Mixing Zephyr Program
Dive 3001

Port Observer: Butterfield
Starboard Observer: Bain
Pilot: Heintz
Date: 9/21/95

Summary

Dive Goals: The main goal of this dive was to obtain water samples (gas tight and major discretes) from black smokers on the following sulfide structures in the northern portion of the Main Endeavour Vent Field: Dudley, Hulk, TP, Lobo, Grotto. Secondary goals included:

To explore selected site to southeast of Dudley for hydrothermal activity. Site determined through sonar swaths to have characteristics similar to those of known sulfide structures.

To retrieve a basalt sample at Dave Butterfield’s request.

To obtain biological samples containing sulfide worms (at John Baross’ request). Hot sulfides related to flanges were advised to be the best environment for such sampling.

To retrieve a salt water battery deployed by Will Wilcock approximately 10 meters north of Dudley.

To take three Niskin water samples for Betsy McLaughlin at heights of 50m, 100m, and 150m within a plume.

To run four north-south Mesotech lines over the Hulk/Crypto area.

Dive summary: We landed at 9:25 at coordinates X-5060, Y-6035. The exploratory site was given coordinates of X-5050, Y-6025. Once we landed, we headed for Dudley, the first sampling site. We did not see any sulfides prior to arriving at Dudley, but it is possible we passed the intended region to the north. Along the way, we added a sample of basalt to the basket. At Dudley we sampled a black smoker by marker AA, taking a hand-held major #4 and gas tight #5, recording a temperature of 338°C. We also broke off a piece of flange for the bio box. We then headed for Hulk, passing by Crypto and arriving near marker J on the north end of the structure. We spent five minutes searching for marker A3, to sample its adjacent smoker. Here we took the port inner and outer majors as well as the port gas tight. A high temperature of 325°C was recorded. Next we went to TP where we sampled a vigorous black smoker by marker L. We first placed a portion of a spire into the bio box. We then recorded a temperature of 355°C from the manifold, while taking the starboard inner major and starboard gas tight samples. In the process, we melted a portion of the manifold apparatus (sleeve?) and recorded an erroneous temperature reading of 500°C. We next headed for Lobo, where we tried to find a smoker around Marker F to sample. Not finding one suitable, we sampled a vent lying between an orange block floating marker, and a red disk-shaped marker. Here we took the hand-held major #5, and the 6-stripe gas tight samples. We then repositioned ourselves over a flange and filled the starboard outer major with diffuse flow. Following, we headed to Grotto, the last water sampling site. By marker K we took the hand-held double major along with the 7-stripe gas tight. We took our last sample, the 2-stripe gas tight, by marker BA, on Grotto as well. After sampling, we searched for the sea battery. When found, we conducted a 3-chip video survey upon the battery and surrounding area, then loaded the instrument into the basket. We had time left to run two north-south Mesotech lines over Crypto/Hulk before heading to the surface. On the rise up, over Dante, we fired two Niskin bottles at elevations of 50 and 90 feet. The middle Niskin had prematurely fired at some point during our dive.