only penetrated ~4.7 m based on the amount of competent material recovered in the top of the core. We then switched to the HLAPC system. Cores 6F-12F penetrated from 41.4 to 71.1 mbsf (29.7 m) and recovered 23.32 m of core (79%). Based on evidence on the outside of the core barrel (rusty steel scrubbed clean by the formation), Core 6F only penetrated 1.5 m into the formation, so it was advanced this amount; all other cores were advanced 4.7 m. From 71.1 to 142.4 mbsf, we started alternating 4.7 m long HLAPC cores with 4.8 m intervals drilled without coring. In this interval, seven HLAPC cores (14F-26F) penetrated 32.9 m and recovered 21.41 m of core (65%). The eight 4.8 m advances without coring penetrated 38.4 m. Nearly continuous HLAPC coring (Cores 28F-43F, except for a single 4.8 m advance without coring) penetrated from 142.4 to 217.7 mbsf and recovered 62.49 m of core (89%). Although we had originally planned to core to 300 mbsf, we decided our primary coring objectives at this site had been achieved. We pulled out of Hole U1452B, and the bit cleared the seafloor at 0030 h on 14 March. Hole U1452B penetrated a total of 217.7 m; 174.5 m of this interval was cored and 140.33 m of core was recovered (64%). The majority of cores were partial strokes.

## Hole U1452C

After the ship was offset 20 m south of Hole U1452B, Hole U1452C was continuously cored from the seafloor to 41.3 mbsf to obtain a more complete sampling of the uppermost levee sequence. APC coring in Hole U1452C started at 0245 h on 14 March. After a successful mudline core (1H), we used the XCB system to core from 7.0 to 11.0 mbsf; in Hole U1452B, this interval had poor recovery and appeared to be a hard layer. Unfortunately, this core came back empty. APC coring resumed and Cores 3H-6H extended from 11.0 to 41.3 mbsf (30.3 m) and recovered 30.3 m of core (87%). All APC cores were oriented. When the last core recovered sand, our objective for this hole was reached (we had passed below the targeted levee section), so we pulled out of the hole and recovered the drill string. After the bit was back on board, we secured the rig floor, raised the thrusters, and departed for Site U1453 at 1900 h on 14 March.

## Site U1453

At Site U1453 (proposed Site MBF-4A), we cored with the APC and HLAPC systems to 215.7 mbsf. In this interval, 37 cores penetrated 186.7 m and recovered 164.78 m of sediment (88%). Six short (4.8 or 5.0 m) intervals were advanced without coring. After coring was completed, we collected downhole logging data with two tool

strings (triple combo and FMS-sonic). Logging was very successful with good hole conditions and reached the full depth of the hole.

## Hole U1453A

After a short 23 nmi transit, we arrived at Site U1453 at 2145 h on 14 March 2015. We assembled an APC coring BHA and lowered it to the seafloor. We used an 9.875 inch PDC coring bit with a lockable float valve (LFV) so that we would have a smaller diameter hole for improved log data if hole conditions would allow. Nonmagnetic hardware was used for all cores (drill collar and core barrels). We finished lowering the drill string to the seafloor and started coring in Hole U1453A at 1020 h on 15 March. Except for one 5 m interval advanced without coring, APC and HLAPC coring penetrated from the seafloor to 172.9 mbsf (Cores 1H-34F) and recovered 148.84 m of core (89%). The HLAPC system was used for all cores except for the first four cores (1H-4H) and one deeper core (29H; 142.4-149.4 mbsf) that targeted a hemipelagic layer; these were cored with the APC system. The rest of the coring in Hole U1453A (172.9-215.7 mbsf) consisted of four HLAPC cores alternating with five 4.8 m advances without coring. Cores 36F-42F penetrated 18.8 m and recovered 15.94 m of sediment (85%). The majority of piston cores at this site were partial strokes. Orientation was attempted on all of the APC cores.

After the primary coring objectives were achieved, at 0715 h on 17 March we started preparing the hole for downhole logging. We circulated 25 barrels of mud to clean cuttings out of the hole. To ensure the LFV was functioning properly for logging, we also activated it with a go-devil and an XCB barrel. After filling the hole with 180 barrels of 12.0 lb/gal mud, we raised the bit up to logging depth (78.5 mbsf). The triple combo logging string was assembled, and we began lowering it down the drill string at 1200 h on 17 March. At ~2170 m DRF with the drill pipe well above the seafloor, the string began losing weight. We inferred it had encountered the weighted mud, so we circulated the mud down to the seafloor and resumed lowering the logging tool string. Log data were collected to the full depth of the hole and indicated good hole conditions. After the triple combo was recovered, we ran the FMS-sonic tool string, which also reached the bottom of the hole. The tool string was back on the rig floor just before midnight on 17 March, and the rig floor was cleared of all equipment by 0055 on 18 March. It took us ~45 min to free the pipe from the formation, and the bit cleared the seafloor at 0200 h. We retrieved the drill string, secured the rig floor, raised the thrusters, and departed for Site U1454 at 1130 h on 18 March.

## Site U1454

We cored four holes at Site U1454 (proposed Site MBF-7A). Hole U1454A was a single mudline core to 7.5 mbsf for microbiology and geochemical studies. Hole U1454B was cored with the APC and HLAPC systems to 161.8 mbsf and recovered 129.51 m of sediment (88%). This hole also included three 4.8 m advances without coring. Holes U1454C and U1454D were shallow penetrations (37.2 and 37.1 mbsf, respectively) and recovered 30.16 and 24.46 m of sediment (81% and 66%), respectively. Core orientation was attempted for all APC cores, nonmagnetic hardware was used, and many of the cores were only partial strokes.

## Hole U1454A

After a 56 nmi transit, we arrived at Site U1454 at 1706 h on 18 March 2015, assembled an APC/XCB BHA, and lowered it to the seafloor. At 0115 h on 19 March, we took a single mudline core in Hole U1454A (1H; 0-7.5 mbsf) for microbiologic and geochemical studies.
## Hole U1454B

We offset the ship 20 m east and started coring in Hole U1454B at 0255 h on 19 March. The APC penetrated from the seafloor to 32.1 mbsf (Cores 1H-4H; 30.28 m recovered; 94%). We switched to the HLAPC and cored from 32.1 to 161.8 mbsf. This 129.7 m interval included three 4.8 m advances without coring. Cores 5F-32F sampled 129.7 m of formation and recovered 99.23 m of sediment (86%). Coring was interrupted for 2 h (1400-1600 h on 19 March) when a broken strand on the coring line snagged in the top drive; ~1500 m of coring line had to be cut off and the coring line retermi-nated. A single temperature measurement was obtained while recovering Core 30F.

## Holes U1454C and U1454D

Having achieved our depth objectives, we decided to core two more holes to obtain a more complete section in the upper ~37 m. We pulled the bit out of Hole U1454B, offset the ship 20 m south, and started coring in Hole U1454C at 1650 h on 20 March. Cores 1H-6F penetrated to 37.2 mbsf and recovered 30.16 m (81%). We pulled the bit out of Hole U1454C, offset the ship 20 m west, and started coring in Hole U1454D at 0020 h on 21 March. Cores 1H-5F penetrated to 37.1 mbsf and recovered 24.46 m (66%). We pulled the bit out of the seafloor (0630 h) and retrieved the drill string. Once the bit was back on the rig floor, we secured the rig floor, raised the thrusters, and departed for Site U1455 at 1336 h.

## Site U1455

We cored three holes at Site U1455 (proposed Site MBF-1A; DSDP Site 218). Holes U1455A and U1455B each consisted of single mudline core penetrating to 0.9 and 6.9 mbsf, respectively. Hole U1455C consisted of coring in three intervals: from 0 to 122.3 mbsf (APC and HLAPC), from 359.8 to 431.4 mbsf (HLAPC), and from 773.0 to 949.0 m (RCB). The uppermost interval consisted of APC and HLAPC coring and four 4.8 m advances without coring (19.2 m). Cores 1H-24F cored 103.1 m in this interval and recovered 89.82 m of sediment (87%). We drilled 237.5 m without coring from 122.3 to 359.8 mbsf and then resumed continuous HLAPC coring. Cores 26F-41F penetrated from 359.8 to 431.4 mbsf (71.6 m) and recovered 48.82 m of sediment (68%). After retrieving the drill string to switch to the RCB system, we reentered Hole U1455C and drilled ahead without coring from 431.4 to 773.0 mbsf. We RCB cored from that depth to 949.0 mbsf. Cores 43R-60R penetrated 176.0 m and recovered 59.36 m of sediment (34%). Coring ended when the operational time for the expedition expired.

## Hole U1455A

After the 26 nmi transit, we arrived at Site U1455 at 1640 h on 21 March. We assembled an APC BHA with a 9⅞ inch PDC bit and a LFV (in case logging became an option) and lowered it to the seafloor. Coring in Hole U1455A started at 0105 h on 22 March. This hole was intended to be a single mudline core for microbiologic and geochemical studies. Because Core 1H recovered only 0.9 m, we decided to offset the ship and start another hole.

## Hole U1455B

After the ship was offset 20 m east, coring started in Hole U1455B at 0225 h on 22 March. Core 1H recovered 6.88 m and was considered sufficient for microbiologic and geochemical studies.

## Hole U1455C

We offset the ship 20 m south and started coring in Hole U1455C at 0350 h on 22 March. Cores 1H-3H penetrated from the seafloor to 23.2 mbsf and recovered 22.42 m of sediment (97%). Because Core 3H was only a partial stroke and the core liner cracked, we switched to the HLAPC system. The hole was deepened to 122.2 mbsf with 17 HLAPC cores and four 4.8 m advances without coring. Cores 1H-24F cored 103.1 m in this interval and recovered 89.82 m of sediment (87%). We then drilled from 122.3 to 359.8 mbsf (237.5 m) without coring; this lasted from 0230 to 1345 h on 23 March. Continuous HLAPC coring resumed, and Cores 26F-41F penetrated from 359.8 to 431.4 mbsf (71.6 m) and recovered 48.82 m of sediment (68%).

Because the formation was getting quite firm and we had obtained suitable cores from this section, we decided to stop piston coring. We decided that we would reenter this hole with the RCB system to core our deep objectives below ~770 mbsf. We circulated 30 barrels of mud to clear cuttings out of the hole and started raising the bit back up the hole at 1530 h on 24 March. After pulling a couple stands of pipe, we removed the top drive and continued pulling out of the hole. When the bit reached 77.4 m, we assembled a FFF around the drill string and dropped it through the moonpool at 1850 h on 24 March. We waited 1 h to allow the FFF to land, pulled the bit out of the hole at 1955 h, and retrieved the drill string. The APC bit arrived back on the rig floor at 0145 h on 25 March. After a couple of hours servicing the rig (drill line slip and cut; lubricating crown sheave and main blocks; 0230 to 0445 h), we assembled an RCB BHA with a MBR (to allow for any potential logging) and lowered it to the seafloor. The camera system was deployed and we re-entered the Hole U1455C FFF after only ~15 min of maneuvering at 1540 h on 25 March. The camera system was retrieved, and we lowered the bit to 219.4 mbsf before it encountered any resistance. The top drive was installed, and we washed and reamed back down to the bottom of the cored part of the hole (431.4 m). We deployed a center bit and started to drill ahead without coring at 2215 h on 25 March.

At 0945 h on 26 March, we finished penetrating to 773 mbsf (DSDP Site 218 had cored to 773 mbsf). The center bit was retrieved and then redeployed in the middle of this drilled interval to ensure it could be removed and to tighten all connections in the core barrel. When the bit reached 773 mbsf, we retrieved the center bit, circulated mud to clean cuttings out of the hole, and started RCB coring at 2030 h on 26 March. Cores 43R-60R penetrated 176.0 m (773.0 to 949.0 mbsf) and recovered 59.36 m of sediment (34%). Coring ended when the operational time for the expedition expired; the last core of Expedition 354 arrived on deck at 1435 h on 28 March. We pulled the drill string out of the formation with the top drive in place until hole conditions were good enough to remove the top drive. The bit cleared the seafloor at 2120 h on 28 March, and it arrived back on the rig floor at 0640 h on 29 March. The BHA was taken apart, the rig floor was secured, the thrusters were raised, and we started our transit to Colombo, Sri Lanka, at 0645 h on 29 March.

## Transit to Colombo, Sri Lanka

After the 513 nmi transit, we arrived at Colombo at 0600 on 31 March 2015.
## References

Acharyya, S.K., Ray, K.K., and Sengupta, S., 1991. The Naga Hills and Andaman ophiolite belt, their setting, nature and collisional emplacement history. *Physics and Chemistry of the Earth*, 18(1):293–315.
http://dx.doi.org/10.1016/0079-1946(91)90006-2

Aitchison, J.C., Ali, J.R., and Davis, A.M., 2007. When and where did India and Asia collide? *Journal of Geophysical Research: Solid Earth*, 112(B5):B05423. http://dx.doi.org/10.1029/2006JB004706

Avouac, J.P., and Burov, E.B., 1996. Erosion as a driving mechanism of intra-continental mountain growth. *Journal of Geophysical Research: Solid Earth*, 101(B8):17747–17769. http://dx.doi.org/10.1029/96JB01344

Beerling, D.J., and Royer, D.L., 2011. Convergent Cenozoic CO₂ history. *Nature Geoscience*, 4(7):418–420. http://dx.doi.org/10.1038/ngeo1186

Bender, F., 1983. *Geology of Burma*: Berlin (Gebrüder Borntraeger).

Boulègue, J., and Bariac, T., 1990. Oxygen and hydrogen isotope ratios of interstitial waters from an intraplate deformation area: Bengal Fan, Leg 116. In Cochran, J.R., Stow, D.A.V., et al., *Proceedings of the Ocean Drilling Program, Scientific Results*, 116: College Station, TX (Ocean Drilling Program), 127–133. http://dx.doi.org/10.2973/odp.proc.sr.116.133.1990

Boos, W.R., and Kuang, Z., 2010. Dominant control of the South Asian monsoon by orographic insulation versus plateau heating. *Nature*, 463(7278):218–222. http://dx.doi.org/10.1038/nature08707

Bouquillon, A., France-Lanord, C., Michard, A., and Tiercelin, J.-J., 1990. Sedimentology and isotopic chemistry of the Bengal Fan sediments: the denudation of the Himalaya. In Cochran, J.R., Stow, D.A.V., et al., *Proceedings of the Ocean Drilling Program, Scientific Results*, 116: College Station, TX (Ocean Drilling Program), 43–58.
http://dx.doi.org/10.2973/odp.proc.sr.116.117.1990

Brunnschweiler, R.O., 1966. On the geology of Indoburman ranges. *Journal of the Geological Society of Australia*, 13(1):137–194.
http://dx.doi.org/10.1080/00167616608728608

Burbank, D.W., Derry, L.A., and France-Lanord, C., 1993. Reduced Himalayan sediment production 8 Myr ago despite an intensified monsoon. *Nature*, 364(6432):48–50. http://dx.doi.org/10.1038/364048a0

Cande, S.C., and Kent, D.V., 1995. Revised calibration of the geomagnetic polarity timescale for the Late Cretaceous and Cenozoic. *Journal of Geophysical Research: Solid Earth*, 100(B4):6093–6095.
http://dx.doi.org/10.1029/94JB03098

Cerling, T., 1997. Late Cenozoic vegetation change, atmospheric CO₂, and tectonics. In Ruddiman, W.F. (Ed.), *Tectonic Uplift and Climate Change: New York (Plenum)*, 313–327.

Clift, P.D., 2006. Controls on the erosion of Cenozoic Asia and the flux of clastic sediment to the ocean. *Earth and Planetary Science Letters*, 241(3–4):571–580. http://dx.doi.org/10.1016/j.epsl.2005.11.028

Clift, P.D., Hodges, K.V., Heslop, D., Hannigan, R., Long, H.V., and Calves, G., 2008. Correlation of Himalayan exhumation rates and Asian monsoon intensity. *Nature Geoscience*, 1(12):875–880.
http://dx.doi.org/10.1038/ngeo351

Cochran, J.R., 1990. Himalayan uplift, sea level, and the record of Bengal Fan sedimentation at the ODP Leg 116 sites. In Cochran, J.R., Stow, D.A.V., et al., *Proceedings of the Ocean Drilling Program, Scientific Results*, 116: College Station, TX (Ocean Drilling Program), 397–414.
http://dx.doi.org/10.2973/odp.proc.sr.116.144.1990

Cochran, J.R., Stow, D.A.V., et al., 1989. *Proceedings of the Ocean Drilling Program, Initial Reports*, 116: College Station, TX (Ocean Drilling Program).
http://dx.doi.org/10.2973/odp.proc.ir.116.1989

Contreras-Rosales, L.A., Jennerjahn, T., Tharammal, T., Meyer, V., Lückge, A., Paul, A., and Schefuß, E., 2014. Evolution of the Indian Summer Monsoon and terrestrial vegetation in the Bengal region during the past 18 ka. *Quaternary Science Reviews*, 102:133–148.
http://dx.doi.org/10.1016/j.quascirev.2014.08.010

Copeland, P., and Harrison, T.M., 1990. Episodic rapid uplift in the Himalaya revealed by ⁴⁰Ar/³⁹Ar analysis of detrital K-feldspar and muscovite, Bengal Fan. *Geology*, 18(4):354–357.
http://dx.doi.org/10.1130/0091-7613(1990)018<0354:ERUITH>2.3.CO;2

Copley, A., Avouac, J.-P., and Royer, J.-Y., 2010. India-Asia collision and the Cenozoic slowdown of the Indian plate: implications for the forces driving plate motions. *Journal of Geophysical Research: Solid Earth*, 115(B3):B03410. http://dx.doi.org/10.1029/2009JB006634

Corrigan, J.D., and Crowley, K.D., 1992. Unroofing of the Himalayas: a view from apatite fission-track analysis of Bengal fan sediments. *Geophysical Research Letters*, 19(23):2345–2348.
http://dx.doi.org/10.1029/92GL02743

Curray, J.R., 1994. Sediment volume and mass beneath the Bay of Bengal. *Earth and Planetary Science Letters*, 125(1–4):371–383.
http://dx.doi.org/10.1016/0012-821X(94)90227-5

Curray, J.R., Emmel, F.J., and Moore, D.G., 2003. The Bengal Fan: morphology, geometry, stratigraphy, history and processes. *Marine and Petroleum Geology*, 19(10):1191–1223. http://dx.doi.org/10.1016/S0264-8172(03)00035-7

Curray, J.R., Emmel, F.J., Moore, D.G., and Raitt, R.W., 1982. Structure, tectonics and geological history of the northeastern Indian Ocean. In Nairn, A.E.M., and Stehli, F.G. (Eds.), *The Ocean Basins and Margins* (Vol. 6): New York (Plenum), 399–450.

Curray, J.R., and Moore, D.G., 1974. Sedimentary and tectonic processes in the Bengal deep-sea fan and geosyncline. In Burk, C.A., and Drake, C.L. (Eds.), *The Geology of Continental Margins*: New York (Springer-Verlag), 617–627.

DeCelles, P.G., Gehrels, G.E., Najman, Y., Martin, A.J., Carter, A., and Garzanti, E., 2004. Detrital geochronology and geochemistry of Cretaceous–early Miocene strata of Nepal: implications for timing and diachroneity of initial Himalayan orogenesis. *Earth and Planetary Science Letters*, 227(3–4):313–330. http://dx.doi.org/10.1016/j.epsl.2004.08.019

DePaolo, D.J., and Ingram, B.L., 1985. High-resolution stratigraphy with strontium isotopes. *Science*, 227(4689):938–941.
http://dx.doi.org/10.1126/science.227.4689.938

Derry, L.A., and France-Lanord, C., 1996. Neogene Himalayan weathering history and river ⁸⁷Sr/⁸⁶Sr: impact on the marine Sr record. *Earth and Planetary Science Letters*, 142(1–2):59–74.
http://dx.doi.org/10.1016/0012-821X(96)00091-X

Derry, L.A., and France-Lanord, C., 1997. Himalayan weathering and erosion fluxes: climate and tectonic controls. In Ruddiman, W.F. (Ed.), *Tectonic Uplift and Climate Change*: New York (Plenum), 289–312.
http://dx.doi.org/10.1007/978-1-4615-5935-1_12

Dettman, D.L., Kohn, M.J., Quade, J., Ryerson, F.J., Ojha, T.P., and Hamidullah, S., 2001. Seasonal stable isotope evidence for a strong Asian monsoon throughout the past 10.7 m.y. *Geology*, 29(1):31–34.
http://dx.doi.org/10.1130/0091-7613(2001)029<0031:SSIEFA>2.0.CO;2

Duplessy, J.-C., 1982. Glacial to interglacial contrasts in the northern Indian Ocean. *Nature*, 295(5849):494–498.
http://dx.doi.org/10.1038/295494a0

Dupont-Nivet, G., Lippert, P.C., Van Hinsbergen, D.J.J., Meijers, M.J.M., and Kapp, P., 2010. Palaeolatitude and age of the Indo–Asia collision: palaeomagnetic constraints. *Geophysical Journal International*, 182(3):1189–1198. http://dx.doi.org/10.1111/j.1365-246X.2010.04697.x

Edmond, J.M., 1992. Himalayan tectonics, weathering processes, and the strontium isotope record in marine limestones. *Science*, 258(5088):1594–1597. http://dx.doi.org/10.1126/science.258.5088.1594

Fluteau, F., Ramstein, G., and Besse, J., 1999. Simulating the evolution of the Asian and African monsoons during the past 30 Myr using an atmospheric general circulation model. *Journal of Geophysical Research: Atmospheres*, 104(D10):11995–12018.
http://dx.doi.org/10.1029/1999JD900048

France-Lanord, C., and Derry, L.A., 1994. δ¹³C of organic carbon in the Bengal Fan: source evolution and transport of C3 and C4 plant carbon to marine sediments. *Geochimica et Cosmochimica Acta*, 58(21):4809–4814.
http://dx.doi.org/10.1016/0016-7037(94)90210-0

France-Lanord, C., and Derry, L.A., 1997. Organic carbon burial forcing of the carbon cycle from Himalayan erosion. *Nature*, 390(6655):65–67.
http://dx.doi.org/10.1038/36324
France-Lanord, C., Derry, L., and Michard, A., 1993. Evolution of the Himalaya since Miocene time: isotopic and sedimentological evidence from the Bengal Fan. *In Treloar, P.J., and Searle, M. (Eds.), *Himalayan Tectonics*. Geological Society Special Publication, 74(1):603-621.
http://dx.doi.org/10.1144/GSL.SP.1993.074.01.40

France-Lanord, C., Schwenk, T., and Klaus, A., 2014. Bengal Fan: Neogene and late Paleogene record of Himalayan orogeny and climate: a transect across the Middle Bengal Fan. *International Ocean Discovery Program Scientific Prospectus*, 354. doi:10.14379/iodp.sp.354.2014

Freeman, K.H., and Colarusso, L.A., 2001. Molecular and isotopic records of C₄ grassland expansion in the late Miocene. *Geochimica et Cosmochimica Acta*, 65(9):1439-1454. http://dx.doi.org/10.1016/S0016-7037(00)00573-1

Galy, A., and France-Lanord, C., 2001. Higher erosion rates in the Himalaya: geochemical constraints on riverine fluxes. *Geology*, 29(1):23-26.
http://dx.doi.org/10.1130/0091-7613(2001)029<0023:HER-ITH>2.0.CO;2

Galy, A., France-Lanord, C., and Derry, L.A., 1996. The late Oligocene-early Miocene Himalayan belt constraints deduced from isotopic compositions of early Miocene turbidites in the Bengal Fan. *Tectonophysics*, 260(1-3):109-118. http://dx.doi.org/10.1016/0040-1951(96)00079-0

Galy, A., France-Lanord, C., and Derry, L.A., 1999. The strontium isotopic budget of Himalayan rivers in Nepal and Bangladesh. *Geochimica et Cosmochimica Acta*, 63(13-14):1905-1925.
http://dx.doi.org/10.1016/S0016-7037(99)00081-2

Galy, V., Beyssac, O., France-Lanord, C., and Eglinton, T., 2008. Recycling of graphite during Himalayan erosion: a geological stabilization of carbon in the crust. *Science*, 322(5903):943-945. http://dx.doi.org/10.1126/science.1161408

Galy, V., Eglinton, T., France-Lanord, C., and Sylva, S., 2011. The provenance of vegetation and environmental signatures encoded in vascular plant biomarkers carried by the Ganges-Brahmaputra rivers. *Earth and Planetary Science Letters*, 304(1-2):1-12.

http://dx.doi.org/10.1016/j.epsl.2011.02.003

Galy, V., France-Lanord, C., Beyssac, O., Faure, P., Kudrass, H., and Palhol, F., 2007. Efficient organic carbon burial in the Bengal Fan sustained by the Himalayan erosional system. *Nature*, 450(7168):407-410.

http://dx.doi.org/10.1038/nature06273

Galy, V., France-Lanord, C., Peucker-Ehrenbrink, B., and Huyghe, P., 2010. Sr-Nd-Os evidence for a stable erosion regime in the Himalaya during the past 12 Myr. *Earth and Planetary Science Letters*, 290(3-4):474-480.

http://dx.doi.org/10.1016/j.epsl.2010.01.004

Galy, V., François, L., France-Lanord, C., Faure, P., Kudrass, H., Palhol, F., and Singh, S.K., 2008. C4 plants decline in the Himalayan basin since the Last Glacial Maximum. *Quaternary Science Reviews*, 27(13-14):1396-1409.

http://dx.doi.org/10.1016/j.qnaturev.2008.04.005

Gartner, S., 1990. Neogene calcareous nannofossil biostratigraphy, Leg 116 (central Indian Ocean). In Cochran, J.R., Stow, D.A.V., et al., *Proceedings of the Ocean Drilling Program, Scientific Results*, 116: College Station, TX (Ocean Drilling Program), 165-187.

http://dx.doi.org/10.2973/odp.proc.sr.116.122.1990

Garzanti, E., Andò, S., France-Lanord, C., Vezzoli, G., Censi, P., Galy, V., and Najman, Y., 2010. Mineralogical and chemical variability of fluvial sediments: 1. Bedload sand (Ganga-Brahmaputra, Bangladesh). *Earth and Planetary Science Letters*, 299(3-4):368-381.

http://dx.doi.org/10.1016/j.epsl.2010.09.017

Gasparotto, G., Spadafora, E., Summa, V., and Tateo, F., 2000. Contribution of grain size and compositional data from the Bengal Fan sediment to the understanding of Toba volcanic event. *Marine Geology*, 162(2-4):561-572. http://dx.doi.org/10.1016/S0025-3227(99)00090-0

Goddéris, Y., and Donnadieu, Y., 2009. Biogeochemistry: climatic plant power. *Nature*, 460(7251):40-41. http://dx.doi.org/10.1038/460040a

Goodbred, S.L., Jr., and Kuehl, S.A., 1999. Holocene and modern sediment budgets for the Ganges-Brahmaputra river system: evidence for high-stand dispersal to flood-plain, shelf, and deep-sea depocenters. *Geology*, 27(6):559-562. http://dx.doi.org/10.1130/S0019-7613(1999)027<0559:HAMSBF>2.3.CO;2

Gopala Rao, D., Bhattacharya, G.C., Ramana, M.V., Subrahmanyam, V., Ramprasad, T., Krishna, K.S., Chaubey, A.K., Murty, G.P.S., Srinivas, K., Desa, M., Reddy, S.I., Ashalata, B., Subrahmanyam, C., Mital, G.S., Drolia, R.K., Rai, S.N., Ghosh, S.K., Singh, R.N., and Majumdar, R., 1994. Analysis of multi-channel seismic reflection and magnetic data along 13°N latitude across the Bay of Bengal. *Marine Geophysical Research*, 16(3):225-236. http://dx.doi.org/10.1007/BF01237515

Gopala Rao, D., Krishna, K.S., and Sar, D., 1997. Crustal evolution and sedimentation history of the Bay of Bengal since the Cretaceous. *Journal of Geophysical Research: Solid Earth*, 102(B8):17747-17768.

http://dx.doi.org/10.1029/96JB01339

Heezen, B.C., and Tharp, M., 1966. Physiography of the Indian Ocean. *Philosophical Transactions of the Royal Society, A: Mathematical, Physical & Engineering Sciences*, 259(1099):137-149.

http://dx.doi.org/10.1098/rsta.1966.0003

Hodell, D.A., Mueller, P.A., McKenzie, J.A., and Mead, G.A., 1989. Strontium isotope stratigraphy and geochemistry of the late Neogene ocean. *Earth and Planetary Science Letters*, 92(2):165-178.

http://dx.doi.org/10.1016/0012-821X(89)90044-7

Hübscher, C., Spieß, V., Breitzke, M., and Weber, M.E., 1997. The youngest channel-levee system of the Bengal Fan: results from digital sediment echosounder data. *Marine Geology*, 141(1-4):125-145.

http://dx.doi.org/10.1016/S0025-3227(97)00066-2

Karunakaran, C., Ray, K.K., Sen, C.R., Saha, S.S., and Sarkar, S.K., 1975. Geology of the great Nicobar Island. *Journal of the Geological Society of India*, 16:135-142.

Kingston, J., 1986. Undiscovered petroleum resources of South Asia. *USGS Open-File Report*, 86-80. http://pubs.er.usgs.gov/publication/ofr8680

Koopnick, R.B., Burke, W.H., Denison, R.E., Hetherington, E.A., Nelson, H.F., Otto, J.B., and Waite, L.E., 1985. Construction of the seawater ⁸⁷Sr/⁸⁶Sr curve for the Cenozoic and Cretaceous: supporting data. *Chemical Geology: Isotope Geoscience section*, 58(1-2):55-81.

http://dx.doi.org/10.1016/0168-9622(85)90027-2

Kottke, B., Schwenk, T., Breitzke, M., Wiedicke, M., Kudrass, H.R., and Spiess, V., 2003. Acoustic facies and depositional processes in the upper submarine canyon Swatch of No Ground (Bay of Bengal). *Deep Sea Research Part II: Topical Studies in Oceanography*, 50(5):979-1001.

http://dx.doi.org/10.1016/S0967-0645(02)00616-1

Krishna, K.S., Bull, J.M., and Scrutton, R.A., 2001. Evidence for multiphase folding of the central Indian Ocean lithosphere. *Geology*, 29(8):715-718.

http://dx.doi.org/10.1130/0091-7613(2001)029<0715:EFMFOT>2.0.CO;2

Krishna, K.S., Ramana, M.V., Gopala Rao, D., Murthy, K.S.R., Malleswara Rao, M.M., Subrahmanyan, V., and Sarma, K.V.L.N.S., 1998. Periodic deformation of oceanic crust in the central Indian Ocean. *Journal of Geophysical Research: Solid Earth*, 103(B8):17859-17875.

http://dx.doi.org/10.1029/98JB00078

Krishnaswami, S., Trivedi, J.R., Sarin, M.M., Ramesh, R., and Sharma, K.K., 1992. Strontium isotopes and rubidium in the Ganga-Brahmaputra river system: weathering in the Himalaya, fluxes to the Bay of Bengal and contributions to the evolution of oceanic ⁸⁷Sr/⁸⁶Sr. *Earth and Planetary Science Letters*, 109(1-2):243-253. http://dx.doi.org/10.1016/0012-821X(92)90087-C

Kroon, D., Steens, T., and Troelstra, S.R., 1991. Onset of monsoonal related upwelling in the western Arabian Sea as revealed by planktonic foraminifers. *In Prell, W.L., Niitsuma, N., et al., Proceedings of the Ocean Drilling Program, Scientific Results*, 117: College Station, TX (Ocean Drilling Program), 257-263. http://dx.doi.org/10.2973/odp.proc.sr.117.126.1991

Kudrass, H.R., Michels, K.H., Wiedicke, M., and Suckow, A., 1998. Cyclones and tides as feeders of a submarine canyon off Bangladesh. *Geology*, 26(8): 715-718. http://dx.doi.org/10.1130/0091-7613(1998)026<0715:CATAFO>2.3.CO;2

Licht, A., van Cappelle, M., Abels, H.A., Ladant, J.-B., Trabucho-Alexandre, J., France-Lanord, C., Donnadieu, Y., Vandenberghe, J., Rigaudier, T., Lécuyer, C., Terry, D., Jr., Adriaens, R., Boura, A., Guo, Z., Soe, A.N., Quade, J., Dupont-Nivet, G., and Jaeger, J.-J., 2014. Asian monsoons in a
late Eocene greenhouse world. *Nature*, 513(7519):501–506.

http://dx.doi.org/10.1038/nature13704

Lupker, M., France-Lanord, C., Galy, V., Lavé, J., Gaillardet, J., Gajurel, A.P., Guilmette, C., Rahman, M., Singh, S.K., and Sinha, R., 2012. Predominant floodplain over mountain weathering of Himalayan sediments (Ganga basin). *Geochimica et Cosmochimica Acta*, 84:410–432.

http://dx.doi.org/10.1016/j.gca.2012.02.001

Lupker, M., France-Lanord, C., Galy, V., Lavé, J., and Kudrass, H., 2013. Increasing chemical weathering in the Himalayan system since the Last Glacial Maximum. *Earth and Planetary Science Letters*, 365:243–252.

http://dx.doi.org/10.1016/j.epsl.2013.01.038

Lupker, M., France-Lanord, C., Lavé, J., Bouchez, J., Galy, V., Métivier, F., Gaillardet, J., Lartiges, B., and Mugnier, J.-L., 2011. A Rouse-based method to integrate the chemical composition of river sediments: application to the Ganga Basin. *Journal of Geophysical Research: Earth Surface*, 116(F4):F04012. http://dx.doi.org/10.1029/2010JF001947

Martinod, J., and Molnar, P., 1995. Lithospheric folding in the Indian Ocean and the rheology of the oceanic plate. *Bulletin de la Societe Geologique de France*, 166(6):813–821. http://bsgf.geoscienceworld.org/content/166/6/813.extract

Métivier, F., Gaudemer, Y., Tapponnier, P., and Klein, M., 1999. Mass accumulation rates in Asia during the Cenozoic. *Geophysical Journal International*, 137(2):280–318. http://dx.doi.org/10.1046/j.1365-246X.1999.00802.x

Michels, K.H., Kudrass, H.R., Hübscher, C., Suckow, A., and Wiedicke, M., 1998. The submarine delta of the Ganges-Brahmaputra: cyclone-dominated sedimentation patterns. *Marine Geology*, 149(1–4):133–154.

Molnar, P., Boos, W.R., and Battisti, D.S., 2010. Orographic controls on climate and paleoclimate of Asia: thermal and mechanical roles for the Tibetan Plateau. *Annual Review of Earth and Planetary Sciences*, 38(1):77–102. http://dx.doi.org/10.1146/annurev-earth-040809-152456

Moore, D.G., Curray, J.R., Raitt, R.W., and Emmel, F.J., 1974. Stratigraphic-seismic section correlations and implications to Bengal Fan history. *In von der Borch, C.C., Sclater, J.G., et al., Initial Reports of the Deep Sea Drilling Project*, 22: Washington, DC (U.S. Government Printing Office), 403–412. http://dx.doi.org/10.2973/dsdp.proc.22.116.1974

Najman, Y., Bickle, M., BouDagher-Fadel, M., Carter, A., Garzanti, E., Paul, M., Wijbrans, J., Willett, E., Oliver, G., Parrish, R., Akhter, S.H., Allen, R., Ando, S., Chisty, E., Reisberg, L., and Vezzoli, G., 2008. The Paleogene record of Himalayan erosion: Bengal Basin, Bangladesh. *Earth and Planetary Science Letters*, 273(1–2):1–14.

http://dx.doi.org/10.1016/j.epsl.2008.04.028

Ormond, A., Boulègue, J., and Genthon, P., 1995. A thermoconvective interpretation of heat flow data in the area of Ocean Drilling Program Leg 116 in a distal part of the Bengal Fan. *Journal of Geophysical Research: Solid Earth*, 100(B5):8083–8095. http://dx.doi.org/10.1029/95JB00072

Pagani, M., Freeman, K.H., and Arthur, M.A., 1999. Late Miocene atmospheric CO₂ concentrations and expansion of C₄ grasses. *Science*, 285(5429):876–879. http://dx.doi.org/10.1126/science.285.5429.876

Palamenghi, L., Schwenk, T., Spiess, V., and Kudrass, H.R., 2011. Seismostratigraphic analysis with centennial to decadal time resolution of the sediment sink in the Ganges-Brahmaputra subaqueous delta. *Continental Shelf Research*, 31(6):712–730.

http://dx.doi.org/10.1016/j.csr.2011.01.008

Peirce, J., Weissel, J., et al., 1989. *Proceedings of the Ocean Drilling Program, Initial Reports*, 121: College Station, TX (Ocean Drilling Program).

http://dx.doi.org/10.2973/odp.proc.ir.121.1989

Pierson-Wickmann, A.-C., Reisberg, L., France-Lanord, C., and Kudrass, H.R., 2001. Os-Sr-Nd results from sediments in the Bay of Bengal: implications for sediment transport and the marine Os record. *Paleoecophysiology*, 16(4):435–444. http://dx.doi.org/10.1029/2000PA000532

Quade, J., and Cerling, T.E., 1995. Expansion of C₄ grasses in the late Miocene of northern Pakistan: evidence from stable isotopes in paleosols. *Palaeogeography, Palaeoclimatology, Palaeoecology*, 115(1–4):91–116.

http://dx.doi.org/10.1016/0031-0182(94)00108-K

Quade, J., Cerling, T.E., and Bowman, J.R., 1989. Development of Asian monsoon revealed by marked ecological shift during the latest Miocene in northern Pakistan. *Nature*, 342(6246):163–166.

http://dx.doi.org/10.1038/342163a0

Ramstein, G., Fluteau, F., Besse, J., and Joussaume, S., 1997. Effect of orogeny, plate motion and land-sea distribution on Eurasian climate change over the past 30 million years. *Nature*, 386(6627):788–795.

http://dx.doi.org/10.1038/386788a0

Raymo, M.E., and Ruddiman, W.F., 1992. Tectonic forcing of late Cenozoic climate. *Nature*, 359(6391):117–122.

http://dx.doi.org/10.1038/359117a0

Richter, F.M., Rowley, D.A., and DePaolo, D.J., 1992. Sr isotope evolution of seawater: the role of tectonics. *Earth and Planetary Science Letters*, 109(1–2):11–23. http://dx.doi.org/10.1016/0012-821X(92)90070-C

Rowley, D.B., 1996. Age of initiation of collision between India and Asia: a review of stratigraphic data. *Earth and Planetary Science Letters*, 145(1–4):1–13. http://dx.doi.org/10.1016/S0012-821X(96)00201-4

Rowley, D.B., 1998. Minimum age of initiation of collision between India and Asia north of Everest based on the subsidence history of the Zhepure Mountain section. *Journal of Geology*, 106(2):229–235.

http://dx.doi.org/10.1086/516018

Schwenk, T., and Spieß, V., 2009. Architecture and stratigraphy of the Bengal Fan as response to tectonic and climate revealed from high-resolution seismic data. *In Kneller, B.C., Martinsen, O.J., and McCaffrey, B. (Eds.), External Controls on Deep-Water Depositional Systems*. Special Publication - SEPM (Society of Sedimentary Geologists), 92:107–131.

Schwenk, T., Spieß, V., Hübscher, C., and Breitzke, M., 2003. Frequent channel avulsions within the active channel-levee system of the middle Bengal Fan—an exceptional channel-levee development derived from Parasound and Hydrosweep data. *Deep Sea Research Part II: Topical Studies in Oceanography*, 50(5):1023–1045. http://dx.doi.org/10.1016/S0967-0645(02)00618-5

Shipboard Scientific Party, 1974. Site 218. *In von der Borch, C.C., Sclater, J.G., et al., Initial Reports of the Deep Sea Drilling Project*, 22: Washington, DC (U.S. Government Printing Office), 325–338.

http://dx.doi.org/10.2973/dsdp.proc.22.109.1974

Shipboard Scientific Party, 1989a. Site 717: Bengal Fan. *In Cochran, J.R., Stow, D.A.V., et al., Proceedings of the Ocean Drilling Program, Initial Reports*, 116: College Station, TX (Ocean Drilling Program), 45–89.

http://dx.doi.org/10.2973/odp.proc.ir.116.105.1989

Shipboard Scientific Party, 1989b. Site 718: Bengal Fan. *In Cochran, J.R., Stow, D.A.V., et al., Proceedings of the Ocean Drilling Program, Initial Reports*, 116: College Station, TX (Ocean Drilling Program), 91–154.

http://dx.doi.org/10.2973/odp.proc.ir.116.106.1989

Shipboard Scientific Party, 1989c. Site 719: Bengal Fan. *In Cochran, J.R., Stow, D.A.V., et al., Proceedings of the Ocean Drilling Program, Initial Reports*, 116: College Station, TX (Ocean Drilling Program), 155–196.

http://dx.doi.org/10.2973/odp.proc.ir.116.107.1989

Spiess, V., Hübscher, C., Breitzke M., Böke, W., Krell, A., von Larcher, T., Matschkowski, T., Schwenk, T., Wessels, A., Zühldorff, L., and Zühlsdorff, S., 1998. Report and preliminary results of R/V Sonne Cruise 125, Cochin-Chittagong, 17.10–17.11.97. *Berichte aus dem Fachbereich Geowissenschaften der Universität Bremen*, 123. http://elib.suub.uni-bremen.de/ip/docs/00010242.pdf

Stow, D.A.V., Amano, K., Balson, P.S., Brass, G.W., Corrigan, J., Raman, C.V., Tiercelin, J.-J., Townsend, M., and Wijayananda, N.P., 1990. Sediment facies and processes on the distal Bengal Fan, Leg 116. *In Cochran, J.R., Stow, D.A.V., et al., Proceedings of the Ocean Drilling Program, Scientific Results*, 116: College Station, TX (Ocean Drilling Program), 377–396.

http://dx.doi.org/10.2973/odp.proc.sr.116.110.1990

van Hinsbergen, D.J.J., Steinberger, B., Doubrovine, P.V., and Gassmöller, R., 2011. Acceleration and deceleration of India-Asia convergence since the Cretaceous: roles of mantle plumes and continental collision. *Journal of*
*Geophysical Research: Solid Earth*, 116(B6):B06101.

http://dx.doi.org/10.1029/2010JB008051

von der Borch, C.C., Sclater, J.G., et al., 1974. *Initial Reports of the Deep Sea Drilling Project*, 22: Washington (U.S. Government Printing Office).

http://dx.doi.org/10.2973/dsdp.proc.22.1974

Weber, M.E., Wiedicke, M.H., Kudrass, H.R., Hübscher, C., and Erlenkeuser, H., 1997. Active growth of the Bengal Fan during sea-level rise and high-stand. *Geology*, 25(4):315–318.

http://dx.doi.org/10.1130/0091-7613(1997)025<0315:AGOTBF>2.3.CO;2

Weber, M.E., Wiedicke-Hombach, M., Kudrass, H.R., and Erlenkeuser, H., 2003. Bengal Fan sediment transport activity and response to climate forcing inferred from sediment physical properties. *Sedimentary Geology*, 155(3–4), 361–381. http://dx.doi.org/10.1016/S0037-0738(02)00187-2

Willenbring, J.K., and von Blanckenburg, F., 2010. Long-term stability of global erosion rates and weathering during late-Cenozoic cooling.

*Nature*, 465(7295):211–214. http://dx.doi.org/10.1038/nature09044

Zachos, J., Pagani, M., Sloan, L., Thomas, E., and Billups, K., 2001. Trends, rhythms, and aberrations in global climate 65 Ma to present. *Science*, 292(5517):686–693. http://dx.doi.org/10.1126/science.1059412

Zhang, P., Molnar, P., and Downs, W.R., 2001. Increased sedimentation rates and grain sizes 2–4 Myr ago due to the influence of climate change on erosion rates. *Nature*, 410(6831):891–897.

http://dx.doi.org/10.1038/35073504

Zhang, Q., Willems, H., Ding, L., Gräfe, K.-U., and Appel, E., 2012. Initial India-Asia continental collision and foreland basin evolution in the Tethyan Himalaya of Tibet: evidence from stratigraphy and paleontology.

*Journal of Geology*, 120(2):175–189. http://dx.doi.org/10.1086/663876

Zhisheng, A., Kutzbach, J.E., Prell, W.L., and Porter, S.C., 2001. Evolution of Asian monsoons and phased uplift of the Himalaya–Tibetan plateau since late Miocene times. *Nature*, 411(6833):62–66.

http://dx.doi.org/10.1038/35075035
<table><caption>Table T1. Operations summary. See Figure F4 for location of drill sites. Download table in .csv format.</caption><thead><tr><th>Hole</th><th>Proposed site</th><th>Location</th><th>Water depth (mbsl)</th><th>Total penetration (m)</th><th>Interval cored (m)</th><th>Interval drilled without coring (m)</th><th>Core recovery (m)</th><th>Core recovery (%)</th><th>Time on hole (d)</th><th>Cores (N)</th></tr></thead><tbody><tr><td colspan="11"><strong>354-</strong></td></tr><tr><td>U1449A</td><td>MBF-6A</td><td>8°0.4194′N, 88°6.5994′E</td><td>3652.7</td><td>213.5</td><td>212.5</td><td>1.0</td><td>129.38</td><td>61</td><td>2.9</td><td>37</td></tr><tr><td>U1449B</td><td></td><td>8°0.4206′N, 88°6.6091′E</td><td>3651.9</td><td>7.9</td><td>7.9</td><td>0</td><td>7.91</td><td>100</td><td>0.5</td><td>1</td></tr><tr><td></td><td></td><td>Site U1449 totals:</td><td></td><td>221.4</td><td>220.4</td><td>1.0</td><td>137.29</td><td>62</td><td>3.4</td><td>38</td></tr><tr><td>U1450A</td><td>MBF-2A</td><td>8°0.4201′N, 87°40.2478′E</td><td>3655.3</td><td>687.4</td><td>444.7</td><td>242.7</td><td>282.73</td><td>64</td><td>6.4</td><td>86</td></tr><tr><td>U1450B</td><td></td><td>8°0.4192′N, 87°40.2586′E</td><td>3655.4</td><td>811.9</td><td>203.9</td><td>608.0</td><td>46.67</td><td>23</td><td>4.0</td><td>21</td></tr><tr><td></td><td></td><td>Site U1450 totals:</td><td></td><td>1499.3</td><td>648.6</td><td>850.7</td><td>329.40</td><td>51</td><td>10.4</td><td>107</td></tr><tr><td>U1451A</td><td>MBF-3A</td><td>8°0.4195′N, 88°44.5012′E</td><td>3607.3</td><td>582.1</td><td>394.9</td><td>187.2</td><td>337.80</td><td>86</td><td>4.8</td><td>72</td></tr><tr><td>U1451B</td><td></td><td>8°0.4203′N, 88°44.4745′E</td><td>3607.2</td><td>1181.3</td><td>627.6</td><td>553.7</td><td>180.86</td><td>29</td><td>13.1</td><td>70</td></tr><tr><td></td><td></td><td>Site U1451 totals:</td><td></td><td>1763.4</td><td>1022.5</td><td>740.9</td><td>518.66</td><td>51</td><td>17.9</td><td>142</td></tr><tr><td>U1452A</td><td>MBF-5A</td><td>8°0.4196′N, 87°10.9001′E</td><td>3670.5</td><td>8.0</td><td>8.0</td><td>—</td><td>8.03</td><td>100</td><td>0.6</td><td>1</td></tr><tr><td>U1452B</td><td></td><td>8°0.4191′N, 87°10.9128′E</td><td>3670.3</td><td>217.7</td><td>174.5</td><td>43.2</td><td>138.21</td><td>79</td><td>1.8</td><td>34</td></tr><tr><td>U1452C</td><td></td><td>8°0.4088′N, 87°10.9116′E</td><td>3671.5</td><td>41.3</td><td>41.3</td><td>—</td><td>33.30</td><td>81</td><td>0.8</td><td>6</td></tr><tr><td></td><td></td><td>Site U1452 totals:</td><td></td><td>267.0</td><td>223.8</td><td>43.2</td><td>179.54</td><td>80</td><td>3.1</td><td>41</td></tr><tr><td>U1453A</td><td>MBF-4A</td><td>8°0.4193′N, 86°47.8973′E</td><td>3679.5</td><td>215.7</td><td>186.7</td><td>29.0</td><td>164.78</td><td>88</td><td>3.6</td><td>37</td></tr><tr><td></td><td></td><td>Site U1453 totals:</td><td></td><td>215.7</td><td>186.7</td><td>29.0</td><td>164.78</td><td>88</td><td>3.6</td><td>37</td></tr><tr><td>U1454A</td><td>MBF-7A</td><td>8°0.4067N, 85°50.9882′E</td><td>3709.9</td><td>7.5</td><td>7.5</td><td>—</td><td>7.54</td><td>101</td><td>0.4</td><td>1</td></tr><tr><td>U1454B</td><td></td><td>8°0.4083′N, 85°51.0025′E</td><td>3710.3</td><td>161.8</td><td>147.4</td><td>14.4</td><td>129.51</td><td>88</td><td>1.6</td><td>29</td></tr><tr><td>U1454C</td><td></td><td>8°0.3968′N, 85°51.0033′E</td><td>3710.3</td><td>37.2</td><td>37.2</td><td>—</td><td>30.16</td><td>81</td><td>0.4</td><td>6</td></tr><tr><td>U1454D</td><td></td><td>8°0.3975′N, 85°50.9927′E</td><td>3710.7</td><td>37.1</td><td>37.1</td><td>—</td><td>24.46</td><td>66</td><td>3.4</td><td>5</td></tr><tr><td></td><td></td><td>Site U1454 totals:</td><td></td><td>243.6</td><td>229.2</td><td>14.4</td><td>191.67</td><td>84</td><td>5.7</td><td>41</td></tr><tr><td>U1455A</td><td>MBF-1A</td><td>8°0.4189′N, 86°16.9983′E</td><td>3732.5</td><td>0.9</td><td>0.9</td><td>—</td><td>0.90</td><td>100</td><td>0.4</td><td>1</td></tr><tr><td>U1455B</td><td></td><td>8°0.4198′N, 86°17.0096′E</td><td>3733.0</td><td>6.9</td><td>6.9</td><td>—</td><td>6.88</td><td>100</td><td>0.1</td><td>1</td></tr><tr><td>U1455C</td><td></td><td>8°0.4081′N, 86°17.0090′E</td><td>3732.5</td><td>949.0</td><td>350.7</td><td>598.3</td><td>198.00</td><td>56</td><td>7.1</td><td>54</td></tr><tr><td></td><td></td><td>Site U1455 totals:</td><td></td><td>956.8</td><td>358.5</td><td>598.3</td><td>205.8</td><td>57</td><td>7.56</td><td>56</td></tr><tr><td></td><td></td><td>Expedition 354 totals:</td><td></td><td>5167.2</td><td>2889.7</td><td>2277.5</td><td>1727.12</td><td>60</td><td>51.6</td><td>462</td></tr><tr><td colspan="11"><strong>353-</strong></td></tr><tr><td>U1444A</td><td>MBF-10</td><td>14°0.0057′N, 84°49.7405′E</td><td>3127.7</td><td>330.6</td><td>330.6</td><td>0.0</td><td>226.05</td><td>68</td><td>3.0</td><td>37</td></tr><tr><td>U1444B</td><td></td><td>13°59.9940′N, 84°49.7412′E</td><td>3131.8</td><td>128.6</td><td>81.1</td><td>47.5</td><td>74.16</td><td>91</td><td>1.0</td><td>9</td></tr><tr><td></td><td></td><td>Expedition 353 totals:</td><td></td><td>459.2</td><td>411.7</td><td>47.5</td><td>300.21</td><td>73</td><td>3.9</td><td>46</td></tr></tbody></table>
Figure F1. Cenozoic changes: global cooling and glaciations (Zachos, 2001), Oligocene atmospheric PCO₂ drawdown (Beerling and Royer, 2011) possibly related to a change in the balance between erosion and volcanic input of CO₂, Oligocene rise of seawater ⁸⁷Sr/⁸⁶Sr (Koepnick et al., 1985) likely reflecting the erosion of radiogenic formations analog of the modern Himalaya, and Eocene slowdown of the Indian plate motion following the collision and Tibet Uplift (Copley et al., 2010). Right: extent of existing sedimentary records in the Bengal fan and Himalayan foreland.

<figure><img src="image_3.png" /></figure>

Figure F2. Map of the Himalayan erosion system showing the position of existing DSDP and ODP sites documenting the Bengal and Indus Fans or the monsoon history. Box = location of Expedition 354 Middle Bengal Fan (MBF) drill site transect at 8°N. Bengal Fan sediment isopachs (blue lines; in kilometers) are simplified from Currey et al. (2003) and represent the total sedimentary and metasedimentary rocks above the oceanic basalt as interpreted from seismic reflection and refraction data.

<figure><img src="image_4.png" /></figure>
Figure F3. A. Seismic Profile GeoB097-020/027 showing the positions of Expedition 354 drill sites in relation to regional fan architecture. The tops of the Pliocene and Miocene, as well as the 10 Ma horizon, are traced through the profile based on results from DSDP Site 218 (Moore et al., 1974). The distinct unconformity in the east penetrated only by the deepest part of Site U1451 is inferred to represent the Eocene onset of fan deposition. CMP = common midpoint. B. Interpreted line drawing of Profile GeoB097-020/027 showing the later stage channel-levee systems, regional unconformities, and faults. Modified from Schwenk and Spiess (2009). VE = vertical exaggeration. Horizontal scale = CMP, CMP distance = 20 m. Naming of channels follows Curray et al. (2003).

<figure><img src="image_5.png" /></figure>

<figure><img src="image_6.png" /></figure>
<figure><img src="image_7.png" /><figcaption>Figure F5. Compilation for the upper 250 m of the seven site drilling transect at 8°N from west to east, comprising subbottom depth axis, core numbers and recovery, and major and minor lithologies for the deepest hole at each site. Geographic longitude is given for each hole.</figcaption></figure>

<figure><img src="image_8.png" /></figure>
<figure><img src="image_9.png" /><figcaption>Figure F6. Compilation of the three deep holes of the drilling transect at 8°N from west to east, comprising subbottom depth axis, recovery, and major and minor lithologies for each site.</figcaption></figure>
Figure F7. Estimated age span of Bengal Fan sedimentation vs. distance from the present apex or source of the fan. Shaded area at each site = known age span of fan sedimentation. The duration of the apparent hiatus was short near the source and long in the lower and distal fan. This plot is oversimplified because the distance from the fan apex changed through time with convergence of the Indian and Eurasian plates and with progradation of the delta in Bangladesh. IB ranges = Indo-Burman ranges, A-N Ridge = Andaman-Nicobar Ridge. DSDP and ODP numbers are sites.

<figure><img src="image_10.png" /></figure>

Figure F8. Map showing proposed Expedition 354 drill sites of on top of multibeam bathymetry. Available seismic lines from R/V Sonne Cruises SO125 (black) and SO188 (red) are indicated. Profiles crossing the sites are highlighted. See Site summaries and appendix figures in France-Lanord et al. (2014) for seismic data at each proposed site.

<figure><img src="image_11.png" /></figure>
Figure F9. Accumulation rate (Gartner, 1990), clay mineralogy (Bouquillon et al., 1990), Nd isotopic data (Derry and France-Lanord, 1996; France-Lanord et al., 1993; Galy et al., 1996), and total organic carbon isotopic composition (France-Lanord and Derry, 1994), ODP Holes 717C and 718C. Ages recalculated using timescale of Cande and Kent (1995). Low sedimentation rates, smectite-kaolinite clays, and organic carbon derived from C₄ plants characterize the interval from 7.4 to 0.9 Ma. Nd isotopic composition does not change during the entire time recovered, suggesting the eroded source of material is not significantly changing. Biostratigraphic constraints on sediment accumulation are uncertain for the early Miocene. The apparent increase in sedimentation rate near 12 Ma could be an artifact of poor biostratigraphic control prior to that time.

<figure><img src="image_12.png" /><figcaption>Figure F10. Actual and planned Expedition 354 operations.</figcaption></figure>

<figure><img src="image_13.png" /></figure>